Building new computational models to support health behavior change and maintenance: new opportunities in behavioral research.

Science.gov (United States)

Spruijt-Metz, Donna; Hekler, Eric; Saranummi, Niilo; Intille, Stephen; Korhonen, Ilkka; Nilsen, Wendy; Rivera, Daniel E; Spring, Bonnie; Michie, Susan; Asch, David A; Sanna, Alberto; Salcedo, Vicente Traver; Kukakfa, Rita; Pavel, Misha

2015-09-01

Adverse and suboptimal health behaviors and habits are responsible for approximately 40 % of preventable deaths, in addition to their unfavorable effects on quality of life and economics. Our current understanding of human behavior is largely based on static "snapshots" of human behavior, rather than ongoing, dynamic feedback loops of behavior in response to ever-changing biological, social, personal, and environmental states. This paper first discusses how new technologies (i.e., mobile sensors, smartphones, ubiquitous computing, and cloud-enabled processing/computing) and emerging systems modeling techniques enable the development of new, dynamic, and empirical models of human behavior that could facilitate just-in-time adaptive, scalable interventions. The paper then describes concrete steps to the creation of robust dynamic mathematical models of behavior including: (1) establishing "gold standard" measures, (2) the creation of a behavioral ontology for shared language and understanding tools that both enable dynamic theorizing across disciplines, (3) the development of data sharing resources, and (4) facilitating improved sharing of mathematical models and tools to support rapid aggregation of the models. We conclude with the discussion of what might be incorporated into a "knowledge commons," which could help to bring together these disparate activities into a unified system and structure for organizing knowledge about behavior.

Transcranial Direct Current Stimulation and behavioral models of smoking addiction

Directory of Open Access Journals (Sweden)

Paige eFraser

2012-08-01

Full Text Available While few studies have applied transcranial direct current stimulation (tDCS to smoking addiction, existing work suggests that the intervention holds promise for altering the complex system by which environmental cues interact with cravings to drive behavior. Imaging and repetitive transcranial magnetic stimulation (rTMS studies suggest that increased dorsolateral prefrontal cortex (DLPFC activation and integrity may be associated with increased resistance to smoking cues. Anodal tDCS of the DLPFC, believed to boost activation, reduces cravings in response to these cues. The finding that noninvasive stimulation modifies cue induced cravings has profound implications for understanding the processes underlying addiction and relapse. TDCS can also be applied to probe mechanisms underlying and supporting nicotine addiction, as was done in a pharmacologic study that applied nicotine, tDCS, and TMS paired associative stimulation to find that stopping nicotine after chronic use induces a reduction in plasticity, causing difficulty in breaking free from association between cues and cravings. This mini-review will place studies that apply tDCS to smokers in the context of research involving the neural substrates of nicotine addiction.

Human Guidance Behavior Decomposition and Modeling

Science.gov (United States)

Feit, Andrew James

Trained humans are capable of high performance, adaptable, and robust first-person dynamic motion guidance behavior. This behavior is exhibited in a wide variety of activities such as driving, piloting aircraft, skiing, biking, and many others. Human performance in such activities far exceeds the current capability of autonomous systems in terms of adaptability to new tasks, real-time motion planning, robustness, and trading safety for performance. The present work investigates the structure of human dynamic motion guidance that enables these performance qualities. This work uses a first-person experimental framework that presents a driving task to the subject, measuring control inputs, vehicle motion, and operator visual gaze movement. The resulting data is decomposed into subspace segment clusters that form primitive elements of action-perception interactive behavior. Subspace clusters are defined by both agent-environment system dynamic constraints and operator control strategies. A key contribution of this work is to define transitions between subspace cluster segments, or subgoals, as points where the set of active constraints, either system or operator defined, changes. This definition provides necessary conditions to determine transition points for a given task-environment scenario that allow a solution trajectory to be planned from known behavior elements. In addition, human gaze behavior during this task contains predictive behavior elements, indicating that the identified control modes are internally modeled. Based on these ideas, a generative, autonomous guidance framework is introduced that efficiently generates optimal dynamic motion behavior in new tasks. The new subgoal planning algorithm is shown to generate solutions to certain tasks more quickly than existing approaches currently used in robotics.

Model-independent study of light cone current commutators

International Nuclear Information System (INIS)

Gautam, S.R.; Dicus, D.A.

1974-01-01

An attempt is made to extract information on the nature of light cone current commutators (L. C. C.) in a model independent manner. Using simple assumptions on the validity of the DGS representation for the structure functions of deep inelastic scattering and using the Bjorken--Johnston--Low theorem it is shown that in principle the L. C. C. may be constructed knowing the experimental electron--proton scattering data. On the other hand the scaling behavior of the structure functions is utilized to study the consistency of a vanishing value for various L. C. C. under mild assumptions on the behavior of the DGS spectral moments. (U.S.)

Developing custom fire behavior fuel models from ecologically complex fuel structures for upper Atlantic Coastal Plain forests

Science.gov (United States)

Bernard R. Parresol; Joe H. Scott; Anne Andreu; Susan Prichard; Laurie Kurth

2012-01-01

Currently geospatial fire behavior analyses are performed with an array of fire behavior modeling systems such as FARSITE, FlamMap, and the Large Fire Simulation System. These systems currently require standard or customized surface fire behavior fuel models as inputs that are often assigned through remote sensing information. The ability to handle hundreds or...

The Current Status of Behaviorism and Neurofeedback

Science.gov (United States)

Fultz, Dwight E.

2009-01-01

There appears to be no dominant conceptual model for the process and outcomes of neurofeedback among practitioners or manufacturers. Behaviorists are well-positioned to develop a neuroscience-based source code in which neural activity is described in behavioral terms, providing a basis for behavioral conceptualization and education of…

The association of current smoking behavior with the smoking behavior of parents, siblings, friends and spouses

NARCIS (Netherlands)

Vink, J.M.; Willemsen, G.; Boomsma, D.I.

2003-01-01

Aims: To examine the association of current smoking behavior of adolescents and young adults with the smoking behavior of their parents, siblings, friends and spouses. Design: Using survey data from a large twin-family sample, the association between the smoking behavior of participants and that of

Transport critical current density in flux creep model

International Nuclear Information System (INIS)

Wang, J.; Taylor, K.N.R.; Russell, G.J.; Yue, Y.

1992-01-01

The magnetic flux creep model has been used to derive the temperature dependence of the critical current density in high temperature superconductors. The generally positive curvature of the J c -T diagram is predicted in terms of two interdependent dimensionless fitting parameters. In this paper, the results are compared with both SIS and SNS junction models of these granular materials, neither of which provides a satisfactory prediction of the experimental data. A hybrid model combining the flux creep and SNS mechanisms is shown to be able to account for the linear regions of the J c -T behavior which are observed in some materials

Behavioral effects of nerve agents: laboratory animal models

International Nuclear Information System (INIS)

Myers, T. M.

2009-01-01

Diverse and often subtle behavioral consequences have been reported for humans exposed to nerve agents. Laboratory studies of nerve agent exposure offer rigorous control over important variables, but species other than man must be used. Nonhuman primate models offer the best means of identifying the toxic nervous system effects of nerve agent insult and the countermeasures best capable of preventing or attenuating these effects. Comprehensive behavioral models must evaluate preservation and recovery of function as well as new learning ability. The throughput and sensitivity of the tests chosen are important considerations. A few nonhuman primate studies will be discussed to elaborate recent successes, current limitations, and future directions.(author)

SSWL and BWL: finite element models of compressed magnetic field current generators

Energy Technology Data Exchange (ETDEWEB)

Tucker, T.J.; Leeman, J.E.

1976-01-01

Documentation is presented for two new computer codes modeling the behavior of compressed magnetic field current generators. Code output results for the typical generator configurations are presented and compared to experimental results. (auth)

Development of three dimensional ocean current model for coastal region

International Nuclear Information System (INIS)

Kobayashi, Takuya

1999-12-01

In order to study the migration behavior of radionuclides released into a coastal region around Japan, Princeton Ocean Model (POM) was introduced. This three-dimensional ocean current model was modified to be applied for oceanic simulations around Japan. This report describes the governing equations, numerical methods and model improvements. In addition, database system which is utilized for calculations and visualization system for graphical outputs are also described. Model simulation was carried out at off the area of Shimokita. Aomori-ken, Japan to investigate the effects of the boundary conditions on simulated results. (author)

Behavioral cardiology: current advances and future directions.

Science.gov (United States)

Rozanski, Alan

2014-07-08

Growing epidemiological evidence identifies key domains relevant to behavioral cardiology, including health behaviors, emotions, mental mindsets, stress management, social connectedness, and a sense of purpose. Each of these domains exists along a continuum, ranging from positive factors that promote health, to negative factors, which are pathophysiological. To date, there has been relatively little translation of this growing knowledge base into cardiology practice. Four initiatives are proposed to meet this challenge: 1) promulgating greater awareness of the potency of psychosocial risks factors; 2) overcoming a current "artificial divide" between conventional and psychosocial risk factors; 3) developing novel cost-effective interventions using Internet and mobile health applications, group-based counseling, and development of tiered-care behavioral management; and 4) in recognition that "one size does not fit all" with respect to behavioral interventions, developing specialists who can counsel patients in multidisciplinary fashion and use evidence-based approaches for promoting patient motivation and execution of health goals. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Dual resonance models and their currents

International Nuclear Information System (INIS)

Johnson, E.A.

1978-01-01

It is shown how dual resonance models were rederived from the concept of a string tracing out a surface in space-time. Thus, interacting strings reproduce the dual amplitudes. A scheme for tackling the unitarity problem began to develop. As a consistent theory of hadronic processes began to be built, workers at the same time were naturally led to expect that leptons could be included with hadrons in a unified dual theory. Thus, there is a search for dual amplitudes which would describe interactions between hadrons and currents (for example, electrons), as well as interactions involving only hadrons. Such amplitudes, it is believed, will be the correct ones, describing the real world. Such amplitudes will provide valuable information concerning such things as hadronic form factors. The great difficulties in building current-amplitudes with the required properties of proper factorization on a good spectrum, duality, current algebra, and proper asymptotic behavior are described. Dual models at the present time require for consistency, an intercept value of α 0 = 1 and a dimension value of d = 26 (or d = 10). There have been speculations that the unphysical dimension may be made physical by associating the ''extra dimensions'' with certain internal degrees of freedom. However, it is desired that the theory itself, force the dimension d = 4. It is quite possible that the dimension problem and the intercept problem are tied together and that resolving either problem will resolve the other. Order by order, a new dual current is constructed that is manifestly factorizable and which appears to be valid for arbitrary space-time dimension. The fact that this current is not bound at d = 26, leads to interesting speculations on the nature of dual currents

Modeling and prediction of human word search behavior in interactive machine translation

Science.gov (United States)

Ji, Duo; Yu, Bai; Ma, Bin; Ye, Na

2017-12-01

As a kind of computer aided translation method, Interactive Machine Translation technology reduced manual translation repetitive and mechanical operation through a variety of methods, so as to get the translation efficiency, and played an important role in the practical application of the translation work. In this paper, we regarded the behavior of users' frequently searching for words in the translation process as the research object, and transformed the behavior to the translation selection problem under the current translation. The paper presented a prediction model, which is a comprehensive utilization of alignment model, translation model and language model of the searching words behavior. It achieved a highly accurate prediction of searching words behavior, and reduced the switching of mouse and keyboard operations in the users' translation process.

Current Trends in the Detection of Sociocultural Signatures: Data-Driven Models

Energy Technology Data Exchange (ETDEWEB)

Sanfilippo, Antonio P.; Bell, Eric B.; Corley, Courtney D.

2014-09-15

The harvesting of behavioral data and their analysis through evidence-based reasoning enable the detection of sociocultural signatures in their context to support situation awareness and decision making. Harvested data are used as training materials from which to infer computational models of sociocultural behaviors or calibrate parameters for such models. Harvested data also serve as evidence input that the models use to provide insights about observed and future behaviors for targets of interest. The harvested data is often the result of assembling diverse data types and aggregating them into a form suitable for analysis. Data need to be analyzed to bring out the categories of content that are relevant to the domain being addressed in order to train or run a model. If, for example, we are modeling the intent of a group to engage in violent behavior using messages that the group has broadcasted, then these messages need to be processed to extract and measure indicators of violent intent. The extracted indicators and the associated measurements (e.g. rates or counts of occurrence) can then be used to train/calibrate and run computational models that assess the propensity for violence expressed in the source message. Ubiquitous access to the Internet, mobile telephony and technologies such as digital photography and digital video have enabled social media application platforms such as Facebook, YouTube, and Twitter that are altering the nature of human social interaction. The fast increasing pace of online social interaction introduces new challenges and opportunities for gathering sociocultural data. Challenges include the development of harvesting and processing techniques tailored to new data environments and formats (e.g. Twitter, Facebook), the integration of social media content with traditional media content, and the protection of personal privacy. As these and other challenges are addressed, a new wealth of behavioral data and data analysis methods becomes

Detailed behavioral modeling of bang-bang phase detectors

DEFF Research Database (Denmark)

Jiang, Chenhui; Andreani, Pietro; Keil, U. D.

2006-01-01

In this paper, the metastability of current-mode logic (CML) latches and flip-flops is studied in detail. Based on the results of this analysis, a behavioral model of bang-bang phase detectors (BBPDs) is proposed, which is able to reliably capture the critical deadzone effect. The impact of jitter...

Analytical drift-current threshold voltage model of long-channel double-gate MOSFETs

International Nuclear Information System (INIS)

Shih, Chun-Hsing; Wang, Jhong-Sheng

2009-01-01

This paper presents a new, physical threshold voltage model to solve the ambiguity in determining the threshold voltage of double-gate (DG) MOSFETs. To avoid the difficulties of the conventional 2ψ B model in nearly undoped DG MOSFETs, this study proposes to define the on–off switching based on the actual roles of the drift and diffusion components in the total drain current. The drift current strongly enhances beyond the threshold voltage, while the diffusion current plays a major role in the subthreshold. The threshold voltage is defined as the drift component that exceeds the diffusion counterpart. From the solutions of Poisson's equation, the drift and diffusion currents of DG MOSFETs are separately formulated to derive the analytical expressions of the threshold voltage and associated threshold current. This model provides a comprehensive description of the switching behavior of DG MOSFET devices, and offers a physical onset threshold current to determine the threshold voltage in practical extraction

Study on the dynamic behavior of a current in cable-in-conduit conductors by using self magnetic field measurements

Energy Technology Data Exchange (ETDEWEB)

Obana, Tetsuhiro, E-mail: obana.tetsuhiro@LHD.nifs.ac.jp [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292, Gifu (Japan); Takahata, Kazuya; Hamaguchi, Shinji; Imagawa, Shinsaku; Mito, Toshiyuki [National Institute for Fusion Science, 322-6 Oroshi, Toki 509-5292, Gifu (Japan); Kizu, Kaname; Murakami, Haruyuki; Yoshida, Kiyoshi [Japan Atomic Energy Agency, Ibaraki (Japan)

2011-10-15

In order to understand the current behavior inside a cable-in-conduit conductor (CICC), self magnetic field measurements on the CICC were conducted. A prototype NbTi CICC, the configuration of which is a racket shape, for JT-60SA EF coil was used as a short conductor sample. By using Hall sensors arranged around the short conductor sample, the variation in the self magnetic field was measured. Taking into account the measurements, the current behavior inside the CICC was analyzed by using analytical models consisting of line currents. The analytical results indicate that the current distribution in the cross-section of the CICC would be non-uniform before a normal propagation, and the current distribution would be improved after the normal propagation.

Towards Behavioral Reflexion Models

Science.gov (United States)

Ackermann, Christopher; Lindvall, Mikael; Cleaveland, Rance

2009-01-01

Software architecture has become essential in the struggle to manage today s increasingly large and complex systems. Software architecture views are created to capture important system characteristics on an abstract and, thus, comprehensible level. As the system is implemented and later maintained, it often deviates from the original design specification. Such deviations can have implication for the quality of the system, such as reliability, security, and maintainability. Software architecture compliance checking approaches, such as the reflexion model technique, have been proposed to address this issue by comparing the implementation to a model of the systems architecture design. However, architecture compliance checking approaches focus solely on structural characteristics and ignore behavioral conformance. This is especially an issue in Systems-of- Systems. Systems-of-Systems (SoS) are decompositions of large systems, into smaller systems for the sake of flexibility. Deviations of the implementation to its behavioral design often reduce the reliability of the entire SoS. An approach is needed that supports the reasoning about behavioral conformance on architecture level. In order to address this issue, we have developed an approach for comparing the implementation of a SoS to an architecture model of its behavioral design. The approach follows the idea of reflexion models and adopts it to support the compliance checking of behaviors. In this paper, we focus on sequencing properties as they play an important role in many SoS. Sequencing deviations potentially have a severe impact on the SoS correctness and qualities. The desired behavioral specification is defined in UML sequence diagram notation and behaviors are extracted from the SoS implementation. The behaviors are then mapped to the model of the desired behavior and the two are compared. Finally, a reflexion model is constructed that shows the deviations between behavioral design and implementation. This

Transformation of UML Behavioral Diagrams to Support Software Model Checking

Directory of Open Access Journals (Sweden)

Luciana Brasil Rebelo dos Santos

2014-04-01

Full Text Available Unified Modeling Language (UML is currently accepted as the standard for modeling (object-oriented software, and its use is increasing in the aerospace industry. Verification and Validation of complex software developed according to UML is not trivial due to complexity of the software itself, and the several different UML models/diagrams that can be used to model behavior and structure of the software. This paper presents an approach to transform up to three different UML behavioral diagrams (sequence, behavioral state machines, and activity into a single Transition System to support Model Checking of software developed in accordance with UML. In our approach, properties are formalized based on use case descriptions. The transformation is done for the NuSMV model checker, but we see the possibility in using other model checkers, such as SPIN. The main contribution of our work is the transformation of a non-formal language (UML to a formal language (language of the NuSMV model checker towards a greater adoption in practice of formal methods in software development.

Reversible thermal fusing model of carbon black current-limiting thermistors

International Nuclear Information System (INIS)

Martin, James E.; Heaney, Michael B.

2000-01-01

Composites of carbon black particles in polyethylene exhibit an unusually rapid increase in resistivity as the applied electric field is increased, making this material commercially useful as current-limiting thermistors, also known as automatically resettable fuses. In this application the composite is in series with the circuit it is protecting: at low applied voltages the circuit is the load, but at high applied voltages the composite becomes the load, limiting the current to the circuit. We present a simple model of this behavior in terms of a network of nonlinear resistors. Each resistor has a resistance that depends explicitly and reversibly on its instantaneous power dissipation. This model predicts that in the soft fusing, or current-limiting, regime, where the current through the composite decreases with increasing voltage, a platelike dissipation instability develops normal to the applied field, in agreement with experimental observations, which is solely due to fluctuations in the microstructure

Quantifying and Disaggregating Consumer Purchasing Behavior for Energy Systems Modeling

Science.gov (United States)

Consumer behaviors such as energy conservation, adoption of more efficient technologies, and fuel switching represent significant potential for greenhouse gas mitigation. Current efforts to model future energy outcomes have tended to use simplified economic assumptions ...

A Possible Minimum Toy Model with Negative Differential Capacitance for Self-sustained Current Oscillation

International Nuclear Information System (INIS)

Xiong Gang; Sun Zhouzhou; Wang Xiangrong

2007-01-01

We generalize a simple model for superlattices to include the effect of differential capacitance. It is shown that the model always has a stable steady-state solution (SSS) if all differential capacitances are positive. On the other hand, when negative differential capacitance is included, the model can have no stable SSS and be in a self-sustained current oscillation behavior. Therefore, we find a possible minimum toy model with both negative differential resistance and negative differential capacitance which can include the phenomena of both self-sustained current oscillation and I-V oscillation of stable SSSs.

Modeling Bubble Flow and Current Density Distribution in an Alkaline Electrolysis Cell

Directory of Open Access Journals (Sweden)

Ravichandra S. Jupudi

2009-12-01

Full Text Available The effect of bubbles on the current density distribution over the electrodes of an alkaline electrolyzer cell is studied using a two-dimensional computational fluid dynamics model. Model includes Eulerian-Eulerian two-phase flow methodology to model the multiphase flow of Hydrogen and Oxygen with water and the behavior of each phase is accounted for using first principle. Hydrogen/Oxygen evolution, flow field and current density distribution are incorporated in the model to account for the complicated physics involved in the process. Fluent 6.2 is used to solve two-phase flow and electrochemistry is incorporated using UDF (User Defined Function feature of Fluent. Model is validated with mesh refinement study and by comparison with experimental measurements. Model is found to replicate the effect of cell voltage and inter-electrode gap (distance between the electrodes on current density accurately. Further, model is found to capture the existence of optimum cell height. The validated model is expected to be a very useful tool in the design and optimization of alkaline electrolyzer cells.

Modeling human behaviors and reactions under dangerous environment.

Science.gov (United States)

Kang, J; Wright, D K; Qin, S F; Zhao, Y

2005-01-01

This paper describes the framework of a real-time simulation system to model human behavior and reactions in dangerous environments. The system utilizes the latest 3D computer animation techniques, combined with artificial intelligence, robotics and psychology, to model human behavior, reactions and decision making under expected/unexpected dangers in real-time in virtual environments. The development of the system includes: classification on the conscious/subconscious behaviors and reactions of different people; capturing different motion postures by the Eagle Digital System; establishing 3D character animation models; establishing 3D models for the scene; planning the scenario and the contents; and programming within Virtools Dev. Programming within Virtools Dev is subdivided into modeling dangerous events, modeling character's perceptions, modeling character's decision making, modeling character's movements, modeling character's interaction with environment and setting up the virtual cameras. The real-time simulation of human reactions in hazardous environments is invaluable in military defense, fire escape, rescue operation planning, traffic safety studies, and safety planning in chemical factories, the design of buildings, airplanes, ships and trains. Currently, human motion modeling can be realized through established technology, whereas to integrate perception and intelligence into virtual human's motion is still a huge undertaking. The challenges here are the synchronization of motion and intelligence, the accurate modeling of human's vision, smell, touch and hearing, the diversity and effects of emotion and personality in decision making. There are three types of software platforms which could be employed to realize the motion and intelligence within one system, and their advantages and disadvantages are discussed.

An information-motivation-behavioral skills model of adherence to antiretroviral therapy.

Science.gov (United States)

Fisher, Jeffrey D; Fisher, William A; Amico, K Rivet; Harman, Jennifer J

2006-07-01

HIV-positive persons who do not maintain consistently high levels of adherence to often complex and toxic highly active antiretroviral therapy (HAART) regimens may experience therapeutic failure and deterioration of health status and may develop multidrug-resistant HIV that can be transmitted to uninfected others. The current analysis conceptualizes social and psychological determinants of adherence to HAART among HIV-positive individuals. The authors propose an information-motivation-behavioral skills (IMB) model of HAART adherence that assumes that adherence-related information, motivation, and behavioral skills are fundamental determinants of adherence to HAART. According to the model, adherence-related information and motivation work through adherence-related behavioral skills to affect adherence to HAART. Empirical support for the IMB model of adherence is presented, and its application in adherence-promotion intervention efforts is discussed.

Current transformer model with hysteresis for improving the protection response in electrical transmission systems

Science.gov (United States)

Matussek, Robert; Dzienis, Cezary; Blumschein, Jörg; Schulte, Horst

2014-12-01

In this paper, a generic enhanced protection current transformer (CT) model with saturation effects and transient behavior is presented. The model is used for the purpose of analysis and design of power system protection algorithms. Three major classes of protection CT have been modeled which all take into account the nonlinear inductance with remanence effects. The transient short-circuit currents in power systems are simulated under CT saturation condition. The response of a common power system protection algorithm with respect to robustness to nominal parameter variations and sensitivity against maloperation is demonstrated by simulation studies.

Current transformer model with hysteresis for improving the protection response in electrical transmission systems

International Nuclear Information System (INIS)

Matussek, Robert; Dzienis, Cezary; Blumschein, Jörg; Schulte, Horst

2014-01-01

In this paper, a generic enhanced protection current transformer (CT) model with saturation effects and transient behavior is presented. The model is used for the purpose of analysis and design of power system protection algorithms. Three major classes of protection CT have been modeled which all take into account the nonlinear inductance with remanence effects. The transient short-circuit currents in power systems are simulated under CT saturation condition. The response of a common power system protection algorithm with respect to robustness to nominal parameter variations and sensitivity against maloperation is demonstrated by simulation studies

Modeling taxi driver anticipatory behavior

NARCIS (Netherlands)

Zheng, Zhong; Rasouli, S.; Timmermans, H.J.P.

2018-01-01

As part of a wider behavioral agent-based model that simulates taxi drivers’ dynamic passenger-finding behavior under uncertainty, we present a model of strategic behavior of taxi drivers in anticipation of substantial time varying demand at locations such as airports and major train stations. The

Behavioral models of tinnitus and hyperacusis in animals

Directory of Open Access Journals (Sweden)

Sarah H Hayes

2014-09-01

Full Text Available The phantom perception of tinnitus and reduced sound level tolerance associated with hyperacusis, have a high comorbidity and can be debilitating conditions for which there are no widely accepted treatments. One factor limiting the development of treatments for tinnitus and hyperacusis is the lack of reliable animal behavioral models of these disorders. Therefore, the purpose of this review is to highlight the current animal models of tinnitus and hyperacusis, and to detail the advantages and disadvantages of each paradigm. To date, this is the first review to include models of both tinnitus and hyperacusis.

Quark model calculations of current correlators in the nonperturbative domain

International Nuclear Information System (INIS)

Celenza, L.S.; Shakin, C.M.; Sun, W.D.

1995-01-01

The authors study the vector-isovector current correlator in this work, making use of a generalized Nambu-Jona-Lasinio (NJL) model. In their work, the original NJL model is extended to describe the coupling of the quark-antiquark states to the two-pion continuum. Further, a model for confinement is introduced that is seen to remove the nonphysical cuts that appear in various amplitudes when the quark and antiquark go on mass shell. Quite satisfactory results are obtained for the correlator. The authors also use the correlator to define a T-matrix for confined quarks and discuss a rho-dominance model for that T-matrix. It is also seen that the Bethe-Salpeter equation that determines the rho mass (in the absence of the coupling to the two-pion continuum) has more satisfactory behavior in the generalized model than in the model without confinement. That improved behavior is here related to the absence of the q bar q cut in the basic quark-loop integral of the generalized model. In this model, it is seen how one may work with both quark and hadron degrees of freedom, with only the hadrons appearing as physical particles. 12 refs., 16 figs., 1 tab

Leaving an Abusive Dating Relationship: A Prospective Analysis of the Investment Model and Theory of Planned Behavior.

Science.gov (United States)

Edwards, Katie M; Gidycz, Christine A; Murphy, Megan J

2015-10-01

The purpose of the current study was to build on the existing literature to better understand young women's leaving processes in abusive dating relationships using a prospective design. Two social psychological models-the investment model and theory of planned behavior-were tested. According to the investment model, relationship continuation is predicted by commitment, which is a function of investment, satisfaction, and low quality of alternatives. The theory of planned behavior asserts that a specific behavior is predicted by an individual's intention to use a behavior, which is a function of the individual's attitudes toward the behavior, the subjective norms toward the behavior, and the individual's perceived behavioral control over the behavior. College women (N = 169 young women in abusive relatinships) completed surveys at two time points, approximately 4 months apart, to assess initially for the presence of intimate partner violence (IPV) in a current relationship and investment model and theory of planned behavior variables; the purpose of the 4-month follow-up session was to determine if women had remained in or terminated their abusive relationship. Path analytic results demonstrated that both the theory of planned behavior and investment models were good fits to the data in prospectively predicting abused women's stay/leave decisions. However, the theory of planned behavior was a better fit to the data than the investment model. Implications for future research and intervention are discussed. © The Author(s) 2014.

Social behavior in the "Age of Empathy"?-A social scientist's perspective on current trends in the behavioral sciences.

Science.gov (United States)

Matusall, Svenja

2013-01-01

Recently, several behavioral sciences became increasingly interested in investigating biological and evolutionary foundations of (human) social behavior. In this light, prosocial behavior is seen as a core element of human nature. A central role within this perspective plays the "social brain" that is not only able to communicate with the environment but rather to interact directly with other brains via neuronal mind reading capacities such as empathy. From the perspective of a sociologist, this paper investigates what "social" means in contemporary behavioral and particularly brain sciences. It will be discussed what "social" means in the light of social neuroscience and a glance into the history of social psychology and the brain sciences will show that two thought traditions come together in social neuroscience, combining an individualistic and an evolutionary notion of the "social." The paper concludes by situating current research on prosocial behavior in broader social discourses about sociality and society, suggesting that to naturalize prosocial aspects in human life is a current trend in today's behavioral sciences and beyond.

RETHINKING ECONOMICS-OF-CRIME MODEL OF TAX COMPLIANCE FROM BEHAVIORAL PERSPECTIVE APPLIED TO ROMANIAN CASE

Directory of Open Access Journals (Sweden)

Elena Ana Iancu(Nechita

2016-12-01

Full Text Available Present paper tackles several research paradigms regarding tax compliance behavior that have been used to understand tax evasion phenomenon and tax avoidance behavior of the taxpayer. These notions have been studied by numerous researchers all over the world as phenomenon of tax evasion has a debating issue on every state agenda for several decades. First economic model of tax compliance behavior was developed in the early 1970s and since then researchers improved the model adding new elements from sociology, psychology, legal studies, finance, game theory, neurosciences, econophysics and others. This paper presents the most important developments of current theories regarding tax compliance behavior starting from the economics-of-crime model,till the 'slippery slope framework ', and more. It creates the premises for a Romanian model of tax compliance behavior according to national characteristics regarding taxpayers attitude towards tax avoidance, risk appetite or aversion upon enforcement of law through punishment and penalty, taxpayers’ trust in authority’s efficient spending of tax collected revenue to public budget and personal beliefs regarding notions like morality, cheating, honesty, social responsibility, loyalty, patriotism, civic duty, guilt, fairness, reciprocity or financial incentives. Recent models of tax compliance behavior underline the importance of the dynamics between all the actors involved in the fiscal system such as government, tax authorities, tax consultants and accountants and the behavior of all other taxpayers as a whole. Current research trends believe that these are mutually related. Another important aspect regarding taxpayer’s attitude towards tax avoidance is its own motivation to voluntarily pay taxes driven by intrinsic beliefs or by fear of penalty coming from enforcement of laws. On the contrary, other taxpayers choose to assume an extra share of risk and decide to avoid taxes hiding in anonymity of

Condition monitoring with wind turbine SCADA data using Neuro-Fuzzy normal behavior models

DEFF Research Database (Denmark)

Schlechtingen, Meik; Santos, Ilmar

2012-01-01

System (ANFIS) models are employed to learn the normal behavior in a training phase, where the component condition can be considered healthy. In the application phase the trained models are applied to predict the target signals, e.g. temperatures, pressures, currents, power output, etc. The behavior......This paper presents the latest research results of a project that focuses on normal behavior models for condition monitoring of wind turbines and their components, via ordinary Supervisory Control And Data Acquisition (SCADA) data. In this machine learning approach Adaptive Neuro-Fuzzy Interference...... of the prediction error is used as an indicator for normal and abnormal behavior, with respect to the learned behavior. The advantage of this approach is that the prediction error is widely decoupled from the typical fluctuations of the SCADA data caused by the different turbine operational modes. To classify...

Modeling Unidirectional Pedestrian Movement: An Investigation of Diffusion Behavior in the Built Environment

Directory of Open Access Journals (Sweden)

Ying Liu

2015-01-01

Full Text Available Unidirectional pedestrian movement is a special phenomenon in the evacuation process of large public buildings and urban environments at pedestrian scale. Several macroscopic models for collective behaviors have been built to predict pedestrian flow. However, current models do not explain the diffusion behavior in pedestrian crowd movement, which can be important in representing spatial-temporal crowd density differentiation in the movement process. This study builds a macroscopic model for describing crowd diffusion behavior and evaluating unidirectional pedestrian flow. The proposed model employs discretization of time and walking speed in geometric distribution to calculate downstream pedestrian crowd flow and analyze movement process based on upstream number of pedestrians and average walking speed. The simulated results are calibrated with video observation data in a baseball stadium to verify the model precision. Statistical results have verified that the proposed pedestrian diffusion model could accurately describe pedestrian macromovement behavior within the margin of error.

Swimming Behavior and Flow Geometry: A Fluid Mechanical Study of the Feeding Currents in Calanoid Copepods

Science.gov (United States)

Jiang, Houshuo; Meneveau, Charles; Osborn, Thomas R.

2003-11-01

Copepods are small crustaceans living in oceans and fresh waters and play an important role in the marine and freshwater food webs. As they are the biggest biomass in the oceans some call them "the insects of the sea". Previous laboratory observations have shown that the fluid mechanical phenomena occurring at copepod body scale are crucial for the survival of copepods. One of the interesting phenomena is that many calanoid copepods display various behaviors to create the feeding currents for the purpose of capturing food particles. We have developed a fluid mechanical model to study the feeding currents. The model is a self-propelled body model in that the Navier-Stokes equations are properly coupled with the dynamic equations for the copepod's body. The model has been solved both analytically using the Stokes approximation with a spherical body shape and numerically using CFD with a realistic body shape.

Dynamic behavior of HTSC opening switch models controlled by short over-critical current pulses

International Nuclear Information System (INIS)

Agafonov, A.V.; Krastelev, E.G.; Voronin, V.S.

1999-01-01

We present results of experimental research of dynamical properties of thin films of YBa 2 Cu 3 O 7 HTSC-switch models under action of short overcritical current pulses to test this method of control of fast high-power opening switches for accelerator applications

Current and ideal skin tone: Associations with tanning behavior among sexual minority men.

Science.gov (United States)

Klimek, Patrycja; Lamb, Kalina M; Nogg, Kelsey A; Rooney, Benjamin M; Blashill, Aaron J

2018-06-01

Sexual minority men have high rates of skin cancer, yet little is known about skin cancer risk behaviors in this population. It was hypothesized that current skin tone would moderate the association between darker ideals and tanning behaviors. Data were collected online from 231 sexual minority men in San Diego, United States of America, with a mean age of 24.66 (SD = 5.44). Ideal and current skin tone ratings and indoor and outdoor tanning behaviors were assessed. Darker ideals were significantly associated with increased indoor and outdoor tanning. The effect of darker ideals on tanning was strongest among individuals with lighter current skin tone, indicating a significant interaction. Sexual minority men whose perceived skin tone did not match their ideal were more likely to engage in skin cancer risk behaviors. Future skin cancer prevention programs aimed at sexual minority men may consider techniques that modify ideal skin tone internalization. Copyright © 2018 Elsevier Ltd. All rights reserved.

Current Hormonal Contraceptive Use Predicts Female Extra-Pair and Dyadic Sexual Behavior: Evidence Based on Czech National Survey Data

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Kateřina Klapilová

2014-01-01

Full Text Available Data from 1155 Czech women (493 using oral contraception, 662 non-users, obtained from the Czech National Survey of Sexual Behavior, were used to investigate evolutionary-based hypotheses concerning the predictive value of current oral contraceptive (OC use on extra-pair and dyadic (in-pair sexual behavior of coupled women. Specifically, the aim was to determine whether current OC use was associated with lower extra-pair and higher in-pair sexual interest and behavior, because OC use suppresses cyclical shifts in mating psychology that occur in normally cycling women. Zero-inflated Poisson (ZIP regression and negative binomial models were used to test associations between OC use and these sexual measures, controlling for other relevant predictors (e.g., age, parity, in-pair sexual satisfaction, relationship length. The overall incidence of having had an extra-pair partner or one-night stand in the previous year was not related to current OC use (the majority of the sample had not. However, among the women who had engaged in extra-pair sexual behavior, OC users had fewer one-night stands than non-users, and tended to have fewer partners, than non-users. OC users also had more frequent dyadic intercourse than non-users, potentially indicating higher commitment to their current relationship. These results suggest that suppression of fertility through OC use may alter important aspects of female sexual behavior, with potential implications for relationship functioning and stability.

An approach to modeling operator's cognitive behavior using artificial intelligence techniques in emergency operating event sequences

International Nuclear Information System (INIS)

Cheon, Se Woo; Sur, Sang Moon; Lee, Yong Hee; Park, Young Taeck; Moon, Sang Joon

1994-01-01

Computer modeling of an operator's cognitive behavior is a promising approach for the purpose of human factors study and man-machine systems assessment. In this paper, the states of the art in modeling operator behavior and the current status in developing an operator's model (MINERVA - NPP) are presented. The model is constructed as a knowledge-based system of a blackboard framework and is simulated based on emergency operating procedures

Magnetic field behavior of current steps in long Josephson junctions

International Nuclear Information System (INIS)

Costabile, G.; Cucolo, A.M.; Pace, S.; Parmentier, R.D.; Savo, B.; Vaglio, R.

1980-01-01

The zero-field steps, or dc current singularities, in the current-voltage characteristics of long Josephson tunnel junctions, first reported by Chen et al., continue to attract research interest both because their study can provide fundamental information on the dynamics of fluxons in such junctions and because they are accompanied by the emission of microwave radiation from the junction, which may be exploitable in practical oscillator applications. The purpose of this paper is to report some experimental observations of the magnetic field behavior of the steps in junctions fabricated in our Laboratory and to offer a qualitative explanation for this behavior. Measurements have been made both for very long (L >> lambdasub(J)) and for slightly long (L approx. >= lambdasub(J)) junctions with a view toward comparing our results with those of other workers. (orig./WRI)

Understanding HIV Transmission Risk Behavior Among HIV-Infected South Africans Receiving Antiretroviral Therapy: An Information—Motivation—Behavioral Skills Model Analysis

Science.gov (United States)

Kiene, Susan M.; Fisher, William A.; Shuper, Paul A.; Cornman, Deborah H.; Christie, Sarah; MacDonald, Susan; Pillay, Sandy; Mahlase, Gethwana; Fisher, Jeffrey D.

2014-01-01

The current study applied the Information—Motivation—Behavioral Skills (IMB) model (J. D. Fisher & Fisher, 1992; W. A. Fisher & Fisher, 1993) to identify factors associated with HIV transmission risk behavior among HIV-infected South Africans receiving antiretroviral therapy (ART), a population of considerable significance for curtailing, or maintaining, South Africa’s generalized HIV epidemic. HIV prevention information, HIV prevention motivation, HIV prevention behavioral skills, and HIV transmission risk behavior were assessed in a sample of 1,388 South Africans infected with HIV and receiving ART in 16 clinics in KwaZulu-Natal, South Africa. Results confirmed the assumptions of the IMB model and demonstrated that HIV prevention information and HIV prevention motivation work through HIV prevention behavioral skills to affect HIV transmission risk behavior in this population. Subanalyses confirmed these relationships for HIV transmission risk behavior overall and for HIV transmission risk behavior with partners perceived to be HIV-negative or HIV-status unknown. A consistent pattern of gender differences showed that for men, HIV prevention information and HIV prevention motivation may have direct links with HIV preventive behavior, while for women, the effects of HIV prevention information and HIV prevention motivation work through HIV prevention behavioral skills to affect HIV preventive behavior. These IMB model-based findings suggest directions for HIV prevention interventions with South African men and women living with HIV and on ART as an important component of overall strategies to contain South Africa’s generalized HIV epidemic. PMID:23477576

Understanding HIV transmission risk behavior among HIV-infected South Africans receiving antiretroviral therapy: an information--motivation--behavioral skills model analysis.

Science.gov (United States)

Kiene, Susan M; Fisher, William A; Shuper, Paul A; Cornman, Deborah H; Christie, Sarah; Macdonald, Susan; Pillay, Sandy; Mahlase, Gethwana; Fisher, Jeffrey D

2013-08-01

The current study applied the Information-Motivation-Behavioral Skills (IMB) model (Fisher & Fisher, 1992; Fisher & Fisher, 1993) to identify factors associated with human immunodeficiency virus (HIV) transmission risk behavior among HIV-infected South Africans receiving antiretroviral therapy (ART), a population of considerable significance for curtailing, or maintaining, South Africa's generalized HIV epidemic. HIV prevention information, HIV prevention motivation, HIV prevention behavioral skills, and HIV transmission risk behavior were assessed in a sample of 1,388 South Africans infected with HIV and receiving ART in 16 clinics in KwaZulu-Natal, South Africa. Findings confirmed the assumptions of the IMB model and demonstrated that HIV prevention information and HIV prevention motivation work through HIV prevention behavioral skills to affect HIV transmission risk behavior in this population. Subanalyses confirmed these relationships for HIV transmission risk behavior overall and for HIV transmission risk behavior with partners perceived to be HIV-negative or HIV-status unknown. A consistent pattern of gender differences showed that for men, HIV prevention information and HIV prevention motivation may have direct links with HIV preventive behavior, whereas for women, the effect of HIV prevention motivation works through HIV prevention behavioral skills to affect HIV preventive behavior. These IMB model-based findings suggest directions for HIV prevention interventions with South African men and women living with HIV and on ART as an important component of overall strategies to contain South Africa's generalized HIV epidemic. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Experimental studies of coaxial plasma gun current

International Nuclear Information System (INIS)

Price, D.W.

1988-01-01

In this investigation of a coaxial plasma gun, plasma sheath currents and related behavior are examined. Plasma behavior in the gun affects gun characteristics. Plasma gun applications are determined by the plasma behavior. The AFWL PUFF capacitor bank (72 μF, 29 nH, 120 kV) drives the plasma gun using a deuterium fill gas. The gas breakdown site is isolated from the dielectric/vacuum interface in the AFWL system. Two gas values deliver gas in the system. The first delivers gas from the gun breech and the second optional valve delivers gas to the gun muzzle. Currents and voltages are measured by Rogowski coils, B probes and capacitive voltage probes. A O-D slug model is used to predict the current, inductance, gun voltage and plasma sheath velocity. The slug model assumes the sheath transits the gun with all mass in the sheath. In the snowplow mode, the plasma sheath is thin with a sharp current rise and drop. Our system operated in a transition mode between the snowplow and deflagration modes with early snowplow behavior and late deflagration behavior. Neutrons are produced in a plasma pinch at the gun muzzle, indicating snowplow behavior. The slug theory models overall gun behavior to experimental accuracy. Experimental results are compared to four theories for plasma sheath velocities: the Alfven collisionally limited model, the Rosenbluth model, the Fishbine saturated model and a single particle drift model. Experimental velocities vary from 10 5 to 10 6 m/s. Only the single particle drift and the slug model calculations are of the right magnitude (8 x 10 5 m/s). The Fishbine and the Rosenbluth models predict slower velocities (2 x 10 5 m/s). The Alfven model is not applicable to this system

Fractional Modeling of the AC Large-Signal Frequency Response in Magnetoresistive Current Sensors

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Sergio Iván Ravelo Arias

2013-12-01

Full Text Available Fractional calculus is considered when derivatives and integrals of non-integer order are applied over a specific function. In the electrical and electronic domain, the transfer function dependence of a fractional filter not only by the filter order n, but additionally, of the fractional order α is an example of a great number of systems where its input-output behavior could be more exactly modeled by a fractional behavior. Following this aim, the present work shows the experimental ac large-signal frequency response of a family of electrical current sensors based in different spintronic conduction mechanisms. Using an ac characterization set-up the sensor transimpedance function  is obtained considering it as the relationship between sensor output voltage and input sensing current,[PLEASE CHECK FORMULA IN THE PDF]. The study has been extended to various magnetoresistance sensors based in different technologies like anisotropic magnetoresistance (AMR, giant magnetoresistance (GMR, spin-valve (GMR-SV and tunnel magnetoresistance (TMR. The resulting modeling shows two predominant behaviors, the low-pass and the inverse low-pass with fractional index different from the classical integer response. The TMR technology with internal magnetization offers the best dynamic and sensitivity properties opening the way to develop actual industrial applications.

