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The Influence of Disease Mapping Methods on Spatial Patterns and Neighborhood Characteristics for Health Risk

Description: This thesis addresses three interrelated challenges of disease mapping and contributes a new approach for improving visualization of disease burdens to enhance disease surveillance systems. First, it determines an appropriate threshold choice (smoothing parameter) for the adaptive kernel density estimation (KDE) in disease mapping. The results show that the appropriate threshold value depends on the characteristics of data, and bandwidth selector algorithms can be used to guide such decisions about mapping parameters. Similar approaches are recommended for map-makers who are faced with decisions about choosing threshold values for their own data. This can facilitate threshold selection. Second, the study evaluates the relative performance of the adaptive KDE and spatial empirical Bayes for disease mapping. The results reveal that while the estimated rates at the state level computed from both methods are identical, those at the zip code level are slightly different. These findings indicate that using either the adaptive KDE or spatial empirical Bayes method to map disease in urban areas may provide identical rate estimates, but caution is necessary when mapping diseases in non-urban (sparsely populated) areas. This study contributes insights on the relative performance in terms of accuracy of visual representation and associated limitations. Lastly, the study contributes a new approach for delimiting spatial units of disease risk using straightforward statistical and spatial methods and social determinants of health. The results show that the neighborhood risk map not only helps in geographically targeting where but also in tailoring interventions in those areas to those high risk populations. Moreover, when health data is limited, the neighborhood risk map alone is adequate for identifying where and which populations are at risk. These findings will benefit public health tasks of planning and targeting appropriate intervention even in areas with limited and poor-quality health data. This study not only fills the identified ...
Date: December 2017
Creator: Ruckthongsook, Warangkana
Partner: UNT Libraries

Reverberation Mapping of High-Luminosity Quasars

Description: This article presents the CIV BLR size and luminosity relation over eight orders of magnitude in luminosity, pushing the luminosity limit to its highest point so far.
Date: August 31, 2017
Creator: Kaspi, Shai; Brandt, William Nielsen; Maoz, Dan; Netzer, Hagai; Schneider, Donald P. & Shemmer, Ohad
Partner: UNT College of Arts and Sciences

Case Studies to Learn Human Mapping Strategies in a Variety of Coarse-Grained Reconfigurable Architectures

Description: Computer hardware and algorithm design have seen significant progress over the years. It is also seen that there are several domains in which humans are more efficient than computers. For example in image recognition, image tagging, natural language understanding and processing, humans often find complicated algorithms quite easy to grasp. This thesis presents the different case studies to learn human mapping strategy to solve the mapping problem in the area of coarse-grained reconfigurable architectures (CGRAs). To achieve optimum level performance and consume less energy in CGRAs, place and route problem has always been a major concern. Making use of human characteristics can be helpful in problems as such, through pattern recognition and experience. Therefore to conduct the case studies a computer mapping game called UNTANGLED was analyzed as a medium to convey insights of human mapping strategies in a variety of architectures. The purpose of this research was to learn from humans so that we can come up with better algorithms to outperform the existing algorithms. We observed how human strategies vary as we present them with different architectures, different architectures with constraints, different visualization as well as how the quality of solution changes with experience. In this work all the case studies obtained from exploiting human strategies provide useful feedback that can improve upon existing algorithms. These insights can be adapted to find the best architectural solution for a particular domain and for future research directions for mapping onto mesh-and- stripe based CGRAs.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: May 2017
Creator: Malla, Tika Kumari
Partner: UNT Libraries

Improving the Gameplay Experience and Guiding Bottom Players in an Interactive Mapping Game

Description: In game based learning, motivating the players to learn by providing them a desirable gameplay experience is extremely important. However, it's not an easy task considering the quality of today's commercial non-educational games. Throughout the gameplay, the player should neither get overwhelmed nor under-challenged. The best way to do so is to monitor the player's actions in the game because these actions can tell the reason behind the player's performance. They can also tell about the player's lacking competencies or knowledge. Based on this information, in-game educational interventions in the form of hints can be provided to the player. The success of such games depends on their interactivity, motivational outlook and thus player retention. UNTANGLED is an online mapping game based on crowd-sourcing, developed by Reconfigurable Computing Lab, UNT for the mapping problem of CGRAs. It is also an educational game for teaching the concepts of reconfigurable computing. This thesis performs qualitative comparative analysis on gameplays of low performing players of UNTANGLED. And the implications of this analysis are used to provide recommendations for improving the gameplay experience for these players by guiding them. The recommendations include strategies to reach a high score and a compact solution, hints in the form of preset patterns and a clustering based approach.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: May 2017
Creator: Ambekar, Kiran
Partner: UNT Libraries

