We present numerical simulations for an ABS resin extrusion in an industrial conventional single ... more We present numerical simulations for an ABS resin extrusion in an industrial conventional single screw extruder. Based upon the flow field patterns obtained in the simulations, a particle tracking procedure was employed to obtain information about the spatial distribution of particle tracers of two colors. Results of the simulation were compared with experimental data obtained under similar extrusion conditions. To evaluate the degree of color mixing and color homogeneity for the system, we employ a specific index calculated based upon the Shannon entropy for two species populations
W e report a spatial-memory scanning experiment that was used to measure age di erences in entrop... more W e report a spatial-memory scanning experiment that was used to measure age di erences in entropy. A target grid consisting of four adjacent letters followed by the presentation of a single probe letter was presented on each trial. Half of the trials presented the probe stimulus in the same spatial position was the target letter (i.e., the probe letter was always a member of the positive set), and half of the trails transposed the target letter one, two, or three spaces of the right or left of the original target display position (i.e., di erent trials). T he experiment involved blocks of primary-memory and secondary-memory tasks. Reaction-time and error-rate data, as well as entropy analyses and the tting of an entropy model (based on Allen, Kaufman, Smith, and Propper, in press) to the empirical data indicated that older adults showed higher entropy levels than young adults. T hese results are interpret ed in a ''computational temperature'' framework in which older adults' higher computational temperatures result in less efficient spatial, episodic memory functioning.
Rapidly increasing political polarization threatens democracies around the world. Scholars from s... more Rapidly increasing political polarization threatens democracies around the world. Scholars from several disciplines are assessing and modeling polarization antecedents, processes, and consequences. Social systems are complex and networked. Their constant shifting hinders attempts to trace causes of observed trends, predict their consequences, or mitigate them. We propose an equivalent-neighbor model of polarization dynamics. Using statistical physics techniques, we generate anticipatory scenarios and examine whether leadership and/or external events alleviate or exacerbate polarization. We consider three highly polarized USA groups: Democrats, Republicans, and Independents. We assume that in each group, each individual has a political stance s ranging between left and right. We quantify the noise in this system as a “social temperature” T. Using energy E, we describe individuals’ interactions in time within their own group and with individuals of the other groups. It depends on the ...
This interdisciplinary work examines the complex process of negotiating labor relations in genera... more This interdisciplinary work examines the complex process of negotiating labor relations in general and in the specific context of France. Drawing on social identity theory, we use a dynamic, multiplex network model to capture interactions between several groups of labor relations actors. At one multiplex level, union members interact with each other and with their representatives; at a second level, management negotiators interact with union negotiators. Government regulations and internal organizational factors form the negotiations context, which can affect the negotiation process and outcomes. We map multiple interactions in time under different contextual conditions—scenarios—enabling parties to explore various strategies and their expected results, and to develop ways to attain or avoid them. To illustrate the model’s potential, we focus here on a Major European Industrial company (MEI) active in four European countries (France, Great Britain, Germany, and Spain). We collect MEI-specific labor relations data through participatory observation and interviews at the French site. We estimate MEI-specific model parameters and generate scenarios of conflict trajectories and outcomes for this case under several contextual assumptions
Complex social-ecological systems—such as cities and regions—change in time whether or not we int... more Complex social-ecological systems—such as cities and regions—change in time whether or not we intervene through plans and policies. This is due in part to the numerous individual and organizational actors who make self-interested, unilateral decisions. Public decision makers are expected to act in the public interest and are accountable to constituents. They need the ability to explore alternatives, select ones that are likely to benefit the public, and avoid or mitigate negative outcomes. Predicting processes and outcomes in the context of complex systems is risky, however, and mistakes can be costly. Switching from prediction of specific future states to anticipation of possible ranges of futures may help contend with the uncertainties inherent in these systems. We propose here a dynamic network model for generating ranges of possible futures for employment location in an economic region. The model can be used to anticipate employment location effects of various policies. First, u...
