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Population dynamics of minimally cognitive individuals. Part I: Introducing knowledge into the dynamics

Description: The author presents a new approach for modeling the dynamics of collections of objects with internal structure. Based on the fact that the behavior of an individual in a population is modified by its knowledge of other individuals, a procedure for accounting for knowledge in a population of interacting objects is presented. It is assumed that each object has partial (or complete) knowledge of some (or all) other objects in the population. The dynamical equations for the objects are then modified to include the effects of this pairwise knowledge. This procedure has the effect of projecting out what the population will do from the much larger space of what it could do, i.e., filtering or smoothing the dynamics by replacing the complex detailed physical model with an effective model that produces the behavior of interest. The procedure therefore provides a minimalist approach for obtaining emergent collective behavior. The use of knowledge as a dynamical quantity, and its relationship to statistical mechanics, thermodynamics, information theory, and cognition microstructure are discussed.
Date: July 1, 1995
Creator: Schmieder, R.W.
Partner: UNT Libraries Government Documents Department

Energy consumption and expenditure projections by population group on the basis on the annual energy outlook 2000 forecast.

Description: The changes in the patterns of energy use and expenditures by population group are analyzed by using the 1993 and 1997 Residential Energy Consumption Surveys. Historically, these patterns have differed among non-Hispanic White households, non-Hispanic Black households, and Hispanic households. Patterns of energy use and expenditures are influenced by geographic and metropolitan location, the composition of housing stock, economic and demographic status, and the composition of energy use by end-use category. As a consequence, as energy-related factors change across groups, patterns of energy use and expenditures also change. Over time, with changes in the composition of these factors by population group and their variable influences on energy use, the impact on energy use and expenditures has varied across these population groups.
Date: May 31, 2001
Creator: Poyer, D. A. & Sciences, Decision and Information
Partner: UNT Libraries Government Documents Department


Description: This taxonomic key was devised to support development of a Rapid Bioassessment Protocol using ants at the Savannah River Site. The emphasis is on 'rapid' and, because the available keys contained a very large number of genera not known to occur at the Savannah River Site, we found that the available keys were unwieldy. Because these keys contained many more genera than we would ever encounter and because this larger number of genera required more couplets in the key and often required examination of characters that are difficult to assess without higher magnifications (60X or higher), more time was required to process samples. In developing this set of keys I emphasized character states that are easier for nonspecialists to recognize. I recognize that the character sets used may lead to some errors but I believe that the error rate will be small and, for the purpose of rapid bioassessment, this error rate will be acceptable provided that overall sample sizes are adequate. Oliver and Beattie (1996a, 1996b) found that for rapid assessment of biodiversity the same results were found when identifications were done to morphospecies by people with minimal expertise as when the same data sets were identified by subject matter experts. Basset et al. (2004) concluded that it was not as important to correctly identify all species as it was to be sure that the study included as many functional groups as possible. If your study requires high levels of accuracy, it is highly recommended that, when you key out a specimen and have any doubts concerning the identification, you should refer to keys in Bolton (1994) or to the other keys used to develop this area specific taxonomic key.
Date: September 4, 2007
Creator: Martin, D
Partner: UNT Libraries Government Documents Department


Description: Wild pig (Sus scrofa) collisions with vehicles are known to occur in the United States, but only minimal information describing these accidents has been reported. In an effort to better characterize these accidents, data were collected from 179 wild pig-vehicle collisions from a location in west central South Carolina. Data included accident parameters pertaining to the animals involved, time, location, and human impacts. The age structure of the animals involved was significantly older than that found in the population. Most collisions involved single animals; however, up to seven animals were involved in individual accidents. As the number of animals per collision increased, the age and body mass of the individuals involved decreased. The percentage of males was significantly higher in the single-animal accidents. Annual attrition due to vehicle collisions averaged 0.8 percent of the population. Wild pig-vehicle collisions occurred year-round and throughout the 24-hour daily time period. Most accidents were at night. The presence of lateral barriers was significantly more frequent at the collision locations. Human injuries were infrequent but potentially serious. The mean vehicle damage estimate was $1,173.
Date: May 23, 2007
Creator: Mayer, J & Paul E. Johns, P
Partner: UNT Libraries Government Documents Department

Explorations in combining cognitive models of individuals and system dynamics models of groups.