Stability analysis of direct current control in current source rectifier

DEFF Research Database (Denmark)

Lu, Dapeng; Wang, Xiongfei; Blaabjerg, Frede

2017-01-01

Current source rectifier with high switching frequency has a great potential for improving the power efficiency and power density in ac-dc power conversion. This paper analyzes the stability of direct current control based on the time delay effect. Small signal model including dynamic behaviors...

Theory of Planned Behavior in the Classroom: An Examination of the Instructor Confirmation-Interaction Model

Science.gov (United States)

Burns, Michael E.; Houser, Marian L.; Farris, Kristen LeBlanc

2018-01-01

The current study utilizes the theory of planned behavior (Ajzen "Organizational Behavior and Human Decision Processes," 50, 179-211 Ajzen 1991) to examine an instructor confirmation-interaction model in the instructional communication context to discover a means by which instructors might cultivate positive student attitudes and…

Plasma-induced evolution behavior of space-charge-limited current for multiple-needle cathodes

International Nuclear Information System (INIS)

Li Limin; Liu Lie; Zhang Jun; Wen Jianchun; Liu Yonggui; Wan Hong

2009-01-01

Properties of the plasma and beam flow produced by tufted carbon fiber cathodes in a diode powered by a ∼500 kV, ∼400 ns pulse are investigated. Under electric fields of 230-260 kV cm -1 , the electron current density was in the range 210-280 A cm -2 , and particularly at the diode gap of 20 mm, a maximum beam power density of about 120 MW cm -2 was obtained. It was found that space-charge-limited current exhibited an evolution behavior as the accelerating pulse proceeded. There exists a direct relation between the movement of plasma within the diode and the evolution of space-charge-limited current. Initially in the accelerating pulse, the application of strong electric fields caused the emission sites to explode, forming cathode flares or plasma spots, and in this stage the space-charge-limited current was approximately described by a multiple-needle cathode model. As the pulse proceeded, these plasma spots merged and expanded towards the anode, thus increasing the emission area and shortening the diode gap, and the corresponding space-charge-limited current followed a planar cathode model. Finally, the space-charge-limited current is developed from a unipolar flow into a bipolar flow as a result of the appearance of anode plasma. In spite of the nonuniform distribution of cathode plasma, the cross-sectional uniformity of the extracted electron beam is satisfactory. The plasma expansion within the diode is found to be a major factor in the diode perveance growth and instability. These results show that these types of cathodes can offer promising applications for high-power microwave tubes.

Models accounting for intention-behavior discordance in the physical activity domain: a user's guide, content overview, and review of current evidence.

Science.gov (United States)

Rhodes, Ryan E; Yao, Christopher A

2015-02-07

There is a growing concern among researchers with the limited effectiveness and yet subsequent stagnation of theories applied to physical activity (PA). One of the most highlighted areas of concern is the established gap between intention and PA, yet the considerable use of models that assume intention is the proximal antecedent of PA. The objective of this review was to: 1) provide a guide and thematic analysis of the available models that include constructs that address intention-behavior discordance and 2) highlight the evidence for these structures in the PA domain. A literature search was conducted among 13 major databases to locate relevant models and PA studies published before August 2014. Sixteen models were identified and nine overall themes for post-intentional constructs were created. Of the 16 models, eight were applied to 36 PA studies. Early evidence supported maintenance self-efficacy, behavioral regulation strategies, affective judgments, perceived control/opportunity, habit, and extraversion as reliable predictors of post-intention PA. Several intention-behavior discordance models exist within the literature, but are not used frequently. Further efforts are needed to test these models, preferably with experimental designs.

Evaluating Behavioral Economic Models of Heavy Drinking Among College Students.

Science.gov (United States)

Acuff, Samuel F; Soltis, Kathryn E; Dennhardt, Ashley A; Berlin, Kristoffer S; Murphy, James G

2018-05-14

Heavy drinking among college students is a significant public health concern that can lead to profound social and health consequences, including alcohol use disorder. Behavioral economics posits that low future orientation and high valuation of alcohol (alcohol demand) combined with deficits in alternative reinforcement increase the likelihood of alcohol misuse (Bickel et al., 2011). Despite this, no study has examined the incremental utility of all three variables simultaneously in a comprehensive model METHOD: The current study uses structural equation modeling to test the associations between behavioral economic variables - alcohol demand (latent), future orientation (measured with a delay discounting task and the Consideration of Future Consequences (CFC) scale), and proportionate substance-related reinforcement - and alcohol consumption and problems among 393 heavy drinking college students. Two models are tested: 1) an iteration of the reinforcer pathology model that includes an interaction between future orientation and alcohol demand; and 2) an alternative model evaluating the interconnectedness of behavioral economic variables in predicting problematic alcohol use RESULTS: The interaction effects in model 1 were nonsignificant. Model 2 suggests that greater alcohol demand and proportionate substance-related reinforcement is associated with greater alcohol consumption and problems. Further, CFC was associated with alcohol-related problems and lower proportionate substance-related reinforcement but was not significantly associated with alcohol consumption or alcohol demand. Finally, greater proportionate substance-related reinforcement was associated with greater alcohol demand CONCLUSIONS: Our results support the validity of the behavioral economic reinforcer pathology model as applied to young adult heavy drinking. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Capabilities of current wildfire models when simulating topographical flow

Science.gov (United States)

Kochanski, A.; Jenkins, M.; Krueger, S. K.; McDermott, R.; Mell, W.

2009-12-01

Accurate predictions of the growth, spread and suppression of wild fires rely heavily on the correct prediction of the local wind conditions and the interactions between the fire and the local ambient airflow. Resolving local flows, often strongly affected by topographical features like hills, canyons and ridges, is a prerequisite for accurate simulation and prediction of fire behaviors. In this study, we present the results of high-resolution numerical simulations of the flow over a smooth hill, performed using (1) the NIST WFDS (WUI or Wildland-Urban-Interface version of the FDS or Fire Dynamic Simulator), and (2) the LES version of the NCAR Weather Research and Forecasting (WRF-LES) model. The WFDS model is in the initial stages of development for application to wind flow and fire spread over complex terrain. The focus of the talk is to assess how well simple topographical flow is represented by WRF-LES and the current version of WFDS. If sufficient progress has been made prior to the meeting then the importance of the discrepancies between the predicted and measured winds, in terms of simulated fire behavior, will be examined.

Hysteresis-controlled instability waves in a scale-free driven current sheet model

Directory of Open Access Journals (Sweden)

V. M. Uritsky

2005-01-01

Full Text Available Magnetospheric dynamics is a complex multiscale process whose statistical features can be successfully reproduced using high-dimensional numerical transport models exhibiting the phenomenon of self-organized criticality (SOC. Along this line of research, a 2-dimensional driven current sheet (DCS model has recently been developed that incorporates an idealized current-driven instability with a resistive MHD plasma system (Klimas et al., 2004a, b. The dynamics of the DCS model is dominated by the scale-free diffusive energy transport characterized by a set of broadband power-law distribution functions similar to those governing the evolution of multiscale precipitation regions of energetic particles in the nighttime sector of aurora (Uritsky et al., 2002b. The scale-free DCS behavior is supported by localized current-driven instabilities that can communicate in an avalanche fashion over arbitrarily long distances thus producing current sheet waves (CSW. In this paper, we derive the analytical expression for CSW speed as a function of plasma parameters controlling local anomalous resistivity dynamics. The obtained relation indicates that the CSW propagation requires sufficiently high initial current densities, and predicts a deceleration of CSWs moving from inner plasma sheet regions toward its northern and southern boundaries. We also show that the shape of time-averaged current density profile in the DCS model is in agreement with steady-state spatial configuration of critical avalanching models as described by the singular diffusion theory of the SOC. Over shorter time scales, SOC dynamics is associated with rather complex spatial patterns and, in particular, can produce bifurcated current sheets often seen in multi-satellite observations.

Use of multiscale zirconium alloy deformation models in nuclear fuel behavior analysis

Energy Technology Data Exchange (ETDEWEB)

Montgomery, Robert, E-mail: robert.montgomery@pnnl.gov [Pacific Northwest National Laboratory (United States); Tomé, Carlos, E-mail: tome@lanl.gov [Los Alamos National Laboratory (United States); Liu, Wenfeng, E-mail: wenfeng.liu@anatech.com [ANATECH Corporation (United States); Alankar, Alankar, E-mail: alankar.alankar@iitb.ac.in [Indian Institute of Technology Bombay (India); Subramanian, Gopinath, E-mail: gopinath.subramanian@usm.edu [University of Southern Mississippi (United States); Stanek, Christopher, E-mail: stanek@lanl.gov [Los Alamos National Laboratory (United States)

2017-01-01

Accurate prediction of cladding mechanical behavior is a key aspect of modeling nuclear fuel behavior, especially for conditions of pellet-cladding interaction (PCI), reactivity-initiated accidents (RIA), and loss of coolant accidents (LOCA). Current approaches to fuel performance modeling rely on empirical constitutive models for cladding creep, growth and plastic deformation, which are limited to the materials and conditions for which the models were developed. To improve upon this approach, a microstructurally-based zirconium alloy mechanical deformation analysis capability is being developed within the United States Department of Energy Consortium for Advanced Simulation of Light Water Reactors (CASL). Specifically, the viscoplastic self-consistent (VPSC) polycrystal plasticity modeling approach, developed by Lebensohn and Tomé [1], has been coupled with the BISON engineering scale fuel performance code to represent the mechanistic material processes controlling the deformation behavior of light water reactor (LWR) cladding. A critical component of VPSC is the representation of the crystallographic nature (defect and dislocation movement) and orientation of the grains within the matrix material and the ability to account for the role of texture on deformation. A future goal is for VPSC to obtain information on reaction rate kinetics from atomistic calculations to inform the defect and dislocation behavior models described in VPSC. The multiscale modeling of cladding deformation mechanisms allowed by VPSC far exceed the functionality of typical semi-empirical constitutive models employed in nuclear fuel behavior codes to model irradiation growth and creep, thermal creep, or plasticity. This paper describes the implementation of an interface between VPSC and BISON and provides initial results utilizing the coupled functionality.

Model for behavior observation training programs

International Nuclear Information System (INIS)

Berghausen, P.E. Jr.

1987-01-01

Continued behavior observation is mandated by ANSI/ANS 3.3. This paper presents a model for behavior observation training that is in accordance with this standard and the recommendations contained in US NRC publications. The model includes seventeen major topics or activities. Ten of these are discussed: Pretesting of supervisor's knowledge of behavior observation requirements, explanation of the goals of behavior observation programs, why behavior observation training programs are needed (legal and psychological issues), early indicators of emotional instability, use of videotaped interviews to demonstrate significant psychopathology, practice recording behaviors, what to do when unusual behaviors are observed, supervisor rationalizations for noncompliance, when to be especially vigilant, and prevention of emotional instability

On tridimensional rip current modeling

Science.gov (United States)

Marchesiello, Patrick; Benshila, Rachid; Almar, Rafael; Uchiyama, Yusuke; McWilliams, James C.; Shchepetkin, Alexander

2015-12-01

Do lateral shear instabilities of nearshore circulation account for a substantial part of Very Low-Frequency (VLF) variability? If yes, it would promote stirring and mixing of coastal waters and surf-shelf exchanges. Another question is whether tridimensional transient processes are important for instability generation. An innovative modeling system with tridimensional wave-current interactions was designed to investigate transient nearshore currents and interactions between nearshore and innershelf circulations. We present here some validation of rip current modeling for the Aquitanian coast of France, using in-situ and remote video sensing. We then proceed to show the benefits of 3D versus 2D (depth-mean flow) modeling of rip currents and their low-frequency variability. It appears that a large part of VLF motions is due to intrinsic variability of the tridimensional flow. 3D models may thus provide a valuable, only marginally more expensive alternative to conventional 2D approaches that miss the vertical flow structure and its nonlinear interaction with the depth-averaged flow.

Tracking the sleep onset process: an empirical model of behavioral and physiological dynamics.

Directory of Open Access Journals (Sweden)

Michael J Prerau

2014-10-01

Full Text Available The sleep onset process (SOP is a dynamic process correlated with a multitude of behavioral and physiological markers. A principled analysis of the SOP can serve as a foundation for answering questions of fundamental importance in basic neuroscience and sleep medicine. Unfortunately, current methods for analyzing the SOP fail to account for the overwhelming evidence that the wake/sleep transition is governed by continuous, dynamic physiological processes. Instead, current practices coarsely discretize sleep both in terms of state, where it is viewed as a binary (wake or sleep process, and in time, where it is viewed as a single time point derived from subjectively scored stages in 30-second epochs, effectively eliminating SOP dynamics from the analysis. These methods also fail to integrate information from both behavioral and physiological data. It is thus imperative to resolve the mismatch between the physiological evidence and analysis methodologies. In this paper, we develop a statistically and physiologically principled dynamic framework and empirical SOP model, combining simultaneously-recorded physiological measurements with behavioral data from a novel breathing task requiring no arousing external sensory stimuli. We fit the model using data from healthy subjects, and estimate the instantaneous probability that a subject is awake during the SOP. The model successfully tracked physiological and behavioral dynamics for individual nights, and significantly outperformed the instantaneous transition models implicit in clinical definitions of sleep onset. Our framework also provides a principled means for cross-subject data alignment as a function of wake probability, allowing us to characterize and compare SOP dynamics across different populations. This analysis enabled us to quantitatively compare the EEG of subjects showing reduced alpha power with the remaining subjects at identical response probabilities. Thus, by incorporating both

Current drinking and health-risk behaviors among male high school students in central Thailand

Directory of Open Access Journals (Sweden)

Pichainarong Natchaporn

2011-04-01

Full Text Available Abstract Background Alcohol drinking is frequently related to behavioral problems, which lead to a number of negative consequences. This study was to evaluate the characteristics of male high school students who drink, the drinking patterns among them, and the associations between current drinking and other health risk behaviors which focused on personal safety, violence-related behaviors, suicide and sexual behaviors. Method A cross-sectional study was conducted to explore current alcohol drinking and health-risk behaviors among male high school students in central Thailand. Five thousand one hundred and eighty four male students were classified into 2 groups according to drinking in the previous 30 days (yes = 631, no = 4,553. Data were collected by self-administered, anonymous questionnaire which consisted of 3 parts: socio-demographic factors, health-risk behaviors and alcohol drinking behavior during the past year from December 2007 to February 2008. Results The results showed that the percent of current drinking was 12.17. Most of them were 15-17 years (50.21%. Socio-demographic factors such as age, educational level, residence, cohabitants, grade point average (GPA, having a part time job and having family members with alcohol/drug problems were significantly associated with alcohol drinking (p Conclusions An increased risk of health-risk behaviors, including driving vehicles after drinking, violence-related behaviors, sad feelings and attempted suicide, and sexual behaviors was higher among drinking students that led to significant health problems. Effective intervention strategies (such as a campaign mentioning the adverse health effects and social consequences to the risk groups, and encouraging parental and community efforts to prevent drinking among adolescents should be implemented to prevent underage drinking and adverse consequences.

Modeling Temporal Behavior in Large Networks: A Dynamic Mixed-Membership Model

Energy Technology Data Exchange (ETDEWEB)

Rossi, R; Gallagher, B; Neville, J; Henderson, K

2011-11-11

Given a large time-evolving network, how can we model and characterize the temporal behaviors of individual nodes (and network states)? How can we model the behavioral transition patterns of nodes? We propose a temporal behavior model that captures the 'roles' of nodes in the graph and how they evolve over time. The proposed dynamic behavioral mixed-membership model (DBMM) is scalable, fully automatic (no user-defined parameters), non-parametric/data-driven (no specific functional form or parameterization), interpretable (identifies explainable patterns), and flexible (applicable to dynamic and streaming networks). Moreover, the interpretable behavioral roles are generalizable, computationally efficient, and natively supports attributes. We applied our model for (a) identifying patterns and trends of nodes and network states based on the temporal behavior, (b) predicting future structural changes, and (c) detecting unusual temporal behavior transitions. We use eight large real-world datasets from different time-evolving settings (dynamic and streaming). In particular, we model the evolving mixed-memberships and the corresponding behavioral transitions of Twitter, Facebook, IP-Traces, Email (University), Internet AS, Enron, Reality, and IMDB. The experiments demonstrate the scalability, flexibility, and effectiveness of our model for identifying interesting patterns, detecting unusual structural transitions, and predicting the future structural changes of the network and individual nodes.

Circulation-based Modeling of Gravity Currents

Science.gov (United States)

Meiburg, E. H.; Borden, Z.

2013-05-01

Atmospheric and oceanic flows driven by predominantly horizontal density differences, such as sea breezes, thunderstorm outflows, powder snow avalanches, and turbidity currents, are frequently modeled as gravity currents. Efforts to develop simplified models of such currents date back to von Karman (1940), who considered a two-dimensional gravity current in an inviscid, irrotational and infinitely deep ambient. Benjamin (1968) presented an alternative model, focusing on the inviscid, irrotational flow past a gravity current in a finite-depth channel. More recently, Shin et al. (2004) proposed a model for gravity currents generated by partial-depth lock releases, considering a control volume that encompasses both fronts. All of the above models, in addition to the conservation of mass and horizontal momentum, invoke Bernoulli's law along some specific streamline in the flow field, in order to obtain a closed system of equations that can be solved for the front velocity as function of the current height. More recent computational investigations based on the Navier-Stokes equations, on the other hand, reproduce the dynamics of gravity currents based on the conservation of mass and momentum alone. We propose that it should therefore be possible to formulate a fundamental gravity current model without invoking Bernoulli's law. The talk will show that the front velocity of gravity currents can indeed be predicted as a function of their height from mass and momentum considerations alone, by considering the evolution of interfacial vorticity. This approach does not require information on the pressure field and therefore avoids the need for an energy closure argument such as those invoked by the earlier models. Predictions by the new theory are shown to be in close agreement with direct numerical simulation results. References Von Karman, T. 1940 The engineer grapples with nonlinear problems, Bull. Am. Math Soc. 46, 615-683. Benjamin, T.B. 1968 Gravity currents and related

Current versus ideal skin tones and tanning behaviors in Caucasian college women.

Science.gov (United States)

Hemrich, Ashley; Pawlow, Laura; Pomerantz, Andrew; Segrist, Dan

2014-01-01

To explore tanning behaviors and whether a discrepancy between current and ideal skin tones exists. The sample included 78 Caucasian women from a mid-sized midwestern university. Data were collected in spring 2012 via a paper questionnaire. Sixty-two percent of the sample regularly engaged in salon tanning at least once per week, with an average frequency of 2.5 visits per week. Thirteen percent endorsed regularly tanning 4 or more times per week, and 26% reported visiting a tanning bed more than once in a 24-hour period. Ninety-four percent wished their current skin tone was darker, and ideal tone was significantly darker than current tone. The data suggest that the young Caucasian women in this sample tend to be dissatisfied with their current skin tone to an extent that leads the majority of them to engage in risky, potentially cancer-causing behavior by either salon tanning or considering tanning in the future as time and finances become available.

Dynamics of edge currents in a linearly quenched Haldane model

Science.gov (United States)

Mardanya, Sougata; Bhattacharya, Utso; Agarwal, Amit; Dutta, Amit

2018-03-01

In a finite-time quantum quench of the Haldane model, the Chern number determining the topology of the bulk remains invariant, as long as the dynamics is unitary. Nonetheless, the corresponding boundary attribute, the edge current, displays interesting dynamics. For the case of sudden and adiabatic quenches the postquench edge current is solely determined by the initial and the final Hamiltonians, respectively. However for a finite-time (τ ) linear quench in a Haldane nanoribbon, we show that the evolution of the edge current from the sudden to the adiabatic limit is not monotonic in τ and has a turning point at a characteristic time scale τ =τ0 . For small τ , the excited states lead to a huge unidirectional surge in the edge current of both edges. On the other hand, in the limit of large τ , the edge current saturates to its expected equilibrium ground-state value. This competition between the two limits lead to the observed nonmonotonic behavior. Interestingly, τ0 seems to depend only on the Semenoff mass and the Haldane flux. A similar dynamics for the edge current is also expected in other systems with topological phases.

A survey of the influencing factors and models for resident's household waste management behavior

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

The problem of household solid waste has been concerned and researched on by municipalities and researchers.At present, household solid waste has been changed to management problem from technical one. From the point view of management, the research on household solid waste is to study the factors which influence resident's behavior of managtng their waste. Based on the literature review, firstly, this paper summarizes those factors which have already been identified to have impact on resident's behavior of managing their waste. They are social-demographic variables,knowledge, environmental values, psychological factors, publicity and system design. Secondly, three typical models of the relationship between factors and behavior, which are factors determining task performance in waste management,conceptualization of waste management behavior and the theoretical model of repeated behavior on household waste management, are analyzed and the deficiencies of these models are also analyzed. Finally, according to the current situation in household waste management and the culture and resident's habits in China, this paper puts forward a research focus and suggestions about resident 's behavior of household solid waste management.

Statistical modelling of discharge behavior of atmospheric pressure dielectric barrier discharge

Energy Technology Data Exchange (ETDEWEB)

Tay, W. H.; Kausik, S. S.; Wong, C. S., E-mail: cswong@um.edu.my; Yap, S. L.; Muniandy, S. V. [Plasma Technology Research Centre, Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2014-11-15

In this work, stochastic behavior of atmospheric pressure dielectric barrier discharge (DBD) has been investigated. The experiment is performed in a DBD reactor consisting of a pair of stainless steel parallel plate electrodes powered by a 50 Hz ac high voltage source. Current pulse amplitude distributions for different space gaps and the time separation between consecutive current pulses are studied. A probability distribution function is proposed to predict the experimental distribution function for the current pulse amplitudes and the occurrence of the transition regime of the pulse distribution. Breakdown voltage at different positions on the dielectric surface is suggested to be stochastic in nature. The simulated results based on the proposed distribution function agreed well with the experimental results and able to predict the regime of transition voltage. This model would be useful for the understanding of stochastic behaviors of DBD and the design of DBD device for effective operation and applications.

Conceptual Model of Iodine Behavior in the Subsurface at the Hanford Site

Energy Technology Data Exchange (ETDEWEB)

Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lee, Brady D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Christian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Last, George V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lee, Michelle H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kaplan, Daniel I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-09-01

The fate and transport of 129I in the environment and potential remediation technologies are currently being studied as part of environmental remediation activities at the Hanford Site. A conceptual model describing the nature and extent of subsurface contamination, factors that control plume behavior, and factors relevant to potential remediation processes is needed to support environmental remedy decisions. Because 129I is an uncommon contaminant, relevant remediation experience and scientific literature are limited. Thus, the conceptual model also needs to both describe known contaminant and biogeochemical process information and to identify aspects about which additional information needed to effectively support remedy decisions. this document summarizes the conceptual model of iodine behavior relevant to iodine in the subsurface environment at the Hanford site.

Can disordered mobile phone use be considered a behavioral addiction? An update on current evidence and a comprehensive model for future research

OpenAIRE

Billieux, J; Maurage, P; Lopez-Fernandez, O; Kuss, DJ; Griffiths, MD

2015-01-01

Despite the many positive outcomes, excessive mobile phone use is now often associated with potentially harmful and/or disturbing behaviors (e.g., symptoms of deregulated use, negative impact on various aspects of daily life such as relationship problems, and work intrusion). Problematic mobile phone use (PMPU) has generally been considered as a behavioral addiction that shares many features with more established drug addictions. In light of the most recent data, the current paper reviews the...

Behaviors of impurity in ITER and DEMOs using BALDUR integrated predictive modeling code

International Nuclear Information System (INIS)

Onjun, Thawatchai; Buangam, Wannapa; Wisitsorasak, Apiwat

2015-01-01

The behaviors of impurity are investigated using self-consistent modeling of 1.5D BALDUR integrated predictive modeling code, in which theory-based models are used for both core and edge region. In these simulations, a combination of NCLASS neoclassical transport and Multi-mode (MMM95) anomalous transport model is used to compute a core transport. The boundary is taken to be at the top of the pedestal, where the pedestal values are described using a theory-based pedestal model. This pedestal temperature model is based on a combination of magnetic and flow shear stabilization pedestal width scaling and an infinite-n ballooning pressure gradient model. The time evolution of plasma current, temperature and density profiles is carried out for ITER and DEMOs plasmas. As a result, the impurity behaviors such as impurity accumulation and impurity transport can be investigated. (author)

Modeling OPEC behavior: theories of risk aversion for oil producer decisions

International Nuclear Information System (INIS)

Reynolds, D.B.

1999-01-01

Theories of OPEC such as price leadership, cartel, or game theoretic models suggest an incentive for OPEC members to expand their production capacity well above current levels in order to maximize revenues. Yet individual OPEC members consistently explore for and develop oil fields at a level well below their potential. The cause of low oil exploration and development efforts among OPEC members, and even some non-OPEC members, may have to do with risk aversion. This paper describes an alternative theory for OPEC behavior based on risk aversion using a two piece non-Neumann-Morgenstern utility function similar to Fishburn and Koehenberger (1979, Decision Science 10, 503-518), and Friedman and Savage (1948, Journal of political Economy 56). The model shows possible low oil production behavior. (author)

Current induced torques and interfacial spin-orbit coupling: Semiclassical modeling

KAUST Repository

Haney, Paul M.

2013-05-07

In bilayer nanowires consisting of a ferromagnetic layer and a nonmagnetic layer with strong spin-orbit coupling, currents create torques on the magnetization beyond those found in simple ferromagnetic nanowires. The resulting magnetic dynamics appear to require torques that can be separated into two terms, dampinglike and fieldlike. The dampinglike torque is typically derived from models describing the bulk spin Hall effect and the spin transfer torque, and the fieldlike torque is typically derived from a Rashba model describing interfacial spin-orbit coupling. We derive a model based on the Boltzmann equation that unifies these approaches. We also consider an approximation to the Boltzmann equation, the drift-diffusion model, that qualitatively reproduces the behavior, but quantitatively differs in some regimes. We show that the Boltzmann equation with physically reasonable parameters can match the torques for any particular sample, but in some cases, it fails to describe the experimentally observed thickness dependencies.

Transcranial direct current stimulation (tDCS) reverts behavioral alterations and brainstem BDNF level increase induced by neuropathic pain model: Long-lasting effect.

Science.gov (United States)

Filho, Paulo Ricardo Marques; Vercelino, Rafael; Cioato, Stefania Giotti; Medeiros, Liciane Fernandes; de Oliveira, Carla; Scarabelot, Vanessa Leal; Souza, Andressa; Rozisky, Joanna Ripoll; Quevedo, Alexandre da Silva; Adachi, Lauren Naomi Spezia; Sanches, Paulo Roberto S; Fregni, Felipe; Caumo, Wolnei; Torres, Iraci L S

2016-01-04

Neuropathic pain (NP) is a chronic pain modality that usually results of damage in the somatosensory system. NP often shows insufficient response to classic analgesics and remains a challenge to medical treatment. The transcranial direct current stimulation (tDCS) is a non-invasive technique, which induces neuroplastic changes in central nervous system of animals and humans. The brain derived neurotrophic factor plays an important role in synaptic plasticity process. Behavior changes such as decreased locomotor and exploratory activities and anxiety disorders are common comorbidities associated with NP. Evaluate the effect of tDCS treatment on locomotor and exploratory activities, and anxiety-like behavior, and peripheral and central BDNF levels in rats submitted to neuropathic pain model. Rats were randomly divided: Ss, SsS, SsT, NP, NpS, and NpT. The neuropathic pain model was induced by partial sciatic nerve compression at 14 days after surgery; the tDCS treatment was initiated. The animals of treated groups were subjected to a 20 minute session of tDCS, for eight days. The Open Field and Elevated Pluz Maze tests were applied 24 h (phase I) and 7 days (phase II) after the end of tDCS treatment. The serum, spinal cord, brainstem and cerebral cortex BDNF levels were determined 48 h (phase I) and 8 days (phase II) after tDCS treatment by ELISA. The chronic constriction injury (CCI) induces decrease in locomotor and exploratory activities, increases in the behavior-like anxiety, and increases in the brainstem BDNF levels, the last, in phase II (one-way ANOVA/SNK, PtDCS treatment already reverted all these effects induced by CCI (one-way ANOVA/SNK, PtDCS treatment decreased serum and cerebral cortex BDNF levels and it increased these levels in the spinal cord in phase II (one-way ANOVA/SNK, PtDCS reverts behavioral alterations associated to neuropathic pain, indicating possible analgesic and anxiolytic tDCS effects. tDCS treatment induces changes in the BDNF levels

Modeling pedestrian shopping behavior using principles of bounded rationality: model comparison and validation

Science.gov (United States)

Zhu, Wei; Timmermans, Harry

2011-06-01

Models of geographical choice behavior have been dominantly based on rational choice models, which assume that decision makers are utility-maximizers. Rational choice models may be less appropriate as behavioral models when modeling decisions in complex environments in which decision makers may simplify the decision problem using heuristics. Pedestrian behavior in shopping streets is an example. We therefore propose a modeling framework for pedestrian shopping behavior incorporating principles of bounded rationality. We extend three classical heuristic rules (conjunctive, disjunctive and lexicographic rule) by introducing threshold heterogeneity. The proposed models are implemented using data on pedestrian behavior in Wang Fujing Street, the city center of Beijing, China. The models are estimated and compared with multinomial logit models and mixed logit models. Results show that the heuristic models are the best for all the decisions that are modeled. Validation tests are carried out through multi-agent simulation by comparing simulated spatio-temporal agent behavior with the observed pedestrian behavior. The predictions of heuristic models are slightly better than those of the multinomial logit models.

Using BPMN to model Internet of Things behavior within business process

OpenAIRE

Dulce Domingos; Francisco Martins

2017-01-01

Whereas, traditionally, business processes use the Internet of Things (IoTs) as a distributed source of information, the increase of computational capabilities of IoT devices provides them with the means to also execute parts of the business logic, reducing the amount of exchanged data and central processing. Current approaches based on Business Process Model and Notation (BPMN) already support modelers to define both business processes and IoT devices behavior at the same level of abstractio...

Using BPMN to model Internet of Things behavior within business process

Directory of Open Access Journals (Sweden)

Dulce Domingos

2017-01-01

Full Text Available Whereas, traditionally, business processes use the Internet of Things (IoTs as a distributed source of information, the increase of computational capabilities of IoT devices provides them with the means to also execute parts of the business logic, reducing the amount of exchanged data and central processing. Current approaches based on Business Process Model and Notation (BPMN already support modelers to define both business processes and IoT devices behavior at the same level of abstraction. However, they are not restricted to standard BPMN elements and they generate IoT device specific low-level code. The work we present in this paper exclusivelly uses standard BPMN to define central as well as IoT behavior of business processes. In addition, the BPMN that defines the IoT behavior is translated to a neutral-platform programming code. The deployment and execution environments use Web services to support the communication between the process execution engine and IoT devices.

Analysis of Health Behavior Theories for Clustering of Health Behaviors.

Science.gov (United States)

Choi, Seung Hee; Duffy, Sonia A

The objective of this article was to review the utility of established behavior theories, including the Health Belief Model, Theory of Reasoned Action, Theory of Planned Behavior, Transtheoretical Model, and Health Promotion Model, for addressing multiple health behaviors among people who smoke. It is critical to design future interventions for multiple health behavior changes tailored to individuals who currently smoke, yet it has not been addressed. Five health behavior theories/models were analyzed and critically evaluated. A review of the literature included a search of PubMed and Google Scholar from 2010 to 2016. Two hundred sixty-seven articles (252 studies from the initial search and 15 studies from the references of initially identified studies) were included in the analysis. Most of the health behavior theories/models emphasize psychological and cognitive constructs that can be applied only to one specific behavior at a time, thus making them not suitable to address multiple health behaviors. However, the Health Promotion Model incorporates "related behavior factors" that can explain multiple health behaviors among persons who smoke. Future multiple behavior interventions guided by the Health Promotion Model are necessary to show the utility and applicability of the model to address multiple health behaviors.

Modeling a Consistent Behavior of PLC-Sensors

Directory of Open Access Journals (Sweden)

E. V. Kuzmin

2014-01-01

Full Text Available The article extends the cycle of papers dedicated to programming and verificatoin of PLC-programs by LTL-specification. This approach provides the availability of correctness analysis of PLC-programs by the model checking method.The model checking method needs to construct a finite model of a PLC program. For successful verification of required properties it is important to take into consideration that not all combinations of input signals from the sensors can occur while PLC works with a control object. This fact requires more advertence to the construction of the PLC-program model.In this paper we propose to describe a consistent behavior of sensors by three groups of LTL-formulas. They will affect the program model, approximating it to the actual behavior of the PLC program. The idea of LTL-requirements is shown by an example.A PLC program is a description of reactions on input signals from sensors, switches and buttons. In constructing a PLC-program model, the approach to modeling a consistent behavior of PLC sensors allows to focus on modeling precisely these reactions without an extension of the program model by additional structures for realization of a realistic behavior of sensors. The consistent behavior of sensors is taken into account only at the stage of checking a conformity of the programming model to required properties, i. e. a property satisfaction proof for the constructed model occurs with the condition that the model contains only such executions of the program that comply with the consistent behavior of sensors.

Current leakage for low altitude satellites: modeling applications

International Nuclear Information System (INIS)

Konradi, A.; Mccoy, J.E.; Garriott, O.K.

1979-01-01

To simulate the behavior of a high voltage solar cell array in the ionospheric plasma environment, the large (90 ft x 55 ft diameter) vacuum chamber was used to measure the high-voltage plasma interactions of a 3 ft x 30 ft conductive panel. The chamber was filled with nitrogen and argon plasma at electron densities of up to 1,000,000 per cu cm. Measurements of current flow to the plasma were made in three configurations: (a) with one end of the panel grounded, (b) with the whole panel floating while a high bias was applied between the ends of the panel, and (c) with the whole panel at high negative voltage with respect to the chamber walls. The results indicate that a simple model with a constant panel conductivity and plasma resistance can adequately describe the voltage distribution along the panel and the plasma current flow. As expected, when a high potential difference is applied to the panel ends more than 95% of the panel floats negative with respect to the plasma

Generalized space-charge limited current and virtual cathode behaviors in one-dimensional drift space

International Nuclear Information System (INIS)

Yang, Zhanfeng; Liu, Guozhi; Shao, Hao; Chen, Changhua; Sun, Jun

2013-01-01

This paper reports the space-charge limited current (SLC) and virtual cathode behaviors in one-dimensional grounded drift space. A simple general analytical solution and an approximate solution for the planar diode are given. Through a semi-analytical method, a general solution for SLC in one-dimensional drift space is obtained. The behaviors of virtual cathode in the drift space, including dominant frequency, electron transit time, position, and transmitted current, are yielded analytically. The relationship between the frequency of the virtual cathode oscillation and the injected current presented may explain previously reported numerical works. Results are significant in facilitating estimations and further analytical studies

Current status of the FASTGRASS/PARAGRASS models for fission product release from LWR fuel during normal and accident conditions

International Nuclear Information System (INIS)

Rest, J.; Zawadski, S.A.; Piasecka, M.

1983-10-01

The theoretical FASTGRASS model for the prediction of the behavior of the gaseous and volatile fission products in nuclear fuels under normal and transient conditions has undergone substantial improvements. The major improvements have been in the atomistic and bubble diffusive flow models, in the models for the behavior of gas bubbles on grain surfaces, and in the models for the behavior of the volatile fission products iodine and cesium. The thoery has received extensive verification over a wide range of fuel operating conditions, and can be regarded as a state-of-the-art model based on our current level of understanding of fission product behavior. PARAGRASS is an extremely efficient, mechanistic computer code with the capability of modeling steady-state and transient fission-product behavior. The models in PARAGRASS are based on the more detailed ones in FASTGRASS. PARAGRASS updates for the FRAPCON (PNL), FRAP-T (INEL), and SCDAP (INEL) codes have recently been completed and implemented. Results from an extensive FASTGRASS verification are presented and discussed for steady-state and transient conditions. In addition, FASTGRASS predictions for fission product release rate constants are compared with those in NUREG-0772. 21 references, 13 figures

Gas Turbine Engine Behavioral Modeling

OpenAIRE

Meyer, Richard T; DeCarlo, Raymond A.; Pekarek, Steve; Doktorcik, Chris

2014-01-01

This paper develops and validates a power flow behavioral model of a gas tur- bine engine with a gas generator and free power turbine. “Simple” mathematical expressions to describe the engine’s power flow are derived from an understand- ing of basic thermodynamic and mechanical interactions taking place within the engine. The engine behavioral model presented is suitable for developing a supervisory level controller of an electrical power system that contains the en- gine connected to a gener...

The eHealth Behavior Management Model: a stage-based approach to behavior change and management.

Science.gov (United States)

Bensley, Robert J; Mercer, Nelda; Brusk, John J; Underhile, Ric; Rivas, Jason; Anderson, Judith; Kelleher, Deanne; Lupella, Melissa; de Jager, André C

2004-10-01

Although the Internet has become an important avenue for disseminating health information, theory-driven strategies for aiding individuals in changing or managing health behaviors are lacking. The eHealth Behavior Management Model combines the Transtheoretical Model, the behavioral intent aspect of the Theory of Planned Behavior, and persuasive communication to assist individuals in negotiating the Web toward stage-specific information. It is here - at the point of stage-specific information - that behavioral intent in moving toward more active stages of change occurs. The eHealth Behavior Management Model is applied in three demonstration projects that focus on behavior management issues: parent-child nutrition education among participants in the U.S. Department of Agriculture Special Supplemental Nutrition Program for Women, Infants and Children; asthma management among university staff and students; and human immunodeficiency virus prevention among South African women. Preliminary results have found the eHealth Behavior Management Model to be promising as a model for Internet-based behavior change programming. Further application and evaluation among other behavior and disease management issues are needed.

A Meta-Analysis of Video-Modeling Based Interventions for Reduction of Challenging Behaviors for Students with EBD

Science.gov (United States)

Losinski, Mickey; Wiseman, Nicole; White, Sherry A.; Balluch, Felicity

2016-01-01

The current study examined the use of video modeling (VM)-based interventions to reduce the challenging behaviors of students with emotional or behavioral disorders. Each study was evaluated using Council for Exceptional Children's (CEC's) quality indicators for evidence-based practices. In addition, study effects were calculated along the three…

Antecedents of employee electricity saving behavior in organizations: An empirical study based on norm activation model

International Nuclear Information System (INIS)

Zhang, Yixiang; Wang, Zhaohua; Zhou, Guanghui

2013-01-01

China is one of the major energy-consuming countries, and is under great pressure to promote energy saving and reduce domestic energy consumption. Employees constitute an important target group for energy saving. However, only a few research efforts have been paid to study what drives employee energy saving behavior in organizations. To fill this gap, drawing on norm activation model (NAM), we built a research model to study antecedents of employee electricity saving behavior in organizations. The model was empirically tested using survey data collected from office workers in Beijing, China. Results show that personal norm positively influences employee electricity saving behavior. Organizational electricity saving climate negatively moderates the effect of personal norm on electricity saving behavior. Awareness of consequences, ascription of responsibility, and organizational electricity saving climate positively influence personal norm. Furthermore, awareness of consequences positively influences ascription of responsibility. This paper contributes to the energy saving behavior literature by building a theoretical model of employee electricity saving behavior which is understudied in the current literature. Based on the empirical results, implications on how to promote employee electricity saving are discussed. - Highlights: • We studied employee electricity saving behavior based on norm activation model. • The model was tested using survey data collected from office workers in China. • Personal norm positively influences employee′s electricity saving behavior. • Electricity saving climate negatively moderates personal norm′s effect. • This research enhances our understanding of employee electricity saving behavior

An evolutionary behavioral model for decision making

OpenAIRE

Romero Lopez, Dr Oscar Javier

2011-01-01

For autonomous agents the problem of deciding what to do next becomes increasingly complex when acting in unpredictable and dynamic environments pursuing multiple and possibly conflicting goals. One of the most relevant behavior-based model that tries to deal with this problem is the one proposed by Maes, the Bbehavior Network model. This model proposes a set of behaviors as purposive perception-action units which are linked in a nonhierarchical network, and whose behavior selection process i...

Pediatric multiple sclerosis: current perspectives on health behaviors

Directory of Open Access Journals (Sweden)

Sikes EM

2018-03-01

. Discussion: Participation in health behaviors, particularly physical activity, diet, and sleep, may have benefits for POMS. Nevertheless, there are currently no interventions targeting promotion of these behaviors and examining the benefits of managing the primary and secondary manifestations of POMS. Keywords: POMS, health promotion, physical activity, diet, sleep

Sociocultural Behavior Influence Modelling & Assessment: Current Work and Research Frontiers.

Energy Technology Data Exchange (ETDEWEB)

Bernard, Michael Lewis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2018-01-01

A common problem associated with the effort to better assess potential behaviors of various individuals within different countries is the shear difficulty in comprehending the dynamic nature of populations, particularly over time and considering feedback effects. This paper discusses a theory-based analytical capability designed to enable analysts to better assess the influence of events on individuals interacting within a country or region. These events can include changes in policy, man-made or natural disasters, migration, war, or other changes in environmental/economic conditions. In addition, this paper describes potential extensions of this type of research to enable more timely and accurate assessments.

Contact behavior modelling and its size effect on proton exchange membrane fuel cell

Science.gov (United States)

Qiu, Diankai; Peng, Linfa; Yi, Peiyun; Lai, Xinmin; Janßen, Holger; Lehnert, Werner

2017-10-01

Contact behavior between the gas diffusion layer (GDL) and bipolar plate (BPP) is of significant importance for proton exchange membrane fuel cells. Most current studies on contact behavior utilize experiments and finite element modelling and focus on fuel cells with graphite BPPs, which lead to high costs and huge computational requirements. The objective of this work is to build a more effective analytical method for contact behavior in fuel cells and investigate the size effect resulting from configuration alteration of channel and rib (channel/rib). Firstly, a mathematical description of channel/rib geometry is outlined in accordance with the fabrication of metallic BPP. Based on the interface deformation characteristic and Winkler surface model, contact pressure between BPP and GDL is then calculated to predict contact resistance and GDL porosity as evaluative parameters of contact behavior. Then, experiments on BPP fabrication and contact resistance measurement are conducted to validate the model. The measured results demonstrate an obvious dependence on channel/rib size. Feasibility of the model used in graphite fuel cells is also discussed. Finally, size factor is proposed for evaluating the rule of size effect. Significant increase occurs in contact resistance and porosity for higher size factor, in which channel/rib width decrease.

Behavior model for performance assessment

International Nuclear Information System (INIS)

Brown-VanHoozer, S. A.

1999-01-01

Every individual channels information differently based on their preference of the sensory modality or representational system (visual auditory or kinesthetic) we tend to favor most (our primary representational system (PRS)). Therefore, some of us access and store our information primarily visually first, some auditorily, and others kinesthetically (through feel and touch); which in turn establishes our information processing patterns and strategies and external to internal (and subsequently vice versa) experiential language representation. Because of the different ways we channel our information, each of us will respond differently to a task--the way we gather and process the external information (input), our response time (process), and the outcome (behavior). Traditional human models of decision making and response time focus on perception, cognitive and motor systems stimulated and influenced by the three sensory modalities, visual, auditory and kinesthetic. For us, these are the building blocks to knowing how someone is thinking. Being aware of what is taking place and how to ask questions is essential in assessing performance toward reducing human errors. Existing models give predications based on time values or response times for a particular event, and may be summed and averaged for a generalization of behavior(s). However, by our not establishing a basic understanding of the foundation of how the behavior was predicated through a decision making strategy process, predicative models are overall inefficient in their analysis of the means by which behavior was generated. What is seen is the end result

Behavior model for performance assessment.

