Logical Modeling of Adiabatic Logic Circuits Using VHDL

The underlying nature of adiabatic circuits is most accurately characterized at the circuit level as it is for traditional technologies. In order to scale system designs for adiabatic logic technologies, modeling of adiabatic circuits at the logic level is necessary. Logic level models of adiabatic logic circuits can facilitate the design, development, and verification of large scale digital systems that may be infeasible using circuit simulators. Adiabatic logic circuits can be powered with a four stage power clock consisting of idle, charge, hold, and recover stages that provides for adiabatic charging and charge recovery to give adiabatic circuits their low power operation. By both discretizing the temporal aspects of the power clock and the logic values, a logical model of adiabatic circuit operation is proposed. Using the expressive capabilities of Very High Speed Integrated Circuit (VHSIC) Hardware Description Language (VHDL), the salient aspects of adiabatic circuit models can be captured. In this work, a VHDL framework is defined for modeling adiabatic logic circuits & systems and its use is demonstrated in several example adiabatic logic circuits

Generator Polynomial Formulation for Parallel Counters with Applications

Parallel counters have been studied for several decades as a component in high speed multipliers and multi-operand adder circuits. Using a generator polynomial as a formalism for describing parallel counters in the general case, parallel counter properties can be derived and inferred. Furthermore, the structure and decomposition of the generator polynomial can suggest different implementation strategies. These include simple implementations of (7,3) and (15,4) parallel counters. By grouping factors, the design of a fast (7,3) parallel counter is presented. Finally, the generator polynomial is extended to permit factors of different weights. This extension provides a means for describing the design of the (5,5,4) and (4,5,5,5) multicolumn parallel counters

Uterine Contraction Modeling and Simulation

Building a training system for medical personnel to properly interpret fetal heart rate tracing requires developing accurate models that can relate various signal patterns to certain pathologies. In addition to modeling the fetal heart rate signal itself, the change of uterine pressure that bears strong relation to fetal heart rate and provides indications of maternal and fetal status should also be considered. In this work, we have developed a group of parametric models to simulate uterine contractions during labor and delivery. Through analysis of real patient records, we propose to model uterine contraction signals by three major components: regular contractions, impulsive noise caused by fetal movements, and low amplitude noise invoked by maternal breathing and measuring apparatus. The regular contractions are modeled by an asymmetric generalized Gaussian function and least squares estimation is used to compute the parameter values of the asymmetric generalized Gaussian function based on uterine contractions of real patients. Regular contractions are detected based on thresholding and derivative analysis of uterine contractions. Impulsive noise caused by fetal movements and low amplitude noise by maternal breathing and measuring apparatus are modeled by rational polynomial functions and Perlin noise, respectively. Experiment results show the synthesized uterine contractions can mimic the real uterine contractions realistically, demonstrating the effectiveness of the proposed algorithm

Categorizing Fetal Heart Rate Variability With and Without Visual Aids

Objective This study examined the ability of clinicians to correctly categorize images of fetal heart rate (FHR) variability with and without the use of exemplars. Study Design A sample of 33 labor and delivery clinicians inspected static FHR images and categorized them into one of four categories defined by the National Institute of Child Health and Human Development (NICHD) based on the amount of variability within absent, minimal, moderate, or marked ranges. Participants took part in three conditions: two in which they used exemplars representing FHR variability near the center or near the boundaries of each range, and a third control condition with no exemplars. The data gathered from clinicians were compared with those from a previous study using novices. Results Clinicians correctly categorized more images when the FHR variability fell near the center rather than the boundaries of each range, F (1,32) = 71.69, p \u3c 0.001, partial η2 = 0.69. They also correctly categorized more images when exemplars were available, F (2,64) = 5.44, p = 0.007, partial η2 = 0.15. Compared with the novices, the clinicians were more accurate and quicker in their category judgments, but this difference was limited to the condition without exemplars. Conclusion The results suggest that categorizing FHR variability is more difficult when the examples fall near the boundaries of each NICHD-defined range. Thus, clinicians could benefit from training with visual aids to improve judgments about FHR variability and potentially enhance safety in labor and delivery

The Influence of a Crosshair Visual Aid on Observer Detection of Simulated Fetal Heart Rate Signals

Objective To determine whether a visual aid overlaid on fetal heart rate (FHR) tracings increases detection of critical signals relative to images with no visual aid. Study Design In an experimental study, 21 undergraduate students viewed 240 images of simulated FHR tracings twice, once with the visual aids and once without aids. Performance was examined for images containing three different types of FHR signals (early deceleration, late deceleration, and acceleration) and four different FHR signal-to-noise ratios corresponding to FHR variability types (absent, minimal, moderate, and marked) identified by the National Institute of Child Health and Human Development (2008). Performance was analyzed using repeated-measures analyses of variance. Results The presence of the visual aid significantly improved correct detections of signals overall and decreased false alarms for the marked variability condition. Conclusion The results of the study provide evidence that the presence of a visual aid was useful in helping novices identify FHR signals in simulated maternal-fetal heart rate images. Further, the visual aid was most useful for conditions in which the signal is most difficult to detect (when FHR variability is highest)

Effective Knowledge Development in Game-Based Learning Environments

Serious games are, at their core, exploratory learning environments designed around the pedagogy and constraints associated with specific knowledge domains. This focus on instructional content is what separates games designed for entertainment from games designed to educate. As instructional designers and educators, the authors want serious game play to provide learners with a deep understanding of the domain, allowing them to use their knowledge in practice to think through multifaceted problems quickly and efficiently. Attention to the design of serious game affordances is essential to facilitating the development of domain knowledge during game play. As such, the authors contend that serious game designers should take advantage of existing prescriptions found in research on knowledge development in exploratory learning environments and tests of adaptive instructional designs in these environments. It is with this intention that the authors use evidence from research in cognitive processes and simulation design to propose design heuristics for serious game affordances to optimize knowledge development in games