Public policy and planning decisions require glimpses into the future, to assess how the social-e... more Public policy and planning decisions require glimpses into the future, to assess how the social-ecological systems we plan for might evolve with or without policy intervention. To do so, one approach gaining currency is using anticipatory tools rather than predictions. Anticipation entails generating a range of possible systems futures (scenarios), instead of attempting to predict the one that will prevail. We use here a scenario-generating model, to anticipate where in a region businesses are likely to locate in time. Using data for Northeast Ohio, including the Cleveland-Akron-Lorain-Elyria, Ohio Combined Statistical Area, we estimate the model parameters. We evaluate its prediction accuracy against 2001-2015 regional data. To illustrate how policymakers could use the model, we generate three scenarios to explore what might happen to the spatial configuration of businesses if policies were implemented to attract businesses at specific locations or discourage them from locating in parts of the region.
We study a statistical mechanics model of a solid. Neighboring atoms are connected by Hookian "sp... more We study a statistical mechanics model of a solid. Neighboring atoms are connected by Hookian "springs". If the energy of a "spring" is larger than a threshold, the "spring" is more likely to fail, while if the energy is lower than the threshold the spring is more likely to be alive. The phase diagram and thermodynamic quantities, free energy, numbers of bonds and clusters etc, are determined using renormalizationgroup and Monte-Carlo techniques.
For the q-state Potts model with 2 < q <= 4 on the square lattice with a defect line, the order p... more For the q-state Potts model with 2 < q <= 4 on the square lattice with a defect line, the order parameter on the defect line jumps discontinuously from zero to a nonzero value while the defect energy varies continuously with the temperature at the critical temperature. Monte-Carlo simulations (H. T. Diep, M. Kaufman, Phys Rev E 2009) of the q-state Potts model on a square lattice with a line of defects verify the renormalization group prediction (M. Kaufman, R. B. Griffiths, Phys Rev B 1982) on the occurrence of the hybrid transition on the defect line. This is interesting since for those q values the bulk transition is continuous. This hybrid (continuous-discontinuous) defect transition is induced by the infinite range correlations at the bulk critical point.
Procedures are developed for using cOlJlposition data in the three-phase region and variations of... more Procedures are developed for using cOlJlposition data in the three-phase region and variations of meniscus heights to determine the parameters needed to relate a classical thermodynamic model for fluid mixtures near tricritical points to actual experiments. In the case of the mixture ammonium sulfate + water + ethanol + benzene the result is a reasonably good fit to a variety of data, including light scattering measurements of intensity and correlation length. There is some evidence for deviations from the classical theory, but it is not unambiguous.
We present numerical simulations for an ABS resin extrusion in an industrial conventional single ... more We present numerical simulations for an ABS resin extrusion in an industrial conventional single screw extruder. Based upon the flow field patterns obtained in the simulations, a particle tracking procedure was employed to obtain information about the spatial distribution of particle tracers of two colors. Results of the simulation were compared with experimental data obtained under similar extrusion conditions. To evaluate the degree of color mixing and color homogeneity for the system, we employ a specific index calculated based upon the Shannon entropy for two species populations
W e report a spatial-memory scanning experiment that was used to measure age di erences in entrop... more W e report a spatial-memory scanning experiment that was used to measure age di erences in entropy. A target grid consisting of four adjacent letters followed by the presentation of a single probe letter was presented on each trial. Half of the trials presented the probe stimulus in the same spatial position was the target letter (i.e., the probe letter was always a member of the positive set), and half of the trails transposed the target letter one, two, or three spaces of the right or left of the original target display position (i.e., di erent trials). T he experiment involved blocks of primary-memory and secondary-memory tasks. Reaction-time and error-rate data, as well as entropy analyses and the tting of an entropy model (based on Allen, Kaufman, Smith, and Propper, in press) to the empirical data indicated that older adults showed higher entropy levels than young adults. T hese results are interpret ed in a ''computational temperature'' framework in which older adults' higher computational temperatures result in less efficient spatial, episodic memory functioning.
Rapidly increasing political polarization threatens democracies around the world. Scholars from s... more Rapidly increasing political polarization threatens democracies around the world. Scholars from several disciplines are assessing and modeling polarization antecedents, processes, and consequences. Social systems are complex and networked. Their constant shifting hinders attempts to trace causes of observed trends, predict their consequences, or mitigate them. We propose an equivalent-neighbor model of polarization dynamics. Using statistical physics techniques, we generate anticipatory scenarios and examine whether leadership and/or external events alleviate or exacerbate polarization. We consider three highly polarized USA groups: Democrats, Republicans, and Independents. We assume that in each group, each individual has a political stance s ranging between left and right. We quantify the noise in this system as a “social temperature” T. Using energy E, we describe individuals’ interactions in time within their own group and with individuals of the other groups. It depends on the ...