Energy Technology Data Exchange (ETDEWEB)

Borwn-VanHoozer, S. A.

1999-07-23

Every individual channels information differently based on their preference of the sensory modality or representational system (visual auditory or kinesthetic) we tend to favor most (our primary representational system (PRS)). Therefore, some of us access and store our information primarily visually first, some auditorily, and others kinesthetically (through feel and touch); which in turn establishes our information processing patterns and strategies and external to internal (and subsequently vice versa) experiential language representation. Because of the different ways we channel our information, each of us will respond differently to a task--the way we gather and process the external information (input), our response time (process), and the outcome (behavior). Traditional human models of decision making and response time focus on perception, cognitive and motor systems stimulated and influenced by the three sensory modalities, visual, auditory and kinesthetic. For us, these are the building blocks to knowing how someone is thinking. Being aware of what is taking place and how to ask questions is essential in assessing performance toward reducing human errors. Existing models give predications based on time values or response times for a particular event, and may be summed and averaged for a generalization of behavior(s). However, by our not establishing a basic understanding of the foundation of how the behavior was predicated through a decision making strategy process, predicative models are overall inefficient in their analysis of the means by which behavior was generated. What is seen is the end result.

Human Behavior Based Exploratory Model for Successful Implementation of Lean Enterprise in Industry

Science.gov (United States)

Sawhney, Rupy; Chason, Stewart

2005-01-01

Currently available Lean tools such as Lean Assessments, Value Stream Mapping, and Process Flow Charting focus on system requirements and overlook human behavior. A need is felt for a tool that allows one to baseline personnel, determine personnel requirements and align system requirements with personnel requirements. Our exploratory model--The…

Towards a characterization of behavior-disease models.

Directory of Open Access Journals (Sweden)

Nicola Perra

Full Text Available The last decade saw the advent of increasingly realistic epidemic models that leverage on the availability of highly detailed census and human mobility data. Data-driven models aim at a granularity down to the level of households or single individuals. However, relatively little systematic work has been done to provide coupled behavior-disease models able to close the feedback loop between behavioral changes triggered in the population by an individual's perception of the disease spread and the actual disease spread itself. While models lacking this coupling can be extremely successful in mild epidemics, they obviously will be of limited use in situations where social disruption or behavioral alterations are induced in the population by knowledge of the disease. Here we propose a characterization of a set of prototypical mechanisms for self-initiated social distancing induced by local and non-local prevalence-based information available to individuals in the population. We characterize the effects of these mechanisms in the framework of a compartmental scheme that enlarges the basic SIR model by considering separate behavioral classes within the population. The transition of individuals in/out of behavioral classes is coupled with the spreading of the disease and provides a rich phase space with multiple epidemic peaks and tipping points. The class of models presented here can be used in the case of data-driven computational approaches to analyze scenarios of social adaptation and behavioral change.

Students’ mental model in electric current

Science.gov (United States)

Pramesti, Y. S.; Setyowidodo, I.

2018-05-01

Electricity is one of essential topic in learning physics. This topic was studied in elementary until university level. Although electricity was related to our daily activities, but it doesn’t ensure that students have the correct concept. The aim of this research was to investigate and then categorized the students’ mental model. Subject consisted of 59 students of mechanical engineering that studied Physics for Engineering. This study was used a qualitative approach that used in this research is phenomenology. Data were analyzed qualitatively by using pre-test, post-test, and investigation for discovering further information. Three models were reported, showing a pattern which related to individual way of thinking about electric current. The mental model that was discovered in this research are: 1) electric current as a flow; 2) electric current as a source of energy, 3) electric current as a moving charge.

Modeling of strain effects on the device behaviors of ferroelectric memory field-effect transistors

International Nuclear Information System (INIS)

Yang, Feng; Hu, Guangda; Wu, Weibing; Yang, Changhong; Wu, Haitao; Tang, Minghua

2013-01-01

The influence of strains on the channel current–gate voltage behaviors and memory windows of ferroelectric memory field-effect transistors (FeMFETs) were studied using an improved model based on the Landau–Devonshire theory. ‘Channel potential–gate voltage’ ferroelectric polarization and silicon surface potential diagrams were constructed for strained single-domain BaTiO 3 FeMFETs. The compressive strains can increase (or decrease) the amplitude of transistor currents and enlarge memory windows. However, tensile strains only decrease the maximum value of transistor currents and compress memory windows. Mismatch strains were found to have a significant influence on the electrical behaviors of the devices, therefore, they must be considered in FeMFET device designing. (fast track communication)

Car-following Behavior Model Learning Using Timed Automata

NARCIS (Netherlands)

Zhang, Yihuan; Lin, Q.; Wang, Jun; Verwer, S.E.; Dochain, D.; Henrion, D.; Peaucelle, D.

Learning driving behavior is fundamental for autonomous vehicles to “understand” traffic situations. This paper proposes a novel method for learning a behavioral model of car-following using automata learning algorithms. The model is interpretable for car-following behavior analysis. Frequent common

A neural population model incorporating dopaminergic neurotransmission during complex voluntary behaviors.

Directory of Open Access Journals (Sweden)

Stefan Fürtinger

2014-11-01

Full Text Available Assessing brain activity during complex voluntary motor behaviors that require the recruitment of multiple neural sites is a field of active research. Our current knowledge is primarily based on human brain imaging studies that have clear limitations in terms of temporal and spatial resolution. We developed a physiologically informed non-linear multi-compartment stochastic neural model to simulate functional brain activity coupled with neurotransmitter release during complex voluntary behavior, such as speech production. Due to its state-dependent modulation of neural firing, dopaminergic neurotransmission plays a key role in the organization of functional brain circuits controlling speech and language and thus has been incorporated in our neural population model. A rigorous mathematical proof establishing existence and uniqueness of solutions to the proposed model as well as a computationally efficient strategy to numerically approximate these solutions are presented. Simulated brain activity during the resting state and sentence production was analyzed using functional network connectivity, and graph theoretical techniques were employed to highlight differences between the two conditions. We demonstrate that our model successfully reproduces characteristic changes seen in empirical data between the resting state and speech production, and dopaminergic neurotransmission evokes pronounced changes in modeled functional connectivity by acting on the underlying biological stochastic neural model. Specifically, model and data networks in both speech and rest conditions share task-specific network features: both the simulated and empirical functional connectivity networks show an increase in nodal influence and segregation in speech over the resting state. These commonalities confirm that dopamine is a key neuromodulator of the functional connectome of speech control. Based on reproducible characteristic aspects of empirical data, we suggest a number

Behavioral modelling and predistortion of wideband wireless transmitters

CERN Document Server

Ghannouchi, Fadhel M; Helaoui, Mohamed

2015-01-01

Covers theoretical and practical aspects related to the behavioral modelling and predistortion of wireless transmitters and power amplifiers. It includes simulation software that enables the users to apply the theory presented in the book. In the first section, the reader is given the general background of nonlinear dynamic systems along with their behavioral modelling from all its aspects. In the second part, a comprehensive compilation of behavioral models formulations and structures is provided including memory polynomial based models, box oriented models such as Hammerstein-based and Wiene

Cognitive Modeling of Social Behaviors

Science.gov (United States)

Clancey, William J.; Sierhuis, Maarten; Damer. Bruce; Brodsky, Boris

2004-01-01

The driving theme of cognitive modeling for many decades has been that knowledge affects how and which goals are accomplished by an intelligent being (Newell 1991). But when one examines groups of people living and working together, one is forced to recognize that whose knowledge is called into play, at a particular time and location, directly affects what the group accomplishes. Indeed, constraints on participation, including roles, procedures, and norms, affect whether an individual is able to act at all (Lave & Wenger 1991; Jordan 1992; Scribner & Sachs 1991). To understand both individual cognition and collective activity, perhaps the greatest opportunity today is to integrate the cognitive modeling approach (which stresses how beliefs are formed and drive behavior) with social studies (which stress how relationships and informal practices drive behavior). The crucial insight is that norms are conceptualized in the individual &nd as ways of carrying out activities (Clancey 1997a, 2002b). This requires for the psychologist a shift from only modeling goals and tasks - why people do what they do - to modeling behavioral patterns-what people do-as they are engaged in purposeful activities. Instead of a model that exclusively deduces actions from goals, behaviors are also, if not primarily, driven by broader patterns of chronological and located activities (akin to scripts). This analysis is particular inspired by activity theory (Leont ev 1979). While acknowledging that knowledge (relating goals and operations) is fundamental for intelligent behavior, activity theory claims that a broader driver is the person s motives and conceptualization of activities. Such understanding of human interaction is normative (i.e., viewed with respect to social standards), affecting how knowledge is called into play and applied in practice. Put another way, how problems are discovered and framed, what methods are chosen, and indeed who even cares or has the authority to act, are all

Storm-time ring current: model-dependent results

Directory of Open Access Journals (Sweden)

N. Yu. Ganushkina

2012-01-01

Full Text Available The main point of the paper is to investigate how much the modeled ring current depends on the representations of magnetic and electric fields and boundary conditions used in simulations. Two storm events, one moderate (SymH minimum of −120 nT on 6–7 November 1997 and one intense (SymH minimum of −230 nT on 21–22 October 1999, are modeled. A rather simple ring current model is employed, namely, the Inner Magnetosphere Particle Transport and Acceleration model (IMPTAM, in order to make the results most evident. Four different magnetic field and two electric field representations and four boundary conditions are used. We find that different combinations of the magnetic and electric field configurations and boundary conditions result in very different modeled ring current, and, therefore, the physical conclusions based on simulation results can differ significantly. A time-dependent boundary outside of 6.6 RE gives a possibility to take into account the particles in the transition region (between dipole and stretched field lines forming partial ring current and near-Earth tail current in that region. Calculating the model SymH* by Biot-Savart's law instead of the widely used Dessler-Parker-Sckopke (DPS relation gives larger and more realistic values, since the currents are calculated in the regions with nondipolar magnetic field. Therefore, the boundary location and the method of SymH* calculation are of key importance for ring current data-model comparisons to be correctly interpreted.

Parents' attachment histories and children's externalizing and internalizing behaviors: exploring family systems models of linkage.

Science.gov (United States)

Cowan, P A; Cowan, C P; Cohn, D A; Pearson, J L

1996-02-01

Twenty-seven mothers and 27 fathers were given the Adult Attachment Interview (M. Main & R. Goldwyn, in press) when their children were 3.5 years old. Continuous ratings of narrative coherence, probable experience quality (parents perceived as loving), and state of mind (current anger at parents) were entered as latent variables in partial least squares structural equation models that included observational measures of marital quality and parenting style. Models that include fathers' attachment histories predicted more variance in kindergarten teachers' descriptions of children's externalizing behavior, whereas models that include mothers' attachment histories predicted more variance in children's internalizing behavior. Marital data added predictive power to the equations. Discussion is focused on the importance of integrating attachment and family systems approaches, and of parents' gender and marital quality, in understanding specific links between parents' attachment histories and their young children's externalizing and internalizing behaviors.

Aids to determining fuel models for estimating fire behavior

Science.gov (United States)

Hal E. Anderson

1982-01-01

Presents photographs of wildland vegetation appropriate for the 13 fuel models used in mathematical models of fire behavior. Fuel model descriptions include fire behavior associated with each fuel and its physical characteristics. A similarity chart cross-references the 13 fire behavior fuel models to the 20 fuel models used in the National Fire Danger Rating System....

Social Fingerprinting: detection of spambot groups through DNA-inspired behavioral modeling

DEFF Research Database (Denmark)

Cresci, Stefano; Di Pietro, Roberto; Petrocchi, Marinella

2017-01-01

Spambot detection in online social networks is a long-lasting challenge involving the study and design of detection techniques capable of efficiently identifying ever-evolving spammers. Recently, a new wave of social spambots has emerged, with advanced human-like characteristics that allow them...... to go undetected even by current state-of-the-art algorithms. In this paper, we show that efficient spambots detection can be achieved via an in-depth analysis of their collective behaviors exploiting the digital DNA technique for modeling the behaviors of social network users. Inspired by its...... biological counterpart, in the digital DNA representation the behavioral lifetime of a digital account is encoded in a sequence of characters. Then, we define a similarity measure for such digital DNA sequences. We build upon digital DNA and the similarity between groups of users to characterize both genuine...

Blood flow behavior in microchannels: past, current and future trends

OpenAIRE

Lima, R.; Ishikawa, Takuji; Imai, Yohsuke; Yamaguchi, Takami

2012-01-01

Over the years, various experimental methods have been applied in an effort to understand the blood flow behavior in microcirculation. Most of our current knowledge in microcirculation is based on macroscopic flow phenomena such as Fahraeus effect and Fahraeus-Linqvist effect. The development of optical experimental techniques has contributed to obtain possible explanations on the way the blood flows through microvessels. Although the past results have been encouraging, detailed s...

A simplified model of choice behavior under uncertainty

Directory of Open Access Journals (Sweden)

Ching-Hung Lin

2016-08-01

Full Text Available The Iowa Gambling Task (IGT has been standardized as a clinical assessment tool (Bechara, 2007. Nonetheless, numerous research groups have attempted to modify IGT models to optimize parameters for predicting the choice behavior of normal controls and patients. A decade ago, most researchers considered the expected utility (EU model (Busemeyer and Stout, 2002 to be the optimal model for predicting choice behavior under uncertainty. However, in recent years, studies have demonstrated the prospect utility (PU models (Ahn et al., 2008 to be more effective than the EU models in the IGT. Nevertheless, after some preliminary tests, we propose that Ahn et al. (2008 PU model is not optimal due to some incompatible results between our behavioral and modeling data. This study aims to modify Ahn et al. (2008 PU model to a simplified model and collected 145 subjects’ IGT performance as the benchmark data for comparison. In our simplified PU model, the best goodness-of-fit was found mostly while α approaching zero. More specifically, we retested the key parameters α, λ , and A in the PU model. Notably, the power of influence of the parameters α, λ, and A has a hierarchical order in terms of manipulating the goodness-of-fit in the PU model. Additionally, we found that the parameters λ and A may be ineffective when the parameter α is close to zero in the PU model. The present simplified model demonstrated that decision makers mostly adopted the strategy of gain-stay-loss-shift rather than foreseeing the long-term outcome. However, there still have other behavioral variables that are not well revealed under these dynamic uncertainty situations. Therefore, the optimal behavioral models may not have been found. In short, the best model for predicting choice behavior under dynamic-uncertainty situations should be further evaluated.

Modeling Architectural Patterns’ Behavior Using Architectural Primitives

NARCIS (Netherlands)

Waqas Kamal, Ahmad; Avgeriou, Paris

2008-01-01

Architectural patterns have an impact on both the structure and the behavior of a system at the architecture design level. However, it is challenging to model patterns’ behavior in a systematic way because modeling languages do not provide the appropriate abstractions and because each pattern

Organizational leadership: motives and behaviors of leaders in current organizations.

Science.gov (United States)

Martí, Margarita; Gil, Francisco; Barrasa, Angel

2009-05-01

Organizational leadership is fundamental for the working and development of current organizations. It helps members of an organization to face transcendental challenges. One of the fundamental aspects of leaders is their personal characteristics and behaviour as perceived by their co-workers. Although research has established a relationship between these components, findings have failed to come up with any congruent evidence and further to this the organizations and contexts used are from several decades ago. This article, which forms part of the international GLOBE project, analyses the relationship between motives and behaviour as perceived by co-workers in organizations, using quantitative and qualitative methods and including technological innovations. Using samples from 40 corporate directors and 84 of their co-workers, from different companies, it confirms how the main motives of leaders (power, affiliation and achievement) are related to different behavioral patterns (power to authoritarian, non-dependent and non-social-skill behaviours; affiliation to relationship and dependent behaviors, and achievement to proactive behaviors). It discusses the results with relation to traditional research and suggests practical measures and proposals for future investigations in this area.

Modeling plasma behavior in a plasma electrode Pockels cell

International Nuclear Information System (INIS)

Boley, C.D.; Rhodes, M.A.

1999-01-01

The authors present three interrelated models of plasma behavior in a plasma electrode Pockels cell (PEPC). In a PEPC, plasma discharges are formed on both sides of a thin, large-aperture electro-optic crystal (typically KDP). The plasmas act as optically transparent, highly conductive electrodes, allowing uniform application of a longitudinal field to induce birefringence in the crystal. First, they model the plasma in the thin direction, perpendicular to the crystal, via a one-dimensional fluid model. This yields the electron temperature and the density and velocity profiles in this direction as functions of the neutral pressure, the plasma channel width, and the discharge current density. Next, they model the temporal response of the crystal to the charging process, combining a circuit model with a model of the sheath which forms near the crystal boundary. This model gives the time-dependent voltage drop across the sheath as a function of electron density at the sheath entrance. Finally, they develop a two-dimensional MHD model of the planar plasma, in order to calculate the response of the plasma to magnetic fields. They show how the plasma uniformity is affected by the design of the current return, by the longitudinal field from the cathode magnetron, and by fields from other sources. This model also gives the plasma sensitivity to the boundary potential at which the top and bottom of the discharge are held. They validate these models by showing how they explain observations in three large Pockels cells built at Lawrence Livermore National Laboratory

Emotional and Behavioral Disorders in South Korea: Current Status and Issues

Science.gov (United States)

Kim, Joungmin; Kim, Kyeong-hwa

2016-01-01

In South Korea, there is no consensus on the definition of emotional and behavioral disorders (EBD). This column focuses on how the definition has affected the prevalence rates and services available for students with EBDs. Of the legal, clinical, and educational definitions, the legal definition of EBDs is currently in common use, which raises…

On track for success: an innovative behavioral science curriculum model.

Science.gov (United States)

Freedy, John R; Carek, Peter J; Dickerson, Lori M; Mallin, Robert M

2013-01-01

This article describes the behavioral science curriculum currently in place at the Trident/MUSC Family Medicine Residency Program. The Trident/MUSC Program is a 10-10-10 community-based, university-affiliated program in Charleston, South Carolina. Over the years, the Trident/MUSC residency program has graduated over 400 Family Medicine physicians. The current behavioral science curriculum consists of both required core elements (didactic lectures, clinical observation, Balint groups, and Resident Grand Rounds) as well as optional elements (longitudinal patient care experiences, elective rotations, behavioral science editorial experience, and scholars project with a behavioral science focus). All Trident/MUSC residents complete core behavioral science curriculum elements and are free to participate in none, some, or all of the optional behavioral science curriculum elements. This flexibility allows resident physicians to tailor the educational program in a manner to meet individual educational needs. The behavioral science curriculum is based upon faculty interpretation of existing "best practice" guidelines (Residency Review Committee-Family Medicine and AAFP). This article provides sufficient curriculum detail to allow the interested reader the opportunity to adapt elements of the behavioral science curriculum to other residency training programs. While this behavioral science track system is currently in an early stage of implementation, the article discusses track advantages as well as future plans to evaluate various aspects of this innovative educational approach.

Modeling Pseudo-elastic Behavior of Springback

International Nuclear Information System (INIS)

Xia, Z. Cedric

2005-01-01

One of the principal foundations of mathematical theory of conventional plasticity for rate-independent metals is that there exists a well-defined yield surface in stress space for any material point under deformation. A material point can undergo further plastic deformation if the applied stresses are beyond current yield surface which is generally referred as 'plastic loading'. On the other hand, if the applied stress state falls within or on the yield surface, the metal will deform elastically only and is said to be undergoing 'elastic unloading'. Although it has been always recognized throughout the history of development of plasticity theory that there is indeed inelastic deformation accompanying elastic unloading, which leads to metal's hysteresis behavior, its effects were thought to be negligible and were largely ignored in the mathematical treatment.Recently there have been renewed interests in the study of unloading behavior of sheet metals upon large plastic deformation and its implications on springback prediction. Springback is essentially an elastic recovery process of a formed sheet metal blank when it is released from the forming dies. Its magnitude depends on the stress states and compliances of the deformed sheet metal if no further plastic loading occurs during the relaxation process. Therefore the accurate determination of material compliances during springback and its effective incorporation into simulation software are important aspects for springback calculation. Some of the studies suggest that the unloading curve might deviate from linearity, and suggestions were made that a reduced elastic modulus be used for springback simulation.The aim of this study is NOT to take a position on the debate of whether elastic moduli are changed during sheet metal forming process. Instead we propose an approach of modeling observed psuedoelastic behavior within the context of mathematical theory of plasticity, where elastic moduli are treated to be

Application of the transtheoretical model to sedentary behaviors and its association with physical activity status.

Directory of Open Access Journals (Sweden)

Ho Han

Full Text Available The Transtheoretical Model (TTM is a successful framework for guiding behavior change programs for several health behaviors, yet its application to reduce of sedentary behavior has been neglected. In addition, no data exist regarding the association between determinants of sedentary behaviors based on the TTM and physical activity behavior. The purpose of this study was to investigate college students' stages of motivational readiness to avoid sedentary behaviors and relevant psychological determinants using newly developed TTM questionnaires and to identify the association between current physical activity and sedentary behaviors based on TTM constructs.Data were obtained from 225 college students enrolled in health education and physical education courses. Participants completed a package of questionnaires including validated TTM, physical activity and sitting time questionnaires. Participants also wore an accelerometer for seven consecutive days. MANOVAs were conducted to determine mean differences in psychological constructs across the TTM stages, and Chi-square tests and Spearman correlation were used to evaluate the associations between current physical activity and sedentary behavior.A majority of the participants were in the sedentary stages, and men and women differed in proportion of individuals in the stages (78.0% vs. 68.1%, respectively. The gender difference was also found in use of the processes of change. In general, the mean scores of the TTM constructs increased as the stages progressed. No significant associations were found between the TTM constructs for sedentary behavior and current physical activity levels (p>0.05.A high proportion of college students were in sedentary stages regardless of physical activity levels, but different distributions in men and women. Participants in earlier stages were less likely to utilize the TTM constructs to reduce sedentary behaviors than those in later stages. A lack of association between

Behavior genetics: Bees as model

International Nuclear Information System (INIS)

Nates Parra, Guiomar

2011-01-01

The honeybee Apis mellifera (Apidae) is a model widely used in behavior because of its elaborate social life requiring coordinate actions among the members of the society. Within a colony, division of labor, the performance of tasks by different individuals, follows genetically determined physiological changes that go along with aging. Modern advances in tools of molecular biology and genomics, as well as the sequentiation of A. mellifera genome, have enabled a better understanding of honeybee behavior, in particular social behavior. Numerous studies show that aspects of worker behavior are genetically determined, including defensive, hygienic, reproductive and foraging behavior. For example, genetic diversity is associated with specialization to collect water, nectar and pollen. Also, control of worker reproduction is associated with genetic differences. In this paper, I review the methods and the main results from the study of the genetic and genomic basis of some behaviors in bees.

Modeling pedestrian shopping behavior using principles of bounded rationality: model comparison and validation

NARCIS (Netherlands)

Zhu, W.; Timmermans, H.J.P.

2011-01-01

Models of geographical choice behavior have been dominantly based on rational choice models, which assume that decision makers are utility-maximizers. Rational choice models may be less appropriate as behavioral models when modeling decisions in complex environments in which decision makers may

A Conceptual Model of Leisure-Time Choice Behavior.

Science.gov (United States)

Bergier, Michel J.

1981-01-01

Methods of studying the gap between predisposition and actual behavior of consumers of spectator sports is discussed. A model is drawn from the areas of behavioral sciences, consumer behavior, and leisure research. The model is constructed around the premise that choice is primarily a function of personal, product, and environmental factors. (JN)

Unraveling the sub-processes of selective attention: insights from dynamic modeling and continuous behavior.

Science.gov (United States)

Frisch, Simon; Dshemuchadse, Maja; Görner, Max; Goschke, Thomas; Scherbaum, Stefan

2015-11-01

Selective attention biases information processing toward stimuli that are relevant for achieving our goals. However, the nature of this bias is under debate: Does it solely rely on the amplification of goal-relevant information or is there a need for additional inhibitory processes that selectively suppress currently distracting information? Here, we explored the processes underlying selective attention with a dynamic, modeling-based approach that focuses on the continuous evolution of behavior over time. We present two dynamic neural field models incorporating the diverging theoretical assumptions. Simulations with both models showed that they make similar predictions with regard to response times but differ markedly with regard to their continuous behavior. Human data observed via mouse tracking as a continuous measure of performance revealed evidence for the model solely based on amplification but no indication of persisting selective distracter inhibition.

Polymer models with optimal good-solvent behavior

Science.gov (United States)

D'Adamo, Giuseppe; Pelissetto, Andrea

2017-11-01

We consider three different continuum polymer models, which all depend on a tunable parameter r that determines the strength of the excluded-volume interactions. In the first model, chains are obtained by concatenating hard spherocylinders of height b and diameter rb (we call them thick self-avoiding chains). The other two models are generalizations of the tangent hard-sphere and of the Kremer-Grest models. We show that for a specific value r* , all models show optimal behavior: asymptotic long-chain behavior is observed for relatively short chains. For r < r* , instead, the behavior can be parametrized by using the two-parameter model, which also describes the thermal crossover close to the θ point. The bonds of the thick self-avoiding chains cannot cross each other, and therefore the model is suited for the investigation of topological properties and for dynamical studies. Such a model also provides a coarse-grained description of double-stranded DNA, so that we can use our results to discuss under which conditions DNA can be considered as a model good-solvent polymer.

Using the Integrative Model of Behavioral Prediction to Understand College Students' STI Testing Beliefs, Intentions, and Behaviors.

Science.gov (United States)

Wombacher, Kevin; Dai, Minhao; Matig, Jacob J; Harrington, Nancy Grant

2018-03-22

To identify salient behavioral determinants related to STI testing among college students by testing a model based on the integrative model of behavioral (IMBP) prediction. 265 undergraduate students from a large university in the Southeastern US. Formative and survey research to test an IMBP-based model that explores the relationships between determinants and STI testing intention and behavior. Results of path analyses supported a model in which attitudinal beliefs predicted intention and intention predicted behavior. Normative beliefs and behavioral control beliefs were not significant in the model; however, select individual normative and control beliefs were significantly correlated with intention and behavior. Attitudinal beliefs are the strongest predictor of STI testing intention and behavior. Future efforts to increase STI testing rates should identify and target salient attitudinal beliefs.

Model of Collective Fish Behavior with Hydrodynamic Interactions

Science.gov (United States)

Filella, Audrey; Nadal, François; Sire, Clément; Kanso, Eva; Eloy, Christophe

2018-05-01

Fish schooling is often modeled with self-propelled particles subject to phenomenological behavioral rules. Although fish are known to sense and exploit flow features, these models usually neglect hydrodynamics. Here, we propose a novel model that couples behavioral rules with far-field hydrodynamic interactions. We show that (1) a new "collective turning" phase emerges, (2) on average, individuals swim faster thanks to the fluid, and (3) the flow enhances behavioral noise. The results of this model suggest that hydrodynamic effects should be considered to fully understand the collective dynamics of fish.

The SEM Risk Behavior (SRB) Model: A New Conceptual Model of how Pornography Influences the Sexual Intentions and HIV Risk Behavior of MSM.

Science.gov (United States)

Wilkerson, J Michael; Iantaffi, Alex; Smolenski, Derek J; Brady, Sonya S; Horvath, Keith J; Grey, Jeremy A; Rosser, B R Simon

2012-01-01

While the effects of sexually explicit media (SEM) on heterosexuals' sexual intentions and behaviors have been studied, little is known about the consumption and possible influence of SEM among men who have sex with men (MSM). Importantly, conceptual models of how Internet-based SEM influences behavior are lacking. Seventy-nine MSM participated in online focus groups about their SEM viewing preferences and sexual behavior. Twenty-three participants reported recent exposure to a new behavior via SEM. Whether participants modified their sexual intentions and/or engaged in the new behavior depended on three factors: arousal when imagining the behavior, pleasure when attempting the behavior, and trust between sex partners. Based on MSM's experience, we advance a model of how viewing a new sexual behavior in SEM influences sexual intentions and behaviors. The model includes five paths. Three paths result in the maintenance of sexual intentions and behaviors. One path results in a modification of sexual intentions while maintaining previous sexual behaviors, and one path results in a modification of both sexual intentions and behaviors. With this model, researchers have a framework to test associations between SEM consumption and sexual intentions and behavior, and public health programs have a framework to conceptualize SEM-based HIV/STI prevention programs.

Current density and continuity in discretized models

International Nuclear Information System (INIS)

Boykin, Timothy B; Luisier, Mathieu; Klimeck, Gerhard

2010-01-01

Discrete approaches have long been used in numerical modelling of physical systems in both research and teaching. Discrete versions of the Schroedinger equation employing either one or several basis functions per mesh point are often used by senior undergraduates and beginning graduate students in computational physics projects. In studying discrete models, students can encounter conceptual difficulties with the representation of the current and its divergence because different finite-difference expressions, all of which reduce to the current density in the continuous limit, measure different physical quantities. Understanding these different discrete currents is essential and requires a careful analysis of the current operator, the divergence of the current and the continuity equation. Here we develop point forms of the current and its divergence valid for an arbitrary mesh and basis. We show that in discrete models currents exist only along lines joining atomic sites (or mesh points). Using these results, we derive a discrete analogue of the divergence theorem and demonstrate probability conservation in a purely localized-basis approach.

Modeling detour behavior of pedestrian dynamics under different conditions

Science.gov (United States)

Qu, Yunchao; Xiao, Yao; Wu, Jianjun; Tang, Tao; Gao, Ziyou

2018-02-01

Pedestrian simulation approach has been widely used to reveal the human behavior and evaluate the performance of crowd evacuation. In the existing pedestrian simulation models, the social force model is capable of predicting many collective phenomena. Detour behavior occurs in many cases, and the important behavior is a dominate factor of the crowd evacuation efficiency. However, limited attention has been attracted for analyzing and modeling the characteristics of detour behavior. In this paper, a modified social force model integrated by Voronoi diagram is proposed to calculate the detour direction and preferred velocity. Besides, with the consideration of locations and velocities of neighbor pedestrians, a Logit-based choice model is built to describe the detour direction choice. The proposed model is applied to analyze pedestrian dynamics in a corridor scenario with either unidirectional or bidirectional flow, and a building scenario in real-world. Simulation results show that the modified social force model including detour behavior could reduce the frequency of collision and deadlock, increase the average speed of the crowd, and predict more practical crowd dynamics with detour behavior. This model can also be potentially applied to understand the pedestrian dynamics and design emergent management strategies for crowd evacuations.

How does sex matter? Behavior, stress and animal models of neurobehavioral disorders.

Science.gov (United States)

Palanza, Paola; Parmigiani, Stefano

2017-05-01

Many aspects of brain functioning exhibit important sex differences that affect behavior, mental health and mental disorders. However, most translational neuroscience research related to animal models of neurobehavioral disorders are carried out in male animals only. Based on published data from our laboratory on the House mouse, we discuss the following issues: (1) sex differences in social behavior of wild-derived mice; (2) artificial selection of laboratory strains and its consequences on social and reproductive competition; (3) sex-dependent effects of common experimental procedures; (4) differential effects of developmental events: the case of endocrine disruption; (5) implications for female models of stress and neurobehavioral disorders. Altogether, this review of data outline the marked differences of male and female responses to different social challenges and evinces the current lack of a relevant female mouse model of social stress. Whilst animal modelling is an important approach towards understanding mechanisms of neurobehavioral disorders, it is evident that data obtained in males may be irrelevant for inferring psychopathology and efficacy of pharmacological treatments for females. Copyright © 2017 Elsevier Ltd. All rights reserved.

Is running away right? The behavioral activation-behavioral inhibition model of anterior asymmetry.

Science.gov (United States)

Wacker, Jan; Chavanon, Mira-Lynn; Leue, Anja; Stemmler, Gerhard

2008-04-01

The measurement of anterior electroencephalograph (EEG) asymmetries has become an important standard paradigm for the investigation of affective states and traits. Findings in this area are typically interpreted within the motivational direction model, which suggests a lateralization of approach and withdrawal motivational systems to the left and right anterior region, respectively. However, efforts to compare this widely adopted model with an alternative account-which relates the left anterior region to behavioral activation independent of the direction of behavior (approach or withdrawal) and the right anterior region to goal conflict-induced behavioral inhibition-are rare and inconclusive. Therefore, the authors measured the EEG in a sample of 93 young men during emotional imagery designed to provide a critical test between the 2 models. The results (e.g., a correlation between left anterior activation and withdrawal motivation) favor the alternative model on the basis of the concepts of behavioral activation and behavioral inhibition. In addition, the present study also supports an association of right parietal activation with physiological arousal and the conceptualization of parietal EEG asymmetry as a mediator of emotion-related physiological arousal. (Copyright) 2008 APA.

A Conceptual Model of Investor Behavior

NARCIS (Netherlands)

M. Lovric (Milan); U. Kaymak (Uzay); J. Spronk (Jaap)

2008-01-01

textabstractBased on a survey of behavioral finance literature, this paper presents a descriptive model of individual investor behavior in which investment decisions are seen as an iterative process of interactions between the investor and the investment environment. This investment process is

Models of iodine behavior in reactor containments

Energy Technology Data Exchange (ETDEWEB)

Weber, C.F.; Beahm, E.C.; Kress, T.S.

1992-10-01

Models are developed for many phenomena of interest concerning iodine behavior in reactor containments during severe accidents. Processes include speciation in both gas and liquid phases, reactions with surfaces, airborne aerosols, and other materials, and gas-liquid interface behavior. Although some models are largely empirical formulations, every effort has been made to construct mechanistic and rigorous descriptions of relevant chemical processes. All are based on actual experimental data generated at the Oak Ridge National Laboratory (ORNL) or elsewhere, and, hence, considerable data evaluation and parameter estimation are contained in this study. No application or encoding is attempted, but each model is stated in terms of rate processes, with the intention of allowing mechanistic simulation. Taken together, this collection of models represents a best estimate iodine behavior and transport in reactor accidents.

Models of iodine behavior in reactor containments

International Nuclear Information System (INIS)

Weber, C.F.; Beahm, E.C.; Kress, T.S.

1992-10-01

Models are developed for many phenomena of interest concerning iodine behavior in reactor containments during severe accidents. Processes include speciation in both gas and liquid phases, reactions with surfaces, airborne aerosols, and other materials, and gas-liquid interface behavior. Although some models are largely empirical formulations, every effort has been made to construct mechanistic and rigorous descriptions of relevant chemical processes. All are based on actual experimental data generated at the Oak Ridge National Laboratory (ORNL) or elsewhere, and, hence, considerable data evaluation and parameter estimation are contained in this study. No application or encoding is attempted, but each model is stated in terms of rate processes, with the intention of allowing mechanistic simulation. Taken together, this collection of models represents a best estimate iodine behavior and transport in reactor accidents

Understanding the Consumers’ Behavior Intention in Using Green Ecolabel Product through Pro-Environmental Planned Behavior Model in Developing and Developed Regions: Lessons Learned from Taiwan and Indonesia

Directory of Open Access Journals (Sweden)

Ilma Mufidah

2018-05-01

Full Text Available An ecolabel product is an environmentally friendly substance that can be selected to maintain environmental sustainability. Both developed and developing regions are promoting the use of green products. The current study aimed to know the behavior intention on ecolabel product usage from citizens in developing and developed regions. The extended Theory of Planned Behavior, known as Pro-Environmental Planned Behavior Model (PEPB, was used as the assessment model. Two questionnaire surveys were conducted to extract the necessary information for analyzing user’s behavior intention in two different regions. Taiwan and Indonesia were selected as case studies of developed and developing regions, respectively. Structural Equation Modeling (SEM was used to analyze the proposed model and the result reveals that the model explains 49% of behavior intention to use ecolabel product in Taiwan’s case and 72% in Indonesia’s case. The findings revealed that attitude (AT is the key factor to determine the behavioral intention (BI in both Taiwan and Indonesia. Several practical recommendations based on the finding can be considered as input for the governments and related agencies to persuade manufacturing companies to produce more ecolabel products. Increased citizens’ intention to use ecolabel products help the company to reach broader target market and provide incentives to manufacturing companies to produce more environmentally friendly products.

An integrative model of organizational safety behavior.

Science.gov (United States)

Cui, Lin; Fan, Di; Fu, Gui; Zhu, Cherrie Jiuhua

2013-06-01

This study develops an integrative model of safety management based on social cognitive theory and the total safety culture triadic framework. The purpose of the model is to reveal the causal linkages between a hazardous environment, safety climate, and individual safety behaviors. Based on primary survey data from 209 front-line workers in one of the largest state-owned coal mining corporations in China, the model is tested using structural equation modeling techniques. An employee's perception of a hazardous environment is found to have a statistically significant impact on employee safety behaviors through a psychological process mediated by the perception of management commitment to safety and individual beliefs about safety. The integrative model developed here leads to a comprehensive solution that takes into consideration the environmental, organizational and employees' psychological and behavioral aspects of safety management. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.

A psycho-behavioral perspective on modelling obsessive-compulsive disorder (OCD) in animals: The role of context

Science.gov (United States)

Wolmarans, De Wet; Stein, Dan J; Harvey, Brian H

2017-05-23

Obsessive-compulsive disorder is a heterogeneous and debilitating condition, characterized by intrusive thoughts and compulsive repetition. Animal models of OCD are important tools that have the potential to contribute significantly to our understanding of the condition. Although there is consensus that pre-clinical models are valuable in elucidating the underlying neurobiology in psychiatric disorders, the current paper attempts to prompt ideas on how interpretation of animal behavior can be expanded upon to more effectively converge with the human disorder. Successful outcomes in psychopharmacology involves rational design and synthesis of novel compounds and their testing in well-designed animal models. As part of a special journal issue on OCD, this paper will 1) review the psycho-behavioral aspects of OCD that are of importance on how the above ideas can be articulated, 2) briefly elaborate on general issues that are important for the development of animal models of OCD, with a particular focus on the role and importance of context, 3) propose why translational progress may often be less than ideal, 4) highlight some of the significant contributions afforded by animal models to advance understanding, and 5) conclude by identifying novel behavioral constructs for future investigations that may contribute to the face, predictive and construct validity of OCD animal models. We base these targets on an integrative approach to face and construct validity, and note that the issue of treatment-resistance in the clinical context should receive attention in current animal models of OCD. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Progressive current degradation and breakdown behavior in GaN LEDs under high reverse bias stress

International Nuclear Information System (INIS)

Zhao Linna; Yu Peihong; Yan Dawei; Zhou Hao; Wu Jinbo; Cui Zhiqiang; Gu Xiaofeng; Guo Zixiang; Sun Huarui

2017-01-01

The progressive current degradation and breakdown behaviors of GaN-based light emitting diodes under high reverse-bias stress are studied by combining the electrical, optical, and surface morphology characterizations. The current features a typical “soft breakdown” behavior, which is linearly correlated to an increase of the accumulative number of electroluminescence spots. The time-to-failure for each failure site approximately obeys a Weibull distribution with slopes of about 0.67 and 4.09 at the infant and wear-out periods, respectively. After breakdown, visible craters can be observed at the device surface as a result of transient electrostatic discharge. By performing focused ion beam cuts coupled with scan electron microscope, we observed a local current shunt path in the surface layer, caused by the rapid microstructure deterioration due to significant current heating effect, consistent well with the optical beam induced resistance change observations. (paper)

The Information–Motivation–Behavioral Skills Model of ART Adherence in a Deep South HIV+ Clinic Sample

Science.gov (United States)

Amico, K. Rivet; Barta, William; Konkle-Parker, Deborah J.; Fisher, Jeffrey D.; Cornman, Deborah H.; Shuper, Paul A.; Fisher, William A.

2011-01-01

High levels of adherence to antiretroviral therapy (ART) are critical to the management of HIV, yet many people living with HIV do not achieve these levels. There is a substantial body of literature regarding correlates of adherence to ART, and theory-based multivariate models of ART adherence are emerging. The current study assessed the determinants of adherence behavior postulated by the Information–Motivation–Behavioral Skills model of ART adherence in a sample of 149 HIV-positive patients in Mississippi. Structural equation modeling indicated that ART-related information correlated with personal and social motivation, and the two sub-areas of motivation were not intercorrelated. In this Deep South sample, being better informed, socially supported, and perceiving fewer negative consequences of adherence were independently related to stronger behavioral skills for taking medications, which in turn associated with self-reported adherence. The IMB model of ART adherence appeared to well characterize the complexities of adherence for this sample. PMID:17876697

The information-motivation-behavioral skills model of ART adherence in a Deep South HIV+ clinic sample.

Science.gov (United States)

Amico, K Rivet; Barta, William; Konkle-Parker, Deborah J; Fisher, Jeffrey D; Cornman, Deborah H; Shuper, Paul A; Fisher, William A

2009-02-01

High levels of adherence to antiretroviral therapy (ART) are critical to the management of HIV, yet many people living with HIV do not achieve these levels. There is a substantial body of literature regarding correlates of adherence to ART, and theory-based multivariate models of ART adherence are emerging. The current study assessed the determinants of adherence behavior postulated by the Information-Motivation-Behavioral Skills model of ART adherence in a sample of 149 HIV-positive patients in Mississippi. Structural equation modeling indicated that ART-related information correlated with personal and social motivation, and the two sub-areas of motivation were not intercorrelated. In this Deep South sample, being better informed, socially supported, and perceiving fewer negative consequences of adherence were independently related to stronger behavioral skills for taking medications, which in turn associated with self-reported adherence. The IMB model of ART adherence appeared to well characterize the complexities of adherence for this sample.

Levitation of current carrying states in the lattice model for the integer quantum Hall effect.

Science.gov (United States)

Koschny, T; Potempa, H; Schweitzer, L

2001-04-23

The disorder driven quantum Hall to insulator transition is investigated for a two-dimensional lattice model. The Hall conductivity and the localization length are calculated numerically near the transition. For uncorrelated and weakly correlated disorder potentials the current carrying states are annihilated by the negative Chern states originating from the band center. In the presence of correlated disorder potentials with correlation length larger than approximately half the lattice constant the floating up of the critical states in energy without merging is observed. This behavior is similar to the levitation scenario proposed for the continuum model.

Gap Acceptance Behavior Model for Non-signalized

OpenAIRE

Fajaruddin Bin Mustakim

2015-01-01

The paper proposes field studies that were performed to determine the critical gap on the multiple rural roadways Malaysia, at non-signalized T-intersection by using The Raff and Logic Method. Critical gap between passenger car and motorcycle have been determined.   There are quite number of studied doing gap acceptance behavior model for passenger car however still few research on gap acceptance behavior model for motorcycle. Thus in this paper, logistic regression models were developed to p...

eSPEM - A SPEM Extension for Enactable Behavior Modeling

Science.gov (United States)

Ellner, Ralf; Al-Hilank, Samir; Drexler, Johannes; Jung, Martin; Kips, Detlef; Philippsen, Michael

OMG's SPEM - by means of its (semi-)formal notation - allows for a detailed description of development processes and methodologies, but can only be used for a rather coarse description of their behavior. Concepts for a more fine-grained behavior model are considered out of scope of the SPEM standard and have to be provided by other standards like BPDM/BPMN or UML. However, a coarse granularity of the behavior model often impedes a computer-aided enactment of a process model. Therefore, in this paper we present eSPEM, an extension of SPEM, that is based on the UML meta-model and focused on fine-grained behavior and life-cycle modeling and thereby supports automated enactment of development processes.

Current-voltage analysis of the record-efficiency CuGaSe2 solar cell: Application of the current separation method and the interface recombination model

International Nuclear Information System (INIS)

Saad, M.; Kasis, A.

