Analyzing Interaction Patterns to Verify a Simulation/Game Model

Thesis (Ph.D.) - Indiana University, School of Education, 2012In order for simulations and games to be effective for learning, instructional designers must verify that the underlying computational models being used have an appropriate degree of fidelity to the conceptual models of their real-world counterparts. A simulation/game that provides incorrect feedback is likely to promote misunderstanding and adversely affect learning and transfer. Numerous methods for verifying the accuracy of a computational model exist, but it is generally accepted that no single method is adequate and that multiple methods should be used. The purpose of this study was to propose and test a new method for collecting and analyzing users' interaction data (e.g., choices made, actions taken, results and feedback obtained) to provide quantified evidence that the underlying computational model of a simulation/game represents the conceptual model with sufficient accuracy. In this study, analysis of patterns in time (APT) was used to compare gameplay results from the Diffusion Simulation Game (DSG) with predictions based on diffusion of innovations theory (DOI). A program was written to automatically play the DSG by analyzing the game state during each turn, seeking patterns of game component attributes that matched optimal strategies based on DOI theory. When the use of optimal strategies did not result in the desired number of successful games, here defined as the threshold of confidence for model verification, further investigation revealed flaws in the computational model. These flaws were incrementally corrected and subsequent gameplay results were analyzed until the threshold of confidence was achieved. In addition to analysis of patterns in time for model verification (APTMV), other verification methods used included code walkthrough, execution tracing, desk checking, syntax checking, and statistical analysis. The APTMV method was found to be complementary to these other methods, providing quantified evidence of the computational model's degree of accuracy and pinpointing flaws that could be corrected to improve fidelity. The APTMV approach to verification and improvement of computational models is described and compared with other methods, and improvements to the process are proposed

On the Time Dependence of Holographic Complexity

We evaluate the full time dependence of holographic complexity in various eternal black hole backgrounds using both the complexity=action (CA) and the complexity=volume (CV) conjectures. We conclude using the CV conjecture that the rate of change of complexity is a monotonically increasing function of time, which saturates from below to a positive constant in the late time limit. Using the CA conjecture for uncharged black holes, the holographic complexity remains constant for an initial period, then briefly decreases but quickly begins to increase. As observed previously, at late times, the rate of growth of the complexity approaches a constant, which may be associated with Lloyd's bound on the rate of computation. However, we find that this late time limit is approached from above, thus violating the bound. Adding a charge to the eternal black holes washes out the early time behaviour, i.e., complexity immediately begins increasing with sufficient charge, but the late time behaviour is essentially the same as in the neutral case. We also evaluate the complexity of formation for charged black holes and find that it is divergent for extremal black holes, implying that the states at finite chemical potential and zero temperature are infinitely more complex than their finite temperature counterparts.Comment: 52+31 pages, 30 figure

On the Time Dependence of Holographic Complexity

We evaluate the full time dependence of holographic complexity in various eternal black hole backgrounds using both the complexity=action (CA) and the complexity=volume (CV) conjectures. We conclude using the CV conjecture that the rate of change of complexity is a monotonically increasing function of time, which saturates from below to a positive constant in the late time limit. Using the CA conjecture for uncharged black holes, the holographic complexity remains constant for an initial period, then briefly decreases but quickly begins to increase. As observed previously, at late times, the rate of growth of the complexity approaches a constant, which may be associated with Lloyd's bound on the rate of computation. However, we find that this late time limit is approached from above, thus violating the bound. Adding a charge to the eternal black holes washes out the early time behaviour, i.e., complexity immediately begins increasing with sufficient charge, but the late time behaviour is essentially the same as in the neutral case. We also evaluate the complexity of formation for charged black holes and find that it is divergent for extremal black holes, implying that the states at finite chemical potential and zero temperature are infinitely more complex than their finite temperature counterparts.Comment: 52+31 pages, 30 figure