This interdisciplinary work examines the complex process of negotiating labor relations in genera... more This interdisciplinary work examines the complex process of negotiating labor relations in general and in the specific context of France. Drawing on social identity theory, we use a dynamic, multiplex network model to capture interactions between several groups of labor relations actors. At one multiplex level, union members interact with each other and with their representatives; at a second level, management negotiators interact with union negotiators. Government regulations and internal organizational factors form the negotiations context, which can affect the negotiation process and outcomes. We map multiple interactions in time under different contextual conditions—scenarios—enabling parties to explore various strategies and their expected results, and to develop ways to attain or avoid them. To illustrate the model’s potential, we focus here on a Major European Industrial company (MEI) active in four European countries (France, Great Britain, Germany, and Spain). We collect MEI-specific labor relations data through participatory observation and interviews at the French site. We estimate MEI-specific model parameters and generate scenarios of conflict trajectories and outcomes for this case under several contextual assumptions
Complex social-ecological systems—such as cities and regions—change in time whether or not we int... more Complex social-ecological systems—such as cities and regions—change in time whether or not we intervene through plans and policies. This is due in part to the numerous individual and organizational actors who make self-interested, unilateral decisions. Public decision makers are expected to act in the public interest and are accountable to constituents. They need the ability to explore alternatives, select ones that are likely to benefit the public, and avoid or mitigate negative outcomes. Predicting processes and outcomes in the context of complex systems is risky, however, and mistakes can be costly. Switching from prediction of specific future states to anticipation of possible ranges of futures may help contend with the uncertainties inherent in these systems. We propose here a dynamic network model for generating ranges of possible futures for employment location in an economic region. The model can be used to anticipate employment location effects of various policies. First, u...
Public policy and planning decisions require glimpses into the future, to assess how the social-e... more Public policy and planning decisions require glimpses into the future, to assess how the social-ecological systems we plan for might evolve with or without policy intervention. To do so, one approach gaining currency is using anticipatory tools rather than predictions. Anticipation entails generating a range of possible systems futures (scenarios), instead of attempting to predict the one that will prevail. We use here a scenario-generating model, to anticipate where in a region businesses are likely to locate in time. Using data for Northeast Ohio, including the Cleveland-Akron-Lorain-Elyria, Ohio Combined Statistical Area, we estimate the model parameters. We evaluate its prediction accuracy against 2001-2015 regional data. To illustrate how policymakers could use the model, we generate three scenarios to explore what might happen to the spatial configuration of businesses if policies were implemented to attract businesses at specific locations or discourage them from locating in parts of the region.
We study a statistical mechanics model of a solid. Neighboring atoms are connected by Hookian "sp... more We study a statistical mechanics model of a solid. Neighboring atoms are connected by Hookian "springs". If the energy of a "spring" is larger than a threshold, the "spring" is more likely to fail, while if the energy is lower than the threshold the spring is more likely to be alive. The phase diagram and thermodynamic quantities, free energy, numbers of bonds and clusters etc, are determined using renormalizationgroup and Monte-Carlo techniques.
For the q-state Potts model with 2 < q <= 4 on the square lattice with a defect line, the order p... more For the q-state Potts model with 2 < q <= 4 on the square lattice with a defect line, the order parameter on the defect line jumps discontinuously from zero to a nonzero value while the defect energy varies continuously with the temperature at the critical temperature. Monte-Carlo simulations (H. T. Diep, M. Kaufman, Phys Rev E 2009) of the q-state Potts model on a square lattice with a line of defects verify the renormalization group prediction (M. Kaufman, R. B. Griffiths, Phys Rev B 1982) on the occurrence of the hybrid transition on the defect line. This is interesting since for those q values the bulk transition is continuous. This hybrid (continuous-discontinuous) defect transition is induced by the infinite range correlations at the bulk critical point.
Procedures are developed for using cOlJlposition data in the three-phase region and variations of... more Procedures are developed for using cOlJlposition data in the three-phase region and variations of meniscus heights to determine the parameters needed to relate a classical thermodynamic model for fluid mixtures near tricritical points to actual experiments. In the case of the mixture ammonium sulfate + water + ethanol + benzene the result is a reasonably good fit to a variety of data, including light scattering measurements of intensity and correlation length. There is some evidence for deviations from the classical theory, but it is not unambiguous.
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