2011-01-01

Current-voltage (j-V) characteristics of the record-efficiency CuGaSe 2 solar cell measured under several illumination levels are analyzed using a two-diode equation for a more accurate description of cell behavior. The contribution of each diode to the total cell j-V characteristic under illumination was estimated using the current separation method presented recently. This is performed in an effort to identify the distinctive features of this record-efficiency cell which have led to the up-to-date highest open circuit voltage of V o c = 946 mV and fill factor of FF = 66.5% for CuGaSe 2 solar cells. Furthermore, the interface recombination component of the cell current under illumination is quantitatively discussed applying the interface recombination model presented earlier. (author)

A constitutive model for developing blood clots with various compositions and their nonlinear viscoelastic behavior.

Science.gov (United States)

van Kempen, Thomas H S; Donders, Wouter P; van de Vosse, Frans N; Peters, Gerrit W M

2016-04-01

The mechanical properties determine to a large extent the functioning of a blood clot. These properties depend on the composition of the clot and have been related to many diseases. However, the various involved components and their complex interactions make it difficult at this stage to fully understand and predict properties as a function of the components. Therefore, in this study, a constitutive model is developed that describes the viscoelastic behavior of blood clots with various compositions. Hereto, clots are formed from whole blood, platelet-rich plasma and platelet-poor plasma to study the influence of red blood cells, platelets and fibrin, respectively. Rheological experiments are performed to probe the mechanical behavior of the clots during their formation. The nonlinear viscoelastic behavior of the mature clots is characterized using a large amplitude oscillatory shear deformation. The model is based on a generalized Maxwell model that accurately describes the results for the different rheological experiments by making the moduli and viscosities a function of time and the past and current deformation. Using the same model with different parameter values enables a description of clots with different compositions. A sensitivity analysis is applied to study the influence of parameter variations on the model output. The relative simplicity and flexibility make the model suitable for numerical simulations of blood clots and other materials showing similar behavior.

A Conceptual Model of Investor Behavior

OpenAIRE

Lovric, M.; Kaymak, U.; Spronk, J.

2008-01-01

textabstractBased on a survey of behavioral finance literature, this paper presents a descriptive model of individual investor behavior in which investment decisions are seen as an iterative process of interactions between the investor and the investment environment. This investment process is influenced by a number of interdependent variables and driven by dual mental systems, the interplay of which contributes to boundedly rational behavior where investors use various heuristics and may exh...

Bipolar and unipolar resistive switching behaviors of sol–gel-derived SrTiO3 thin films with different compliance currents

International Nuclear Information System (INIS)

Tang, M H; Wang, Z P; Zeng, Z Q; Xu, X L; Wang, G Y; Zhang, L B; Xiao, Y G; Yang, S B; Jiang, B; Li, J C; He, J

2011-01-01

The SrTiO 3 (STO) thin films on a Pt/Ti/SiO 2 /Si substrate were synthesized using a sol–gel method to form a metal–insulator–metal structure. This device shows the bipolar resistance switching (BRS) behavior for a compliance current I cc of less than 0.1 mA but exhibits soft breakdown at a higher level of compliance current. A transition from the BRS behavior to the stable unipolar resistive switching behavior (URS) was also observed. We found that the BRS behavior may be controlled by the structure interface while the URS behavior is likely bulk controlled. Our study indicates that the external compliance current is a key factor in resistance switching phenomenon of STO thin films

Information Behavior: A Socio-Cognitive Ability

Directory of Open Access Journals (Sweden)

Amanda Spink

2007-04-01

Full Text Available How has human information behavior evolved? Our paper explores this question in the form of notions, models and theories about the relationship between information behavior and human evolution. Alexander's Ecological Dominance and Social Competition/Cooperation (EDSC model currently provides the most comprehensive overview of human traits in the development of a theory of human evolution and sociality. His model provides a basis for explaining the evolution of human socio-cognitive abilities, including ecological dominance, and social competition/cooperation. Our paper examines the human trait of information behavior as a socio-cognitive ability related to ecological dominance, and social competition/cooperation. The paper first outlines what is meant by information behavior from various interdisciplinary perspectives. We propose that information behavior is a socio-cognitive ability that is related to and enables other socio-cognitive abilities such as human ecological dominance, and social competition/cooperation. The paper reviews the current state of evolutionary approaches to information behavior and future directions for this research

Modeling emergent border-crossing behaviors during pandemics

Science.gov (United States)

Santos, Eunice E.; Santos, Eugene; Korah, John; Thompson, Jeremy E.; Gu, Qi; Kim, Keum Joo; Li, Deqing; Russell, Jacob; Subramanian, Suresh; Zhang, Yuxi; Zhao, Yan

2013-06-01

Modeling real-world scenarios is a challenge for traditional social science researchers, as it is often hard to capture the intricacies and dynamisms of real-world situations without making simplistic assumptions. This imposes severe limitations on the capabilities of such models and frameworks. Complex population dynamics during natural disasters such as pandemics is an area where computational social science can provide useful insights and explanations. In this paper, we employ a novel intent-driven modeling paradigm for such real-world scenarios by causally mapping beliefs, goals, and actions of individuals and groups to overall behavior using a probabilistic representation called Bayesian Knowledge Bases (BKBs). To validate our framework we examine emergent behavior occurring near a national border during pandemics, specifically the 2009 H1N1 pandemic in Mexico. The novelty of the work in this paper lies in representing the dynamism at multiple scales by including both coarse-grained (events at the national level) and finegrained (events at two separate border locations) information. This is especially useful for analysts in disaster management and first responder organizations who need to be able to understand both macro-level behavior and changes in the immediate vicinity, to help with planning, prevention, and mitigation. We demonstrate the capabilities of our framework in uncovering previously hidden connections and explanations by comparing independent models of the border locations with their fused model to identify emergent behaviors not found in either independent location models nor in a simple linear combination of those models.

A computational model for lower hybrid current drive

International Nuclear Information System (INIS)

Englade, R.C.; Bonoli, P.T.; Porkolab, M.

1983-01-01

A detailed simulation model for lower hybrid (LH) current drive in toroidal devices is discussed. This model accounts reasonably well for the magnitude of radio frequency (RF) current observed in the PLT and Alcator C devices. It also reproduces the experimental dependencies of RF current generation on toroidal magnetic field and has provided insights about mechanisms which may underlie the observed density limit of current drive. (author)

Modelling of the ring current in Saturn's magnetosphere

Directory of Open Access Journals (Sweden)

G. Giampieri

2004-01-01

Full Text Available The existence of a ring current inside Saturn's magnetosphere was first suggested by Smith et al. (1980 and Ness et al. (1981, 1982, in order to explain various features in the magnetic field observations from the Pioneer 11 and Voyager 1 and 2 spacecraft. Connerney et al. (1983 formalized the equatorial current model, based on previous modelling work of Jupiter's current sheet and estimated its parameters from the two Voyager data sets. Here, we investigate the model further, by reconsidering the data from the two Voyager spacecraft, as well as including the Pioneer 11 flyby data set. First, we obtain, in closed form, an analytic expression for the magnetic field produced by the ring current. We then fit the model to the external field, that is the difference between the observed field and the internal magnetic field, considering all the available data. In general, through our global fit we obtain more accurate parameters, compared to previous models. We point out differences between the model's parameters for the three flybys, and also investigate possible deviations from the axial and planar symmetries assumed in the model. We conclude that an accurate modelling of the Saturnian disk current will require taking into account both of the temporal variations related to the condition of the magnetosphere, as well as non-axisymmetric contributions due to local time effects. Key words. Magnetospheric physics (current systems; planetary magnetospheres; plasma sheet

Modeling and simulating human teamwork behaviors using intelligent agents

Science.gov (United States)

Fan, Xiaocong; Yen, John

2004-12-01

Among researchers in multi-agent systems there has been growing interest in using intelligent agents to model and simulate human teamwork behaviors. Teamwork modeling is important for training humans in gaining collaborative skills, for supporting humans in making critical decisions by proactively gathering, fusing, and sharing information, and for building coherent teams with both humans and agents working effectively on intelligence-intensive problems. Teamwork modeling is also challenging because the research has spanned diverse disciplines from business management to cognitive science, human discourse, and distributed artificial intelligence. This article presents an extensive, but not exhaustive, list of work in the field, where the taxonomy is organized along two main dimensions: team social structure and social behaviors. Along the dimension of social structure, we consider agent-only teams and mixed human-agent teams. Along the dimension of social behaviors, we consider collaborative behaviors, communicative behaviors, helping behaviors, and the underpinning of effective teamwork-shared mental models. The contribution of this article is that it presents an organizational framework for analyzing a variety of teamwork simulation systems and for further studying simulated teamwork behaviors.

Driver's Behavior Modeling Using Fuzzy Logic

Directory of Open Access Journals (Sweden)

Sehraneh Ghaemi

2010-01-01

Full Text Available In this study, we propose a hierarchical fuzzy system for human in a driver-vehicle-environment system to model takeover by different drivers. The driver's behavior is affected by the environment. The climate, road and car conditions are included in fuzzy modeling. For obtaining fuzzy rules, experts' opinions are benefited by means of questionnaires on effects of parameters such as climate, road and car conditions on driving capabilities. Also the precision, age and driving individuality are used to model the driver's behavior. Three different positions are considered for driving and decision making. A fuzzy model called Model I is presented for modeling the change of steering angle and speed control by considering time distances with existing cars in these three positions, the information about the speed and direction of car, and the steering angle of car. Also we obtained two other models based on fuzzy rules called Model II and Model III by using Sugeno fuzzy inference. Model II and Model III have less linguistic terms than Model I for the steering angle and direction of car. The results of three models are compared for a driver who drives based on driving laws.

Modeling and control of a proton exchange membrane fuel cell with the air compressor according to requested electrical current

Directory of Open Access Journals (Sweden)

Malekbala Mohammad Rahim

2015-01-01

Full Text Available The aim of this paper is to design and investigate the dynamic behavior of a PEM fuel cell system. Dynamic analysis of a PEM fuel cell system has been done in Matlab\\Simulink software according to electrical current that has been applied from hybrid system. In addition, dynamical fuel cell system has been explained according to oriented control that is started from air injection compressor model. Also hydrogen valve actuator has been controlled according to the compressor model. The results of the fuel cell dynamic model as well as the applied compressor model are fully validated based on the available results in the open literature. Finally, the effects of several operating parameters of the fuel cell system such as anode and cathode pressures, cell voltage, compressor voltage, compressor mass flow rate variation with respect to inlet pressure ratio, net and stack powers on the dynamic behavior of the hybrid system are investigated. The results show that the model can predict the dynamic behavior of the fuel cell system accurately and it can be used directly for any control purposes.

Multi-step resistive switching behavior of Li-doped ZnO resistance random access memory device controlled by compliance current

International Nuclear Information System (INIS)

Lin, Chun-Cheng; Tang, Jian-Fu; Su, Hsiu-Hsien; Hong, Cheng-Shong; Huang, Chih-Yu; Chu, Sheng-Yuan

2016-01-01

The multi-step resistive switching (RS) behavior of a unipolar Pt/Li 0.06 Zn 0.94 O/Pt resistive random access memory (RRAM) device is investigated. It is found that the RRAM device exhibits normal, 2-, 3-, and 4-step RESET behaviors under different compliance currents. The transport mechanism within the device is investigated by means of current-voltage curves, in-situ transmission electron microscopy, and electrochemical impedance spectroscopy. It is shown that the ion transport mechanism is dominated by Ohmic behavior under low electric fields and the Poole-Frenkel emission effect (normal RS behavior) or Li + ion diffusion (2-, 3-, and 4-step RESET behaviors) under high electric fields.

Aggressive behavior and anaplasia in pleomorphic xanthoastrocytoma: a plea for a revision of the current WHO classification.

Science.gov (United States)

Kahramancetin, Nesibe; Tihan, Tarik

2013-11-01

Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic neoplasm that commonly affects children and young adults, and presents with seizures. PXA is typically supratentorial with a predilection to the temporal lobe, and often involves the cortex and the meninges. PXAs have a favorable prognosis with a 10-year survival probability of >70%, and are WHO grade II neoplasms. Recent observations and studies demonstrate that PXAs are clinically, histologically and genetically distinct. Some PXAs recur and exhibit aggressive clinical behavior. In such cases, certain histological and clinical factors could account for the aggressive behavior. However, the histological features that predict adverse outcome are poorly defined. In the current WHO classification of CNS tumors, there is no option for a high-grade PXA, even if the tumor had numerous recurrences and poor outcome. In this review, we focus on aggressive clinical behavior and anaplasia in PXA, and discuss how our current experience suggests modifications in the current WHO classification. We also review recent discoveries on the molecular characteristics of PXA that could help us better understand their biological behavior.

Tax Compliance Models: From Economic to Behavioral Approaches

Directory of Open Access Journals (Sweden)

Larissa Margareta BĂTRÂNCEA

2012-06-01

Full Text Available The paper reviews the models of tax compliance with an emphasis on economic and behavioral perspectives. Although the standard tax evasion model of Allingham and Sandmo and other similar economic models capture some important aspects of tax compliance (i.e., taxpayers’ response to increases in tax rate, audit probability, penalty rate they do not suffice the need for an accurate prediction of taxpayers’ behavior. The reason is that they do not offer a comprehensive perspective on the sociological and psychological factors which shape compliance (i.e., attitudes, beliefs, norms, perceptions, motivations. Therefore, the researchers have considered examining taxpayers’ inner motivations, beliefs, perceptions, attitudes in order to accurately predict taxpayers’ behavior. As a response to their quest, behavioral models of tax compliance have emerged. Among the sociological and psychological factors which shape tax compliance, the ‘slippery slope’ framework singles out trust in authorities and the perception of the power of authorities. The aim of the paper is to contribute to the understanding of the reasons for which there is a need for a tax compliance model which incorporates both economic and behavioral features and why governments and tax authorities should consider these models when designing fiscal policies.

Trojan detection model based on network behavior analysis

International Nuclear Information System (INIS)

Liu Junrong; Liu Baoxu; Wang Wenjin

2012-01-01

Based on the analysis of existing Trojan detection technology, this paper presents a Trojan detection model based on network behavior analysis. First of all, we abstract description of the Trojan network behavior, then according to certain rules to establish the characteristic behavior library, and then use the support vector machine algorithm to determine whether a Trojan invasion. Finally, through the intrusion detection experiments, shows that this model can effectively detect Trojans. (authors)

Mechanical behavior of the ATLAS B0 model coil

CERN Document Server

Foussat, A; Acerbi, E; Alessandria, F; Berthier, R; Broggi, F; Daël, A; Dudarev, A; Mayri, C; Miele, P; Reytier, M; Rossi, L; Sorbi, M; Sun, Z; ten Kate, H H J; Vanenkov, I; Volpini, G

2002-01-01

The ATLAS B0 model coil has been developed and constructed to verify the design parameters and the manufacture techniques of the Barrel Toroid coils (BT) that are under construction for the ATLAS Detector. Essential for successful operation is the mechanical behavior of the superconducting coil and its support structure. In the ATLAS magnet test facility, a magnetic mirror is used to reproduce in the model coil the electromagnetic forces of the BT coils when assembled in the final Barrel Toroid magnet system. The model coil is extensively equipped with mechanical instrumentation to monitor stresses and force levels as well as contraction during a cooling down and excitation up to nominal current. The installed set up of strain gauges, position sensors and capacitive force transducers is presented. Moreover the first mechanical results in terms of expected main stress, strain and deformation values are presented based on detailed mechanical analysis of the design. (7 refs).

Modelling aerosol behavior in reactor cooling systems

International Nuclear Information System (INIS)

McDonald, B.H.

1990-01-01

This paper presents an overview of some of the areas of concern in using computer codes to model fission-product aerosol behavior in the reactor cooling system (RCS) of a water-cooled nuclear reactor during a loss-of-coolant accident. The basic physical processes that require modelling include: fission product release and aerosol formation in the reactor core, aerosol transport and deposition in the reactor core and throughout the rest of the RCS, and the interaction between aerosol transport processes and the thermalhydraulics. In addition to these basic physical processes, chemical reactions can have a large influence on the nature of the aerosol and its behavior in the RCS. The focus is on the physics and the implications of numerical methods used in the computer codes to model aerosol behavior in the RCS

Model of unplanned smoking initiation of children and adolescents: an integrated stage model of smoking behavior.

Science.gov (United States)

Kremers, S P J; Mudde, A N; De Vries, H

2004-05-01

Two lines of psychological research have attempted to spell out the stages of adolescent smoking initiation. The first has focused on behavioral stages of smoking initiation, while the second line emphasized motivational stages. A large international sample of European adolescents (N = 10,170, mean age = 13.3 years) was followed longitudinally. Self-reported motivational and behavioral stages of smoking initiation were integrated, leading to the development of the Model of Unplanned Smoking Initiation of Children and Adolescents (MUSICA). The MUSICA postulates that youngsters experiment with smoking while they are in an unmotivated state as regards their plans for smoking regularly in the future. More than 95% of the total population resided in one of the seven stages distinguished by MUSICA. The probability of starting to smoke regularly during the 12 months follow-up period increased with advanced stage assignment at baseline. Unique social cognitive predictors of stage progression from the various stages were identified, but effect sizes of predictors of transitions were small. The integration of motivational and behavioral dimensions improves our understanding of the process of smoking initiation. In contrast to current theories of smoking initiation, adolescent uptake of smoking behavior was found to be an unplanned action.

Phantomlike behavior in a brane-world model with curvature effects

International Nuclear Information System (INIS)

Bouhmadi-Lopez, Mariam; Moniz, Paulo Vargas

2008-01-01

Recent observational evidence seems to allow the possibility that our Universe may currently be under a dark energy effect of a phantom nature. A suitable effective phantom fluid behavior can emerge in brane cosmology; in particular, within the normal non-self-accelerating Dvali-Gabadadze-Porrati branch, without any exotic matter and due to curvature effects from induced gravity. The phantomlike behavior is based in defining an effective energy density that grows as the brane expands. This effective description breaks down at some point in the past when the effective energy density becomes negative and the effective equation of state parameter blows up. In this paper we investigate if the phantomlike regime can be enlarged by the inclusion of a Gauss-Bonnet (GB) term into the bulk. The motivation is that such a GB component would model additional curvature effects on the brane setting. More precisely, our aim is to determine if the GB term, dominating and modifying the early behavior of the brane universe, may eventually extend the regime of validity of the phantom mimicry on the brane. However, we show that the opposite occurs: the GB effect seems instead to induce a breakdown of the phantomlike behavior at an even smaller redshift.

Critical-state model for the determination of critical currents in disk-shaped superconductors

International Nuclear Information System (INIS)

Frankel, D.J.

1979-01-01

A series of experiments has been carried out on the flux trapping and shielding capabilities of a flat strip of Nb-Ti/Cu composite material. A circular piece of material from the strip was tested in a uniform field directed perpendicularly to the surface of the sample. Profiles of the normal component of the field along the sample diameter were measured. The critical-state model was adapted for this geometry and proved capable of reproducing the measured field profiles. Model curves agreed well with experimental field profiles generated when the full sample was in the critical state, when only a portion of the sample was in the critical state, and when profiles were obtained after the direction of the rate change of the magnetic field was reversed. The adaption of the critical-state model to disk geometry provides a possible method either to derive values of the critical current from measurements of field profiles above thin flat samples, or to predict the trapping and shielding behavior of such samples if the critical current is already known. This method of determining critical currents does not require that samples be formed into narrow strips or wires, as is required for direct measurements of J/sub c/, or into tubes or cylinders, as is usually required for magnetization-type measurements. Only a relatively small approximately circular piece of material is needed. The method relies on induced currents, so there is no need to pass large currents into the sample. The field-profile measurements are easily performed with expensive Hall probes and do not require detection of the resistive transition of the superconductor

Current-voltage model of LED light sources

DEFF Research Database (Denmark)

Beczkowski, Szymon; Munk-Nielsen, Stig

2012-01-01

Amplitude modulation is rarely used for dimming light-emitting diodes in polychromatic luminaires due to big color shifts caused by varying magnitude of LED driving current and nonlinear relationship between intensity of a diode and driving current. Current-voltage empirical model of light...

Explaining clinical behaviors using multiple theoretical models

Directory of Open Access Journals (Sweden)

Eccles Martin P

2012-10-01

Full Text Available Abstract Background In the field of implementation research, there is an increased interest in use of theory when designing implementation research studies involving behavior change. In 2003, we initiated a series of five studies to establish a scientific rationale for interventions to translate research findings into clinical practice by exploring the performance of a number of different, commonly used, overlapping behavioral theories and models. We reflect on the strengths and weaknesses of the methods, the performance of the theories, and consider where these methods sit alongside the range of methods for studying healthcare professional behavior change. Methods These were five studies of the theory-based cognitions and clinical behaviors (taking dental radiographs, performing dental restorations, placing fissure sealants, managing upper respiratory tract infections without prescribing antibiotics, managing low back pain without ordering lumbar spine x-rays of random samples of primary care dentists and physicians. Measures were derived for the explanatory theoretical constructs in the Theory of Planned Behavior (TPB, Social Cognitive Theory (SCT, and Illness Representations specified by the Common Sense Self Regulation Model (CSSRM. We constructed self-report measures of two constructs from Learning Theory (LT, a measure of Implementation Intentions (II, and the Precaution Adoption Process. We collected data on theory-based cognitions (explanatory measures and two interim outcome measures (stated behavioral intention and simulated behavior by postal questionnaire survey during the 12-month period to which objective measures of behavior (collected from routine administrative sources were related. Planned analyses explored the predictive value of theories in explaining variance in intention, behavioral simulation and behavior. Results Response rates across the five surveys ranged from 21% to 48%; we achieved the target sample size for three of

Explaining clinical behaviors using multiple theoretical models.

Science.gov (United States)

Eccles, Martin P; Grimshaw, Jeremy M; MacLennan, Graeme; Bonetti, Debbie; Glidewell, Liz; Pitts, Nigel B; Steen, Nick; Thomas, Ruth; Walker, Anne; Johnston, Marie

2012-10-17

In the field of implementation research, there is an increased interest in use of theory when designing implementation research studies involving behavior change. In 2003, we initiated a series of five studies to establish a scientific rationale for interventions to translate research findings into clinical practice by exploring the performance of a number of different, commonly used, overlapping behavioral theories and models. We reflect on the strengths and weaknesses of the methods, the performance of the theories, and consider where these methods sit alongside the range of methods for studying healthcare professional behavior change. These were five studies of the theory-based cognitions and clinical behaviors (taking dental radiographs, performing dental restorations, placing fissure sealants, managing upper respiratory tract infections without prescribing antibiotics, managing low back pain without ordering lumbar spine x-rays) of random samples of primary care dentists and physicians. Measures were derived for the explanatory theoretical constructs in the Theory of Planned Behavior (TPB), Social Cognitive Theory (SCT), and Illness Representations specified by the Common Sense Self Regulation Model (CSSRM). We constructed self-report measures of two constructs from Learning Theory (LT), a measure of Implementation Intentions (II), and the Precaution Adoption Process. We collected data on theory-based cognitions (explanatory measures) and two interim outcome measures (stated behavioral intention and simulated behavior) by postal questionnaire survey during the 12-month period to which objective measures of behavior (collected from routine administrative sources) were related. Planned analyses explored the predictive value of theories in explaining variance in intention, behavioral simulation and behavior. Response rates across the five surveys ranged from 21% to 48%; we achieved the target sample size for three of the five surveys. For the predictor variables

Approximating Behavioral Equivalence of Models Using Top-K Policy Paths

DEFF Research Database (Denmark)

Zeng, Yifeng; Chen, Yingke; Prashant, Doshi

2011-01-01

Decision making and game play in multiagent settings must often contend with behavioral models of other agents in order to predict their actions. One approach that reduces the complexity of the unconstrained model space is to group models that tend to be behaviorally equivalent. In this paper, we...... seek to further compress the model space by introducing an approximate measure of behavioral equivalence and using it to group models....

General Potential-Current Model and Validation for Electrocoagulation

International Nuclear Information System (INIS)

Dubrawski, Kristian L.; Du, Codey; Mohseni, Madjid

2014-01-01

A model relating potential and current in continuous parallel plate iron electrocoagulation (EC) was developed for application in drinking water treatment. The general model can be applied to any EC parallel plate system relying only on geometric and tabulated input variables without the need of system-specific experimentally derived constants. For the theoretical model, the anode and cathode were vertically divided into n equipotential segments in a single pass, upflow, and adiabatic EC reactor. Potential and energy balances were simultaneously solved at each vertical segment, which included the contribution of ionic concentrations, solution temperature and conductivity, cathodic hydrogen flux, and gas/liquid ratio. We experimentally validated the numerical model with a vertical upflow EC reactor using a 24 cm height 99.99% pure iron anode divided into twelve 2 cm segments. Individual experimental currents from each segment were summed to determine total current, and compared with the theoretically derived value. Several key variables were studied to determine their impact on model accuracy: solute type, solute concentration, current density, flow rate, inter-electrode gap, and electrode surface condition. Model results were in good agreement with experimental values at cell potentials of 2-20 V (corresponding to a current density range of approximately 50-800 A/m 2 ), with mean relative deviation of 9% for low flow rate, narrow electrode gap, polished electrodes, and 150 mg/L NaCl. Highest deviation occurred with a large electrode gap, unpolished electrodes, and Na 2 SO 4 electrolyte, due to parasitic H 2 O oxidation and less than unity current efficiency. This is the first general model which can be applied to any parallel plate EC system for accurate electrochemical voltage or current prediction

Low-temperature behavior of core-softened models: Water and silica behavior

International Nuclear Information System (INIS)

Jagla, E. A.

2001-01-01

A core-softened model of a glass forming fluid is numerically studied in the limit of very low temperatures. The model shows two qualitatively different behaviors depending on the strength of the attraction between particles. For no or low attraction, the changes of density as a function of pressure are smooth, although hysteretic due to mechanical metastabilities. For larger attraction, sudden changes of density upon compressing and decompressing occur. This global mechanical instability is correlated to the existence of a thermodynamic first-order amorphous-amorphous transition. The two different behaviors obtained correspond qualitatively to the different phenomenology observed in silica and water

Relevance of behavioral and social models to the study of consumer energy decision making and behavior

Energy Technology Data Exchange (ETDEWEB)

Burns, B.A.

1980-11-01

This report reviews social and behavioral science models and techniques for their possible use in understanding and predicting consumer energy decision making and behaviors. A number of models and techniques have been developed that address different aspects of the decision process, use different theoretical bases and approaches, and have been aimed at different audiences. Three major areas of discussion were selected: (1) models of adaptation to social change, (2) decision making and choice, and (3) diffusion of innovation. Within these three areas, the contributions of psychologists, sociologists, economists, marketing researchers, and others were reviewed. Five primary components of the models were identified and compared. The components are: (1) situational characteristics, (2) product characteristics, (3) individual characteristics, (4) social influences, and (5) the interaction or decision rules. The explicit use of behavioral and social science models in energy decision-making and behavior studies has been limited. Examples are given of a small number of energy studies which applied and tested existing models in studying the adoption of energy conservation behaviors and technologies, and solar technology.

Multi-step resistive switching behavior of Li-doped ZnO resistance random access memory device controlled by compliance current

Energy Technology Data Exchange (ETDEWEB)

Lin, Chun-Cheng [Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan (China); Department of Mathematic and Physical Sciences, R.O.C. Air Force Academy, Kaohsiung 820, Taiwan (China); Tang, Jian-Fu; Su, Hsiu-Hsien [Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan (China); Hong, Cheng-Shong; Huang, Chih-Yu [Department of Electronic Engineering, National Kaohsiung Normal University, Kaohsiung 802, Taiwan (China); Chu, Sheng-Yuan, E-mail: chusy@mail.ncku.edu.tw [Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan 701, Taiwan (China)

2016-06-28

The multi-step resistive switching (RS) behavior of a unipolar Pt/Li{sub 0.06}Zn{sub 0.94}O/Pt resistive random access memory (RRAM) device is investigated. It is found that the RRAM device exhibits normal, 2-, 3-, and 4-step RESET behaviors under different compliance currents. The transport mechanism within the device is investigated by means of current-voltage curves, in-situ transmission electron microscopy, and electrochemical impedance spectroscopy. It is shown that the ion transport mechanism is dominated by Ohmic behavior under low electric fields and the Poole-Frenkel emission effect (normal RS behavior) or Li{sup +} ion diffusion (2-, 3-, and 4-step RESET behaviors) under high electric fields.

Modeling irrigation behavior in groundwater systems

Science.gov (United States)

Foster, Timothy; Brozović, Nicholas; Butler, Adrian P.

2014-08-01

Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas High Plains region of the United States we predict optimal irrigation strategies under variable levels of groundwater supply, and assess the limits of existing models for predicting land and groundwater use decisions by farmers. Our results show that irrigation behavior exhibits complex nonlinear responses to changes in groundwater availability. Declining well yields induce large reductions in the optimal size of irrigated area and irrigation use as constraints on instantaneous application rates limit the ability to maintain sufficient soil moisture to avoid negative impacts on crop yield. We demonstrate that this important behavioral response to limited groundwater availability is not captured by existing modeling approaches, which therefore may be unreliable predictors of irrigation demand, agricultural profitability, and resilience to climate change and aquifer depletion.

Analytic modeling of axisymmetric disruption halo currents

International Nuclear Information System (INIS)

Humphreys, D.A.; Kellman, A.G.

1999-01-01

Currents which can flow in plasma facing components during disruptions pose a challenge to the design of next generation tokamaks. Induced toroidal eddy currents and both induced and conducted poloidal ''halo'' currents can produce design-limiting electromagnetic loads. While induction of toroidal and poloidal currents in passive structures is a well-understood phenomenon, the driving terms and scalings for poloidal currents flowing on open field lines during disruptions are less well established. A model of halo current evolution is presented in which the current is induced in the halo by decay of the plasma current and change in enclosed toroidal flux while being convected into the halo from the core by plasma motion. Fundamental physical processes and scalings are described in a simplified analytic version of the model. The peak axisymmetric halo current is found to depend on halo and core plasma characteristics during the current quench, including machine and plasma dimensions, resistivities, safety factor, and vertical stability growth rate. Two extreme regimes in poloidal halo current amplitude are identified depending on the minimum halo safety factor reached during the disruption. A 'type I' disruption is characterized by a minimum safety factor that remains relatively high (typically 2 - 3, comparable to the predisruption safety factor), and a relatively low poloidal halo current. A 'type II' disruption is characterized by a minimum safety factor comparable to unity and a relatively high poloidal halo current. Model predictions for these two regimes are found to agree well with halo current measurements from vertical displacement event disruptions in DIII-D [T. S. Taylor, K. H. Burrell, D. R. Baker, G. L. Jackson, R. J. La Haye, M. A. Mahdavi, R. Prater, T. C. Simonen, and A. D. Turnbull, open-quotes Results from the DIII-D Scientific Research Program,close quotes in Proceedings of the 17th IAEA Fusion Energy Conference, Yokohama, 1998, to be published in

Cognitive-Behavioral Grief Therapy: The ABC Model of Rational-Emotion Behavior Therapy

Directory of Open Access Journals (Sweden)

Ruth Malkinson

2010-12-01

Full Text Available The article briefly reviews the changes that occurred in the field of grief and bereavement, viewing it as a process of searching for a "rational" meaning to life without the deceased in line with the concept of continuing bonds and thus replacing that of Fred’s concept of decathexis. Cognitive-behavioral therapy (CBT evidenced-based studies for PTSD and complicated grief and the Cognitive-behavioral therapy − Rational-emotion behavior therapy (CBT-REBT model for grief are reviewed. The focus of intervention based on CBT-REBT is to facilitate a healthy adaptation to loss following death. A distinction is made between rational (adaptive and irrational (maladaptive grief processes. Case example illustrating the application of the model specifically a dialogue with repetitive thoughts, are presented.

Developing robotic behavior using a genetic programming model

International Nuclear Information System (INIS)

Pryor, R.J.

1998-01-01

This report describes the methodology for using a genetic programming model to develop tracking behaviors for autonomous, microscale robotic vehicles. The use of such vehicles for surveillance and detection operations has become increasingly important in defense and humanitarian applications. Through an evolutionary process similar to that found in nature, the genetic programming model generates a computer program that when downloaded onto a robotic vehicle's on-board computer will guide the robot to successfully accomplish its task. Simulations of multiple robots engaged in problem-solving tasks have demonstrated cooperative behaviors. This report also discusses the behavior model produced by genetic programming and presents some results achieved during the study

Microscopic models for bridging electrostatics and currents

Science.gov (United States)

Borghi, L.; DeAmbrosis, A.; Mascheretti, P.

2007-03-01

A teaching sequence based on the use of microscopic models to link electrostatic phenomena with direct currents is presented. The sequence, devised for high school students, was designed after initial work carried out with student teachers attending a school of specialization for teaching physics at high school, at the University of Pavia. The results obtained with them are briefly presented, because they directed our steps for the development of the teaching sequence. For both the design of the experiments and their interpretation, we drew inspiration from the original works of Alessandro Volta; in addition, a structural model based on the particular role of electrons as elementary charges both in electrostatic phenomena and in currents was proposed. The teaching sequence starts from experiments on charging objects by rubbing and by induction, and engages students in constructing microscopic models to interpret their observations. By using these models and by closely examining the ideas of tension and capacitance, the students acknowledge that a charging (or discharging) process is due to the motion of electrons that, albeit for short time intervals, represent a current. Finally, they are made to see that the same happens in transients of direct current circuits.

A phenomenological memristor model for synaptic memory and learning behaviors

Institute of Scientific and Technical Information of China (English)

Nan Shao; Sheng-Bing Zhang; Shu-Yuan Shao

2017-01-01

Properties that are similar to the memory and learning functions in biological systems have been observed and reported in the experimental studies of memristors fabricated by different materials.These properties include the forgetting effect,the transition from short-term memory (STM) to long-term memory (LTM),learning-experience behavior,etc.The mathematical model of this kind of memristor would be very important for its theoretical analysis and application design.In our analysis of the existing memristor model with these properties,we find that some behaviors of the model are inconsistent with the reported experimental observations.A phenomenological memristor model is proposed for this kind of memristor.The model design is based on the forgetting effect and STM-to-LTM transition since these behaviors are two typical properties of these memristors.Further analyses of this model show that this model can also be used directly or modified to describe other experimentally observed behaviors.Simulations show that the proposed model can give a better description of the reported memory and learning behaviors of this kind of memristor than the existing model.

Theoretical models of drivers behavior on the road

Directory of Open Access Journals (Sweden)

Marcin Piotr Biernacki

2017-06-01

Full Text Available Understanding of mechanisms and factors responsible for the driver behavior on the road is the subject of ongoing interest to transportation psychologists, occupational doctors and engineers. Models of driver behavior are a key point for the understanding the mechanisms and factors which may cause limitations to the optimal functioning on the road. They also systematize knowledge about the factors responsible for the behavior of the driver and thus constitute a starting point for formulating empirical or diagnostic hypotheses. The aim of this study is to present models of driver behavior from the descriptive and functional perspectives. Med Pr 2017;68(3:401–411

Scanpath Based N-Gram Models for Predicting Reading Behavior

DEFF Research Database (Denmark)

Mishra, Abhijit; Bhattacharyya, Pushpak; Carl, Michael

2013-01-01

Predicting reading behavior is a difficult task. Reading behavior depends on various linguistic factors (e.g. sentence length, structural complexity etc.) and other factors (e.g individual's reading style, age etc.). Ideally, a reading model should be similar to a language model where the model i...

Numerical modeling of transformer inrush currents

Energy Technology Data Exchange (ETDEWEB)

Cardelli, E. [Department of Industrial Engineering, University of Perugia, I-06125 Perugia (Italy); Center for Electric and Magnetic Applied Research (Italy); Faba, A., E-mail: faba@unipg.it [Department of Industrial Engineering, University of Perugia, I-06125 Perugia (Italy); Center for Electric and Magnetic Applied Research (Italy)

2014-02-15

This paper presents an application of a vector hysteresis model to the prediction of the inrush current due the arbitrary initial excitation of a transformer after a fault. The approach proposed seems promising in order to predict the transient overshoot in current and the optimal time to close the circuit after the fault.

Some current dimensions of the behavioral economics of health-related behavior change.

Science.gov (United States)

Bickel, Warren K; Moody, Lara; Higgins, Stephen T

2016-11-01

Health-related behaviors such as tobacco, alcohol and other substance use, poor diet and physical inactivity, and risky sexual practices are important targets for research and intervention. Health-related behaviors are especially pertinent targets in the United States, which lags behind most other developed nations on common markers of population health. In this essay we examine the application of behavioral economics, a scientific discipline that represents the intersection of economics and psychology, to the study and promotion of health-related behavior change. More specifically, we review what we consider to be some core dimensions of this discipline when applied to the study health-related behavior change. Behavioral economics (1) provides novel conceptual systems to inform scientific understanding of health behaviors, (2) translates scientific understanding into practical and effective behavior-change interventions, (3) leverages varied aspects of behavior change beyond increases or decreases in frequency, (4) recognizes and exploits trans-disease processes and interventions, and (5) leverages technology in efforts to maximize efficacy, cost effectiveness, and reach. These dimensions are overviewed and their implications for the future of the field discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Behavioral phenotypes of genetic mouse models of autism.

Science.gov (United States)

Kazdoba, T M; Leach, P T; Crawley, J N

2016-01-01

More than a hundred de novo single gene mutations and copy-number variants have been implicated in autism, each occurring in a small subset of cases. Mutant mouse models with syntenic mutations offer research tools to gain an understanding of the role of each gene in modulating biological and behavioral phenotypes relevant to autism. Knockout, knockin and transgenic mice incorporating risk gene mutations detected in autism spectrum disorder and comorbid neurodevelopmental disorders are now widely available. At present, autism spectrum disorder is diagnosed solely by behavioral criteria. We developed a constellation of mouse behavioral assays designed to maximize face validity to the types of social deficits and repetitive behaviors that are central to an autism diagnosis. Mouse behavioral assays for associated symptoms of autism, which include cognitive inflexibility, anxiety, hyperactivity, and unusual reactivity to sensory stimuli, are frequently included in the phenotypic analyses. Over the past 10 years, we and many other laboratories around the world have employed these and additional behavioral tests to phenotype a large number of mutant mouse models of autism. In this review, we highlight mouse models with mutations in genes that have been identified as risk genes for autism, which work through synaptic mechanisms and through the mTOR signaling pathway. Robust, replicated autism-relevant behavioral outcomes in a genetic mouse model lend credence to a causal role for specific gene contributions and downstream biological mechanisms in the etiology of autism. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Current Analysis and Modeling of Fullerene Single-Electron Transistor at Room Temperature

Science.gov (United States)

Khadem Hosseini, Vahideh; Ahmadi, Mohammad Taghi; Afrang, Saeid; Ismail, Razali

2017-07-01

Single-electron transistors (SETs) are interesting electronic devices that have become key elements in modern nanoelectronic systems. SETs operate quickly because they use individual electrons, with the number transferred playing a key role in their switching behavior. However, rapid transmission of electrons can cause their accumulation at the island, affecting the I- V characteristic. Selection of fullerene as a nanoscale zero-dimensional material with high stability, and controllable size in the fabrication process, can overcome this charge accumulation issue and improve the reliability of SETs. Herein, the current in a fullerene SET is modeled and compared with experimental data for a silicon SET. Furthermore, a weaker Coulomb staircase and improved reliability are reported. Moreover, the applied gate voltage and fullerene diameter are found to be directly associated with the I- V curve, enabling the desired current to be achieved by controlling the fullerene diameter.

Model for the resistive critical current transition in composite superconductors

International Nuclear Information System (INIS)

Warnes, W.H.

1988-01-01

Much of the research investigating technological type-II superconducting composites relies on the measurement of the resistive critical current transition. We have developed a model for the resistive transition which improves on older models by allowing for the very different nature of monofilamentary and multifilamentary composite structures. The monofilamentary model allows for axial current flow around critical current weak links in the superconducting filament. The multifilamentary model incorporates an additional radial current transfer between neighboring filaments. The development of both models is presented. It is shown that the models are useful for extracting more information from the experimental data than was formerly possible. Specific information obtainable from the experimental voltage-current characteristic includes the distribution of critical currents in the composite, the average critical current of the distribution, the range of critical currents in the composite, the field and temperature dependence of the distribution, and the fraction of the composite dissipating energy in flux flow at any current. This additional information about the distribution of critical currents may be helpful in leading toward a better understanding of flux pinning in technological superconductors. Comparison of the models with several experiments is given and shown to be in reasonable agreement. Implications of the models for the measurement of critical currents in technological composites is presented and discussed with reference to basic flux pinning studies in such composites

Modeling electric bicycle's lane-changing and retrograde behaviors

Science.gov (United States)

Tang, Tie-Qiao; Luo, Xiao-Feng; Zhang, Jian; Chen, Liang

2018-01-01

Recently, electric bicycle (EB) has been one important traffic tool due to its own merits. However, EB's motion behaviors (especially at a signalized/non-signalized intersection) are more complex than those of vehicle since it always has lane-changing and retrograde behaviors. In this paper, we propose a model to explore EB's lane-changing and retrograde behaviors on a road with a signalized intersection. The numerical results indicate that the proposed model can qualitatively describe each EB's lane-changing and retrograde behaviors near a signalized intersection, and that lane-changing and retrograde behaviors have prominent impacts on the signalized intersection (i.e., prominent jams and congestions occur). The above results show that EB should be controlled as a vehicle, i.e., lane-changing and retrograde behaviors at a signalized intersection should strictly be prohibited to improve the operational efficiency and traffic safety at the signalized intersection.

A Culture-Behavior-Brain Loop Model of Human Development.

Science.gov (United States)

Han, Shihui; Ma, Yina

2015-11-01

Increasing evidence suggests that cultural influences on brain activity are associated with multiple cognitive and affective processes. These findings prompt an integrative framework to account for dynamic interactions between culture, behavior, and the brain. We put forward a culture-behavior-brain (CBB) loop model of human development that proposes that culture shapes the brain by contextualizing behavior, and the brain fits and modifies culture via behavioral influences. Genes provide a fundamental basis for, and interact with, the CBB loop at both individual and population levels. The CBB loop model advances our understanding of the dynamic relationships between culture, behavior, and the brain, which are crucial for human phylogeny and ontogeny. Future brain changes due to cultural influences are discussed based on the CBB loop model. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ontology and modeling patterns for state-based behavior representation

Science.gov (United States)

Castet, Jean-Francois; Rozek, Matthew L.; Ingham, Michel D.; Rouquette, Nicolas F.; Chung, Seung H.; Kerzhner, Aleksandr A.; Donahue, Kenneth M.; Jenkins, J. Steven; Wagner, David A.; Dvorak, Daniel L.;

Generalization of exponential based hyperelastic to hyper-viscoelastic model for investigation of mechanical behavior of rate dependent materials.

Science.gov (United States)

Narooei, K; Arman, M

2018-03-01

In this research, the exponential stretched based hyperelastic strain energy was generalized to the hyper-viscoelastic model using the heredity integral of deformation history to take into account the strain rate effects on the mechanical behavior of materials. The heredity integral was approximated by the approach of Goh et al. to determine the model parameters and the same estimation was used for constitutive modeling. To present the ability of the proposed hyper-viscoelastic model, the stress-strain response of the thermoplastic elastomer gel tissue at different strain rates from 0.001 to 100/s was studied. In addition to better agreement between the current model and experimental data in comparison to the extended Mooney-Rivlin hyper-viscoelastic model, a stable material behavior was predicted for pure shear and balance biaxial deformation modes. To present the engineering application of current model, the Kolsky bars impact test of gel tissue was simulated and the effects of specimen size and inertia on the uniform deformation were investigated. As the mechanical response of polyurea was provided over wide strain rates of 0.0016-6500/s, the current model was applied to fit the experimental data. The results were shown more accuracy could be expected from the current research than the extended Ogden hyper-viscoelastic model. In the final verification example, the pig skin experimental data was used to determine parameters of the hyper-viscoelastic model. Subsequently, a specimen of pig skin at different strain rates was loaded to a fixed strain and the change of stress with time (stress relaxation) was obtained. The stress relaxation results were revealed the peak stress increases by applied strain rate until the saturated loading rate and the equilibrium stress with magnitude of 0.281MPa could be reached. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental modeling of eddy current inspection capabilities

International Nuclear Information System (INIS)

Junker, W.R.; Clark, W.G.