An Investigation of Preservice Teachers' Understanding of Buoyancy

Description: The purpose of this study was to examine the conceptual understandings of 55 elementary preservice teachers for the concept of buoyancy. This study used Ausubel’s Assimilation Theory (Ausubel, 1963) as a framework for a 15-week intervention that used pre/post concept maps (Cmaps), pre/post face-to-face semi-structured interviews, and drawings as evidences for change of formation of cognitive structures. Using a convergent parallel design and mixed methods approach, preservice teachers’ conceptions were analyzed using these evidences. Results of the study show that preservice teachers held both scientific conceptions and misconceptions about buoyancy as a force before and after an instructional intervention. Of importance were the existence of robust misconceptions about buoyancy that included inaccurate scientific knowledge about the foundational concepts of gravity, weight, mass, and density. The largest gains in scientific knowledge included the concepts of gravity, surface area, opposing forces, and the buoyant force. These concepts were consistently supported with evidence from post-concept maps, post, semi-structured interviews, and drawings. However, high frequencies of misconceptions were associated with these same aforementioned concepts as well as additional misconceptions about buoyancy-related concepts (i.e., weight, density, displacement, and sinking/floating). A paired t test showed a statistically significant difference (t = -3.504, p = .001) in the total number of scientifically correct concepts for the pre-concept maps (M = 0.51, SD = .879) and post-concept maps (M = 1.25, SD = 1.542). The Cohen’s d effect size was small, .47. Even through gains for the pre/post concept maps were noted, a qualitative analysis of the results indicated that not only were there serious gaps in the participant’s scientific understanding of buoyancy, after the instructional intervention an increased number of misconceptions were presented alongside the newly learned concepts. A paired t test examining misconceptions showed that there was a statistically significant difference (t = -3.160, p = ...
Date: May 2016
Creator: Kirby, Benjamin
Partner: UNT Libraries

Influence of the Choice of Disease Mapping Method on Population Characteristics in Areas of High Disease Burdens

Description: Disease maps are powerful tools for depicting spatial variations in disease risk and its underlying drivers. However, producing effective disease maps requires careful consideration of the statistical and spatial properties of the disease data. In fact, the choice of mapping method influences the resulting spatial pattern of the disease, as well as the understanding of its underlying population characteristics. New developments in mapping methods and software in addition to continuing improvements in data quality and quantity are requiring map-makers to make a multitude of decisions before a map of disease burdens can be created. The impact of such decisions on a map, including the choice of appropriate mapping method, not been addressed adequately in the literature. This research demonstrates how choice of mapping method and associated parameters influence the spatial pattern of disease. We use four different disease-mapping methods – unsmoothed choropleth maps, smoothed choropleth maps produced using the headbanging method, smoothed kernel density maps, and smoothed choropleth maps produced using spatial empirical Bayes methods and 5-years of zip code level HIV incidence (2007- 2011) data from Dallas and Tarrant Counties, Texas. For each map, the leading population characteristics and their relative importance with regards to HIV incidence is identified using a regression analysis of a CDC recommended list of socioeconomic determinants of HIV. Our results show that the choice of mapping method leads to different conclusions regarding the associations between HIV disease burden and the underlying demographic and socioeconomic characteristics. Thus, the choice of mapping method influences the patterns of disease we see or fail to see. Accurate depiction of areas of high disease burden is important for developing and targeting appropriate public health interventions.
Date: December 2015
Creator: Desai, Khyati Sanket
Partner: UNT Libraries