Description: This report documents a demonstration model of interacting insurgent leadership, military leadership, government leadership, and societal dynamics under a variety of interventions. The primary focus of the work is the portrayal of a token societal model that responds to leadership activities. The model also includes a linkage between leadership and society that implicitly represents the leadership subordinates as they directly interact with the population. The societal model is meant to demonstrate the efficacy and viability of using System Dynamics (SD) methods to simulate populations and that these can then connect to cognitive models depicting individuals. SD models typically focus on average behavior and thus have limited applicability to describe small groups or individuals. On the other hand, cognitive models readily describe individual behavior but can become cumbersome when used to describe populations. Realistic security situations are invariably a mix of individual and population dynamics. Therefore, the ability to tie SD models to cognitive models provides a critical capability that would be otherwise be unavailable.
Date: July 1, 2008
Creator: Backus, George A.
Partner: UNT Libraries Government Documents Department

Innovative MIOR Process Utilizing Indigenous Reservoir Constituents

Description: This research program is directed at improving the knowledge of reservoir ecology and developing practical microbial solutions for improving oil production. The goal is to identify indigenous microbial populations which can produce beneficial metabolic products and develop a methodology to stimulate those select microbes with nutrient amendments to increase oil recovery. This microbial technology has the capability of producing multiple oil-releasing agents. Experimental laboratory work is underway. Microbial cultures have been isolated from produced water samples. Comparative laboratory studies demonstrating in situ production of microbial products as oil recovery agents were conducted in sand packs with natural field waters with cultures and conditions representative of oil reservoirs. Field pilot studies are underway.
Date: March 31, 2003
Creator: Hitzman, D. O.; Stepp, A. K.; Dennis, D. M. & Graumann, L. R.
Partner: UNT Libraries Government Documents Department

Evaluate Habitat Use and Population Dynamics of Lampreys in Cedar Creek, Annual Report 2002.

Description: Pacific lamprey (Lampetra tridentata) in the Columbia River basin have declined to a remnant of their pre-1940s populations and the status of the western brook lamprey (L. richardsoni) and river lamprey (L. ayresi) is unknown. Identifying the biological and ecological factors limiting lamprey populations is critical to their recovery, but little research has been conducted on these species within the Columbia River basin. This ongoing, multi-year study examines lamprey populations in Cedar Creek, Washington, a third-order tributary to the Lewis River. This annual report describes the activities and results of the third year of this project. Adult (n = 62), metamorphosed (n = 76), transforming (n = 4), and ammocoete (n = 315) stages of Pacific and western brook lamprey were examined in 2002. Lampreys were captured using adult fish ladders, lamprey pots, rotary screw traps, and lamprey electrofishers. In addition, fifty-four spawning ground surveys were conducted during which 124 Pacific lamprey and 13 western brook lamprey nests were identified. Stream gradient of spawning grounds were surveyed to better understand spawning habitat requirements.
Date: March 1, 2003
Creator: Pirtle, Jodi; Stone, Jennifer & Barndt, Scott
Partner: UNT Libraries Government Documents Department

Dynamic light-matter coupling across multiple spatial dimensions in a quantum dots-in-a-well heterostructure

Description: Semiconductor heterostructures incorporating multiple degrees of spatial confinement have recently attracted substantial interest for photonic applications. One example is the quantum dots-in-a-well (DWELL) heterostructure, consisting of zero-dimensional quantum dots embedded in a two-dimensional quantum well and surrounded by three-dimensional bulk material. This structure offers several advantages over conventional photonic devices while providing a model system for the study of light-matter interactions across multiple spatial dimensions. Here, we use ultrafast differential transmission spectroscopy2 to temporally and spectrally resolve density-dependent carrier dynamics in a DWELL heterostructure. We observe excitation-dependent shifts of the quantum dot energy levels at low densities, while at high densities we observe an anomalous induced absorption at the quantum dot excited state that is correlated to quantum well population dynamics. These studies of density-dependent light-matter interactions across multiple coupled spatial dimensions provide clues to the underlying physics governing quantum dot properties, with important implications for DWELL-based photonic devices.
Date: January 1, 2009
Creator: Prasankumar, Rohit P; Taylor, Antoinette J; Chow, W W; Attaluri, R S & Shenoi, R
Partner: UNT Libraries Government Documents Department