1984-01-01

This chapter examines the experimental modeling of eddy current inspection capabilities based upon the use of liquid mercury samples designed to represent metal components containing discontinuities. A brief summary of past work with mercury modeling and a detailed discussion of recent experiments designed to further evaluate the technique are presented. The main disadvantages of the mercury modeling concept are that mercury is toxic and must be handled carefully, liquid mercury can only be used to represent nonferromagnetic materials, and wetting and meniscus problems can distort the effective size of artificial discontinuities. Artificial discontinuities placed in a liquid mercury sample can be used to represent discontinuities in solid metallic structures. Discontinuity size and type cannot be characterized from phase angle and signal amplitude data developed with a surface scanning, pancake-type eddy current probe. It is concluded that the mercury model approach can greatly enhance the overall understanding and applicability of eddy current inspection techniques

Longitudinal testing of the Information-Motivation-Behavioral Skills model of self-care among adults with type 2 diabetes.

Science.gov (United States)

Meunier, Sophie; Coulombe, Simon; Beaulieu, Marie-Dominique; Côté, José; Lespérance, François; Chiasson, Jean-Louis; Bherer, Louis; Lambert, Jean; Houle, Janie

2016-11-01

The study's aim was to test prospective associations between information, motivation, and behavioral skills (IMB model) and self-care behaviors (diet, exercise, and blood glucose testing) among patients with type 2 diabetes. 295 participants were surveyed one (T1), six (T2), and 12 (T3) months after a diabetes course. Cross-lagged panel analyses were performed to test unidirectional and bidirectional relationships between IMB model variables and self-care behaviors. Blood-glucose testing at T1 was positively related to information at T2, which in turn was positively related to blood-glucose testing at T3. Controlled motivation at T1 was positively related to exercise at T2. Autonomous motivation at T2 was positively associated with exercise at T3. There was a positive bidirectional relationship across time between behavioral skills and general diet. Patterns of prospective associations between IMB model variables and diabetes self-care depend on the self-care behavior considered. This model offers an interesting framework for examining how diabetes self-care behaviors evolve. Diabetes education programs should provide information about current health status and promote experiential learning to help patients realize the impact of their behaviors on glycemic control; should foster autonomous motivation for long-term change; and should build on patients' strengths and skills. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Developing custom fire behavior fuel models from ecologically complex fuel structures for upper Atlantic Coastal Plain forests.

Energy Technology Data Exchange (ETDEWEB)

Parresol, Bernard, R.; Scott, Joe, H.; Andreu, Anne; Prichard, Susan; Kurth, Laurie

2012-01-01

Currently geospatial fire behavior analyses are performed with an array of fire behavior modeling systems such as FARSITE, FlamMap, and the Large Fire Simulation System. These systems currently require standard or customized surface fire behavior fuel models as inputs that are often assigned through remote sensing information. The ability to handle hundreds or thousands of measured surface fuelbeds representing the fine scale variation in fire behavior on the landscape is constrained in terms of creating compatible custom fire behavior fuel models. In this study, we demonstrate an objective method for taking ecologically complex fuelbeds from inventory observations and converting those into a set of custom fuel models that can be mapped to the original landscape. We use an original set of 629 fuel inventory plots measured on an 80,000 ha contiguous landscape in the upper Atlantic Coastal Plain of the southeastern United States. From models linking stand conditions to component fuel loads, we impute fuelbeds for over 6000 stands. These imputed fuelbeds were then converted to fire behavior parameters under extreme fuel moisture and wind conditions (97th percentile) using the fuel characteristic classification system (FCCS) to estimate surface fire rate of spread, surface fire flame length, shrub layer reaction intensity (heat load), non-woody layer reaction intensity, woody layer reaction intensity, and litter-lichen-moss layer reaction intensity. We performed hierarchical cluster analysis of the stands based on the values of the fire behavior parameters. The resulting 7 clusters were the basis for the development of 7 custom fire behavior fuel models from the cluster centroids that were calibrated against the FCCS point data for wind and fuel moisture. The latter process resulted in calibration against flame length as it was difficult to obtain a simultaneous calibration against both rate of spread and flame length. The clusters based on FCCS fire behavior

Simulation of counter-current imbibition in water-wet fractured reservoirs based on discrete-fracture model

Directory of Open Access Journals (Sweden)

Wang Yueying

2017-08-01

Full Text Available Isolated fractures usually exist in fractured media systems, where the capillary pressure in the fracture is lower than that of the matrix, causing the discrepancy in oil recoveries between fractured and non-fractured porous media. Experiments, analytical solutions and conventional simulation methods based on the continuum model approach are incompetent or insufficient in describing media containing isolated fractures. In this paper, the simulation of the counter-current imbibition in fractured media is based on the discrete-fracture model (DFM. The interlocking or arrangement of matrix and fracture system within the model resembles the traditional discrete fracture network model and the hybrid-mixed-finite-element method is employed to solve the associated equations. The Behbahani experimental data validates our simulation solution for consistency. The simulation results of the fractured media show that the isolated-fractures affect the imbibition in the matrix block. Moreover, the isolated fracture parameters such as fracture length and fracture location influence the trend of the recovery curves. Thus, the counter-current imbibition behavior of media with isolated fractures can be predicted using this method based on the discrete-fracture model.

Summary of human social, cultural, behavioral (HSCB) modeling for information fusion panel discussion

Science.gov (United States)

Blasch, Erik; Salerno, John; Kadar, Ivan; Yang, Shanchieh J.; Fenstermacher, Laurie; Endsley, Mica; Grewe, Lynne

2013-05-01

During the SPIE 2012 conference, panelists convened to discuss "Real world issues and challenges in Human Social/Cultural/Behavioral modeling with Applications to Information Fusion." Each panelist presented their current trends and issues. The panel had agreement on advanced situation modeling, working with users for situation awareness and sense-making, and HSCB context modeling in focusing research activities. Each panelist added different perspectives based on the domain of interest such as physical, cyber, and social attacks from which estimates and projections can be forecasted. Also, additional techniques were addressed such as interest graphs, network modeling, and variable length Markov Models. This paper summarizes the panelists discussions to highlight the common themes and the related contrasting approaches to the domains in which HSCB applies to information fusion applications.

Performance of fire behavior fuel models developed for the Rothermel Surface Fire Spread Model

Science.gov (United States)

Robert Ziel; W. Matt Jolly

2009-01-01

In 2005, 40 new fire behavior fuel models were published for use with the Rothermel Surface Fire Spread Model. These new models are intended to augment the original 13 developed in 1972 and 1976. As a compiled set of quantitative fuel descriptions that serve as input to the Rothermel model, the selected fire behavior fuel model has always been critical to the resulting...

A modeling method for hybrid energy behaviors in flexible machining systems

International Nuclear Information System (INIS)

Li, Yufeng; He, Yan; Wang, Yan; Wang, Yulin; Yan, Ping; Lin, Shenlong

2015-01-01

Increasingly environmental and economic pressures have led to great concerns regarding the energy consumption of machining systems. Understanding energy behaviors of flexible machining systems is a prerequisite for improving energy efficiency of these systems. This paper proposes a modeling method to predict energy behaviors in flexible machining systems. The hybrid energy behaviors not only depend on the technical specification related of machine tools and workpieces, but are significantly affected by individual production scenarios. In the method, hybrid energy behaviors are decomposed into Structure-related energy behaviors, State-related energy behaviors, Process-related energy behaviors and Assignment-related energy behaviors. The modeling method for the hybrid energy behaviors is proposed based on Colored Timed Object-oriented Petri Net (CTOPN). The former two types of energy behaviors are modeled by constructing the structure of CTOPN, whist the latter two types of behaviors are simulated by applying colored tokens and associated attributes. Machining on two workpieces in the experimental workshop were undertaken to verify the proposed modeling method. The results showed that the method can provide multi-perspective transparency on energy consumption related to machine tools, workpieces as well as production management, and is particularly suitable for flexible manufacturing system when frequent changes in machining systems are often encountered. - Highlights: • Energy behaviors in flexible machining systems are modeled in this paper. • Hybrid characteristics of energy behaviors are examined from multiple viewpoints. • Flexible modeling method CTOPN is used to predict the hybrid energy behaviors. • This work offers a multi-perspective transparency on energy consumption

Adolescents' smoking behavior and its relationships with psychological constructs based on transtheoretical model: a cross-sectional survey.

Science.gov (United States)

Kim, Young-Ho

2006-05-01

Korean adolescents' smoking is currently being considered as a crucial factor determining the health status of adolescents and an important public health and social issue. The purpose of the study was to test the applicability of the Transtheoretical model to gain an understanding of smoking behavior change. A total of 706 adolescents who participated in the smoking cessation programs administered by the Korea Quit Smoking Association or Korean Association of Smoking & Health in 2003 were recruited. Four Korean-version questionnaires were used to identify the stages of smoking behavior and psychological attributes: Stage of Smoking Behavior Change Scale, Processes of Change Scale for Smoking, Decision Balance Scale for Smoking, and Self-efficacy Scale to avoid smoking. Korean adolescents' smoking behavior was differed according to gender. In addition, the findings revealed that behavioral and cognitive processes of change, self-efficacy, and positives differed across the stages of smoking behavior, and that psychological constructs of the transtheoretical model had a statistically significant impact on smoking behavior change. This research could spawn the development of theory-based and empirically supported smoking cessation intervention strategies and programs directed toward adolescents in the health care and nursing areas.

Modeling the behavioral substrates of associate learning and memory - Adaptive neural models

Science.gov (United States)

Lee, Chuen-Chien

1991-01-01

Three adaptive single-neuron models based on neural analogies of behavior modification episodes are proposed, which attempt to bridge the gap between psychology and neurophysiology. The proposed models capture the predictive nature of Pavlovian conditioning, which is essential to the theory of adaptive/learning systems. The models learn to anticipate the occurrence of a conditioned response before the presence of a reinforcing stimulus when training is complete. Furthermore, each model can find the most nonredundant and earliest predictor of reinforcement. The behavior of the models accounts for several aspects of basic animal learning phenomena in Pavlovian conditioning beyond previous related models. Computer simulations show how well the models fit empirical data from various animal learning paradigms.

Rasmussen's model of human behavior in laparoscopy training.

Science.gov (United States)

Wentink, M; Stassen, L P S; Alwayn, I; Hosman, R J A W; Stassen, H G

2003-08-01

Compared to aviation, where virtual reality (VR) training has been standardized and simulators have proven their benefits, the objectives, needs, and means of VR training in minimally invasive surgery (MIS) still have to be established. The aim of the study presented is to introduce Rasmussen's model of human behavior as a practical framework for the definition of the training objectives, needs, and means in MIS. Rasmussen distinguishes three levels of human behavior: skill-, rule-, and knowledge-based behaviour. The training needs of a laparoscopic novice can be determined by identifying the specific skill-, rule-, and knowledge-based behavior that is required for performing safe laparoscopy. Future objectives of VR laparoscopy trainers should address all three levels of behavior. Although most commercially available simulators for laparoscopy aim at training skill-based behavior, especially the training of knowledge-based behavior during complications in surgery will improve safety levels. However, the cost and complexity of a training means increases when the training objectives proceed from the training of skill-based behavior to the training of complex knowledge-based behavior. In aviation, human behavior models have been used successfully to integrate the training of skill-, rule-, and knowledge-based behavior in a full flight simulator. Understanding surgeon behavior is one of the first steps towards a future full-scale laparoscopy simulator.

Modeling Human Behavior to Anticipate Insider Attacks

Directory of Open Access Journals (Sweden)

Ryan E Hohimer

2011-01-01

Full Text Available The insider threat ranks among the most pressing cyber-security challenges that threaten government and industry information infrastructures. To date, no systematic methods have been developed that provide a complete and effective approach to prevent data leakage, espionage, and sabotage. Current practice is forensic in nature, relegating to the analyst the bulk of the responsibility to monitor, analyze, and correlate an overwhelming amount of data. We describe a predictive modeling framework that integrates a diverse set of data sources from the cyber domain, as well as inferred psychological/motivational factors that may underlie malicious insider exploits. This comprehensive threat assessment approach provides automated support for the detection of high-risk behavioral "triggers" to help focus the analyst's attention and inform the analysis. Designed to be domain-independent, the system may be applied to many different threat and warning analysis/sense-making problems.

Multiaxial behavior of foams - Experiments and modeling

Science.gov (United States)

Maheo, Laurent; Guérard, Sandra; Rio, Gérard; Donnard, Adrien; Viot, Philippe

2015-09-01

Cellular materials are strongly related to pressure level inside the material. It is therefore important to use experiments which can highlight (i) the pressure-volume behavior, (ii) the shear-shape behavior for different pressure level. Authors propose to use hydrostatic compressive, shear and combined pressure-shear tests to determine cellular materials behavior. Finite Element Modeling must take into account these behavior specificities. Authors chose to use a behavior law with a Hyperelastic, a Viscous and a Hysteretic contributions. Specific developments has been performed on the Hyperelastic one by separating the spherical and the deviatoric part to take into account volume change and shape change characteristics of cellular materials.

Superconducting current in a bisoliton superconductivity model

International Nuclear Information System (INIS)

Ermakov, V.N.; Kruchinin, S.P.; Ponezha, E.A.

1991-01-01

It is shown that the transition into a superconducting state with the current which is described by a bisoliton superconductivity model is accompanied by the deformation of the spectrum of one-particle states of the current carriers. The deformation value is proportional to the conducting current force. The residuaby resistance in such state is absent

Cognitive-Behavioral Grief Therapy: The ABC Model of Rational-Emotion Behavior Therapy

OpenAIRE

Malkinson, Ruth

2010-01-01

The article briefly reviews the changes that occurred in the field of grief and bereavement, viewing it as a process of searching for a "rational" meaning to life without the deceased in line with the concept of continuing bonds and thus replacing that of Fred’s concept of decathexis. Cognitive-behavioral therapy (CBT) evidenced-based studies for PTSD and complicated grief and the Cognitive-behavioral therapy − Rational-emotion behavior therapy (CBT-REBT) model for grief are reviewed. The foc...

Personality assessment and model comparison with behavioral data: A statistical framework and empirical demonstration with bonobos (Pan paniscus).

Science.gov (United States)

Martin, Jordan S; Suarez, Scott A

2017-08-01

Interest in quantifying consistent among-individual variation in primate behavior, also known as personality, has grown rapidly in recent decades. Although behavioral coding is the most frequently utilized method for assessing primate personality, limitations in current statistical practice prevent researchers' from utilizing the full potential of their coding datasets. These limitations include the use of extensive data aggregation, not modeling biologically relevant sources of individual variance during repeatability estimation, not partitioning between-individual (co)variance prior to modeling personality structure, the misuse of principal component analysis, and an over-reliance upon exploratory statistical techniques to compare personality models across populations, species, and data collection methods. In this paper, we propose a statistical framework for primate personality research designed to address these limitations. Our framework synthesizes recently developed mixed-effects modeling approaches for quantifying behavioral variation with an information-theoretic model selection paradigm for confirmatory personality research. After detailing a multi-step analytic procedure for personality assessment and model comparison, we employ this framework to evaluate seven models of personality structure in zoo-housed bonobos (Pan paniscus). We find that differences between sexes, ages, zoos, time of observation, and social group composition contributed to significant behavioral variance. Independently of these factors, however, personality nonetheless accounted for a moderate to high proportion of variance in average behavior across observational periods. A personality structure derived from past rating research receives the strongest support relative to our model set. This model suggests that personality variation across the measured behavioral traits is best described by two correlated but distinct dimensions reflecting individual differences in affiliation and

Interaction of mathematical modeling and social and behavioral HIV/AIDS research.

Science.gov (United States)

Cassels, Susan; Goodreau, Steven M

2011-03-01

HIV is transmitted within complex biobehavioral systems. Mathematical modeling can provide insight to complex population-level outcomes of various behaviors measured at an individual level. HIV models in the social and behavioral sciences can be categorized in a number of ways; here, we consider two classes of applications common in the field generally, and in the past year in particular: those models that explore significant behavioral determinants of HIV disparities within and between populations; and those models that seek to evaluate the potential impact of specific social and behavioral interventions. We discuss two overarching issues we see in the field: the need to further systematize effectiveness models of behavioral interventions, and the need for increasing investigation of the use of behavioral data in epidemic models. We believe that a recent initiative by the National Institutes of Health will qualitatively change the relationships between epidemic modeling and sociobehavioral prevention research in the coming years.

Organizational buying behavior: An integrated model

Directory of Open Access Journals (Sweden)

Rakić Beba

2002-01-01

Full Text Available Organizational buying behavior is decision making process by which formal organizations establish the need for purchased products and services, and identify, evaluate, and choose among alternative brands and suppliers. Understanding the buying decision processes is essential to developing the marketing programs of companies that sell to organizations, or to 'industrial customers'. In business (industrial marketing, exchange relationships between the organizational selling center and the organizational buying center are crucial. Integrative model of organizational buying behavior offers a systematic framework in analyzing the complementary factors and what effect they have on the behavior of those involved in making buying decisions.

Chaos in long-term behavior of some Bianchi-type VIII models

Energy Technology Data Exchange (ETDEWEB)

Halpern, P

1987-01-01

The long-term behavior of Bianchi-type VIII models with three different types of stress-energy tensors are examined and compared. The vacuum model, a matter-filled model, and a model with an electromagnetic field are considered. In each case the existence of chaotic behavior and transitions to chaotic behavior are discussed.

A judgment and decision-making model for plant behavior.

Science.gov (United States)

Karban, Richard; Orrock, John L

2018-06-12

Recently plant biologists have documented that plants, like animals, engage in many activities that can be considered as behaviors, although plant biologists currently lack a conceptual framework to understand these processes. Borrowing the well-established framework developed by psychologists, we propose that plant behaviors can be constructively modeled by identifying four distinct components: 1) a cue or stimulus that provides information, 2) a judgment whereby the plant perceives and processes this informative cue, 3) a decision whereby the plant chooses among several options based on their relative costs and benefits, and 4) action. Judgment for plants can be determined empirically by monitoring signaling associated with electrical, calcium, or hormonal fluxes. Decision-making can be evaluated empirically by monitoring gene expression or differential allocation of resources. We provide examples of the utility of this judgment and decision-making framework by considering cases in which plants either successfully or unsuccessfully induced resistance against attacking herbivores. Separating judgment from decision-making suggests new analytical paradigms (i.e., Bayesian methods for judgment and economic utility models for decision-making). Following this framework, we propose an experimental approach to plant behavior that explicitly manipulates the stimuli provided to plants, uses plants that vary in sensory abilities, and examines how environmental context affects plant responses. The concepts and approaches that follow from the judgment and decision-making framework can shape how we study and understand plant-herbivore interactions, biological invasions, plant responses to climate change, and the susceptibility of plants to evolutionary traps. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Geometry of behavioral spaces: A computational approach to analysis and understanding of agent based models and agent behaviors

Science.gov (United States)

Cenek, Martin; Dahl, Spencer K.

2016-11-01

Systems with non-linear dynamics frequently exhibit emergent system behavior, which is important to find and specify rigorously to understand the nature of the modeled phenomena. Through this analysis, it is possible to characterize phenomena such as how systems assemble or dissipate and what behaviors lead to specific final system configurations. Agent Based Modeling (ABM) is one of the modeling techniques used to study the interaction dynamics between a system's agents and its environment. Although the methodology of ABM construction is well understood and practiced, there are no computational, statistically rigorous, comprehensive tools to evaluate an ABM's execution. Often, a human has to observe an ABM's execution in order to analyze how the ABM functions, identify the emergent processes in the agent's behavior, or study a parameter's effect on the system-wide behavior. This paper introduces a new statistically based framework to automatically analyze agents' behavior, identify common system-wide patterns, and record the probability of agents changing their behavior from one pattern of behavior to another. We use network based techniques to analyze the landscape of common behaviors in an ABM's execution. Finally, we test the proposed framework with a series of experiments featuring increasingly emergent behavior. The proposed framework will allow computational comparison of ABM executions, exploration of a model's parameter configuration space, and identification of the behavioral building blocks in a model's dynamics.

Cognitive Models as Bridge between Brain and Behavior.

Science.gov (United States)

Love, Bradley C

2016-04-01

How can disparate neural and behavioral measures be integrated? Turner and colleagues propose joint modeling as a solution. Joint modeling mutually constrains the interpretation of brain and behavioral measures by exploiting their covariation structure. Simultaneous estimation allows for more accurate prediction than would be possible by considering these measures in isolation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Etiological model of disordered eating behaviors in Brazilian adolescent girls.

Science.gov (United States)

Fortes, Leonardo de Sousa; Filgueiras, Juliana Fernandes; Oliveira, Fernanda da Costa; Almeida, Sebastião Sousa; Ferreira, Maria Elisa Caputo

2016-01-01

The objective was to construct an etiological model of disordered eating behaviors in Brazilian adolescent girls. A total of 1,358 adolescent girls from four cities participated. The study used psychometric scales to assess disordered eating behaviors, body dissatisfaction, media pressure, self-esteem, mood, depressive symptoms, and perfectionism. Weight, height, and skinfolds were measured to calculate body mass index (BMI) and percent body fat (%F). Structural equation modeling explained 76% of variance in disordered eating behaviors (F(9, 1,351) = 74.50; p = 0.001). The findings indicate that body dissatisfaction mediated the relationship between media pressures, self-esteem, mood, BMI, %F, and disordered eating behaviors (F(9, 1,351) = 59.89; p = 0.001). Although depressive symptoms were not related to body dissatisfaction, the model indicated a direct relationship with disordered eating behaviors (F(2, 1,356) = 23.98; p = 0.001). In conclusion, only perfectionism failed to fit the etiological model of disordered eating behaviors in Brazilian adolescent girls.

An Ontology-Based Framework for Modeling User Behavior

DEFF Research Database (Denmark)

Razmerita, Liana

2011-01-01

and classifies its users according to their behavior. The user ontology is the backbone of OntobUMf and has been designed according to the Information Management System Learning Information Package (IMS LIP). The user ontology includes a Behavior concept that extends IMS LIP specification and defines...... characteristics of the users interacting with the system. Concrete examples of how OntobUMf is used in the context of a Knowledge Management (KM) System are provided. This paper discusses some of the implications of ontology-based user modeling for semantically enhanced KM and, in particular, for personal KM....... The results of this research may contribute to the development of other frameworks for modeling user behavior, other semantically enhanced user modeling frameworks, or other semantically enhanced information systems....

Multinucleon Ejection Model for Two Body Current Neutrino Interactions

Energy Technology Data Exchange (ETDEWEB)

Sobczyk, Jan T.; /Fermilab

2012-06-01

A model is proposed to describe nucleons ejected from a nucleus as a result of two-body-current neutrino interactions. The model can be easily implemented in Monte Carlo neutrino event generators. Various possibilities to measure the two-body-current contribution are discussed. The model can help identify genuine charge current quasielastic events and allow for a better determination of the systematic error on neutrino energy reconstruction in neutrino oscillation experiments.

Linking 3D spatial models of fuels and fire: Effects of spatial heterogeneity on fire behavior

Science.gov (United States)

Russell A. Parsons; William E. Mell; Peter McCauley

2011-01-01

Crownfire endangers fire fighters and can have severe ecological consequences. Prediction of fire behavior in tree crowns is essential to informed decisions in fire management. Current methods used in fire management do not address variability in crown fuels. New mechanistic physics-based fire models address convective heat transfer with computational fluid dynamics (...

Modeling Structural, Dyadic, and Individual Factors: The Inclusion and Exclusion Model of HIV Related Behavior

OpenAIRE

Albarracin, Dolores; Tannenbaum, Melanie B.; Glasman, Laura R.; Rothman, Alexander J.

2010-01-01

Changing HIV-related behaviors requires addressing the individual, dyadic, and structural influences that shape them. This supplement of AIDS & Behavior presents frameworks that integrate these three influences on behavior. Concepts from these frameworks were selected to model the processes by which structural factors affect individual HIV-related behavior. In the Inclusion/Exclusion Model, material and symbolic inclusions and exclusions (sharing versus denying resources) regulate individuals...

Emergent collective decision-making: Control, model and behavior

Science.gov (United States)

Shen, Tian

In this dissertation we study emergent collective decision-making in social groups with time-varying interactions and heterogeneously informed individuals. First we analyze a nonlinear dynamical systems model motivated by animal collective motion with heterogeneously informed subpopulations, to examine the role of uninformed individuals. We find through formal analysis that adding uninformed individuals in a group increases the likelihood of a collective decision. Secondly, we propose a model for human shared decision-making with continuous-time feedback and where individuals have little information about the true preferences of other group members. We study model equilibria using bifurcation analysis to understand how the model predicts decisions based on the critical threshold parameters that represent an individual's tradeoff between social and environmental influences. Thirdly, we analyze continuous-time data of pairs of human subjects performing an experimental shared tracking task using our second proposed model in order to understand transient behavior and the decision-making process. We fit the model to data and show that it reproduces a wide range of human behaviors surprisingly well, suggesting that the model may have captured the mechanisms of observed behaviors. Finally, we study human behavior from a game-theoretic perspective by modeling the aforementioned tracking task as a repeated game with incomplete information. We show that the majority of the players are able to converge to playing Nash equilibrium strategies. We then suggest with simulations that the mean field evolution of strategies in the population resemble replicator dynamics, indicating that the individual strategies may be myopic. Decisions form the basis of control and problems involving deciding collectively between alternatives are ubiquitous in nature and in engineering. Understanding how multi-agent systems make decisions among alternatives also provides insight for designing

Behavioral impairments in animal models for zinc deficiency

Directory of Open Access Journals (Sweden)

Simone eHagmeyer

2015-01-01

Full Text Available Apart from teratogenic and pathological effects of zinc deficiency such as the occurrence of skin lesions, anorexia, growth retardation, depressed wound healing, altered immune function, impaired night vision, and alterations in taste and smell acuity, characteristic behavioral changes in animal models and human patients suffering from zinc deficiency have been observed. Given that it is estimated that about 17% of the worldwide population are at risk for zinc deficiency and that zinc deficiency is associated with a variety of brain disorders and disease states in humans, it is of major interest to investigate, how these behavioral changes will affect the individual and a putative course of a disease. Thus, here, we provide a state of the art overview about the behavioral phenotypes observed in various models of zinc deficiency, among them environmentally produced zinc deficient animals as well as animal models based on a genetic alteration of a particular zinc homeostasis gene. Finally, we compare the behavioral phenotypes to the human condition of mild to severe zinc deficiency and provide a model, how zinc deficiency that is associated with many neurodegenerative and neuropsychological disorders might modify the disease pathologies.

Longitudinal Mediation Modeling of Unhealthy Behaviors as Mediators between Workplace Demands/Support and Depressive Symptoms

Science.gov (United States)

Magnusson Hanson, Linda L.; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo

2016-01-01

Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms. PMID:28036376

Longitudinal Mediation Modeling of Unhealthy Behaviors as Mediators between Workplace Demands/Support and Depressive Symptoms.

Science.gov (United States)

Magnusson Hanson, Linda L; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo

2016-01-01

Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms.

Behavior genetic modeling of human fertility

DEFF Research Database (Denmark)

Rodgers, J L; Kohler, H P; Kyvik, K O

2001-01-01

Behavior genetic designs and analysis can be used to address issues of central importance to demography. We use this methodology to document genetic influence on human fertility. Our data come from Danish twin pairs born from 1953 to 1959, measured on age at first attempt to get pregnant (First......Try) and number of children (NumCh). Behavior genetic models were fitted using structural equation modeling and DF analysis. A consistent medium-level additive genetic influence was found for NumCh, equal across genders; a stronger genetic influence was identified for FirstTry, greater for females than for males....... A bivariate analysis indicated significant shared genetic variance between NumCh and FirstTry....

Nanopore Current Oscillations: Nonlinear Dynamics on the Nanoscale.

Science.gov (United States)

Hyland, Brittany; Siwy, Zuzanna S; Martens, Craig C

2015-05-21

In this Letter, we describe theoretical modeling of an experimentally realized nanoscale system that exhibits the general universal behavior of a nonlinear dynamical system. In particular, we consider the description of voltage-induced current fluctuations through a single nanopore from the perspective of nonlinear dynamics. We briefly review the experimental system and its behavior observed and then present a simple phenomenological nonlinear model that reproduces the qualitative behavior of the experimental data. The model consists of a two-dimensional deterministic nonlinear bistable oscillator experiencing both dissipation and random noise. The multidimensionality of the model and the interplay between deterministic and stochastic forces are both required to obtain a qualitatively accurate description of the physical system.

Imposed currents in galvanic cells

NARCIS (Netherlands)

Biesheuvel, P.M.; Soestbergen, M.; Bazant, M.Z.

2009-01-01

We analyze the steady-state behavior of a general mathematical model for reversible galvanic cells, such as redox flow cells, reversible solid oxide fuel cells, and rechargeable batteries. We consider not only operation in the galvanic discharging mode, spontaneously generating a positive current

A BEHAVIORAL-APPROACH TO LINEAR EXACT MODELING

NARCIS (Netherlands)

ANTOULAS, AC; WILLEMS, JC

1993-01-01

The behavioral approach to system theory provides a parameter-free framework for the study of the general problem of linear exact modeling and recursive modeling. The main contribution of this paper is the solution of the (continuous-time) polynomial-exponential time series modeling problem. Both

Behavioral models as theoretical frames to analyze the business objective

Directory of Open Access Journals (Sweden)

Hernán Alonso Bafico

2015-12-01

Full Text Available This paper examines Pfeffer’s Models of Behavior and connects each of them with attributes of the definition of the firm’s objective, assumed as the maximization of the sustainable, long term valor of the residual claims.Each of the five models of behavior (rational, social, moral, retrospective and cognitive contributes to the decision making and goal setting processes with its particular and complementary elements. From those assuming complete rationality and frictionless markets, to the models emphasizing the role of ethical positions, and the presence of perceptive and cognitive mechanisms. The analysis highlights the main contributions of critical theories and models of behavior, underlining their focus on non-traditional variables, regarded as critical inputs for goal setting processes and designing alternative executive incentive schemes.  The explicit consideration of those variables does not indicate the need for a new definition of corporate objective. The maximization of the long term value of the shareholders’ claims still defines the relevant objective function of the firm, remaining as the main yardstick of corporate performance.Behavioral models are recognized as important tools to help managers direct their attention to long term strategies. In the last part, we comment on the relationship between the objective function and behavioral models, from the practitioners’ perspective.Key words: Firm Objectives, Behavioral Models, Value Maximization, Stakeholder Theory.

Modeling the spatial distribution of forest crown biomass and effects on fire behavior with FUEL3D and WFDS

Science.gov (United States)

Russell A. Parsons; William Mell; Peter McCauley

2010-01-01

Crown fire poses challenges to fire managers and can endanger fire fighters. Understanding of how fire interacts with tree crowns is essential to informed decisions about crown fire. Current operational crown fire predictions in the United States assume homogeneous crown fuels. While a new class of research fire models, which model fire behavior with computational...

Collective signaling behavior in a networked-oscillator model

Science.gov (United States)

Liu, Z.-H.; Hui, P. M.

2007-09-01

We propose and study the collective behavior of a model of networked signaling objects that incorporates several ingredients of real-life systems. These ingredients include spatial inhomogeneity with grouping of signaling objects, signal attenuation with distance, and delayed and impulsive coupling between non-identical signaling objects. Depending on the coupling strength and/or time-delay effect, the model exhibits completely, partially, and locally collective signaling behavior. In particular, a correlated signaling (CS) behavior is observed in which there exist time durations when nearly a constant fraction of oscillators in the system are in the signaling state. These time durations are much longer than the duration of a spike when a single oscillator signals, and they are separated by regular intervals in which nearly all oscillators are silent. Such CS behavior is similar to that observed in biological systems such as fireflies, cicadas, crickets, and frogs. The robustness of the CS behavior against noise is also studied. It is found that properly adjusting the coupling strength and noise level could enhance the correlated behavior.

Ecological models and pesticide risk assessment: current modeling practice.

Science.gov (United States)

Schmolke, Amelie; Thorbek, Pernille; Chapman, Peter; Grimm, Volker

2010-04-01

Ecological risk assessments of pesticides usually focus on risk at the level of individuals, and are carried out by comparing exposure and toxicological endpoints. However, in most cases the protection goal is populations rather than individuals. On the population level, effects of pesticides depend not only on exposure and toxicity, but also on factors such as life history characteristics, population structure, timing of application, presence of refuges in time and space, and landscape structure. Ecological models can integrate such factors and have the potential to become important tools for the prediction of population-level effects of exposure to pesticides, thus allowing extrapolations, for example, from laboratory to field. Indeed, a broad range of ecological models have been applied to chemical risk assessment in the scientific literature, but so far such models have only rarely been used to support regulatory risk assessments of pesticides. To better understand the reasons for this situation, the current modeling practice in this field was assessed in the present study. The scientific literature was searched for relevant models and assessed according to nine characteristics: model type, model complexity, toxicity measure, exposure pattern, other factors, taxonomic group, risk assessment endpoint, parameterization, and model evaluation. The present study found that, although most models were of a high scientific standard, many of them would need modification before they are suitable for regulatory risk assessments. The main shortcomings of currently available models in the context of regulatory pesticide risk assessments were identified. When ecological models are applied to regulatory risk assessments, we recommend reviewing these models according to the nine characteristics evaluated here. (c) 2010 SETAC.

Behavior Modeling -- Foundations and Applications

DEFF Research Database (Denmark)

This book constitutes revised selected papers from the six International Workshops on Behavior Modelling - Foundations and Applications, BM-FA, which took place annually between 2009 and 2014. The 9 papers presented in this volume were carefully reviewed and selected from a total of 58 papers...

Initial Smoking Experiences and Current Smoking Behaviors and Perceptions among Current Smokers

Directory of Open Access Journals (Sweden)

Hugh Klein

2013-01-01

Full Text Available Purpose. We examine early-onset cigarette smoking and how, if at all, it is related to subsequent smoking practices. Methods. From 2004 to 2007, face-to-face interviews were conducted with 485 adult cigarette smokers residing in the Atlanta metropolitan area. Data analysis involved a multivariate analysis to determine whether age of smoking onset was related to current smoking practices when the effects of gender, age, race, marital/relationship status, income, and educational attainment were taken into account. Results. The mean age for smoking onset was 14.8, and more than one-half of all smokers had their first cigarette between the ages of 12 and 16. Most people reported an interval of less than one month between their first and second time using tobacco. Earlier onset cigarette smoking was related to more cigarette use and worse tobacco-related health outcomes in adulthood. Conclusions. Early prevention and intervention are needed to avoid early-onset smoking behaviors. Intervening after initial experimentation but before patterned smoking practices are established will be challenging, as the interval between initial and subsequent use tends to be short.

Constitutive modeling of salt behavior: State of the technology

International Nuclear Information System (INIS)

Munson, D.E.; Wawersik, W.R.

1992-01-01

The modern investigation of the thermomechanical behavior of salt started in the mid-1930's and, for what appears to be a very narrow discipline, ''salt mechanics'' has acquired considerable technical depth and sophistication. The last three decades have been especially productive in constitutive model development and laboratory investigations of time-dependent creep behavior. This has been largely due ot anticipated use of domal or bedded salt deposits as sites for radioactive waste repositories and to expanded need for hydrocarbon and feedback storage caverns. Salt is an interesting material, in that it is ''metal-like''; and, therefore, constitutive modeling can draw upon a large body of metal deformation information to arrive at appropriate models of behavior. Testing apparatus and methods have centered on either uniaxial or triaxial compression to obtain steady state and transient creep responses. Flow and fracture potentials have been defined. Validation attempts of the models against field data, although limited, have proved promising. The objective here is to summarize the state-of-the-technology of the constitutive modeling of salt behavior or ''salt mechanics.''

Modelling the behavior of an oil saturated sand

International Nuclear Information System (INIS)

Evgin, E.; Altaee, A.; Lord, S.; Konuk, I.

1990-01-01

The experiments carried out in an earlier study show the oil contamination affects the strength and deformation characteristics of a crushed quartz sand. In the present study, a mathematical soil model is used to simulate the mechanical behavior of the same sand. The model parameters are determined for both clean and oil contaminated soil. Simulations are made for the stress-strain behavior of the soil in drained and undrained conventional traixial compression tests. In order to illustrate the effect of changes in the soil properties on the behavior of an engineering structure, a finite element analysis is carried out. In this paper comparative results are presented to show the differences in the behavior of a foundation resting on a clean sand, on an oil contaminated sand, and on a sand contaminated locally

A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding-gate MOSFETs

International Nuclear Information System (INIS)

Li Cong; Zhuang Yi-Qi; Zhang Li; Jin Gang

2014-01-01

A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding-gate (JLDMCSG) metal-oxide-semiconductor field-effect transistors (MOSFETs) is proposed. It is derived by solving the two-dimensional Poisson's equation in two continuous cylindrical regions with any simplifying assumption. Using this analytical model, the subthreshold characteristics of JLDMCSG MOSFETs are investigated in terms of channel electrostatic potential, horizontal electric field, and subthreshold current. Compared to junctionless single-material cylindrical surrounding-gate MOSFETs, JLDMCSG MOSFETs can effectively suppress short-channel effects and simultaneously improve carrier transport efficiency. It is found that the subthreshold current of JLDMCSG MOSFETs can be significantly reduced by adopting both a thin oxide and thin silicon channel. The accuracy of the analytical model is verified by its good agreement with the three-dimensional numerical simulator ISE TCAD

A two-dimensional finite element model of front surface current flow in cells under non-uniform, concentrated illumination

Energy Technology Data Exchange (ETDEWEB)

Mellor, A.; Domenech-Garret, J.L.; Chemisana, D.; Rosell, J.I. [Departament de Medi Ambient i C.S., University of Lleida, Av. Alcalde Rovira Roure 191, E25198 (Spain)

2009-09-15

A two-dimensional finite element model of current flow in the front surface of a PV cell is presented. In order to validate this model we perform an experimental test. Later, particular attention is paid to the effects of non-uniform illumination in the finger direction which is typical in a linear concentrator system. Fill factor, open circuit voltage and efficiency are shown to decrease with increasing degree of non-uniform illumination. It is shown that these detrimental effects can be mitigated significantly by reoptimization of the number of front surface metallization fingers to suit the degree of non-uniformity. The behavior of current flow in the front surface of a cell operating at open circuit voltage under non-uniform illumination is discussed in detail. (author)

Health behavior change: can genomics improve behavioral adherence?

Science.gov (United States)

McBride, Colleen M; Bryan, Angela D; Bray, Molly S; Swan, Gary E; Green, Eric D

2012-03-01

The National Human Genome Research Institute recommends pursuing "genomic information to improve behavior change interventions" as part of its strategic vision for genomics. The limited effectiveness of current behavior change strategies may be explained, in part, by their insensitivity to individual variation in adherence responses. The first step in evaluating whether genomics can inform customization of behavioral recommendations is evidence reviews to identify adherence macrophenotypes common across behaviors and individuals that have genetic underpinnings. Conceptual models of how biological, psychological, and environmental factors influence adherence also are needed. Researchers could routinely collect biospecimens and standardized adherence measurements of intervention participants to enable understanding of genetic and environmental influences on adherence, to guide intervention customization and prospective comparative effectiveness studies.

Modeling dynamic behavior of Radon-222 in the planetary boundary layer

International Nuclear Information System (INIS)

Yuan, Y.C.; Stunder, M.J.

1983-01-01

A model has been used to simulate the dynamic behavior of radon concentration in the lower atmosphere from naturally occurring sources. The model includes prediction of radon exhalation rate from the surface of the ground due to convection and diffusion processes and the radon concentration profile in the planetary boundary layer. A time-dependent radon exhalation rate, variable mixing height, and altitude-dependent diffusivity are incorporated into the diffusion model by transforming the governing equation. The Galerkin finite-element technique and Crank-Nicholson finite different time marching are used in solving the discretized differential equations. The model-simulated time-varying radon concentrations near the ground agree well with measurements made over a period of seven days. It has been demonstrated that the model provides a reasonably good prediction of ambient radon concentration. As a general tool, with the input of actual radon concentration measurements, the model is also capable of estimating average radon exhalation rate from the ground surface. With current techniques, radon flux measurement is still a time-consuming and difficult task

Understanding Eating Behaviors through Parental Communication and the Integrative Model of Behavioral Prediction.

Science.gov (United States)

Scheinfeld, Emily; Shim, Minsun

2017-05-01

Emerging adulthood (EA) is an important yet overlooked period for developing long-term health behaviors. During these years, emerging adults adopt health behaviors that persist throughout life. This study applies the Integrative Model of Behavioral Prediction (IMBP) to examine the role of childhood parental communication in predicting engagement in healthful eating during EA. Participants included 239 college students, ages 18 to 25, from a large university in the southern United States. Participants were recruited and data collection occurred spring 2012. Participants responded to measures to assess perceived parental communication, eating behaviors, attitudes, subjective norms, and behavioral control over healthful eating. SEM and mediation analyses were used to address the hypotheses posited. Data demonstrated that perceived parent-child communication - specifically, its quality and target-specific content - significantly predicted emerging adults' eating behaviors, mediated through subjective norm and perceived behavioral control. This study sets the stage for further exploration and understanding of different ways parental communication influences emerging adults' healthy behavior enactment.

Characterization of Elastic and Plastic Behaviors in Steel Plate Based on Eddy Current Technique Using a Portable Impedance Analyzer

Directory of Open Access Journals (Sweden)

Meng Fanlin

2017-01-01

Full Text Available A portable impedance analyzer (PIA was developed based on a TiePie-HS3 device to provide the comparable impedance measurement accuracy of the Agilent 4294a impedance analyzer in the frequency range of 0~250 kHz. Then the PIA was applied to monitor the tensile stress-induced variation of the eddy current sensor’s impedance in a medium-carbon steel sample. A model of equivalent magnetic field induced by the elastic stress and the number of pinning sites indicated that the inductance of the eddy current loop firstly increased with the increase in the tensile stress and then decreased at the yield point of the material. The experimental results testified that the variation of impedance amplitude, the variation of phase angle, and the shift of two featured frequencies demonstrated opposite variation trends before and after the yield point, as predicated by the model. A new parameter, which combined the impedance variation information of the selected two frequencies, was found to exhibit nearly monotonous dependency on the tensile stress in elastic and plastic stages. The new parameter together with the developed portable impedance analyzer provided the solution to identify the elastic and plastic behaviors in ferromagnetic materials in practical applications with an eddy current technique.

An Analysis of Organizational Behavior Management Research in Terms of the Three-Contingency Model of Performance Management

Science.gov (United States)

Weatherly, Nicholas L.; Malott, Richard W.

2008-01-01

The three-contingency model of performance management (Malott, 1992, 1993, 1999) was used to analyze interventions in the "Journal of Organizational Behavior Management (JOBM)" from the years 1990 through 2005 (Volume 11[1]-Volume 25[4]). The current article extends previous reviews (Malott, Shimamune, & Malott, 1992; Otto & Malott, 2004) by…

Fusing Visual and Behavioral Cues for Modeling User Experience in Games

DEFF Research Database (Denmark)

Shaker, Noor; Asteriadis, Stylianos; Yannakakis, Georgios N.

