Agent Street: An Environment for Exploring Agent-Based Models in Second Life

Urban models can be seen on a continuum between iconic and symbolic. Generally speaking, iconic models are physical versions of the real world at some scaled down representation, while symbolic models represent the system in terms of the way they function replacing the physical or material system by some logical and/or mathematical formulae. Traditionally iconic and symbolic models were distinct classes of model but due to the rise of digital computing the distinction between the two is becoming blurred, with symbolic models being embedded into iconic models. However, such models tend to be single user. This paper demonstrates how 3D symbolic models in the form of agent-based simulations can be embedded into iconic models using the multi-user virtual world of Second Life. Furthermore, the paper demonstrates Second Life\'s potential for social science simulation. To demonstrate this, we first introduce Second Life and provide two exemplar models; Conway\'s Game of Life, and Schelling\'s Segregation Model which highlight how symbolic models can be viewed in an iconic environment. We then present a simple pedestrian evacuation model which merges the iconic and symbolic together and extends the model to directly incorporate avatars and agents in the same environment illustrating how \'real\' participants can influence simulation outcomes. Such examples demonstrate the potential for creating highly visual, immersive, interactive agent-based models for social scientists in multi-user real time virtual worlds. The paper concludes with some final comments on problems with representing models in current virtual worlds and future avenues of research.Agent-Based Modelling, Pedestrian Evacuation, Segregation, Virtual Worlds, Second Life

The Effect of Water Use and Water Availability on Net Revenues and Optimal Cropping Patterns on the Texas High Plains

Agricultural production in the High Plains region of Texas is a part of the foundation of the region’s economy. Part of the reason for this is the availability of groundwater for irrigation. Currently, the region relies on the Ogallala Aquifer for irrigation water; however, the High Plains is also home to a second aquifer, the Dockum Aquifer, which could be a viable resource for agricultural use. While the Dockum could partially replace the Ogallala, but differences in depth and pumping cost mean that it is not a perfect subsitute. The purpose of this paper is to determine how the use of water resources and crop production in the area would change if a new water resource was introduced. For each of the forty-one counties in the study area, a representative farm was established that reflects the attributes of the county including land, hydrologic, and crop specific characteristics. To estimate the optimal use of groundwater in the region and identify how the inclusion of the Dockum Aquifer affects regional production and groundwater use, a non-linear programing model was created with the objective to maximize net revenues for each county. Using the model to establish a baseline in which only Ogallala water is used, the effect of the using the Dockum Aquifer was estimated by restricting the amount of water available in the Ogallala, while making the Dockum available for use.Agricultural and Food Policy, Crop Production/Industries, Resource /Energy Economics and Policy,

An Analysis of the Feasibility of Carbon Management Policies as a Mechanism to Influence Water Conservation Using Optimization Methods

Environmental Economics and Policy,

Computational Analysis to Enhance Laminar Flow Convective Heat Transfer Rate in an Enclosure Using Aerosol Nanofluids

The current research intends to provide a starting point to effectively model aerosol heat transfer in a narrow, enclosed body. This research can lead to future modeling of nano fluids including their heat transfer characteristics and erosion effects on the walls of an enclosure. The model was developed using ICEM CFD for the mesh and FLUENT for the fluid flow modeling. Six different aspect ratio enclosures were developed to study the effects of varying aspect ratio. The natural convection of air was developed first to establish the appropriateness of the models being used. A mesh check was performed using one of the natural convection cases to ensure the mesh was appropriate. The forced convection of air was then developed. The velocity vector, isotherm, surface heat flux, and surface nusselt number were recorded for future comparison to models. The models for nanoparticle natural convection were then activated to ensure the distribution of particles was as expected. This research proved that nanoparticle tracking can be accomplished with a computer model instead of using the traditional volume ratio method. The effects of aspect ratio on the surface heat flux as well as surface nusselt number were recorded for both natural and forced convection of air. The development of the appropriate model for particle tracking is started and proven to be valid. The natural convection and forced convection of air has been solved for future comparison to natural and forced convection

Bass, Bach, and Gesualdo: Liturgical Choral Works from Three Different Periods

This paper documents the research and rehearsal process for two performances conducted by the author: Gloria by Randol Alan Bass, presented on 6 December 2016 by SIU Concert Choir, SIU Choral Union, and Southern Illinois Symphony Orchestra; and a recital program presented on 9 April 2017 by a chamber ensemble organized specially for the event, consisting of Tristis est anima mea from Responsoria Sanctae Spectantia Et Alia Ad Officium Hebdomadae by Carlo Gesualdo, O Crux Benedicta by Carlo Gesualdo, and Wer da gläubet und getauft wird by Johann Sebastian Bach (BWV 37). For each work, the following topics will be discussed: composer biography, structure and harmonic analysis, conducting considerations, and review of recordings

Mental Health Legislation and Involuntary Commitment in Nigeria: A Call for Reform

The Article focuses on the mental health issues in Nigeria which is governed by the colonial law and the Mental Health Act sponsored by the Nigerian National Assembly. It further provides an overview of the mental health legislation that is currently being followed and about the provisions of the new Act. It also focuses on the amendments to be made in the Mental Health Act based on the recommendations provided by the World Health Organization (WHO)

Evaluation of the vertical and horizontal hydraulic conductivities of household wastes

Hydraulic conductivity is a measurement of the ease of movement of a fluid through a medium and is therefore a key parameter in the design of landfill leachate management systems. Hydraulic conductivity of landfilled wastes may be affected by several factors such as overburden stress from the weight of overlying waste, water content, the type, age and pre-processing of the waste, and the presence of landfill gas. A further factor that may affect leachate movement through wastes is the predominantly horizontal orientated structure of compacted wastes. This anisotropic structure may result in hydraulic conductivity in the horizontal direction being greater than that in the vertical direction. However existing research has been effectively limited to evaluating hydraulic conductivity in a single plane and so the presence of anisotropic flow in waste remains unproven. Consequently, modelling of leachate and contaminant movement in landfills may be compromised by the use of isotropic, or assumed anisotropic, hydraulic conductivity values.The object of this research has been to assess for the first time the inherent anisotropy of two different waste samples by measuring and comparing the vertical and horizontal hydraulic conductivities over a range of stresses typical of landfill conditions. In this thesis, factors affecting the measurement of hydraulic conductivity of wastes are discussed, and details of the samples tested and test methodology are given. The results of the tests are shown and alternative test methods are discussed. The effects of gas accumulation and pore water pressure on waste hydraulic conductivity encountered during testing are also reported as further research has developed from this important finding