Assured crew return capability Crew Emergency Return Vehicle (CERV) avionics

The Crew Emergency Return Vehicle (CERV) is being defined to provide Assured Crew Return Capability (ACRC) for Space Station Freedom. The CERV, in providing the standby lifeboat capability, would remain in a dormat mode over long periods of time as would a lifeboat on a ship at sea. The vehicle must be simple, reliable, and constantly available to assure the crew's safety. The CERV must also provide this capability in a cost effective and affordable manner. The CERV Project philosophy of a simple vehicle is to maximize its useability by a physically deconditioned crew. The vehicle reliability goes unquestioned since, when needed, it is the vehicle of last resort. Therefore, its systems and subsystems must be simple, proven, state-of-the-art technology with sufficient redundancy to make it available for use as required for the life of the program. The CERV Project Phase 1'/2 Request for Proposal (RFP) is currently scheduled for release on October 2, 1989. The Phase 1'/2 effort will affirm the existing project requirements or amend and modify them based on a thorough evaluation of the contractor(s) recommendations. The system definition phase, Phase 2, will serve to define CERV systems and subsystems. The current CERV Project schedule has Phase 2 scheduled to begin October 1990. Since a firm CERV avionics design is not in place at this time, the treatment of the CERV avionics complement for the reference configuration is not intended to express a preference with regard to a system or subsystem

Adrenocortical and Adipose Responses to High-Altitude-Induced, Long-Term Hypoxia in the Ovine Fetus

By late gestation, the maturing hypothalamo-pituitary-adrenal (HPA) axis aids the fetus in responding to stress. Hypoxia represents a significant threat to the fetus accompanying situations such as preeclampsia, smoking, high altitude, and preterm labor. We developed a model of high-altitude (3,820 m), long-term hypoxia (LTH) in pregnant sheep. We describe the impact of LTH on the fetal HPA axis at the level of the hypothalamic paraventricular nucleus (PVN), anterior pituitary corticotrope, and adrenal cortex. At the PVN and anterior pituitary, the responses to LTH are consistent with hypoxia being a potent activator of the HPA axis and potentially maladaptive, while the adrenocortical response to LTH appears to be primarily adaptive. We discuss mechanisms involved in the delicate balance between these seemingly opposing responses that preserve the normal ontogenic rise in fetal plasma cortisol essential for organ maturation and in this species, birth. Further, we examine the response to, and ramifications of, an acute secondary stressor in the LTH fetus. We provide an integrative model on the potential role of adipose in modulating these responses to LTH. Integration of these adaptive responses to LTH plays a key role in promoting normal fetal growth and development under conditions of a chronic stress

MARBLE: A system for executing expert systems in parallel

This paper details the MARBLE 2.0 system which provides a parallel environment for cooperating expert systems. The work has been done in conjunction with the development of an intelligent computer-aided design system, ICADS, by the CAD Research Unit of the Design Institute at California Polytechnic State University. MARBLE (Multiple Accessed Rete Blackboard Linked Experts) is a system of C Language Production Systems (CLIPS) expert system tool. A copied blackboard is used for communication between the shells to establish an architecture which supports cooperating expert systems that execute in parallel. The design of MARBLE is simple, but it provides support for a rich variety of configurations, while making it relatively easy to demonstrate the correctness of its parallel execution features. In its most elementary configuration, individual CLIPS expert systems execute on their own processors and communicate with each other through a modified blackboard. Control of the system as a whole, and specifically of writing to the blackboard is provided by one of the CLIPS expert systems, an expert control system

Trophic polymorphism in a terrestrial salamander

Question: Does habitat heterogeneity promote trophic polymorphism in a terrestrial salamander? Hypothesis: Eastern red-backed salamanders (Plethodon cinereus) in upland and lowland habitats differ morphologically because their prey’s size differs between those habitats. Field site: Five mature hardwood forests in central New York and northern Pennsylvania, USA, with known differences in diet between upland and lowland habitats. Methods: We collected animals and examined their stomach contents and their cranial morphology, the latter with digital stereomicroscope images and morphometric methods. Results: We found morphological differences between upland and lowland salamanders, although there was a considerable phenotypic range for both habitats. Lowland salamanders generally had relatively shorter heads and a lower jaw/head ratio, and upland salamanders generally had the converse. Within and among habitats, cranial morphology was associated with diet, where salamanders with lowland-like morphology consumed more large prey and fewer small prey, and salamanders with upland-like morphology consumed the converse. Conclusions: The observed trophic polymorphism and association with food use within populations suggests that this variation may accentuate variation at larger scales, and may play an important role in diversification within the genus

The Ursinus Weekly, April 5, 1907

The German-American patriot • Baseball outlook • Pictures for history room • Athletic Association • Musical clubs • Here and there • Intercollegiate • Alumni notes • Reserves\u27 baseball schedule • Literary Supplement: The college bell; Menominee; Rudyard Kipling; The passing of the American home; The methods of Thomas Morrishttps://digitalcommons.ursinus.edu/weekly/2939/thumbnail.jp