2013-01-01

Estimating affective and cognitive states in condi- tions of rich human-computer interaction, such as in games, is a field of growing academic and commercial interest. Entertain- ment and serious games can benefit from recent advances in the field as, having access to predictors of the current...... state of the player (or learner) can provide useful information for feeding adaptation mechanisms that aim to maximize engagement or learning effects. In this paper, we introduce a large data corpus derived from 58 participants that play the popular Super Mario Bros platform game and attempt to create...... accurate models of player experience for this game genre. Within the view of the current research, features extracted both from player gameplay behavior and game levels, and player visual characteristics have been utilized as potential indicators of reported affect expressed as pairwise preferences between...

An analytical gate tunneling current model for MOSFETs

Energy Technology Data Exchange (ETDEWEB)

Kazerouni, Iman Abaspur, E-mail: imanabaspur@gmail.com; Hosseini, Seyed Ebrahim [Sabzevar Tarbiat Moallem University, Electrical and Computer Department (Iran, Islamic Republic of)

2012-03-15

Gate tunneling current of MOSFETs is an important factor in modeling ultra small devices. In this paper, gate tunneling in present-generation MOSFETs is studied. In the proposed model, we calculate the electron wave function at the semiconductor-oxide interface and inversion charge by treating the inversion layer as a potential well, including some simplifying assumptions. Then we compute the gate tunneling current using the calculated wave function. The proposed model results have an excellent agreement with experimental results in the literature.

Error Resilient Video Compression Using Behavior Models

Directory of Open Access Journals (Sweden)

Jacco R. Taal

2004-03-01

Full Text Available Wireless and Internet video applications are inherently subjected to bit errors and packet errors, respectively. This is especially so if constraints on the end-to-end compression and transmission latencies are imposed. Therefore, it is necessary to develop methods to optimize the video compression parameters and the rate allocation of these applications that take into account residual channel bit errors. In this paper, we study the behavior of a predictive (interframe video encoder and model the encoders behavior using only the statistics of the original input data and of the underlying channel prone to bit errors. The resulting data-driven behavior models are then used to carry out group-of-pictures partitioning and to control the rate of the video encoder in such a way that the overall quality of the decoded video with compression and channel errors is optimized.

Modeling structural, dyadic, and individual factors: the inclusion and exclusion model of HIV related behavior.

Science.gov (United States)

Albarracin, Dolores; Tannenbaum, Melanie B; Glasman, Laura R; Rothman, Alexander J

2010-12-01

Changing HIV-related behaviors requires addressing the individual, dyadic, and structural influences that shape them. This supplement of AIDS & Behavior presents frameworks that integrate these three influences on behavior. Concepts from these frameworks were selected to model the processes by which structural factors affect individual HIV-related behavior. In the Inclusion/Exclusion Model, material and symbolic inclusions and exclusions (sharing versus denying resources) regulate individuals' ability and motivation to detect, prevent, and treat HIV. Structural interventions create inclusions that increase one's ability or motivation to perform these behaviors or exclusions that hinder one's ability or motivation to execute counterproductive behaviors. The need to expand research regarding multilevel influences on HIV-related behavior is also discussed, particularly concerning further understanding of sustained behavior change and effective dissemination of evidence-based intervention strategies.

A Language for Modeling Cultural Norms, Biases and Stereotypes for Human Behavior Models

National Research Council Canada - National Science Library

Solomon, Steven; van Lent, Michael; Core, Mark; Carpenter, Paul; Rosenberg, Milton

2008-01-01

.... The Culturally-Affected Behavior project seeks to define a language for encoding ethnographic data in order to capture cultural knowledge and use that knowledge to affect human behavior models...

MASCOTTE: analytical model of eddy current signals

International Nuclear Information System (INIS)

Delsarte, G.; Levy, R.

1992-01-01

Tube examination is a major application of the eddy current technique in the nuclear and petrochemical industries. Such examination configurations being specially adapted to analytical modes, a physical model is developed on portable computers. It includes simple approximations made possible by the effective conditions of the examinations. The eddy current signal is described by an analytical formulation that takes into account the tube dimensions, the sensor conception, the physical characteristics of the defect and the examination parameters. Moreover, the model makes it possible to associate real signals and simulated signals

Modeling and Cognitive Behavior: The Effects of Modeling, Modes of Modeling and Selected Model Attributes on Rule-Governed Language Behavior.

Science.gov (United States)

Grieshop, James Ivo

The effect of modeling on the performance of rule-governed language behaviors of 208 male and female, Anglo and Chicano, sixth grade students in Albuquerque, N.M. was experimentally investigated. Eight boys and 8 girls (4 each Chicano and Anglo) were randomly assigned to each of the 12 experimental conditions and to the control group. Three modes…

Shopping Behavior Recognition using a Language Modeling Analogy

NARCIS (Netherlands)

Popa, M.C.; Rothkrantz, L.J.M.; Wiggers, P.; Shan, C.

2012-01-01

Automatic understanding and recognition of human shopping behavior has many potential applications, attracting an increasing interest inthe market- ing domain. The reliability and performance of the automatic recognition system is highly in uenced by the adopted theoretical model of behavior. In

A Small Potassium Current in AgRP/NPY Neurons Regulates Feeding Behavior and Energy Metabolism.

Science.gov (United States)

He, Yanlin; Shu, Gang; Yang, Yongjie; Xu, Pingwen; Xia, Yan; Wang, Chunmei; Saito, Kenji; Hinton, Antentor; Yan, Xiaofeng; Liu, Chen; Wu, Qi; Tong, Qingchun; Xu, Yong

2016-11-08

Neurons that co-express agouti-related peptide (AgRP) and neuropeptide Y (NPY) are indispensable for normal feeding behavior. Firing activities of AgRP/NPY neurons are dynamically regulated by energy status and coordinate appropriate feeding behavior to meet nutritional demands. However, intrinsic mechanisms that regulate AgRP/NPY neural activities during the fed-to-fasted transition are not fully understood. We found that AgRP/NPY neurons in satiated mice express high levels of the small-conductance calcium-activated potassium channel 3 (SK3) and are inhibited by SK3-mediated potassium currents; on the other hand, food deprivation suppresses SK3 expression in AgRP/NPY neurons, and the decreased SK3-mediated currents contribute to fasting-induced activation of these neurons. Genetic mutation of SK3 specifically in AgRP/NPY neurons leads to increased sensitivity to diet-induced obesity, associated with chronic hyperphagia and decreased energy expenditure. Our results identify SK3 as a key intrinsic mediator that coordinates nutritional status with AgRP/NPY neural activities and animals' feeding behavior and energy metabolism. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Determinants of return behavior: a comparison of current and lapsed donors.

Science.gov (United States)

Germain, Marc; Glynn, Simone A; Schreiber, George B; Gélinas, Stéphanie; King, Melissa; Jones, Mike; Bethel, James; Tu, Yongling

2007-10-01

There is a need to identify factors explaining why some people stop donating blood. A random mail survey of first-time (FT) and repeat (RPT) current (donating within 6 months before survey) and lapsed (donating >2 years prior) donors was conducted. The self-administered questionnaire included questions on personal, social, and behavioral characteristics. Among 1280 current and 1672 lapsed donors with valid addresses, the participation rate was 66.8 and 39.2 percent, respectively. In FT donors, the odds of lapsing increased with education (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.34-3.55 for college or higher vs. Grade 12 or less education). Lapsed FT donors were more often asked to donate (OR, 1.89; 95% CI, 1.32-2.70) and had less interest in incentives (p marketing strategies that appeal solely to altruistic values need to be further evaluated for their effectiveness.

Human, Social, Cultural Behavior (HSCB) Modeling Workshop I: Characterizing the Capability Needs for HSCB Modeling

Science.gov (United States)

2008-07-01

The expectations correspond to different roles individuals perform SocialConstructionis Social constructionism is a school of thought Peter L...HUMAN, SOCIAL , CULTURAL BEHAVIOR (HSCB) MODELING WORKSHOP I: CHARACTERIZING THE CAPABILITY NEEDS FOR HSCB MODELING FINAL REPORT... Social , Cultural Behavior (HSCB) Modeling Workshop I: Characterizing the Capability Needs for HSCB Modeling 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

Micromechanical modeling of rate-dependent behavior of Connective tissues.

Science.gov (United States)

Fallah, A; Ahmadian, M T; Firozbakhsh, K; Aghdam, M M

2017-03-07

In this paper, a constitutive and micromechanical model for prediction of rate-dependent behavior of connective tissues (CTs) is presented. Connective tissues are considered as nonlinear viscoelastic material. The rate-dependent behavior of CTs is incorporated into model using the well-known quasi-linear viscoelasticity (QLV) theory. A planar wavy representative volume element (RVE) is considered based on the tissue microstructure histological evidences. The presented model parameters are identified based on the available experiments in the literature. The presented constitutive model introduced to ABAQUS by means of UMAT subroutine. Results show that, monotonic uniaxial test predictions of the presented model at different strain rates for rat tail tendon (RTT) and human patellar tendon (HPT) are in good agreement with experimental data. Results of incremental stress-relaxation test are also presented to investigate both instantaneous and viscoelastic behavior of connective tissues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Complex systems and health behavior change: insights from cognitive science.

Science.gov (United States)

Orr, Mark G; Plaut, David C

2014-05-01

To provide proof-of-concept that quantum health behavior can be instantiated as a computational model that is informed by cognitive science, the Theory of Reasoned Action, and quantum health behavior theory. We conducted a synthetic review of the intersection of quantum health behavior change and cognitive science. We conducted simulations, using a computational model of quantum health behavior (a constraint satisfaction artificial neural network) and tested whether the model exhibited quantum-like behavior. The model exhibited clear signs of quantum-like behavior. Quantum health behavior can be conceptualized as constraint satisfaction: a mitigation between current behavioral state and the social contexts in which it operates. We outlined implications for moving forward with computational models of both quantum health behavior and health behavior in general.

Cathode fall model and current-voltage characteristics of field emission driven direct current microplasmas

Energy Technology Data Exchange (ETDEWEB)

Venkattraman, Ayyaswamy [Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai 600036 (India)

2013-11-15

The post-breakdown characteristics of field emission driven microplasma are studied theoretically and numerically. A cathode fall model assuming a linearly varying electric field is used to obtain equations governing the operation of steady state field emission driven microplasmas. The results obtained from the model by solving these equations are compared with particle-in-cell with Monte Carlo collisions simulation results for parameters including the plasma potential, cathode fall thickness, ion number density in the cathode fall, and current density vs voltage curves. The model shows good overall agreement with the simulations but results in slightly overpredicted values for the plasma potential and the cathode fall thickness attributed to the assumed electric field profile. The current density vs voltage curves obtained show an arc region characterized by negative slope as well as an abnormal glow discharge characterized by a positive slope in gaps as small as 10 μm operating at atmospheric pressure. The model also retrieves the traditional macroscale current vs voltage theory in the absence of field emission.

Cathode fall model and current-voltage characteristics of field emission driven direct current microplasmas

International Nuclear Information System (INIS)

Venkattraman, Ayyaswamy

2013-01-01

The post-breakdown characteristics of field emission driven microplasma are studied theoretically and numerically. A cathode fall model assuming a linearly varying electric field is used to obtain equations governing the operation of steady state field emission driven microplasmas. The results obtained from the model by solving these equations are compared with particle-in-cell with Monte Carlo collisions simulation results for parameters including the plasma potential, cathode fall thickness, ion number density in the cathode fall, and current density vs voltage curves. The model shows good overall agreement with the simulations but results in slightly overpredicted values for the plasma potential and the cathode fall thickness attributed to the assumed electric field profile. The current density vs voltage curves obtained show an arc region characterized by negative slope as well as an abnormal glow discharge characterized by a positive slope in gaps as small as 10 μm operating at atmospheric pressure. The model also retrieves the traditional macroscale current vs voltage theory in the absence of field emission

Markov chain modeling of policyholder behavior in life insurance and pension

DEFF Research Database (Denmark)

Henriksen, Lars Frederik Brandt; Nielsen, Jeppe Woetmann; Steffensen, Mogens

2014-01-01

We calculate reserves regarding expected policyholder behavior. The behavior is modeled to occur incidentally similarly to insurance risk. The focus is on multi-state modelling of insurance risk and behavioral risk in terms of free policy risk and surrender risk. We discuss valuation techniques i...

Cardiac magnetic source imaging based on current multipole model

International Nuclear Information System (INIS)

Tang Fa-Kuan; Wang Qian; Hua Ning; Lu Hong; Tang Xue-Zheng; Ma Ping

2011-01-01

It is widely accepted that the heart current source can be reduced into a current multipole. By adopting three linear inverse methods, the cardiac magnetic imaging is achieved in this article based on the current multipole model expanded to the first order terms. This magnetic imaging is realized in a reconstruction plane in the centre of human heart, where the current dipole array is employed to represent realistic cardiac current distribution. The current multipole as testing source generates magnetic fields in the measuring plane, serving as inputs of cardiac magnetic inverse problem. In the heart-torso model constructed by boundary element method, the current multipole magnetic field distribution is compared with that in the homogeneous infinite space, and also with the single current dipole magnetic field distribution. Then the minimum-norm least-squares (MNLS) method, the optimal weighted pseudoinverse method (OWPIM), and the optimal constrained linear inverse method (OCLIM) are selected as the algorithms for inverse computation based on current multipole model innovatively, and the imaging effects of these three inverse methods are compared. Besides, two reconstructing parameters, residual and mean residual, are also discussed, and their trends under MNLS, OWPIM and OCLIM each as a function of SNR are obtained and compared. (general)

Adaptive Maneuvering Frequency Method of Current Statistical Model

Institute of Scientific and Technical Information of China (English)

Wei Sun; Yongjian Yang

2017-01-01

Current statistical model(CSM) has a good performance in maneuvering target tracking. However, the fixed maneuvering frequency will deteriorate the tracking results, such as a serious dynamic delay, a slowly converging speedy and a limited precision when using Kalman filter(KF) algorithm. In this study, a new current statistical model and a new Kalman filter are proposed to improve the performance of maneuvering target tracking. The new model which employs innovation dominated subjection function to adaptively adjust maneuvering frequency has a better performance in step maneuvering target tracking, while a fluctuant phenomenon appears. As far as this problem is concerned, a new adaptive fading Kalman filter is proposed as well. In the new Kalman filter, the prediction values are amended in time by setting judgment and amendment rules,so that tracking precision and fluctuant phenomenon of the new current statistical model are improved. The results of simulation indicate the effectiveness of the new algorithm and the practical guiding significance.

Economics as a factor in models of behavioral motivation and change.

Science.gov (United States)

Montoya, I D; Atkinson, J S; Trevino, R A

2000-02-01

This note first presents a summary of four main behavioral models that are used to explain behavioral motivation and change. Three models are based on psychosocial theory. They are: 1) the Theory of Reasoned Action, 2) the Theory of Planned Behavior, and 3) the Theory of Stages-of-Change. The fourth model is based on economic theory and is known as the Rational Addiction Model. Each model is analyzed for its strengths and weaknesses. The note concludes by arguing for the usefulness of integrating the economic and the psychosocial models to study drug use. Specific examples and suggestions are presented.

Calculating electron cyclotron current drive stabilization of resistive tearing modes in a nonlinear magnetohydrodynamic model

International Nuclear Information System (INIS)

Jenkins, Thomas G.; Schnack, Dalton D.; Kruger, Scott E.; Hegna, C. C.; Sovinec, Carl R.

2010-01-01

A model which incorporates the effects of electron cyclotron current drive (ECCD) into the magnetohydrodynamic equations is implemented in the NIMROD code [C. R. Sovinec et al., J. Comput. Phys. 195, 355 (2004)] and used to investigate the effect of ECCD injection on the stability, growth, and dynamical behavior of magnetic islands associated with resistive tearing modes. In addition to qualitatively and quantitatively agreeing with numerical results obtained from the inclusion of localized ECCD deposition in static equilibrium solvers [A. Pletzer and F. W. Perkins, Phys. Plasmas 6, 1589 (1999)], predictions from the model further elaborate the role which rational surface motion plays in these results. The complete suppression of the (2,1) resistive tearing mode by ECCD is demonstrated and the relevant stabilization mechanism is determined. Consequences of the shifting of the mode rational surface in response to the injected current are explored, and the characteristic short-time responses of resistive tearing modes to spatial ECCD alignments which are stabilizing are also noted. We discuss the relevance of this work to the development of more comprehensive predictive models for ECCD-based mitigation and control of neoclassical tearing modes.

Spontaneous behavioral responses in the orofacial region: A model of trigeminal pain in mouse

Science.gov (United States)

Romero-Reyes, Marcela; Akerman, Simon; Nguyen, Elaine; Vijjeswarapu, Alice; Hom, Betty; Dong, Hong-Wei; Charles, Andrew C.

2012-01-01

OBJECTIVES To develop a translational mouse model for the study and measurement of non-evoked pain in the orofacial region by establishing markers of nociceptive-specific grooming behaviors in the mouse. BACKGROUND Some of the most prevalent and debilitating conditions involve pain in the trigeminal distribution. Although there are current therapies for these pain conditions, for many patients they are far from optimal. Understanding the pathophysiology of pain disorders arising from structures innervated by the trigeminal nerve is still limited and most animal behavioral models focus on the measurement of evoked pain. In patients, spontaneous (non-evoked) pain responses provide a more accurate representation of the pain experience than do responses that are evoked by an artificial stimulus. Therefore, the development of animal models that measure spontaneous nociceptive behaviors may provide a significant translational tool for a better understanding of pain neurobiology. METHODS C57BL/6 mice received either an injection of 0.9% Saline solution or complete Freund’s adjuvant (CFA) into the right masseter muscle. Animals were video recorded and then analyzed by an observer blind to the experiment group. The duration of different facial grooming patterns performed in the area of injection were measured. After 2 hrs, mice were euthanized, perfused and the brainstem was removed. Fos protein expression in the trigeminal nucleus caudalis was quantified using immunohistochemistry to investigate nociceptive-specific neuronal activation. A separate group of animals was treated with morphine sulfate, to determine the nociceptive-specific nature of their behaviors. RESULTS We characterized and quantified 3 distinct patterns of acute grooming behaviors: fore-paw rubbing, lower lip skin/cheek rubbing against enclosure floor and hind paw scratching. These behaviors occurred with a reproducible frequency and time course, and were inhibited by the analgesic morphine. CFA

Integration of Theory of Planned Behavior and Norm Activation Model on Student Behavior Model Using Cars for Traveling to Campus

Directory of Open Access Journals (Sweden)

Setiawan, R.

2014-01-01

Full Text Available Although there are clear environmental, economic, and social drawbacks in using private vehicles, students still choose cars to get to campus. This study reports an investigation of psychological factors influencing this behavior from the perspective of the Theory of Planned Behavior and Norm Activation Model. Students from three different university campuses in Surabaya, Indonesia, (n = 312 completed a survey on their car commuting behavior. Results indicated that perceived behavioral control and personal norm were the strongest factors that influence behavioral intention. Attitude, subjective norm, perceived behavioral control, and personal norm explain 62.7% variance of the behavioral intention. In turn, behavioral intention explains 42.5% of the variance of the actual car use. Implications of these findings are that in order to alter the use of car, university should implement both structural and psychological interventions. Effective interventions should be designed to raise the awareness of negative aspects of car use.

Surface CUrrents from a Diagnostic model (SCUD): Pacific

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The SCUD data product is an estimate of upper-ocean velocities computed from a diagnostic model (Surface CUrrents from a Diagnostic model). This model makes daily...

Individualized model predicts brain current flow during transcranial direct-current stimulation treatment in responsive stroke patient.

Science.gov (United States)

Datta, Abhishek; Baker, Julie M; Bikson, Marom; Fridriksson, Julius

2011-07-01

Although numerous published reports have demonstrated the beneficial effects of transcranial direct-current stimulation (tDCS) on task performance, fundamental questions remain regarding the optimal electrode configuration on the scalp. Moreover, it is expected that lesioned brain tissue will influence current flow and should therefore be considered (and perhaps leveraged) in the design of individualized tDCS therapies for stroke. The current report demonstrates how different electrode configurations influence the flow of electrical current through brain tissue in a patient who responded positively to a tDCS treatment targeting aphasia. The patient, a 60-year-old man, sustained a left hemisphere ischemic stroke (lesion size = 87.42 mL) 64 months before his participation. In this study, we present results from the first high-resolution (1 mm(3)) model of tDCS in a brain with considerable stroke-related damage; the model was individualized for the patient who received anodal tDCS to his left frontal cortex with the reference cathode electrode placed on his right shoulder. We modeled the resulting brain current flow and also considered three additional reference electrode positions: right mastoid, right orbitofrontal cortex, and a "mirror" configuration with the anode over the undamaged right cortex. Our results demonstrate the profound effect of lesioned tissue on resulting current flow and the ability to modulate current pattern through the brain, including perilesional regions, through electrode montage design. The complexity of brain current flow modulation by detailed normal and pathologic anatomy suggest: (1) That computational models are critical for the rational interpretation and design of individualized tDCS stroke-therapy; and (2) These models must accurately reproduce head anatomy as shown here. Copyright © 2011 Elsevier Inc. All rights reserved.

Is Sexual Behavior Healthy for Adolescents? A Conceptual Framework for Research on Adolescent Sexual Behavior and Physical, Mental, and Social Health

Science.gov (United States)

Vasilenko, Sara A.; Lefkowitz, Eva S.; Welsh, Deborah P.

2014-01-01

Although research has increasingly emphasized how adolescent sexual behavior may be associated with aspects of health beyond unwanted pregnancy and sexually transmitted infections, no current theoretical or conceptual model fully explains associations between sexual behavior and multiple facets of health. We provide a conceptual model that…

Health behavior change in advance care planning: an agent-based model

Directory of Open Access Journals (Sweden)

Natalie C. Ernecoff

2016-02-01

Full Text Available Abstract Background A practical and ethical challenge in advance care planning research is controlling and intervening on human behavior. Additionally, observing dynamic changes in advance care planning (ACP behavior proves difficult, though tracking changes over time is important for intervention development. Agent-based modeling (ABM allows researchers to integrate complex behavioral data about advance care planning behaviors and thought processes into a controlled environment that is more easily alterable and observable. Literature to date has not addressed how best to motivate individuals, increase facilitators and reduce barriers associated with ACP. We aimed to build an ABM that applies the Transtheoretical Model of behavior change to ACP as a health behavior and accurately reflects: 1 the rates at which individuals complete the process, 2 how individuals respond to barriers, facilitators, and behavioral variables, and 3 the interactions between these variables. Methods We developed a dynamic ABM of the ACP decision making process based on the stages of change posited by the Transtheoretical Model. We integrated barriers, facilitators, and other behavioral variables that agents encounter as they move through the process. Results We successfully incorporated ACP barriers, facilitators, and other behavioral variables into our ABM, forming a plausible representation of ACP behavior and decision-making. The resulting distributions across the stages of change replicated those found in the literature, with approximately half of participants in the action-maintenance stage in both the model and the literature. Conclusions Our ABM is a useful method for representing dynamic social and experiential influences on the ACP decision making process. This model suggests structural interventions, e.g. increasing access to ACP materials in primary care clinics, in addition to improved methods of data collection for behavioral studies, e.g. incorporating

Health behavior change in advance care planning: an agent-based model.

Science.gov (United States)

Ernecoff, Natalie C; Keane, Christopher R; Albert, Steven M

2016-02-29

A practical and ethical challenge in advance care planning research is controlling and intervening on human behavior. Additionally, observing dynamic changes in advance care planning (ACP) behavior proves difficult, though tracking changes over time is important for intervention development. Agent-based modeling (ABM) allows researchers to integrate complex behavioral data about advance care planning behaviors and thought processes into a controlled environment that is more easily alterable and observable. Literature to date has not addressed how best to motivate individuals, increase facilitators and reduce barriers associated with ACP. We aimed to build an ABM that applies the Transtheoretical Model of behavior change to ACP as a health behavior and accurately reflects: 1) the rates at which individuals complete the process, 2) how individuals respond to barriers, facilitators, and behavioral variables, and 3) the interactions between these variables. We developed a dynamic ABM of the ACP decision making process based on the stages of change posited by the Transtheoretical Model. We integrated barriers, facilitators, and other behavioral variables that agents encounter as they move through the process. We successfully incorporated ACP barriers, facilitators, and other behavioral variables into our ABM, forming a plausible representation of ACP behavior and decision-making. The resulting distributions across the stages of change replicated those found in the literature, with approximately half of participants in the action-maintenance stage in both the model and the literature. Our ABM is a useful method for representing dynamic social and experiential influences on the ACP decision making process. This model suggests structural interventions, e.g. increasing access to ACP materials in primary care clinics, in addition to improved methods of data collection for behavioral studies, e.g. incorporating longitudinal data to capture behavioral dynamics.

Model analysis of adaptive car driving behavior

NARCIS (Netherlands)

Wewerinke, P.H.

1996-01-01

This paper deals with two modeling approaches to car driving. The first one is a system theoretic approach to describe adaptive human driving behavior. The second approach utilizes neural networks. As an illustrative example the overtaking task is considered and modeled in system theoretic terms.

Predicting Oral Health Behavior using the Health Promotion Model among School Students: a Cross-sectional Survey

Directory of Open Access Journals (Sweden)

Abdurrahman Charkazi

2016-07-01

Full Text Available teeth and T=permanent teeth has been increasing from 1957 to 2015 years in Iran. The current survey aimed to test the power of health promotion model for predicting the oral health behavior among high-school students.  Materials and Methods: A cross-sectional study was conducted on 482 high school students in Gorgan city, Iran. Multi-cluster sampling was used to recruit the samples. A researcher-made questionnaire based on HPM was implemented to collect data. To analyze, SPSS-18 and statistical tests, including t-test, Pearson correlation coefficient and univariate and multivariate regression models were used. Results: A total of 482 high-school students including 255 (52.9% male and 227 (47.1% with mean age of 16.02 ± 0.5 were investigated. The highest and lowest prevalent positive oral health behavior were tooth brushing (73% and using fluidized oral irrigator (3.6%, respectively. Except for perceived barriers (with negative correlation, all constructs of HBM were positively related to oral health behaviors. Self-efficacy was the strongest predictor of oral health behavior (β=0.653 (r=0.541, P

Modeling the Impact of Motivation, Personality, and Emotion on Social Behavior

Science.gov (United States)

Miller, Lynn C.; Read, Stephen J.; Zachary, Wayne; Rosoff, Andrew

Models seeking to predict human social behavior must contend with multiple sources of individual and group variability that underlie social behavior. One set of interrelated factors that strongly contribute to that variability - motivations, personality, and emotions - has been only minimally incorporated in previous computational models of social behavior. The Personality, Affect, Culture (PAC) framework is a theory-based computational model that addresses this gap. PAC is used to simulate social agents whose social behavior varies according to their personalities and emotions, which, in turn, vary according to their motivations and underlying motive control parameters. Examples involving disease spread and counter-insurgency operations show how PAC can be used to study behavioral variability in different social contexts.

A New Perspective on the Foraging Ecology of Apex Predators in the California Current: Results from a Fully Coupled Ecosystem Model

Science.gov (United States)

Fiechter, J.; Huckstadt, L. A.; Rose, K.; Costa, D. P.; Curchitser, E. N.; Hedstrom, K.; Edwards, C. A.; Moore, A. M.

2016-02-01

Results from a fully coupled end-to-end ecosystem model for the California Current Large Marine Ecosystem are used to describe the impact of environmental variability on the foraging ecology of its most abundant apex predator, California sea lions (Zalophus californianus). The ecosystem model consists of a biogeochemical submodel embedded in a regional ocean circulation submodel, and both coupled with a multi-species individual-based submodel for forage fish (sardine and anchovy) and California sea lions. For sea lions, bioenergetics and behavioral attributes are specified using available TOPP (Tagging Of Pacific Predators) data on their foraging patterns and diet in the California Current. Sardine and anchovy are explicitly included in the model as they represent important prey sources for California sea lions and exhibit significant interannual and decadal variability in population abundances. Output from a 20-year run (1989-2008) of the model demonstrates how different physical and biological processes control habitat utilization and foraging success of California sea lions on interannual time scales. A principal component analysis of sea lion foraging patterns indicates that the first mode of variability is alongshore and tied to sardine availability, while the second mode is cross-shore and associated with coastal upwelling intensity (a behavior consistent with male sea lion tracking data collected in 2004 vs. 2005). The results also illustrate how variability in environmental conditions and forage fish distribution affects sea lions feeding success. While specifically focusing on the foraging ecology of sea lions, our modeling framework has the ability to provide new and unique perspectives on trophic interactions in the California Current, or other regions where similar end-to-end ecosystem models may be implemented.

Bifurcation Behavior Analysis in a Predator-Prey Model

Directory of Open Access Journals (Sweden)

Nan Wang

2016-01-01

Full Text Available A predator-prey model is studied mathematically and numerically. The aim is to explore how some key factors influence dynamic evolutionary mechanism of steady conversion and bifurcation behavior in predator-prey model. The theoretical works have been pursuing the investigation of the existence and stability of the equilibria, as well as the occurrence of bifurcation behaviors (transcritical bifurcation, saddle-node bifurcation, and Hopf bifurcation, which can deduce a standard parameter controlled relationship and in turn provide a theoretical basis for the numerical simulation. Numerical analysis ensures reliability of the theoretical results and illustrates that three stable equilibria will arise simultaneously in the model. It testifies the existence of Bogdanov-Takens bifurcation, too. It should also be stressed that the dynamic evolutionary mechanism of steady conversion and bifurcation behavior mainly depend on a specific key parameter. In a word, all these results are expected to be of use in the study of the dynamic complexity of ecosystems.

Chaotic behavior in a hydrodynamic model of a fluidized bed reactor

International Nuclear Information System (INIS)

Schouten, J.C.; van den Bleek, C.M.

1991-01-01

Recent preliminary experimental studies using time-series analysis have demonstrated that the multi-phase flow in fluidized bed reactors can be characterized as chaotic. In the present paper, it is therefore argued that the chaotic time-dependence of fluidization is a characteristic feature which should be included in scaling rules for fluidized bed reactors. For example, the similarity groups applied in dimensionless fluidized bed scaling should be improved by extending them with functions of the relevant numbers from chaos theory, such as the correlation and embedding dimension or the maximum Lyapunov exponent. This requires that the dependence of these numbers on fluidization parameters must be theoretically and experimentally investigated. The concept of chaos in fluidization also requires that the classical, empirically developed, hydrodynamic models that are applied in fluidized bed scaling are amended to include time-dependence, non-linearity as well as a sufficient level of complexity before they can predict any chaotic behavior. An example is given of chaotic behavior generated in the classical counter-current flow model according to Van Deemter by writing the upwards solids velocity as a harmonic oscillating function of time. A low-dimensional strange attractor is found, embedded in two-dimensional phase space, of which the correlation dimension depends on the solids exchange coefficient

On single and double soft behaviors in NLSM

International Nuclear Information System (INIS)

Du, Yi-Jian; Luo, Hui

2015-01-01

In this paper, we study the single and double soft behaviors of tree level off-shell currents and on-shell amplitudes in nonlinear sigma model (NLSM). We first propose and prove the leading soft behavior of the tree level currents with a single soft particle. In the on-shell limit, this single soft emission becomes the Adler’s zero. Then we establish the leading and subleading soft behaviors of tree level currents with two adjacent soft particles. With a careful analysis of the on-shell limit, we obtain the double soft behaviors of on-shell amplitudes where the two soft particles are adjacent to each other. By applying Kleiss-Kuijf (KK) relation, we further obtain the leading and subleading behaviors of amplitudes with two nonadjacent soft particles.

Animal models of binge drinking, current challenges to improve face validity.

Science.gov (United States)

Jeanblanc, Jérôme; Rolland, Benjamin; Gierski, Fabien; Martinetti, Margaret P; Naassila, Mickael

2018-05-05

Binge drinking (BD), i.e., consuming a large amount of alcohol in a short period of time, is an increasing public health issue. Though no clear definition has been adopted worldwide the speed of drinking seems to be a keystone of this behavior. Developing relevant animal models of BD is a priority for gaining a better characterization of the neurobiological and psychobiological mechanisms underlying this dangerous and harmful behavior. Until recently, preclinical research on BD has been conducted mostly using forced administration of alcohol, but more recent studies used scheduled access to alcohol, to model more voluntary excessive intakes, and to achieve signs of intoxications that mimic the human behavior. The main challenges for future research are discussed regarding the need of good face validity, construct validity and predictive validity of animal models of BD. Copyright © 2018 Elsevier Ltd. All rights reserved.

Lattice model for influenza spreading with spontaneous behavioral changes.

Science.gov (United States)

Fierro, Annalisa; Liccardo, Antonella

2013-01-01

Individual behavioral response to the spreading of an epidemic plays a crucial role in the progression of the epidemic itself. The risk perception induces individuals to adopt a protective behavior, as for instance reducing their social contacts, adopting more restrictive hygienic measures or undergoing prophylaxis procedures. In this paper, starting with a previously developed lattice-gas SIR model, we construct a coupled behavior-disease model for influenza spreading with spontaneous behavioral changes. The focus is on self-initiated behavioral changes that alter the susceptibility to the disease, without altering the contact patterns among individuals. Three different mechanisms of awareness spreading are analyzed: the local spreading due to the presence in the neighborhood of infective individuals; the global spreading due to the news published by the mass media and to educational campaigns implemented at institutional level; the local spreading occurring through the "thought contagion" among aware and unaware individuals. The peculiarity of the present approach is that the awareness spreading model is calibrated on available data on awareness and concern of the population about the risk of contagion. In particular, the model is validated against the A(H1N1) epidemic outbreak in Italy during the 2009/2010 season, by making use of the awareness data gathered by the behavioral risk factor surveillance system (PASSI). We find that, increasing the accordance between the simulated awareness spreading and the PASSI data on risk perception, the agreement between simulated and experimental epidemiological data improves as well. Furthermore, we show that, within our model, the primary mechanism to reproduce a realistic evolution of the awareness during an epidemic, is the one due to globally available information. This result highlights how crucial is the role of mass media and educational campaigns in influencing the epidemic spreading of infectious diseases.

Lattice model for influenza spreading with spontaneous behavioral changes.

Directory of Open Access Journals (Sweden)

Annalisa Fierro

Full Text Available Individual behavioral response to the spreading of an epidemic plays a crucial role in the progression of the epidemic itself. The risk perception induces individuals to adopt a protective behavior, as for instance reducing their social contacts, adopting more restrictive hygienic measures or undergoing prophylaxis procedures. In this paper, starting with a previously developed lattice-gas SIR model, we construct a coupled behavior-disease model for influenza spreading with spontaneous behavioral changes. The focus is on self-initiated behavioral changes that alter the susceptibility to the disease, without altering the contact patterns among individuals. Three different mechanisms of awareness spreading are analyzed: the local spreading due to the presence in the neighborhood of infective individuals; the global spreading due to the news published by the mass media and to educational campaigns implemented at institutional level; the local spreading occurring through the "thought contagion" among aware and unaware individuals. The peculiarity of the present approach is that the awareness spreading model is calibrated on available data on awareness and concern of the population about the risk of contagion. In particular, the model is validated against the A(H1N1 epidemic outbreak in Italy during the 2009/2010 season, by making use of the awareness data gathered by the behavioral risk factor surveillance system (PASSI. We find that, increasing the accordance between the simulated awareness spreading and the PASSI data on risk perception, the agreement between simulated and experimental epidemiological data improves as well. Furthermore, we show that, within our model, the primary mechanism to reproduce a realistic evolution of the awareness during an epidemic, is the one due to globally available information. This result highlights how crucial is the role of mass media and educational campaigns in influencing the epidemic spreading of infectious

Information behavior versus communication: application models in multidisciplinary settings

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Cecília Morena Maria da Silva

2015-05-01

Full Text Available This paper deals with the information behavior as support for models of communication design in the areas of Information Science, Library and Music. The communication models proposition is based on models of Tubbs and Moss (2003, Garvey and Griffith (1972, adapted by Hurd (1996 and Wilson (1999. Therefore, the questions arose: (i what are the informational skills required of librarians who act as mediators in scholarly communication process and informational user behavior in the educational environment?; (ii what are the needs of music related researchers and as produce, seek, use and access the scientific knowledge of your area?; and (iii as the contexts involved in scientific collaboration processes influence in the scientific production of information science field in Brazil? The article includes a literature review on the information behavior and its insertion in scientific communication considering the influence of context and/or situation of the objects involved in motivating issues. The hypothesis is that the user information behavior in different contexts and situations influence the definition of a scientific communication model. Finally, it is concluded that the same concept or a set of concepts can be used in different perspectives, reaching up, thus, different results.

Current definition and a generalized federbush model

International Nuclear Information System (INIS)

Singh, L.P.S.; Hagen, C.R.

1978-01-01

The Federbush model is studied, with particular attention being given to the definition of currents. Inasmuch as there is no a priori restriction of local gauge invariance, the currents in the interacting case can be defined more generally than in Q.E.D. It is found that two arbitrary parameters are thereby introduced into the theory. Lowest order perturbation calculations for the current correlation functions and the Fermion propagators indicate that the theory admits a whole class of solutions dependent upon these parameters with the closed solution of Federbush emerging as a special case. The theory is shown to be locally covariant, and a conserved energy--momentum tensor is displayed. One finds in addition that the generators of gauge transformations for the fields are conserved. Finally it is shown that the general theory yields the Federbush solution if suitable Thirring model type counterterms are added

A motivational model for environmentally responsible behavior.

Science.gov (United States)

Tabernero, Carmen; Hernández, Bernardo

2012-07-01

This paper presents a study examining whether self-efficacy and intrinsic motivation are related to environmentally responsible behavior (ERB). The study analysed past environmental behavior, self-regulatory mechanisms (self-efficacy, satisfaction, goals), and intrinsic and extrinsic motivation in relation to ERBs in a sample of 156 university students. Results show that all the motivational variables studied are linked to ERB. The effects of self-efficacy on ERB are mediated by the intrinsic motivation responses of the participants. A theoretical model was created by means of path analysis, revealing the power of motivational variables to predict ERB. Structural equation modeling was used to test and fit the research model. The role of motivational variables is discussed with a view to creating adequate learning contexts and experiences to generate interest and new sensations in which self-efficacy and affective reactions play an important role.

A mixture theory approach to model co- and counter-current two-phase flow in porous media accounting for viscous coupling

Science.gov (United States)

Qiao, Y.; Andersen, P. Ø.; Evje, S.; Standnes, D. C.

2018-02-01

It is well known that relative permeabilities can depend on the flow configuration and they are commonly lower during counter-current flow as compared to co-current flow. Conventional models must deal with this by manually changing the relative permeability curves depending on the observed flow regime. In this paper we use a novel two-phase momentum-equation-approach based on general mixture theory to generate effective relative permeabilities where this dependence (and others) is automatically captured. In particular, this formulation includes two viscous coupling effects: (i) Viscous drag between the flowing phases and the stagnant porous rock; (ii) viscous drag caused by momentum transfer between the flowing phases. The resulting generalized model will predict that during co-current flow the faster moving fluid accelerates the slow fluid, but is itself decelerated, while for counter-current flow they are both decelerated. The implications of these mechanisms are demonstrated by investigating recovery of oil from a matrix block surrounded by water due to a combination of gravity drainage and spontaneous imbibition, a situation highly relevant for naturally fractured reservoirs. We implement relative permeability data obtained experimentally through co-current flooding experiments and then explore the model behavior for different flow cases ranging from counter-current dominated to co-current dominated. In particular, it is demonstrated how the proposed model seems to offer some possible interesting improvements over conventional modeling by providing generalized mobility functions that automatically are able to capture more correctly different flow regimes for one and the same parameter set.

A Dynamic Object Behavior Model and Implementation Based on Computational Reflection

Institute of Scientific and Technical Information of China (English)

HE Cheng-wan; HE Fei; HE Ke-qing

2005-01-01

A dynamic object behavior model based on computational reflection is proposed. This model consists of function level and meta level, the meta objects in meta level manage the base objects and behaviors in function level, including dynamic binding and unbinding of base object and behavior.We implement this model with RoleJava Language, which is our self linguistic extension of the Java Language. Meta Objects are generated automatically at compile-time, this makes the reflecton mechanism transparent to programmers. Finally an example applying this model to a banking system is presented.

Modeling, numerical simulation, and nonlinear dynamic behavior analysis of PV microgrid-connected inverter with capacitance catastrophe

Science.gov (United States)

Li, Sichen; Liao, Zhixian; Luo, Xiaoshu; Wei, Duqu; Jiang, Pinqun; Jiang, Qinghong

2018-02-01

The value of the output capacitance (C) should be carefully considered when designing a photovoltaic (PV) inverter since it can cause distortion in the working state of the circuit, and the circuit produces nonlinear dynamic behavior. According to Kirchhoff’s laws and the characteristics of an ideal operational amplifier for a strict piecewise linear state equation, a circuit simulation model is constructed to study the system parameters (time, C) for the current passing through an inductor with an inductance of L and the voltage across the capacitor with a capacitance of C. The developed simulation model uses Runge-Kutta methods to solve the state equations. This study focuses on predicting the fault of the circuit from the two aspects of the harmonic distortion and simulation results. Moreover, the presented model is also used to research the working state of the system in the case of a load capacitance catastrophe. The nonlinear dynamic behaviors in the inverter are simulated and verified.

Modeling of High Temperature Oxidation Behavior of FeCrAl Alloy by using Artificial Neural Network

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Joon; Ryu, Ho Jin [KAIST, Daejeon (Korea, Republic of)

2016-10-15

Refractory alloys are candidate materials for replacing current zirconium-base cladding of light water reactors and they retain significant creep resistance and mechanical strength at high temperatures up to 1500 ℃ due to their high melting temperature. Thermal neutron cross sections of refractory metals are higher than that of zirconium, however the loss of neutron can be overcome by reducing cladding thickness which can be facilitated with enhanced mechanical properties. However, most refractory metals show the poor oxidation resistance at a high temperature. Oxidation behaviors of the various compositions of FeCrAl alloys in high temperature conditions were modeled by using Bayesian neural network. The automatic relevance determination (ARD) technique represented the influence of the composition of alloying elements on the oxidation resistance of FeCrAl alloys. This model can be utilized to understand the tendency of oxidation behavior along the composition of each element and prove the applicability of neural network modeling for the development of new cladding material of light water reactors.

Relational models for knowledge sharing behavior

NARCIS (Netherlands)

Boer, N.I.; Berends, J.J.; Baalen, P.

2011-01-01

In this paper we explore the relational dimension of knowledge sharing behavior by proposing a comprehensive theoretical framework for studying knowledge sharing in organizations. This theoretical framework originates from (Fiske, 1991) and (Fiske, 1992) Relational Models Theory (RMT). The RMT

Modeling Adaptive Behavior for Systems Design

DEFF Research Database (Denmark)

Rasmussen, Jens

1994-01-01

Field studies in modern work systems and analysis of recent major accidents have pointed to a need for better models of the adaptive behavior of individuals and organizations operating in a dynamic and highly competitive environment. The paper presents a discussion of some key characteristics.......) The basic difference between the models of system functions used in engineering and design and those evolving from basic research within the various academic disciplines and finally 3.) The models and methods required for closed-loop, feedback system design....

Advancing Models and Theories for Digital Behavior Change Interventions.