Proc. Agent 2004 Conf. on Social Dynamics : Interaction, Reflexivity and Emergence

Description: I'd like to welcome you to the Agent 2004 conference. As most of you are aware, this conference is the fifth in a series of meetings that began in 1999. A conference followed the next year in 2000. The 2001 conference was skipped because of some conflicts with other conferences, and the conferences have proceeded annually since then. We have the proceedings of the previous conferences available here on CDs. One CD has the proceedings from 1999, 2000, and 2002; the other contains last year's proceedings. The purpose of these conferences is to advance the state of the computational social sciences and to integrate the social sciences with the decision sciences and something that is traditionally known as the management sciences. Those of you in the operations/research area are familiar with the traditional school of modeling simulation that emerged from that scientific area. This conference will bring together a different group of people to talk about the topic of agent-based theories and simulations. This fifth agent conference is one of a group of conferences held annually around the country. Most of you are probably aware of the CASOS Conference held at Carnegie Mellon University, usually in July. UCLA holds the Arrowhead Conference, generally around May. The University of Michigan is now holding a conference as well. Of course everyone is aware of SwarmFest, which has been held annually for about a decade. The Swarm seems to 'swarm' in different locations each year. As you're well aware, this conference is organized into a three-day program. This is the first time we've used three days for the full conference setting. Last year, we held simultaneous sessions, and that didn't work well for most of those who attended. We had complaints from people who missed sessions and papers because of scheduling, so we ...
Date: January 1, 2004
Creator: C. M. Macal, D. Sallach, M. J. North, eds.
Partner: UNT Libraries Government Documents Department

Agent 2003 Conference on Challenges in Social Simulation

Description: Welcome to the Proceedings of the fourth in a series of agent simulation conferences cosponsored by Argonne National Laboratory and The University of Chicago. Agent 2003 is the second conference in which three Special Interest Groups from the North American Association for Computational Social and Organizational Science (NAACSOS) have been involved in planning the program--Computational Social Theory; Simulation Applications; and Methods, Toolkits and Techniques. The theme of Agent 2003, Challenges in Social Simulation, is especially relevant, as there seems to be no shortage of such challenges. Agent simulation has been applied with increasing frequency to social domains for several decades, and its promise is clear and increasingly visible. Like any nascent scientific methodology, however, it faces a number of problems or issues that must be addressed in order to progress. These challenges include: (1) Validating models relative to the social settings they are designed to represent; (2) Developing agents and interactions simple enough to understand but sufficiently complex to do justice to the social processes of interest; (3) Bridging the gap between empirically spare artificial societies and naturally occurring social phenomena; (4) Building multi-level models that span processes across domains; (5) Promoting a dialog among theoretical, qualitative, and empirical social scientists and area experts, on the one hand, and mathematical and computational modelers and engineers, on the other; (6) Using that dialog to facilitate substantive progress in the social sciences; and (7) Fulfilling the aspirations of users in business, government, and other application areas, while recognizing and addressing the preceding challenges. Although this list hardly exhausts the challenges the field faces, it does identify topics addressed throughout the presentations of Agent 2003. Agent 2003 is part of a much larger process in which new methods and techniques are applied to difficult social issues. Among the resources that give us the ...
Date: January 1, 2003
Creator: Clemmons, Margaret
Partner: UNT Libraries Government Documents Department

Studying the incommensurability that unites us: persuasion across discourse communities, persuasion via boundary objects

Description: In the science studies literature the theoretical construct of boundary objects has been developed to explain how diverse communities clustered around a scientific subject area cooperate to advance that area. Boundary objects are 'scientific objects that inhabit several intersecting social worlds . . . and satisfy the informational requirements of each of them' (Star and Griesemer 393). Star and Griesemer's foundational article showed that these objects can be shared by communities ranging from academic researchers to amateur enthiasts, adminsitrators, philanthropists, and technicians. While each community understands the object differently, there is enough commonality in the understanding of the object to unite these distinct social worlds and facilitate cooperation among them.
Date: January 1, 2003
Creator: Wilson, G. D. (Gregory D.)
Partner: UNT Libraries Government Documents Department