Science.gov (United States)

Hekler, Eric B; Michie, Susan; Pavel, Misha; Rivera, Daniel E; Collins, Linda M; Jimison, Holly B; Garnett, Claire; Parral, Skye; Spruijt-Metz, Donna

2016-11-01

To be suitable for informing digital behavior change interventions, theories and models of behavior change need to capture individual variation and changes over time. The aim of this paper is to provide recommendations for development of models and theories that are informed by, and can inform, digital behavior change interventions based on discussions by international experts, including behavioral, computer, and health scientists and engineers. The proposed framework stipulates the use of a state-space representation to define when, where, for whom, and in what state for that person, an intervention will produce a targeted effect. The "state" is that of the individual based on multiple variables that define the "space" when a mechanism of action may produce the effect. A state-space representation can be used to help guide theorizing and identify crossdisciplinary methodologic strategies for improving measurement, experimental design, and analysis that can feasibly match the complexity of real-world behavior change via digital behavior change interventions. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Modeling collective animal behavior with a cognitive perspective: a methodological framework.

Directory of Open Access Journals (Sweden)

Sebastian Weitz

Full Text Available The last decades have seen an increasing interest in modeling collective animal behavior. Some studies try to reproduce as accurately as possible the collective dynamics and patterns observed in several animal groups with biologically plausible, individual behavioral rules. The objective is then essentially to demonstrate that the observed collective features may be the result of self-organizing processes involving quite simple individual behaviors. Other studies concentrate on the objective of establishing or enriching links between collective behavior researches and cognitive or physiological ones, which then requires that each individual rule be carefully validated. Here we discuss the methodological consequences of this additional requirement. Using the example of corpse clustering in ants, we first illustrate that it may be impossible to discriminate among alternative individual rules by considering only observational data collected at the group level. Six individual behavioral models are described: They are clearly distinct in terms of individual behaviors, they all reproduce satisfactorily the collective dynamics and distribution patterns observed in experiments, and we show theoretically that it is strictly impossible to discriminate two of these models even in the limit of an infinite amount of data whatever the accuracy level. A set of methodological steps are then listed and discussed as practical ways to partially overcome this problem. They involve complementary experimental protocols specifically designed to address the behavioral rules successively, conserving group-level data for the overall model validation. In this context, we highlight the importance of maintaining a sharp distinction between model enunciation, with explicit references to validated biological concepts, and formal translation of these concepts in terms of quantitative state variables and fittable functional dependences. Illustrative examples are provided of the

Phase Transition Behavior in a Neutral Evolution Model

Science.gov (United States)

King, Dawn; Scott, Adam; Maric, Nevena; Bahar, Sonya

2014-03-01

The complexity of interactions among individuals and between individuals and the environment make agent based modeling ideal for studying emergent speciation. This is a dynamically complex problem that can be characterized via the critical behavior of a continuous phase transition. Concomitant with the main tenets of natural selection, we allow organisms to reproduce, mutate, and die within a neutral phenotype space. Previous work has shown phase transition behavior in an assortative mating model with variable fitness landscapes as the maximum mutation size (μ) was varied (Dees and Bahar, 2010). Similarly, this behavior was recently presented in the work of Scott et al. (2013), even on a completely neutral landscape, for bacterial-like fission as well as for assortative mating. Here we present another neutral model to investigate the `critical' phase transition behavior of three mating types - assortative, bacterial, and random - in a phenotype space as a function of the percentage of random death. Results show two types of phase transitions occurring for the parameters of the population size and the number of clusters (an analogue of species), indicating different evolutionary dynamics for system survival and clustering. This research was supported by funding from: University of Missouri Research Board and James S. McDonnell Foundation.

A model of multi-purpose shopping trip behavior

NARCIS (Netherlands)

Arentze, T.A.; Borgers, A.W.J.; Timmermans, H.J.P.

1993-01-01

Existing utility-based models of complex choice behavior do not adequately deal with the interdependencies of chained choices. In this paper, we introduce a model of multi-purpose shopping which is aimed at overcoming this shortcoming. In the proposed model, dependencies between choices within as

Empirical modeling of dynamic behaviors of pneumatic artificial muscle actuators.

Science.gov (United States)

Wickramatunge, Kanchana Crishan; Leephakpreeda, Thananchai

2013-11-01

Pneumatic Artificial Muscle (PAM) actuators yield muscle-like mechanical actuation with high force to weight ratio, soft and flexible structure, and adaptable compliance for rehabilitation and prosthetic appliances to the disabled as well as humanoid robots or machines. The present study is to develop empirical models of the PAM actuators, that is, a PAM coupled with pneumatic control valves, in order to describe their dynamic behaviors for practical control design and usage. Empirical modeling is an efficient approach to computer-based modeling with observations of real behaviors. Different characteristics of dynamic behaviors of each PAM actuator are due not only to the structures of the PAM actuators themselves, but also to the variations of their material properties in manufacturing processes. To overcome the difficulties, the proposed empirical models are experimentally derived from real physical behaviors of the PAM actuators, which are being implemented. In case studies, the simulated results with good agreement to experimental results, show that the proposed methodology can be applied to describe the dynamic behaviors of the real PAM actuators. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Engineering Student's Ethical Awareness and Behavior: A New Motivational Model.

Science.gov (United States)

Bairaktarova, Diana; Woodcock, Anna

2017-08-01

Professional communities are experiencing scandals involving unethical and illegal practices daily. Yet it should not take a national major structure failure to highlight the importance of ethical awareness and behavior, or the need for the development and practice of ethical behavior in engineering students. Development of ethical behavior skills in future engineers is a key competency for engineering schools as ethical behavior is a part of the professional identity and practice of engineers. While engineering educators have somewhat established instructional methods to teach engineering ethics, they still rely heavily on teaching ethical awareness, and pay little attention to how well ethical awareness predicts ethical behavior. However the ability to exercise ethical judgement does not mean that students are ethically educated or likely to behave in an ethical manner. This paper argues measuring ethical judgment is insufficient for evaluating the teaching of engineering ethics, because ethical awareness has not been demonstrated to translate into ethical behavior. The focus of this paper is to propose a model that correlates with both, ethical awareness and ethical behavior. This model integrates the theory of planned behavior, person and thing orientation, and spheres of control. Applying this model will allow educators to build confidence and trust in their students' ability to build a professional identity and be prepared for the engineering profession and practice.

A novel approach to model the transient behavior of solid-oxide fuel cell stacks

Science.gov (United States)

Menon, Vikram; Janardhanan, Vinod M.; Tischer, Steffen; Deutschmann, Olaf

2012-09-01

This paper presents a novel approach to model the transient behavior of solid-oxide fuel cell (SOFC) stacks in two and three dimensions. A hierarchical model is developed by decoupling the temperature of the solid phase from the fluid phase. The solution of the temperature field is considered as an elliptic problem, while each channel within the stack is modeled as a marching problem. This paper presents the numerical model and cluster algorithm for coupling between the solid phase and fluid phase. For demonstration purposes, results are presented for a stack operated on pre-reformed hydrocarbon fuel. Transient response to load changes is studied by introducing step changes in cell potential and current. Furthermore, the effect of boundary conditions and stack materials on response time and internal temperature distribution is investigated.

Determinants of Consumers’ Pro-Environmental Behavior – Toward an Integrated Model

Directory of Open Access Journals (Sweden)

Octav-Ionuţ Macovei

2015-08-01

Full Text Available This paper aims at constructing a model which will explain consumers’ pro-environmental behavior by analyzing its direct and indirect predictors. To achieve this, variables from wellestablished models and theories were employed, such as Schwartz’s Norm Activation Theory (NAT, Stern’s Value-belief-norms Theory (VBN and Ajzen’s Theory of Planned Behavior (TPB. Important variables like perceived behavioral control, normative beliefs, awareness of the consequences of environmental problems, Compatibility with a pro-environmental behaviour, attitude towards a proenvironmental behavior and intention to behave in a pro-environmental manner are considered to be determinants of consumers’ pro-environmental behavior. All these variables were discussed and assembled in an integrated research model which can be validated through a quantitative survey. Each variable was described at a conceptual and operational level, items and scales being proposed for each one The proposed model will offer to organizations a valuable green marketing tool which can be used in the fight for environment protection. The proposed model is unique can be used as a solid based for future research.

Modelling of the ring current in Saturn's magnetosphere

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G. Giampieri

2004-01-01

Full Text Available The existence of a ring current inside Saturn's magnetosphere was first suggested by Smith et al. (1980 and Ness et al. (1981, 1982, in order to explain various features in the magnetic field observations from the Pioneer 11 and Voyager 1 and 2 spacecraft. Connerney et al. (1983 formalized the equatorial current model, based on previous modelling work of Jupiter's current sheet and estimated its parameters from the two Voyager data sets. Here, we investigate the model further, by reconsidering the data from the two Voyager spacecraft, as well as including the Pioneer 11 flyby data set.

First, we obtain, in closed form, an analytic expression for the magnetic field produced by the ring current. We then fit the model to the external field, that is the difference between the observed field and the internal magnetic field, considering all the available data. In general, through our global fit we obtain more accurate parameters, compared to previous models. We point out differences between the model's parameters for the three flybys, and also investigate possible deviations from the axial and planar symmetries assumed in the model. We conclude that an accurate modelling of the Saturnian disk current will require taking into account both of the temporal variations related to the condition of the magnetosphere, as well as non-axisymmetric contributions due to local time effects.

Key words. Magnetospheric physics (current systems; planetary magnetospheres; plasma sheet

Behavioral Reference Model for Pervasive Healthcare Systems.

Science.gov (United States)

Tahmasbi, Arezoo; Adabi, Sahar; Rezaee, Ali

2016-12-01

The emergence of mobile healthcare systems is an important outcome of application of pervasive computing concepts for medical care purposes. These systems provide the facilities and infrastructure required for automatic and ubiquitous sharing of medical information. Healthcare systems have a dynamic structure and configuration, therefore having an architecture is essential for future development of these systems. The need for increased response rate, problem limited storage, accelerated processing and etc. the tendency toward creating a new generation of healthcare system architecture highlight the need for further focus on cloud-based solutions for transfer data and data processing challenges. Integrity and reliability of healthcare systems are of critical importance, as even the slightest error may put the patients' lives in danger; therefore acquiring a behavioral model for these systems and developing the tools required to model their behaviors are of significant importance. The high-level designs may contain some flaws, therefor the system must be fully examined for different scenarios and conditions. This paper presents a software architecture for development of healthcare systems based on pervasive computing concepts, and then models the behavior of described system. A set of solutions are then proposed to improve the design's qualitative characteristics including, availability, interoperability and performance.

Developing a Behavioral Model for Mobile Phone-Based Diabetes Interventions

Science.gov (United States)

Nundy, Shantanu; Dick, Jonathan J.; Solomon, Marla C.; Peek, Monica E.

2013-01-01

Objectives Behavioral models for mobile phone-based diabetes interventions are lacking. This study explores the potential mechanisms by which a text message-based diabetes program affected self-management among African-Americans. Methods We conducted in-depth, individual interviews among 18 African-American patients with type 2 diabetes who completed a 4-week text message-based diabetes program. Each interview was audio- taped, transcribed verbatim, and imported into Atlas.ti software. Coding was done iteratively. Emergent themes were mapped onto existing behavioral constructs and then used to develop a novel behavioral model for mobile phone-based diabetes self-management programs. Results The effects of the text message-based program went beyond automated reminders. The constant, daily communications reduced denial of diabetes and reinforced the importance of self-management (Rosenstock Health Belief Model). Responding positively to questions about self-management increased mastery experience (Bandura Self-Efficacy). Most surprisingly, participants perceived the automated program as a “friend” and “support group” that monitored and supported their self-management behaviors (Barrera Social Support). Conclusions A mobile phone-based diabetes program affected self-management through multiple behavioral constructs including health beliefs, self-efficacy, and social support. Practice implications: Disease management programs that utilize mobile technologies should be designed to leverage existing models of behavior change and can address barriers to self-management associated with health disparities. PMID:23063349

Assessing allometric models to predict vegetative growth of mango (Mangifera indica; Anacardiaceae) at the current-year branch scale.

Science.gov (United States)

Normand, Frédéric; Lauri, Pierre-Éric

2012-03-01

Accurate and reliable predictive models are necessary to estimate nondestructively key variables for plant growth studies such as leaf area and leaf, stem, and total biomass. Predictive models are lacking at the current-year branch scale despite the importance of this scale in plant science. We calibrated allometric models to estimate leaf area and stem and branch (leaves + stem) mass of current-year branches, i.e., branches several months old studied at the end of the vegetative growth season, of four mango cultivars on the basis of their basal cross-sectional area. The effects of year, site, and cultivar were tested. Models were validated with independent data and prediction accuracy was evaluated with the appropriate statistics. Models revealed a positive allometry between dependent and independent variables, whose y-intercept but not the slope, was affected by the cultivar. The effects of year and site were negligible. For each branch characteristic, cultivar-specific models were more accurate than common models built with pooled data from the four cultivars. Prediction quality was satisfactory but with data dispersion around the models, particularly for large values. Leaf area and stem and branch mass of mango current-year branches could be satisfactorily estimated on the basis of branch basal cross-sectional area with cultivar-specific allometric models. The results suggested that, in addition to the heteroscedastic behavior of the variables studied, model accuracy was probably related to the functional plasticity of branches in relation to the light environment and/or to the number of growth units composing the branches.

EMPIRICAL MODELS FOR DESCRIBING FIRE BEHAVIOR IN BRAZILIAN COMMERCIAL EUCALYPT PLANTATIONS

Directory of Open Access Journals (Sweden)

Benjamin Leonardo Alves White

2016-12-01

Full Text Available Modeling forest fire behavior is an important task that can be used to assist in fire prevention and suppression operations. However, according to previous studies, the existing common worldwide fire behavior models used do not correctly estimate the fire behavior in Brazilian commercial hybrid eucalypt plantations. Therefore, this study aims to build new empirical models to predict the fire rate of spread, flame length and fuel consumption for such vegetation. To meet these objectives, 105 laboratory experimental burns were done, where the main fuel characteristics and weather variables that influence fire behavior were controlled and/or measured in each experiment. Dependent and independent variables were fitted through multiple regression analysis. The fire rate of spread proposed model is based on the wind speed, fuel bed bulk density and 1-h dead fuel moisture content (r2 = 0.86; the flame length model is based on the fuel bed depth, 1-h dead fuel moisture content and wind speed (r2 = 0.72; the fuel consumption proposed model has the 1-h dead fuel moisture, fuel bed bulk density and 1-h dead dry fuel load as independent variables (r2= 0.80. These models were used to develop a new fire behavior software, the “Eucalyptus Fire Safety System”.

MHD Modeling of Conductors at Ultra-High Current Density

International Nuclear Information System (INIS)

ROSENTHAL, STEPHEN E.; DESJARLAIS, MICHAEL P.; SPIELMAN, RICK B.; STYGAR, WILLIAM A.; ASAY, JAMES R.; DOUGLAS, M.R.; HALL, C.A.; FRESE, M.H.; MORSE, R.L.; REISMAN, D.B.

2000-01-01

In conjunction with ongoing high-current experiments on Sandia National Laboratories' Z accelerator, the authors have revisited a problem first described in detail by Heinz Knoepfel. Unlike the 1-Tesla MITLs of pulsed power accelerators used to produce intense particle beams, Z's disc transmission line (downstream of the current addition) is in a 100--1,200 Tesla regime, so its conductors cannot be modeled simply as static infinite conductivity boundaries. Using the MHD code MACH2 they have been investigating the conductor hydrodynamics, characterizing the joule heating, magnetic field diffusion, and material deformation, pressure, and velocity over a range of current densities, current rise-times, and conductor materials. Three purposes of this work are (1) to quantify power flow losses owing to ultra-high magnetic fields, (2) to model the response of VISAR diagnostic samples in various configurations on Z, and (3) to incorporate the most appropriate equation of state and conductivity models into the MHD computations. Certain features are strongly dependent on the details of the conductivity model

MHD Modeling of Conductors at Ultra-High Current Density

International Nuclear Information System (INIS)

Rosenthal, S.E.; Asay, J.R.; Desjarlais, M.P.; Douglas, M.R.; Frese, M.H.; Hall, C.A.; Morse, R.L.; Reisman, D.; Spielman, R.B.; Stygar, W.A.

1999-01-01

In conjunction with ongoing high-current experiments on Sandia National Laboratories' Z accelerator we have revisited a problem first described in detail by Heinz Knoepfel. MITLs of previous pulsed power accelerators have been in the 1-Tesla regime. Z's disc transmission line (downstream of the current addition) is in a 100-1200 Tesla regime, so its conductors cannot be modeled simply as static infinite conductivity boundaries. Using the MHD code MACH2 we have been investigating conductor hydrodynamics, characterizing the joule heating, magnetic field diffusion, and material deformation, pressure, and velocity over a range of current densities, current rise-times, and conductor materials. Three purposes of this work are ( 1) to quantify power flow losses owing to ultra-high magnetic fields, (2) to model the response of VISAR diagnostic samples in various configurations on Z, and (3) to incorporate the most appropriate equation of state and conductivity models into our MHD computations. Certain features are strongly dependent on the details of the conductivity model. Comparison with measurements on Z will be discussed

Coupled Interfacial Tension and Phase Behavior Model Based on Micellar Curvatures

KAUST Repository

Torrealba, V. A.

2017-11-08

This article introduces a consistent and robust model that predicts interfacial tensions for all microemulsion Winsor types and overall compositions. The model incorporates film bending arguments and Huh\\'s equation and is coupled to phase behavior so that simultaneous tuning of both interfacial tension (IFT) and phase behavior is possible. The oil-water interfacial tension and characteristic length are shown to be related to each other through the hydrophilic-lipophilic deviation (HLD). The phase behavior is tied to the micelle curvatures, without the need for using the net average curvature (NAC). The interfacial tension model is related to solubilization ratios in order to introduce a coupled interfacial tension-phase behavior model for all phase environments. The approach predicts two- and three-phase interfacial tensions and phase behavior (i.e., tie lines and tie triangles) for changes in composition and HLD input parameters, such as temperature, pressure, surfactant structure, and oil equivalent alkane carbon number. Comparisons to experimental data show excellent fits and predictive capability.

From bench to bed: putative animal models of REM sleep behavior disorder (RBD).

Science.gov (United States)

Krenzer, Martina; Lu, Jun; Mayer, Geert; Oertel, Wolfgang

2013-04-01

REM behavior disorder (RBD) is a parasomnia characterized by REM sleep without atonia, leading to abnormal and potentially injurious behavior during REM sleep. It is considered one of the most specific predictors of neurodegenerative disorders, such as Parkinson's disease. In this paper, we provide an overview of animal models contributing to our current understanding of REM-associated atonia, and, as a consequence, the pathophysiology of RBD. The generator of REM-associated atonia is located in glutamatergic neurons of the pontine sublaterodorsal nucleus (SLD), as shown in cats, rats and mice. These findings are supported by clinical cases of patients with lesions of the homologous structure in humans. Glutamatergic SLD neurons, presumably in conjunction with others, project to (a) the ventromedial medulla, where they either directly target inhibitory interneurons to alpha motor neurons or are relayed, and (b) the spinal cord directly. At the spinal level, alpha motor neurons are inhibited by GABAergic and glycinergic interneurons. Our current understanding is that lesions of the glutamatergic SLD are the key factor for REM sleep behavior disorder. However, open questions remain, e.g. other features of RBD (such as the typically aggressive dream content) or the frequent progression from idiopathic RBD to neurodegenerative disorders, to name only a few. In order to elucidate these questions, a constant interaction between basic and clinical researchers is required, which might, ultimately, create an early therapeutic window for neurodegenerative disorders.

Explaining clinical behaviors using multiple theoretical models

OpenAIRE

Eccles, Martin P; Grimshaw, Jeremy M; MacLennan, Graeme; Bonetti, Debbie; Glidewell, Liz; Pitts, Nigel B; Steen, Nick; Thomas, Ruth; Walker, Anne; Johnston, Marie

2012-01-01

Abstract Background In the field of implementation research, there is an increased interest in use of theory when designing implementation research studies involving behavior change. In 2003, we initiated a series of five studies to establish a scientific rationale for interventions to translate research findings into clinical practice by exploring the performance of a number of different, commonly used, overlapping behavioral theories and models. We reflect on the strengths and weaknesses of...

Psychopathy and Deviant Workplace Behavior: A Comparison of Two Psychopathy Models.

Science.gov (United States)

Carre, Jessica R; Mueller, Steven M; Schleicher, Karly M; Jones, Daniel N

2018-04-01

Although psychopathy is an interpersonally harmful construct, few studies have compared different psycho athy models in predicting different types of workplace deviance. We examined how the Triarchic Psychopathy Model (TRI-PM) and the Self-Report Psychopathy-Short Form (SRP-SF) predicted deviant workplace behaviors in two forms: sexual harassment and deviant work behaviors. Using structural equations modeling, the latent factor of psychopathy was predictive for both types of deviant workplace behavior. Specifically, the SRP-SF signif cantly predicted both measures of deviant workplace behavior. With respect to the TRI-PM, meanness and disinhibition significantly predicted higher scores of workplace deviance and workplace sexual harassment measures. Future research needs to investigate the influence of psychopathy on deviant workplace behaviors, and consider the measures they use when they investigate these constructs.

Electro-mechanical behaviors of composite superconducting strand with filament breakage

International Nuclear Information System (INIS)

Wang, Xu; Gao, Yuanwen; Zhou, Youhe

2016-01-01

Highlights: • The electromechanical behaviors of the superconducting (SC) strand are investigated. • A 3D FEM model for bending behaviors and electric properties of strand is developed. • The influence of breakage of filaments on the critical current of SC strand is calculated. • The impact of current transfer length on the electric properties of SC strand is discussed. - Abstract: The bending behaviors of superconducting strand with typical multi-filament twist configuration are investigated based on a three-dimensional finite element method (FEM) model, named as the Multi-filament twist model, of the strand. In this 3D FEM model, the impacts of initial thermal residual stress, filament-breakage and its evaluation are taken into accounts. The mechanical responses of the strand under bending load are studied with the factors taken into consideration one by one. The distribution of the damage of the filaments and its evolution and the movement of the neutral axis caused by it are studied and displayed in detail. Besides, taking the advantages of the Multi-filament twist model, the normalized critical current of the strand under bending load is also calculated based on the invariant temperature and field strain functions. In addition, the non-negligible influences of the pitch length of the filaments on both the mechanical behaviors and the normalized critical current are discussed. The stress-strain characteristics of the strand under tensile load and the normalized critical current of it under axial and bending loads resulting from the Multi-filament twist model show good agreement with the experimental data.

Electro-mechanical behaviors of composite superconducting strand with filament breakage

Energy Technology Data Exchange (ETDEWEB)

Wang, Xu [Key Laboratory of Mechanics on Environment and Disaster in Western China, The Ministry of Education of China, Lanzhou, Gansu 730000 (China); Department of Mechanics and Engineering Science, College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, Gansu 730000 (China); Gao, Yuanwen, E-mail: ywgao@lzu.edu.cn [Key Laboratory of Mechanics on Environment and Disaster in Western China, The Ministry of Education of China, Lanzhou, Gansu 730000 (China); Department of Mechanics and Engineering Science, College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, Gansu 730000 (China); Zhou, Youhe [Key Laboratory of Mechanics on Environment and Disaster in Western China, The Ministry of Education of China, Lanzhou, Gansu 730000 (China); Department of Mechanics and Engineering Science, College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, Gansu 730000 (China)

2016-10-15

Highlights: • The electromechanical behaviors of the superconducting (SC) strand are investigated. • A 3D FEM model for bending behaviors and electric properties of strand is developed. • The influence of breakage of filaments on the critical current of SC strand is calculated. • The impact of current transfer length on the electric properties of SC strand is discussed. - Abstract: The bending behaviors of superconducting strand with typical multi-filament twist configuration are investigated based on a three-dimensional finite element method (FEM) model, named as the Multi-filament twist model, of the strand. In this 3D FEM model, the impacts of initial thermal residual stress, filament-breakage and its evaluation are taken into accounts. The mechanical responses of the strand under bending load are studied with the factors taken into consideration one by one. The distribution of the damage of the filaments and its evolution and the movement of the neutral axis caused by it are studied and displayed in detail. Besides, taking the advantages of the Multi-filament twist model, the normalized critical current of the strand under bending load is also calculated based on the invariant temperature and field strain functions. In addition, the non-negligible influences of the pitch length of the filaments on both the mechanical behaviors and the normalized critical current are discussed. The stress-strain characteristics of the strand under tensile load and the normalized critical current of it under axial and bending loads resulting from the Multi-filament twist model show good agreement with the experimental data.

A hydrodynamic model of nearshore waves and wave-induced currents

Directory of Open Access Journals (Sweden)

Ahmed Khaled Seif

2011-09-01

Full Text Available In This study develops a quasi-three dimensional numerical model of wave driven coastal currents with accounting the effects of the wave-current interaction and the surface rollers. In the wave model, the current effects on wave breaking and energy dissipation are taken into account as well as the wave diffraction effect. The surface roller associated with wave breaking was modeled based on a modification of the equations by Dally and Brown (1995 and Larson and Kraus (2002. Furthermore, the quasi-three dimensional model, which based on Navier-Stokes equations, was modified in association with the surface roller effect, and solved using frictional step method. The model was validated by data sets obtained during experiments on the Large Scale Sediment Transport Facility (LSTF basin and the Hazaki Oceanographical Research Station (HORS. Then, a model test against detached breakwater was carried out to investigate the performance of the model around coastal structures. Finally, the model was applied to Akasaki port to verify the hydrodynamics around coastal structures. Good agreements between computations and measurements were obtained with regard to the cross-shore variation in waves and currents in nearshore and surf zone.

Physics-based electromechanical model of IPMC considering various underlying currents

Science.gov (United States)

Pugal, D.; Kim, K. J.; Palmre, V.; Leang, K. K.; Aabloo, A.

2012-04-01

Experiments indicate that the electrodes affect the charge dynamics, and therefore actuation of ionic polymermetal composite (IPMC) via three different types of currents - electric potential induced ionic current, leakage current, and electrochemical current if approximately higher than 2 V voltage is applied to a typical 200 μm thick IPMC. The ionic current via charge accumulation near the electrodes is the direct cause of the osmotic and electrostatic stresses in the polymer and therefore carries the major role in the actuation of IPMC. However, the leakage and the electrochemical - electrolysis in case of water based IPMCs - currents do not affect the actuation dynamics as directly but cause potential gradients on the electrodes. These in turn affect the ionic current. A physics based finite element (FE) model was developed to incorporate the effect of the electrodes and three different types of currents in the actuation calculations. The Poisson-Nernst-Planck system of equations is used in the model to describe the ionic current and the Butler-Volmer relation is used to describe the electrolysis current for different applied voltages and IPMC thicknesses. To validate the model, calculated tip deflection, applied net current, and potential drop in case of various IPMC thicknesses and applied voltages are compared to experimental data.

The Current Account and the Interest Differential in Canada

OpenAIRE

Martin Boileau; Michel Normandin

2004-01-01

For post-1975 Canadian data, we document the joint behavior of output, the current account, and the interest differential at the business cycle frequency. We also interpret the joint behavior using a simple small open economy model. Our simple model assumes that agents have access to world international financial markets, but face country-specific interest rate on their holdings of world assets. The interest differential depends negatively on the country’s net foreign asset position. We find ...

Models of behavioral change and adaptation

NARCIS (Netherlands)

Rasouli, S.; Timmermans, H.J.P.; Zhang, J.

2017-01-01

This chapter explains and summarizes models of behavioral change and adaptation, which have received less application in the life choice analysis associated with urban policy. Related to various life choices, life trajectory events are major decisions with a relatively long-lasting impact, such as

A conceptual model of investor behavior

NARCIS (Netherlands)

Lovric, M.; Kaymak, U.; Spronk, J.; Nefti, S.; Gray, J.O.

2010-01-01

Behavioral finance is a subdiscipline of finance that uses insights from cogni tive and social psychology to enrich our knowledge of how investors make their financial decisions. Agent-based artificial financial markets are bottomup models of financial markets that start from the micro level of

Reducing Societal Obesity: Establishing a Separate Exercise Model through Studies of Group Behavior.

Science.gov (United States)

Puterbaugh, J S

2016-01-01

The past 50 years has brought attention to high and increasing levels of human obesity in most of the industrialized world. The medical profession has noticed, has evaluated, and has developed models for studying, preventing, and reversing obesity. The current model prescribes activity in specific quantities such as days, minutes, heart rates, and footfalls. Although decreased levels of activity have come from changes revolving around built environments and social networks, the existing medical model to lower body weights by increasing activity remains individually prescriptive. It is not working. The study of societal obesity precludes the individual and must involve group behavioral studies. Such studies necessitate acquiring separate tools and, therefore, require a significant change in the evaluation and treatment of obesity. Finding groups with common activities and lower levels of obesity would allow the development of new models of land use and encourage active lifestyles through shared interests.

Modeling the current distribution in HTS tapes with transport current and applied magnetic field

NARCIS (Netherlands)

Yazawa, T.; Yazawa, Takashi; Rabbers, J.J.; Chevtchenko, O.A.; ten Haken, Bernard; ten Kate, Herman H.J.; Maeda, Hideaki

1999-01-01

A numerical model is developed for the current distribution in a high temperature superconducting (HTS) tape, (Bi,Pb)2Sr2 Ca2Cu3Ox-Ag, subjected to a combination of a transport current and an applied magnetic field. This analysis is based on a two-dimensional formulation of Maxwell's equations in

The Bootstrap Current and Neutral Beam Current Drive in DIII-D

International Nuclear Information System (INIS)

Politzer, P.A.

2005-01-01

Noninductive current drive is an essential part of the implementation of the DIII-D Advanced Tokamak program. For an efficient steady-state tokamak reactor, the plasma must provide close to 100% bootstrap fraction (f bs ). For noninductive operation of DIII-D, current drive by injection of energetic neutral beams [neutral beam current drive (NBCD)] is also important. DIII-D experiments have reached ∼80% bootstrap current in stationary discharges without inductive current drive. The remaining current is ∼20% NBCD. This is achieved at β N [approximately equal to] β p > 3, but at relatively high q 95 (∼10). In lower q 95 Advanced Tokamak plasmas, f bs ∼ 0.6 has been reached in essentially noninductive plasmas. The phenomenology of high β p and β N plasmas without current control is being studied. These plasmas display a relaxation oscillation involving repetitive formation and collapse of an internal transport barrier. The frequency and severity of these events increase with increasing β, limiting the achievable average β and causing modulation of the total current as well as the pressure. Modeling of both bootstrap and NBCD currents is based on neoclassical theory. Measurements of the total bootstrap and NBCD current agree with calculations. A recent experiment based on the evolution of the transient voltage profile after an L-H transition shows that the more recent bootstrap current models accurately describe the plasma behavior. The profiles and the parametric dependences of the local neutral beam-driven current density have not yet been compared with theory

Bayesian network model of crowd emotion and negative behavior

Science.gov (United States)

Ramli, Nurulhuda; Ghani, Noraida Abdul; Hatta, Zulkarnain Ahmad; Hashim, Intan Hashimah Mohd; Sulong, Jasni; Mahudin, Nor Diana Mohd; Rahman, Shukran Abd; Saad, Zarina Mat

2014-12-01

The effects of overcrowding have become a major concern for event organizers. One aspect of this concern has been the idea that overcrowding can enhance the occurrence of serious incidents during events. As one of the largest Muslim religious gathering attended by pilgrims from all over the world, Hajj has become extremely overcrowded with many incidents being reported. The purpose of this study is to analyze the nature of human emotion and negative behavior resulting from overcrowding during Hajj events from data gathered in Malaysian Hajj Experience Survey in 2013. The sample comprised of 147 Malaysian pilgrims (70 males and 77 females). Utilizing a probabilistic model called Bayesian network, this paper models the dependence structure between different emotions and negative behaviors of pilgrims in the crowd. The model included the following variables of emotion: negative, negative comfortable, positive, positive comfortable and positive spiritual and variables of negative behaviors; aggressive and hazardous acts. The study demonstrated that emotions of negative, negative comfortable, positive spiritual and positive emotion have a direct influence on aggressive behavior whereas emotion of negative comfortable, positive spiritual and positive have a direct influence on hazardous acts behavior. The sensitivity analysis showed that a low level of negative and negative comfortable emotions leads to a lower level of aggressive and hazardous behavior. Findings of the study can be further improved to identify the exact cause and risk factors of crowd-related incidents in preventing crowd disasters during the mass gathering events.

Flexible emotion-based decision-making behavior varies in current and former smokers.

Science.gov (United States)

Briggs, Zoe; O'Connor, Martin; Jollans, Emily K; O'Halloran, Laura; Dymond, Simon; Whelan, Robert

2015-06-01

Suboptimal decision-making is a feature in the initiation and maintenance of substance use, often manifested in choosing for short-term benefits rather than long-term gain, and the failure to display cognitive flexibility, respectively. Studies of nicotine users typically focus on characterizing those who are already addicted; less is known about decision-making in former smokers. Non- (n=21), former daily- (n=23) and current daily smokers (n=24), completed the contingency-shifting variant Iowa Gambling Task (csIGT), in which the reward and punishment contingencies of the decks are systematically varied after 100 trials of the 'standard' IGT. Scores on the standard blocks of the csIGT provided an index of emotion-based decision-making, while the contingency-shifting blocks assessed flexible decision-making. Subjective ratings were also recorded at 20-trial intervals. Both current and former smokers showed significantly impaired performance relative to non-smokers when making decisions during the standard blocks of the csIGT. Both former and non-smokers' awareness of the reward/punishment contingencies was significantly higher than those of current smokers at the end of the standard IGT. Both former and non-smokers had significantly better performance on the contingency shifting blocks, relative to current smokers. The findings indicate that both current and former smokers display a suboptimal pattern of decision-making than non-smokers during the standard IGT. However, with respect to the ability to change behavior following reversed contingencies, former smokers are more similar to non-smokers than to current smokers. Former smokers were also more aware of the contingencies than current smokers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Driving-forces model on individual behavior in scenarios considering moving threat agents

Science.gov (United States)

Li, Shuying; Zhuang, Jun; Shen, Shifei; Wang, Jia

2017-09-01

The individual behavior model is a contributory factor to improve the accuracy of agent-based simulation in different scenarios. However, few studies have considered moving threat agents, which often occur in terrorist attacks caused by attackers with close-range weapons (e.g., sword, stick). At the same time, many existing behavior models lack validation from cases or experiments. This paper builds a new individual behavior model based on seven behavioral hypotheses. The driving-forces model is an extension of the classical social force model considering scenarios including moving threat agents. An experiment was conducted to validate the key components of the model. Then the model is compared with an advanced Elliptical Specification II social force model, by calculating the fitting errors between the simulated and experimental trajectories, and being applied to simulate a specific circumstance. Our results show that the driving-forces model reduced the fitting error by an average of 33.9% and the standard deviation by an average of 44.5%, which indicates the accuracy and stability of the model in the studied situation. The new driving-forces model could be used to simulate individual behavior when analyzing the risk of specific scenarios using agent-based simulation methods, such as risk analysis of close-range terrorist attacks in public places.

Emotional or Behavioral Disorders: Background and Current Status of the E/BD Terminology and Definition.

Science.gov (United States)

Forness, Steven R.; Kavale, Kenneth A.

2000-01-01

This article reviews the development and current status of alternatives to the federal definition of emotional disturbance or behavior disorders. It notes that several states are now revising their own terminologies or definitions in response to the 1997 reauthorization of the Individuals with Disabilities Education Act that dropped the term…

Modeling of Tsunami Currents in Harbors

Science.gov (United States)

Lynett, P. J.

2010-12-01

Extreme events, such as large wind waves and tsunamis, are well recognized as a damaging hazard to port and harbor facilities. Wind wave events, particularly those with long period spectral components or infragravity wave generation, can excite resonance inside harbors leading to both large vertical motions and strong currents. Tsunamis can cause great damage as well. The geometric amplification of these very long waves can create large vertical motions in the interior of a harbor. Additionally, if the tsunami is composed of a train of long waves, which it often is, resonance can be easily excited. These long wave motions create strong currents near the node locations of resonant motions, and when interacting with harbor structures such as breakwaters, can create intense turbulent rotational structures, typical in the form of large eddies or gyres. These gyres have tremendous transport potential, and have been observed to break mooring lines, and even cause ships to be trapped inside the rotation, moving helplessly with the flow until collision, grounding, or dissipation of the eddy (e.g. Okal et al., 2006). This presentation will introduce the traditional theory used to predict wave impacts on harbors, discussing both how these models are practically useful and in what types of situations require a more accurate tool. State-of-the-art numerical models will be introduced, with a focus on recent developments in Boussinesq-type modeling. The Boussinesq equations model can account the dispersive, turbulent and rotational flow properties frequently observed in nature. Also they have the ability to coupling currents and waves and can predict nonlinear wave propagation over uneven bottom from deep (or intermediate) water area to shallow water area. However, during the derivation of a 2D-horizontal equation set, some 3D flow features, such those driven by as the dispersive stresses and the effects of the unresolved small scale 3D turbulence, are excluded. Consequently

A Method for Identification of the Equivalent Inductance and Resistance in the Plant Model of Current-Controlled Grid-Tied Converters

DEFF Research Database (Denmark)

Vidal, Ana; Yepes, Alejandro G.; Fernandez, Francisco Daniel Freijedo

2015-01-01

Precise knowledge of the plant time constant L=R is essential to perform a thorough analysis and design of the current control loop in voltage source converters (VSCs). From the perspective of the current controller dynamics in the low frequency range, such plant time constant is also suitable...... for most cases in which an LCL filter is used. As the loop behavior can be significantly influenced by the VSC working conditions, the effects associated to converter losses should be included in the model, through an equivalent series resistance. In addition, the plant inductance may also present...... important uncertainties with respect to the value of the VSC L/LCL interface filter measured at rated conditions. Thus, in this work, a method is presented to estimate both parameters of the plant time constant, i.e., the equivalent inductance and resistance in the plant model of current-controlled VSCs...

Behavioral testing in rodent models of orofacial neuropathic and inflammatory pain

Science.gov (United States)

Krzyzanowska, Agnieszka; Avendaño, Carlos

2012-01-01

Orofacial pain conditions are often very debilitating to the patient and difficult to treat. While clinical interest is high, the proportion of studies performed in the orofacial region in laboratory animals is relatively low, compared with other body regions. This is partly due to difficulties in testing freely moving animals and therefore lack of reliable testing methods. Here we present a comprehensive review of the currently used rodent models of inflammatory and neuropathic pain adapted to the orofacial areas, taking into account the difficulties and drawbacks of the existing approaches. We examine the available testing methods and procedures used for assessing the behavioral responses in the face in both mice and rats and provide a summary of some pharmacological agents used in these paradigms to date. The use of these agents in animal models is also compared with outcomes observed in the clinic. PMID:23139912

A Lookahead Behavior Model for Multi-Agent Hybrid Simulation

Directory of Open Access Journals (Sweden)

Mei Yang

2017-10-01

Full Text Available In the military field, multi-agent simulation (MAS plays an important role in studying wars statistically. For a military simulation system, which involves large-scale entities and generates a very large number of interactions during the runtime, the issue of how to improve the running efficiency is of great concern for researchers. Current solutions mainly use hybrid simulation to gain fewer updates and synchronizations, where some important continuous models are maintained implicitly to keep the system dynamics, and partial resynchronization (PR is chosen as the preferable state update mechanism. However, problems, such as resynchronization interval selection and cyclic dependency, remain unsolved in PR, which easily lead to low update efficiency and infinite looping of the state update process. To address these problems, this paper proposes a lookahead behavior model (LBM to implement a PR-based hybrid simulation. In LBM, a minimal safe time window is used to predict the interactions between implicit models, upon which the resynchronization interval can be efficiently determined. Moreover, the LBM gives an estimated state value in the lookahead process so as to break the state-dependent cycle. The simulation results show that, compared with traditional mechanisms, LBM requires fewer updates and synchronizations.

Transport simulations TFTR: Theoretically-based transport models and current scaling

International Nuclear Information System (INIS)

Redi, M.H.; Cummings, J.C.; Bush, C.E.; Fredrickson, E.; Grek, B.; Hahm, T.S.; Hill, K.W.; Johnson, D.W.; Mansfield, D.K.; Park, H.; Scott, S.D.; Stratton, B.C.; Synakowski, E.J.; Tang, W.M.; Taylor, G.

1991-12-01

In order to study the microscopic physics underlying observed L-mode current scaling, 1-1/2-d BALDUR has been used to simulate density and temperature profiles for high and low current, neutral beam heated discharges on TFTR with several semi-empirical, theoretically-based models previously compared for TFTR, including several versions of trapped electron drift wave driven transport. Experiments at TFTR, JET and D3-D show that I p scaling of τ E does not arise from edge modes as previously thought, and is most likely to arise from nonlocal processes or from the I p -dependence of local plasma core transport. Consistent with this, it is found that strong current scaling does not arise from any of several edge models of resistive ballooning. Simulations with the profile consistent drift wave model and with a new model for toroidal collisionless trapped electron mode core transport in a multimode formalism, lead to strong current scaling of τ E for the L-mode cases on TFTR. None of the theoretically-based models succeeded in simulating the measured temperature and density profiles for both high and low current experiments

A Neural Network Classifier Model for Forecasting Safety Behavior at Workplaces

Directory of Open Access Journals (Sweden)

Fakhradin Ghasemi

2017-07-01

Full Text Available The construction industry is notorious for having an unacceptable rate of fatal accidents. Unsafe behavior has been recognized as the main cause of most accidents occurring at workplaces, particularly construction sites. Having a predictive model of safety behavior can be helpful in preventing construction accidents. The aim of the present study was to build a predictive model of unsafe behavior using the Artificial Neural Network approach. A brief literature review was conducted on factors affecting safe behavior at workplaces and nine factors were selected to be included in the study. Data were gathered using a validated questionnaire from several construction sites. Multilayer perceptron approach was utilized for constructing the desired neural network. Several models with various architectures were tested to find the best one. Sensitivity analysis was conducted to find the most influential factors. The model with one hidden layer containing fourteen hidden neurons demonstrated the best performance (Sum of Squared Errors=6.73. The error rate of the model was approximately 21 percent. The results of sensitivity analysis showed that safety attitude, safety knowledge, supportive environment, and management commitment had the highest effects on safety behavior, while the effects from resource allocation and perceived work pressure were identified to be lower than those of others. The complex nature of human behavior at workplaces and the presence of many influential factors make it difficult to achieve a model with perfect performance.

Developing An Extended Theory Of Planned Behavior Model To Investigate Consumers Consumption Behavior Toward Organic Food A Case Study In Thailand

Directory of Open Access Journals (Sweden)

Kamonthip Maichum

2017-01-01

Full Text Available Organic foods are gaining popularity around the world and consumers of organic foods are on the rise. However information on the consumer behavior towards purchasing organic foods in developing countries such as Thailand is lacking. In this study we develop an extended theory of planned behavior TPB research model that incorporates organic knowledge to investigate consumers consumption intention and behavior towards organic food. We derived and examined the model through structural equation modeling SEM on a sample of 412 respondents in Thailand representing 82.40 of the samples that were investigated. Our findings indicated that consumer attitude and perceived behavioral control significantly predicts consumption intention whereas subjective norm does not. Hence consumption intention has a positive influence on organic food consumption behavior. Furthermore our results suggest that TPB model mediates the relationship between organic knowledge and consumption behavior.

Modeling pedestrian crossing speed profiles considering speed change behavior for the safety assessment of signalized intersections.

Science.gov (United States)

Iryo-Asano, Miho; Alhajyaseen, Wael K M

2017-11-01

Pedestrian safety is one of the most challenging issues in road networks. Understanding how pedestrians maneuver across an intersection is the key to applying countermeasures against traffic crashes. It is known that the behaviors of pedestrians at signalized crosswalks are significantly different from those in ordinary walking spaces, and they are highly influenced by signal indication, potential conflicts with vehicles, and intersection geometries. One of the most important characteristics of pedestrian behavior at crosswalks is the possible sudden speed change while crossing. Such sudden behavioral change may not be expected by conflicting vehicles, which may lead to hazardous situations. This study aims to quantitatively model the sudden speed changes of pedestrians as they cross signalized crosswalks under uncongested conditions. Pedestrian speed profiles are collected from empirical data and speed change events are extracted assuming that the speed profiles are stepwise functions. The occurrence of speed change events is described by a discrete choice model as a function of the necessary walking speed to complete crossing before the red interval ends, current speed, and the presence of turning vehicles in the conflict area. The amount of speed change before and after the event is modeled using regression analysis. A Monte Carlo simulation is applied for the entire speed profile of the pedestrians. The results show that the model can represent the pedestrian travel time distribution more accurately than the constant speed model. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular Dynamics Study of the Separation Behavior at the Interface between PVDF Binder and Copper Current Collector

Directory of Open Access Journals (Sweden)

Seungjun Lee

2016-01-01

Full Text Available In Li-ion batteries, the mechanical strengths at the interfaces of binder/particle and binder/current collector play an important role in maintaining the mechanical integrity of the composite electrode. In this work, the separation behaviors between polyvinylidene fluoride (PVDF binders and copper current collectors are studied in the opening and sliding modes using molecular dynamics (MD simulations. The simulation shows that the separation occurs inside the PVDF rather than at the interface due to the strong adhesion between PVDF and copper. This fracture behavior is different from the behavior of the PVDF/graphite basal plane that shows a clear separation at the interface. The results suggest that the adhesion strength of the PVDF/copper is stronger than that of the PVDF/graphite basal plane. The methodology used in MD simulation can directly evaluate the adhesion strength at the interfaces of various materials between binders, substrates, and particles at the atomic scales. The proposed method can therefore provide a guideline for the design of the electrode in order to enhance the mechanical integrity for better battery performance.

Evaluating system behavior through Dynamic Master Logic Diagram (DMLD) modeling

International Nuclear Information System (INIS)

Hu, Y.-S.; Modarres, Mohammad

1999-01-01

In this paper, the Dynamic Master Logic Diagram (DMLD) is introduced for representing full-scale time-dependent behavior and uncertain behavior of complex physical systems. Conceptually, the DMLD allows one to decompose a complex system hierarchically to model and to represent: (1) partial success/failure of the system, (2) full-scale logical, physical and fuzzy connectivity relations, (3) probabilistic, resolutional or linguistic uncertainty, (4) multiple-state system dynamics, and (5) floating threshold and transition effects. To demonstrate the technique, examples of using DMLD to model, to diagnose and to control dynamic behavior of a system are presented. A DMLD-based expert system building tool, called Dynamic Reliability Expert System (DREXs), is introduced to automate the DMLD modeling process

Using Difference Equation to Model Discrete-time Behavior in System Dynamics Modeling

NARCIS (Netherlands)

Hesan, R.; Ghorbani, A.; Dignum, M.V.

2014-01-01

In system dynamics modeling, differential equations have been used as the basic mathematical operator. Using difference equation to build system dynamics models instead of differential equation, can be insightful for studying small organizations or systems with micro behavior. In this paper we

Dynamic Socialized Gaussian Process Models for Human Behavior Prediction in a Health Social Network

Science.gov (United States)

Shen, Yelong; Phan, NhatHai; Xiao, Xiao; Jin, Ruoming; Sun, Junfeng; Piniewski, Brigitte; Kil, David; Dou, Dejing

2016-01-01

Modeling and predicting human behaviors, such as the level and intensity of physical activity, is a key to preventing the cascade of obesity and helping spread healthy behaviors in a social network. In our conference paper, we have developed a social influence model, named Socialized Gaussian Process (SGP), for socialized human behavior modeling. Instead of explicitly modeling social influence as individuals' behaviors influenced by their friends' previous behaviors, SGP models the dynamic social correlation as the result of social influence. The SGP model naturally incorporates personal behavior factor and social correlation factor (i.e., the homophily principle: Friends tend to perform similar behaviors) into a unified model. And it models the social influence factor (i.e., an individual's behavior can be affected by his/her friends) implicitly in dynamic social correlation schemes. The detailed experimental evaluation has shown the SGP model achieves better prediction accuracy compared with most of baseline methods. However, a Socialized Random Forest model may perform better at the beginning compared with the SGP model. One of the main reasons is the dynamic social correlation function is purely based on the users' sequential behaviors without considering other physical activity-related features. To address this issue, we further propose a novel “multi-feature SGP model” (mfSGP) which improves the SGP model by using multiple physical activity-related features in the dynamic social correlation learning. Extensive experimental results illustrate that the mfSGP model clearly outperforms all other models in terms of prediction accuracy and running time. PMID:27746515

Simulation of a model nanopore sensor: Ion competition underlies device behavior

Science.gov (United States)

Mádai, Eszter; Valiskó, Mónika; Dallos, András; Boda, Dezső

2017-12-01

We study a model nanopore sensor with which a very low concentration of analyte molecules can be detected on the basis of the selective binding of the analyte molecules to the binding sites on the pore wall. The bound analyte ions partially replace the current-carrier cations in a thermodynamic competition. This competition depends both on the properties of the nanopore and the concentrations of the competing ions (through their chemical potentials). The output signal given by the device is the current reduction caused by the presence of the analyte ions. The concentration of the analyte ions can be determined through calibration curves. We model the binding site with the square-well potential and the electrolyte as charged hard spheres in an implicit background solvent. We study the system with a hybrid method in which we compute the ion flux with the Nernst-Planck (NP) equation coupled with the Local Equilibrium Monte Carlo (LEMC) simulation technique. The resulting NP+LEMC method is able to handle both strong ionic correlations inside the pore (including finite size of ions) and bulk concentrations as low as micromolar. We analyze the effect of bulk ion concentrations, pore parameters, binding site parameters, electrolyte properties, and voltage on the behavior of the device.

Current algebra of classical non-linear sigma models

International Nuclear Information System (INIS)

Forger, M.; Laartz, J.; Schaeper, U.

1992-01-01

The current algebra of classical non-linear sigma models on arbitrary Riemannian manifolds is analyzed. It is found that introducing, in addition to the Noether current j μ associated with the global symmetry of the theory, a composite scalar field j, the algebra closes under Poisson brackets. (orig.)

Combined kinetic and transport modeling of radiofrequency current drive

International Nuclear Information System (INIS)

Dumont, R.; Giruzzi, G.; Barbato, E.

2000-07-01

A numerical model for predictive simulations of radiofrequency current drive in magnetically confined plasmas is developed. It includes the minimum requirements for a self consistent description of such regimes, i.e., a 3-D ,kinetic equation for the electron distribution function, 1-D heat and current transport equations, and resonant coupling between velocity space and configuration space dynamics, through suitable wave propagation equations. The model finds its full application in predictive studies of complex current profile control scenarios in tokamaks, aiming at the establishment of internal transport barriers by the simultaneous use of various radiofrequency current drive methods. The basic properties of this non-linear numerical system are investigated and illustrated by simulations applied to reversed magnetic shear regimes obtained by Lower Hybrid and Electron Cyclotron current drive for parameters typical of the Tore Supra tokamak. (authors)

Harmonic current prediction by impedance modeling of grid-tied inverters

DEFF Research Database (Denmark)

Pereira, Heverton A.; Freijedo, Francisco D.; Silva, M. M.

2017-01-01

and harmonic voltage profiles. Results reinforce that impedance models can represent with relatively accuracy the harmonic current emitted by the PV plants at the point of common coupling (PCC). Lastly, a stress test is performed to show how a variation in the harmonic voltage phase angle impacts the PV plant...... impedance models when used in harmonic integration studies. It is aimed to estimate the harmonic current contribution as a function of the background harmonic voltages components. Time domain simulations based on detailed and average models are compared with the impedance model developed in frequency domain....... In grids with harmonic voltages, impedance models can predict the current distortion for all active power injection scenarios. Furthermore, measurements in a 1.4 MW PV plant connected in a distributed grid are used to validate the simulation based on impedance models during different power injections...

Third Wave of Cognitive Behavioral Therapies

Directory of Open Access Journals (Sweden)

Sevginar Vatan

Full Text Available The psychological functioning of an individual includes well-being, cognitions, emotions and behaviors as a whole. In the current models of psychopathologies, as similar to well-being, reciprocal interaction between emotions, behaviors and cognitions is emphasized. Notwithstanding that the effects of these three components on cognitive behavior therapies can be mentioned too, it can be claimed that emotions were remained in the background by the behaviors and cognitions until the third wave of cognitive behavior therapies. Emotions have became prominent with the third wave approaches in the field of cognitive behavior therapy. In this review article, similarities and differences of third wave of cognitive behavior therapy with other waves, the constructs of emotion and emotion regulation in the third wave and the impacts of these on treatment were included. Additionally, throughout this perspective, treatment processes focusing on emotion regulation skills were discussed. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(3.000: 190-203

Applying incentive sensitization models to behavioral addiction

DEFF Research Database (Denmark)

Rømer Thomsen, Kristine; Fjorback, Lone; Møller, Arne

2014-01-01

The incentive sensitization theory is a promising model for understanding the mechanisms underlying drug addiction, and has received support in animal and human studies. So far the theory has not been applied to the case of behavioral addictions like Gambling Disorder, despite sharing clinical...... symptoms and underlying neurobiology. We examine the relevance of this theory for Gambling Disorder and point to predictions for future studies. The theory promises a significant contribution to the understanding of behavioral addiction and opens new avenues for treatment....

Does what you know matter? Investigating the relationship between mental models of climate change and pro-environmental behaviors

Science.gov (United States)

Davis, R.

2013-12-01

The purpose of this study is to test the conjecture that environmentally sustainable decisions and behaviors are related to individuals' conceptions of the natural world, in this case climate change; individuals' attitudes towards climate change; and the situations in which these decisions are made. The nature of mental models is an ongoing subject of disagreement. Some argue that mental models are coherent theories, much like scientific theories, that individuals employ systematically when reasoning about the world (Gopnik & Meltzoff, 1998). Others maintain that mental models are cobbled together from fragmented collections of ideas that are only loosely connected and context dependent (Disessa, 1988; Minstrell, 2000). It is likely that individuals sometimes reason about complex phenomena using systematic mental models and at other times reason using knowledge that is organized in fragmented pieces (Steedle & Shavelson, 2009). Thus, in measuring mental models of complex environmental systems, such as climate change, the assumption of systematicity may not be justified. Individuals may apply certain chains of reasoning in some contexts but not in others. The current study hypothesizes that an accurate mental model of climate change enables an individual to make effective evaluative judgments of environmental behavior options. The more an individual's mental model resembles that of an expert, the more consistent, accurate and automatic these judgments become. However, an accurate mental model is not sufficient to change environmental behavior. Real decisions and behaviors are products of a person-situation interaction: an interplay between psychosocial factors (such as knowledge and attitudes) and the situation in which the decision is made. This study investigates the relationship between both psychosocial and situational factors for climate change decisions. Data was collected from 436 adult participants through an online survey. The survey was comprised of

Current State of the Art Historic Building Information Modelling

Science.gov (United States)

Dore, C.; Murphy, M.

2017-08-01

In an extensive review of existing literature a number of observations were made in relation to the current approaches for recording and modelling existing buildings and environments: Data collection and pre-processing techniques are becoming increasingly automated to allow for near real-time data capture and fast processing of this data for later modelling applications. Current BIM software is almost completely focused on new buildings and has very limited tools and pre-defined libraries for modelling existing and historic buildings. The development of reusable parametric library objects for existing and historic buildings supports modelling with high levels of detail while decreasing the modelling time. Mapping these parametric objects to survey data, however, is still a time-consuming task that requires further research. Promising developments have been made towards automatic object recognition and feature extraction from point clouds for as-built BIM. However, results are currently limited to simple and planar features. Further work is required for automatic accurate and reliable reconstruction of complex geometries from point cloud data. Procedural modelling can provide an automated solution for generating 3D geometries but lacks the detail and accuracy required for most as-built applications in AEC and heritage fields.

Static current-sheet models of quiescent prominences

Science.gov (United States)

Wu, F.; Low, B. C.

1986-12-01

A particular class of theoretical models idealize the prominence to be a discrete flat electric-current sheet suspended vertically in a potential magnetic field. The weight of the prominence is supported by the Lorentz force in the current sheet. These models can be extended to have curved electric-current sheets and to vary three-dimensionally. The equation for force balance is 1 over 4 pi (del times B) times Bdel p- p9 z=zero. Using Cartesian coordinates we take, for simplicity, a uniform gravity with constant acceleration g in the direction -z. If we are interested not in the detailed internal structure of the prominence, but in the global magnetic configuration around the prominence, we may take prominence plasma to be cold. Consideration is given to how such equilibrium states can be constructed. To simplify the mathematical problem, suppose there is no electric current in the atmosphere except for the discrete currents in the cold prominence sheet. Let us take the plane z =0 to be the base of the atmosphere and restrict our attention to the domain z greater than 0. The task we have is to solve for a magnetic field which is everywhere potential except on some free surface S, subject to suit able to boundary conditions. The surface S is determined by requiring that it possesses a discrete electric current density such that the Lorentz force on it is everywhere vertically upward to balance the weight of the material m(S). Since the magnetic field is potential in the external atmosphere, the latter is decoupled from the magnetic field and its plane parallel hydrostatic pressure and density can be prescribed.

Effects of pulse current stimulation on the thermal fatigue crack propagation behavior of CHWD steel

International Nuclear Information System (INIS)

Lin, H.Q.; Zhao, Y.G.; Gao, Z.M.; Han, L.G.

2008-01-01

The fatigue crack propagating behaviors of cast hot working die (CHWD) steel untreated and treated by an electric current in the intermediate stage of thermal fatigue were investigated in the present study. The circle/elliptical heating affected zone (HAZ) was formed ahead of the notch tip on the fatigued specimens after pulse electric current stimulation. Both SEM observation and X-ray diffraction analysis revealed that pulse electric current stimulation refined grains/subgrains in the HAZs. With the prolonging of discharging duration, the grains/subgrains decreased in size and the dislocation density and microhardness increased gradually. The grain refinement and dislocation density increase played an important role in the material strengthening, which inevitably enhanced the propagation resistance and delayed the propagation of thermal fatigue cracks. Therefore, the pulse electric current stimulation was an effective method to improve the service lifetime of die material

Intervention Strategies Based on Information-Motivation-Behavioral Skills Model for Health Behavior Change: A Systematic Review

OpenAIRE

Chang, Sun Ju; Choi, Suyoung; Kim, Se-An; Song, Misoon

2014-01-01

Purpose: This study systematically reviewed research on behavioral interventions based on the information-motivation-behavioral skills (IMB) model to investigate specific intervention strategies that focus on information, motivation, and behavioral skills and to evaluate their effectiveness for people with chronic diseases. Methods: A systematic review was conducted in accordance with the guidelines of both the National Evidence-based Healthcare Collaborating Agency and Im and Chang. A lit...

A Behavioral Decision Making Modeling Approach Towards Hedging Services

NARCIS (Netherlands)

Pennings, J.M.E.; Candel, M.J.J.M.; Egelkraut, T.M.

2003-01-01

This paper takes a behavioral approach toward the market for hedging services. A behavioral decision-making model is developed that provides insight into how and why owner-managers decide the way they do regarding hedging services. Insight into those choice processes reveals information needed by

Agent-based modeling of sustainable behaviors

CERN Document Server

Sánchez-Maroño, Noelia; Fontenla-Romero, Oscar; Polhill, J; Craig, Tony; Bajo, Javier; Corchado, Juan

2017-01-01

Using the O.D.D. (Overview, Design concepts, Detail) protocol, this title explores the role of agent-based modeling in predicting the feasibility of various approaches to sustainability. The chapters incorporated in this volume consist of real case studies to illustrate the utility of agent-based modeling and complexity theory in discovering a path to more efficient and sustainable lifestyles. The topics covered within include: households' attitudes toward recycling, designing decision trees for representing sustainable behaviors, negotiation-based parking allocation, auction-based traffic signal control, and others. This selection of papers will be of interest to social scientists who wish to learn more about agent-based modeling as well as experts in the field of agent-based modeling.

Using Avatars to Model Weight Loss Behaviors: Participant Attitudes and Technology Development

Science.gov (United States)

Napolitano, Melissa A.; Hayes, Sharon; Russo, Giuseppe; Muresu, Debora; Giordano, Antonio; Foster, Gary D.

2013-01-01

Background: Virtual reality and other avatar-based technologies are potential methods for demonstrating and modeling weight loss behaviors. This study examined avatar-based technology as a tool for modeling weight loss behaviors. Methods: This study consisted of two phases: (1) an online survey to obtain feedback about using avatars for modeling weight loss behaviors and (2) technology development and usability testing to create an avatar-based technology program for modeling weight loss behaviors. Results: Results of phase 1 (n = 128) revealed that interest was high, with 88.3% stating that they would participate in a program that used an avatar to help practice weight loss skills in a virtual environment. In phase 2, avatars and modules to model weight loss skills were developed. Eight women were recruited to participate in a 4-week usability test, with 100% reporting they would recommend the program and that it influenced their diet/exercise behavior. Most women (87.5%) indicated that the virtual models were helpful. After 4 weeks, average weight loss was 1.6 kg (standard deviation = 1.7). Conclusion: This investigation revealed a high level of interest in an avatar-based program, with formative work indicating promise. Given the high costs associated with in vivo exposure and practice, this study demonstrates the potential use of avatar-based technology as a tool for modeling weight loss behaviors. PMID:23911189

Ritualistic chewing behavior induced by mCPP in the rat is an animal model of obsessive compulsive disorder.

Science.gov (United States)

Kreiss, Deborah S; Coffman, Catherine F; Fiacco, Nicholas R; Granger, Jason C; Helton, Bernadette M; Jackson, Jennifer C; Kim, Leonid V; Mistry, Rishi S; Mizer, Tammie M; Palmer, Lolita V; Vacca, Jay A; Winkler, Stuart S; Zimmer, Benjamin A

2013-03-01

Obsessive Compulsive Disorder (OCD) is characterized by recurrent, anxiety-producing thoughts accompanied by unwanted, overwhelming urges to perform ritualistic behaviors. Pharmacological treatments for this disorder (serotonin uptake inhibitors) are problematic because there is a 6-8 week delayed onset and half of the patients do not adequately respond. The present study evaluated whether Ritualistic Chewing Behaviors (RCBs) induced by the serotonin agonist mCPP in the rat is a behavioral model for OCD. The effects upon the RCBs induced by mCPP (1 mg/kg) were evaluated following treatments with either the serotonin antagonist mianserin (3 mg/kg), the dopamine antagonist haloperidol (1 mg/kg), the GABA modulator diazepam (10 mg/kg), or the serotonin uptake inhibitors clomipramine and fluvoxamine (15 mg/kg). The response to mCPP was blocked by acute treatment with mianserin, but not with acute haloperidol or diazepam. Further experiments revealed that the effects of mCPP were blocked by chronic, but not acute, treatment with clomipramine and fluvoxamine. A time-course demonstrated that 14 days of chronic treatment were required for blockade of the mCPP-evoked response. The current study demonstrates that mCPP-evoked RCBs may be a rodent model for OCD that can be used to predict the clinical efficacy and time course of novel OCD treatment. Future investigations may be able to use the current model as a tool for bench-marking corresponding changes in other measures of neurological activity that may provide insight into the mechanisms underlying OCD. Copyright © 2013. Published by Elsevier Inc.

Modeling of Lightning Strokes Using Two-Peaked Channel-Base Currents

Directory of Open Access Journals (Sweden)

V. Javor

2012-01-01

Full Text Available Lightning electromagnetic field is obtained by using “engineering” models of lightning return strokes and new channel-base current functions and the results are presented in this paper. Experimentally measured channel-base currents are approximated not only with functions having two-peaked waveshapes but also with the one-peaked function so as usually used in the literature. These functions are simple to be applied in any “engineering” or electromagnetic model as well. For the three “engineering” models: transmission line model (without the peak current decay, transmission line model with linear decay, and transmission line model with exponential decay with height, the comparison of electric and magnetic field components at different distances from the lightning channel-base is presented in the case of a perfectly conducting ground. Different heights of lightning channels are also considered. These results enable analysis of advantages/shortages of the used return stroke models according to the electromagnetic field features to be achieved, as obtained by measurements.

One-Dimensional Modelling of Marine Current Turbine Runaway Behaviour

Directory of Open Access Journals (Sweden)

Staffan Lundin

2016-04-01

Full Text Available If a turbine loses its electrical load, it will rotate freely and increase speed, eventually achieving that rotational speed which produces zero net torque. This is known as a runaway situation. Unlike many other types of turbine, a marine current turbine will typically overshoot the final runaway speed before slowing down and settling at the runaway speed. Since the hydrodynamic forces acting on the turbine are dependent on rotational speed and acceleration, turbine behaviour during runaway becomes important for load analyses during turbine design. In this article, we consider analytical and numerical models of marine current turbine runaway behaviour in one dimension. The analytical model is found not to capture the overshoot phenomenon, while still providing useful estimates of acceleration at the onset of runaway. The numerical model incorporates turbine wake build-up and predicts a rotational speed overshoot. The predictions of the models are compared against measurements of runaway of a marine current turbine. The models are also used to recreate previously-published results for a tidal turbine and applied to a wind turbine. It is found that both models provide reasonable estimates of maximum accelerations. The numerical model is found to capture the speed overshoot well.

Modeling landowner behavior regarding forest certification

Science.gov (United States)

David C. Mercker; Donald G. Hodges

2008-01-01

Nonindustrial private forest owners in western Tennessee were surveyed to assess their awareness, acceptance, and perceived benefits of forest certification. More than 80 percent of the landowners indicated a willingness to consider certification for their lands. A model was created to explain landowner behavior regarding their willingness to consider certification....

PERCEPTION AND BEHAVIOR ANALYSIS OF COMMUNITY TO THE EXISTENCE OF POIGAR PFMU MODEL

Directory of Open Access Journals (Sweden)

Arif Irawan

2017-04-01

Full Text Available Implementation of community empowerment scheme in the Poigar Production Forest Management Unit (PFMU Model area needs to take into account on community perception and behavior. This study aimed to determine the level of perception and behavior of the community towards the existence Poigar PFMU Model and to recommend the appropriate community empowerment scheme. To find out the perceptios and behavior of the Lolan Village community towards Poigar PFMU Model was by using Likert Scale. Furthermore, to determine the factors that influence people's behavior, then Spearman rank (Rs correlation test was used. The results showed that the level of perception of Lolan village communities to the existence of the Poigar PFMU Model was in good category, while the society behavior was in the less category. A good public perception of the Poigar PFMU Model area, did not have significant influence on its behavior. Community social characteristics that correlate with the behavior of the community were among others: education, level of income sourced from outside the area and level of interaction with the forest. Based on this, community empowerment strategy that is most likely to do in Poigar PFMU Model is through the Forestry Partnership Scheme.

Mathematical models of human behavior

DEFF Research Database (Denmark)

Møllgaard, Anders Edsberg

at the Technical University of Denmark. The data set includes face-to-face interaction (Bluetooth), communication (calls and texts), mobility (GPS), social network (Facebook), and general background information including a psychological profile (questionnaire). This thesis presents my work on the Social Fabric...... data set, along with work on other behavioral data. The overall goal is to contribute to a quantitative understanding of human behavior using big data and mathematical models. Central to the thesis is the determination of the predictability of different human activities. Upper limits are derived....... Evidence is provided, which implies that the asymmetry is caused by a self-enhancement in the initiation dynamics. These results have implications for the formation of social networks and the dynamics of the links. It is shown that the Big Five Inventory (BFI) representing a psychological profile only...

Nonlinear current-voltage behavior in PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Xiao, Mi; Zhang, Weikang; Zhang, Zebin; Li, Shida; Zhang, Ping; Lan, Kuibo [Tianjin University, School of Electrical and Information Engineering, Tianjin (China)

2017-05-15

In this paper, Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} (PZT) thin films were prepared by sol-gel synthesis and characterized by X-ray diffraction, field emission scanning electron microscopy and current-voltage measurements. Here, we demonstrate that in addition to the outstanding ferroelectric and dielectric properties, the PZT films also have remarkably nonlinear current-voltage characteristics. Considering the contact of semi-conductive grains in the PZT films, a double Schottky barrier (DSB) model may be responsible for such phenomena. The test results show that with the decrease of annealing temperature and the increase of the film thickness, the threshold voltages (V{sub th}) increase obviously. The maximum V{sub th} value of 60.95 V and the minimum value of 6.9 V in our experiments were obtained from the five-layered samples annealed at 600 C and the two-layered samples annealed at 700 C, respectively. As a result, PZT thin film may lead to efficient switching and sensing devices. (orig.)

Modeling of surface stress effects on bending behavior of nanowires: Incremental deformation theory

International Nuclear Information System (INIS)

Song, F.; Huang, G.L.

2009-01-01

The surface stress effects on bending behavior of nanowires have recently attracted a lot of attention. In this letter, the incremental deformation theory is first applied to study the surface stress effects upon the bending behavior of the nanowires. Different from other linear continuum approaches, the local geometrical nonlinearity of the Lagrangian strain is considered, therefore, the contribution of the surface stresses is naturally derived by applying the Hamilton's principle, and influence of the surface stresses along all surfaces of the nanowires is captured. It is first shown that the surface stresses along all surfaces have contribution not only on the effective Young's modulus of the nanowires but also on the loading term in the governing equation. The predictions of the effective Young's modulus and the resonance shift of the nanowires from the current method are compared with those from the experimental measurement and other existing approaches. The difference with other models is discussed. Finally, based on the current theory, the resonant shift predictions by using both the modified Euler-Bernoulli beam and the modified Timoshenko beam theories of the nanowires are investigated and compared. It is noticed that the higher vibration modes are less sensitive to the surface stresses than the lower vibration modes.

Social cognitive model of career self-management: toward a unifying view of adaptive career behavior across the life span.

Science.gov (United States)

Lent, Robert W; Brown, Steven D

2013-10-01

Social cognitive career theory (SCCT) currently consists of 4 overlapping, segmental models aimed at understanding educational and occupational interest development, choice-making, performance and persistence, and satisfaction/well-being. To this point, the theory has emphasized content aspects of career behavior, for instance, prediction of the types of activities, school subjects, or career fields that form the basis for people's educational/vocational interests and choice paths. However, SCCT may also lend itself to study of many process aspects of career behavior, including such issues as how people manage normative tasks and cope with the myriad challenges involved in career preparation, entry, adjustment, and change, regardless of the specific educational and occupational fields they inhabit. Such a process focus can augment and considerably expand the range of the dependent variables for which SCCT was initially designed. Building on SCCT's existing models, we present a social cognitive model of career self-management and offer examples of the adaptive, process behaviors to which it can be applied (e.g., career decision making/exploration, job searching, career advancement, negotiation of work transitions and multiple roles).

A spatial model of mosquito host-seeking behavior.

Directory of Open Access Journals (Sweden)

Bree Cummins

Full Text Available Mosquito host-seeking behavior and heterogeneity in host distribution are important factors in predicting the transmission dynamics of mosquito-borne infections such as dengue fever, malaria, chikungunya, and West Nile virus. We develop and analyze a new mathematical model to describe the effect of spatial heterogeneity on the contact rate between mosquito vectors and hosts. The model includes odor plumes generated by spatially distributed hosts, wind velocity, and mosquito behavior based on both the prevailing wind and the odor plume. On a spatial scale of meters and a time scale of minutes, we compare the effectiveness of different plume-finding and plume-tracking strategies that mosquitoes could use to locate a host. The results show that two different models of chemotaxis are capable of producing comparable results given appropriate parameter choices and that host finding is optimized by a strategy of flying across the wind until the odor plume is intercepted. We also assess the impact of changing the level of host aggregation on mosquito host-finding success near the end of the host-seeking flight. When clusters of hosts are more tightly associated on smaller patches, the odor plume is narrower and the biting rate per host is decreased. For two host groups of unequal number but equal spatial density, the biting rate per host is lower in the group with more individuals, indicative of an attack abatement effect of host aggregation. We discuss how this approach could assist parameter choices in compartmental models that do not explicitly model the spatial arrangement of individuals and how the model could address larger spatial scales and other probability models for mosquito behavior, such as Lévy distributions.

[Research on the behavior of fruit and vegetable intake in adolescents with Transtheoretical Model].

Science.gov (United States)

Mao, Chen-Jia; Xu, Liang-Wen; Qu, Xu-Ping; Yang, Qi-Fa; Hu, Han-Qiong; Xu, Dong-Ming

2010-05-01

To study the current situation and factors influencing the behavior of fruit and vegetable intake in adolescents, and to discuss health education strategy related to the behavior. 1677 students were selected from primary school and middle school in urban area of Hangzhou by a multistage sampling method. The behavior of fruit and vegetable intake was surveyed by questionnaires of the patient-centered assessment and counseling for exercise plus nutrition project (PACE+) for adolescent-scale of fruit and vegetable consumption, and analyzed by Transtheoretical Model on the servings of intake, the stage of change, process of change, decisional balance and the current status of self-efficacy. The average intake of fruit and vegetable in adolescents was (3.21 +/- 1.50) servings per day ("one serving" means 100 g cooked vegetable or 100 g fruit). The behavior of consuming fruit and vegetable in most of the adolescents was in the contemplation stage, accounting for 36.91% (619/1677). The process of behavior change, decisional balance (Pros) and self-efficacy existed a positive correlation with the process of stage (r(process) = 0.38, r(decisional balance (Pros)) = 0.26, r(self-efficacy) = 0.33, t values were 16.78, 11.02 and 14.31, P < 0.05). The servings of fruit and vegetable intake existed a positive correlation with stage transition and self-efficacy (beta(stage transition) = 0.665, t = 35.07, P < 0.05; beta(self-efficacy) = 0.050, t = 2.63, P < 0.05), and existed a negative correlation with decisional balance (Cons) (beta(decisional balance (Cons)) = -0.051, t = -2.84, P < 0.05). Fruit and vegetable intake of these adolescents are under the recommended dietary intake. Along with behavior stage development and self-efficacy improvement, the intake of fruit and vegetable also increased correspondingly. Intervention strategies should aim at improving the awareness of adolescents on the health benefits of fruit and vegetable intake and promoting their confidence to reach

Current density distribution during disruptions and sawteeth in a simple model of plasma current in a tokamak

International Nuclear Information System (INIS)

Stefanovskii, A. M.

2011-01-01

The processes that are likely to accompany discharge disruptions and sawteeth in a tokamak are considered in a simple plasma current model. The redistribution of the current density in plasma is supposed to be primarily governed by the onset of the MHD-instability-driven turbulent plasma mixing in a finite region of the current column. For different disruption conditions, the variation in the total plasma current (the appearance of a characteristic spike) is also calculated. It is found that the numerical shape and amplitude of the total current spikes during disruptions approximately coincide with those measured in some tokamak experiments. Under the assumptions adopted in the model, the physical mechanism for the formation of the spikes is determined. The mechanism is attributed to the diffusion of the negative current density at the column edge into the zero-conductivity region. The numerical current density distributions in the plasma during the sawteeth differ from the literature data.

Sex-Related Online Behaviors, Perceived Peer Norms and Adolescents’ Experience with Sexual Behavior: Testing an Integrative Model

Science.gov (United States)

Doornwaard, Suzan M.; ter Bogt, Tom F. M.; Reitz, Ellen; van den Eijnden, Regina J. J. M.

2015-01-01

Research on the role of sex-related Internet use in adolescents’ sexual development has often isolated the Internet and online behaviors from other, offline influencing factors in adolescents’ lives, such as processes in the peer domain. The aim of this study was to test an integrative model explaining how receptive (i.e., use of sexually explicit Internet material [SEIM]) and interactive (i.e., use of social networking sites [SNS]) sex-related online behaviors interrelate with perceived peer norms in predicting adolescents’ experience with sexual behavior. Structural equation modeling on longitudinal data from 1,132 Dutch adolescents (Mage T1 = 13.95; range 11-17; 52.7% boys) demonstrated concurrent, direct, and indirect effects between sex-related online behaviors, perceived peer norms, and experience with sexual behavior. SEIM use (among boys) and SNS use (among boys and girls) predicted increases in adolescents’ perceptions of peer approval of sexual behavior and/or in their estimates of the numbers of sexually active peers. These perceptions, in turn, predicted increases in adolescents’ level of experience with sexual behavior at the end of the study. Boys’ SNS use also directly predicted increased levels of experience with sexual behavior. These findings highlight the need for multisystemic research and intervention development to promote adolescents’ sexual health. PMID:26086606

A Model-Based Approach to Engineering Behavior of Complex Aerospace Systems

Science.gov (United States)

Ingham, Michel; Day, John; Donahue, Kenneth; Kadesch, Alex; Kennedy, Andrew; Khan, Mohammed Omair; Post, Ethan; Standley, Shaun

2012-01-01

One of the most challenging yet poorly defined aspects of engineering a complex aerospace system is behavior engineering, including definition, specification, design, implementation, and verification and validation of the system's behaviors. This is especially true for behaviors of highly autonomous and intelligent systems. Behavior engineering is more of an art than a science. As a process it is generally ad-hoc, poorly specified, and inconsistently applied from one project to the next. It uses largely informal representations, and results in system behavior being documented in a wide variety of disparate documents. To address this problem, JPL has undertaken a pilot project to apply its institutional capabilities in Model-Based Systems Engineering to the challenge of specifying complex spacecraft system behavior. This paper describes the results of the work in progress on this project. In particular, we discuss our approach to modeling spacecraft behavior including 1) requirements and design flowdown from system-level to subsystem-level, 2) patterns for behavior decomposition, 3) allocation of behaviors to physical elements in the system, and 4) patterns for capturing V&V activities associated with behavioral requirements. We provide examples of interesting behavior specification patterns, and discuss findings from the pilot project.

Modeling the thermotaxis behavior of C.elegans based on the artificial neural network.

Science.gov (United States)

Li, Mingxu; Deng, Xin; Wang, Jin; Chen, Qiaosong; Tang, Yun

2016-07-03

ASBTRACT This research aims at modeling the thermotaxis behavior of C.elegans which is a kind of nematode with full clarified neuronal connections. Firstly, this work establishes the motion model which can perform the undulatory locomotion with turning behavior. Secondly, the thermotaxis behavior is modeled by nonlinear functions and the nonlinear functions are learned by artificial neural network. Once the artificial neural networks have been well trained, they can perform the desired thermotaxis behavior. Last, several testing simulations are carried out to verify the effectiveness of the model for thermotaxis behavior. This work also analyzes the different performances of the model under different environments. The testing results reveal the essence of the thermotaxis of C.elegans to some extent, and theoretically support the research on the navigation of the crawling robots.

An extension of the theory of planned behavior to predict pedestrians' violating crossing behavior using structural equation modeling.

Science.gov (United States)

Zhou, Hongmei; Romero, Stephanie Ballon; Qin, Xiao

2016-10-01

This paper aimed to examine pedestrians' self-reported violating crossing behavior intentions by applying the theory of planned behavior (TPB). We studied the behavior intentions regarding instrumental attitude, subjective norm, perceived behavioral control, the three basic components of TPB, and extended the theory by adding new factors including descriptive norm, perceived risk and conformity tendency to evaluate their respective impacts on pedestrians' behavior intentions. A questionnaire presented with a scenario that pedestrians crossed the road violating the pedestrian lights at an intersection was designed, and the survey was conducted in Dalian, China. Based on the 260 complete and valid responses, reliability and validity of the data for each question was evaluated. The data were then analyzed by using the structural equation modeling (SEM). The results showed that people had a negative attitude toward the behavior of violating road-crossing rules; they perceived social influences from their family and friends; and they believed that this kind of risky behavior would potentially harm them in a traffic accident. The results also showed that instrumental attitude and subjective norm were significant in the basic TPB model. After adding descriptive norm, subjective norm was no more significant. Other models showed that conformity tendency was a strong predictor, indicating that the presence of other pedestrians would influence behavioral intention. The findings could help to design more effective interventions and safety campaigns, such as changing people's attitude toward this violation behavior, correcting the social norms, increasing their safety awareness, etc. in order to reduce pedestrians' road crossing violations. Copyright © 2015 Elsevier Ltd. All rights reserved.

A conceptual model of nurses' goal orientation, service behavior, and service performance.

Science.gov (United States)

Chien, Chun-Cheng; Chou, Hsin-Kai; Hung, Shuo-Tsung

2008-01-01

Based on the conceptual framework known as the "service triangle," the authors constructed a model of nurses' goal orientation, service behavior, and service performance to investigate the antecedents and consequences of the medical service behavior provided by nurses. This cross-sectional study collected data from 127 nurses in six hospitals using a mail-in questionnaire. Analysis of the model revealed that the customer-oriented behavior of nurses had a positive influence on organizational citizenship behavior; and both of these behaviors had a significant positive influence on service performance. The results also indicate that a higher learning goal orientation among nurses was associated with the performance of both observable customer-oriented behavior and organizational-citizenship behavior.

Modelling of current loads on aquaculture net cages

Science.gov (United States)

Kristiansen, Trygve; Faltinsen, Odd M.

2012-10-01

In this paper we propose and discuss a screen type of force model for the viscous hydrodynamic load on nets. The screen model assumes that the net is divided into a number of flat net panels, or screens. It may thus be applied to any kind of net geometry. In this paper we focus on circular net cages for fish farms. The net structure itself is modelled by an existing truss model. The net shape is solved for in a time-stepping procedure that involves solving a linear system of equations for the unknown tensions at each time step. We present comparisons to experiments with circular net cages in steady current, and discuss the sensitivity of the numerical results to a set of chosen parameters. Satisfactory agreement between experimental and numerical prediction of drag and lift as function of the solidity ratio of the net and the current velocity is documented.

Parental factors and adolescents' smoking behavior: an extension of The theory of planned behavior.

Science.gov (United States)

Harakeh, Zeena; Scholte, Ron H J; Vermulst, Ad A; de Vries, Hein; Engels, Rutger C M E

2004-11-01

The aim of the present study is to investigate whether general parenting factors (i.e., quality parent-child relationship, psychological control, strict control, parental knowledge) and parental smoking add to The theory of planned behaviour [Organ Behav. Hum. Dec. 50 (1991) 179] in predicting the onset of smoking. A mediation model is applied in which parental factors affect smoking behavior indirectly by affecting smoking cognitions (i.e., attitude, self-efficacy, and social norm). The model was tested in a longitudinal study on 1,070 adolescents, aged 10-14 years old. Structural equation models (SEM) on current and on future smoking behavior were tested. The findings showed that the quality of the parent-child relationship and parental knowledge affected adolescents' smoking behavior indirectly, while parental smoking behavior had a direct effect. Strict control and psychological control were found to be unrelated to adolescents' smoking onset. In prevention campaigns, parents should be informed of the extent to which they exert influence on their child's smoking behavior and should be given advice and information on how they can prevent their children from starting to smoke.

Modeling complicated rheological behaviors in encapsulating shells of lipid-coated microbubbles accounting for nonlinear changes of both shell viscosity and elasticity.

Science.gov (United States)

Li, Qian; Matula, Thomas J; Tu, Juan; Guo, Xiasheng; Zhang, Dong

2013-02-21

It has been accepted that the dynamic responses of ultrasound contrast agent (UCA) microbubbles will be significantly affected by the encapsulating shell properties (e.g., shell elasticity and viscosity). In this work, a new model is proposed to describe the complicated rheological behaviors in an encapsulating shell of UCA microbubbles by applying the nonlinear 'Cross law' to the shell viscous term in the Marmottant model. The proposed new model was verified by fitting the dynamic responses of UCAs measured with either a high-speed optical imaging system or a light scattering system. The comparison results between the measured radius-time curves and the numerical simulations demonstrate that the 'compression-only' behavior of UCAs can be successfully simulated with the new model. Then, the shell elastic and viscous coefficients of SonoVue microbubbles were evaluated based on the new model simulations, and compared to the results obtained from some existing UCA models. The results confirm the capability of the current model for reducing the dependence of bubble shell parameters on the initial bubble radius, which indicates that the current model might be more comprehensive to describe the complex rheological nature (e.g., 'shear-thinning' and 'strain-softening') in encapsulating shells of UCA microbubbles by taking into account the nonlinear changes of both shell elasticity and shell viscosity.

Modeling complicated rheological behaviors in encapsulating shells of lipid-coated microbubbles accounting for nonlinear changes of both shell viscosity and elasticity

International Nuclear Information System (INIS)

Li Qian; Tu Juan; Guo Xiasheng; Zhang Dong; Matula, Thomas J

2013-01-01

It has been accepted that the dynamic responses of ultrasound contrast agent (UCA) microbubbles will be significantly affected by the encapsulating shell properties (e.g., shell elasticity and viscosity). In this work, a new model is proposed to describe the complicated rheological behaviors in an encapsulating shell of UCA microbubbles by applying the nonlinear ‘Cross law’ to the shell viscous term in the Marmottant model. The proposed new model was verified by fitting the dynamic responses of UCAs measured with either a high-speed optical imaging system or a light scattering system. The comparison results between the measured radius–time curves and the numerical simulations demonstrate that the ‘compression-only’ behavior of UCAs can be successfully simulated with the new model. Then, the shell elastic and viscous coefficients of SonoVue microbubbles were evaluated based on the new model simulations, and compared to the results obtained from some existing UCA models. The results confirm the capability of the current model for reducing the dependence of bubble shell parameters on the initial bubble radius, which indicates that the current model might be more comprehensive to describe the complex rheological nature (e.g., ‘shear-thinning’ and ‘strain-softening’) in encapsulating shells of UCA microbubbles by taking into account the nonlinear changes of both shell elasticity and shell viscosity. (paper)

Dimensional structure of DSM-5 posttraumatic stress symptoms: support for a hybrid Anhedonia and Externalizing Behaviors model.

Science.gov (United States)

Armour, Cherie; Tsai, Jack; Durham, Tory A; Charak, Ruby; Biehn, Tracey L; Elhai, Jon D; Pietrzak, Robert H

2015-02-01

Several revisions to the symptom clusters of posttraumatic stress disorder (PTSD) have been made in the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Central to the focus of this study was the revision of PTSD's tripartite structure in DSM-IV into four symptom clusters in DSM-5. Emerging confirmatory factor analytic (CFA) studies have suggested that DSM-5 PTSD symptoms may be best represented by one of two 6-factor models: (1) an Externalizing Behaviors model characterized by a factor which combines the irritability/anger and self-destructive/reckless behavior items; and (2) an Anhedonia model characterized by items of loss of interest, detachment, and restricted affect. The current study conducted CFAs of DSM-5 PTSD symptoms assessed using the PTSD Checklist for DSM-5 (PCL-5) in two independent and diverse trauma-exposed samples of a nationally representative sample of 1484 U.S. veterans and a sample of 497 Midwestern U.S. university undergraduate students. Relative fits of the DSM-5 model, the DSM-5 Dysphoria model, the DSM-5 Dysphoric Arousal model, the two 6-factor models, and a newly proposed 7-factor Hybrid model, which consolidates the two 6-factor models, were evaluated. Results revealed that, in both samples, both 6-factor models provided significantly better fit than the 4-factor DSM-5 model, the DSM-5 Dysphoria model and the DSM-5 Dysphoric Arousal model. Further, the 7-factor Hybrid model, which incorporates key features of both 6-factor models and is comprised of re-experiencing, avoidance, negative affect, anhedonia, externalizing behaviors, and anxious and dysphoric arousal symptom clusters, provided superior fit to the data in both samples. Results are discussed in light of theoretical and empirical support for the latent structure of DSM-5 PTSD symptoms. Copyright © 2014 Elsevier Ltd. All rights reserved.