Spatially Explicit Modeling of West Nile Virus Risk Using Environmental Data

Description: West Nile virus (WNV) is an emerging infectious disease that has widespread implications for public health practitioners across the world. Within a few years of its arrival in the United States the virus had spread across the North American continent. This research focuses on the development of a spatially explicit GIS-based predictive epidemiological model based on suitable environmental factors. We examined eleven commonly mapped environmental factors using both ordinary least squares regression (OLS) and geographically weighted regression (GWR). The GWR model was utilized to ascertain the impact of environmental factors on WNV risk patterns without the confounding effects of spatial non-stationarity that exist between place and health. It identifies the important underlying environmental factors related to suitable mosquito habitat conditions to make meaningful and spatially explicit predictions. Our model represents a multi-criteria decision analysis approach to create disease risk maps under data sparse situations. The best fitting model with an adjusted R2 of 0.71 revealed a strong association between WNV infection risk and a subset of environmental risk factors including road density, stream density, and land surface temperature. This research also postulates that understanding the underlying place characteristics and population composition for the occurrence of WNV infection is important for mitigating future outbreaks. While many spatial and aspatial models have attempted to predict the risk of WNV transmission, efforts to link these factors within a GIS framework are limited. One of the major challenges for such integration is the high dimensionality and large volumes typically associated with such models and data. This research uses a spatially explicit, multivariate geovisualization framework to integrate an environmental model of mosquito habitat with human risk factors derived from socio-economic and demographic variables. Our results show that such an integrated approach facilitates the exploratory analysis of complex data and supports reasoning about the underlying spatial ...
Date: December 2015
Creator: Kala, Abhishek K.
Partner: UNT Libraries

Multiplying by Division: Mapping the Collection at University of North Texas Libraries

Description: Presentation given at the Charleston Conference on November 7, 2015 This presentation focuses on the University of North Texas Libraries' Collection Map, a collection assessment tool used to provide additional data and increased flexibility. The presentation centers on "an assessment-based future" for UNT Libraries and details an improved system in which collections are proactively assessed.
Date: August 7, 2015
Creator: Harker, Karen; Klein, Janette & Crawford, Laurel
Partner: UNT Libraries

UNT Collection Map: A Data-Organization Tool for Subject-Based Collections

Description: Poster was shown at the Cross Timbers Library Collaborative (CTLC) Conference on August 7, 2015. It coincided with a presentation on the University of North Texas Libraries' Collection Map, a collection assessment tool used to provide additional data and increased flexibility. The poster gives the objectives, as well as the methods, results, improvements, and future applications associated with the system.
Date: August 7, 2015
Creator: Harker, Karen & Klein, Janette
Partner: UNT Libraries

Effects of Non-homogeneous Population Distribution on Smoothed Maps Produced Using Kernel Density Estimation Methods

Description: Understanding spatial perspectives on the spread and incidence of a disease is invaluable for public health planning and intervention. Choropleth maps are commonly used to provide an abstraction of disease risk across geographic space. These maps are derived from aggregated population counts that are known to be affected by the small numbers problem. Kernel density estimation methods account for this problem by producing risk estimates that are based on aggregations of approximately equal population sizes. However, the process of aggregation often combines data from areas with non-uniform spatial and population characteristics. This thesis presents a new method to aggregate space in ways that are sensitive to their underlying risk factors. Such maps will enable better public health practice and intervention by enhancing our ability to understand the spatial processes that result in disparate health outcomes.
Date: December 2014
Creator: Jones, Jesse Jack
Partner: UNT Libraries

Preservation Health Check: Monitoring Threats to Digital Repository Content

Description: The Open Planets Foundation (OPF) has suggested the need for digital preservation repositories to perform periodic “health checks” as a routine part of their preservation activities. In the same way that doctors monitor basic health properties of their patients to spot indications of infirmity, repositories should monitor a set of properties associated with “preservation health” to provide an early warning of potential threats to the ongoing security of the archived digital objects in their care. The Preservation Health Check (PHC) project, undertaken as a joint effort by OPF and OCLC Research, aims to evaluate the usefulness of the preservation metadata created and maintained by operational repositories for assessing basic preservation properties. The PHC project seeks to develop an implementable logic to support preservation health checks of this kind, and to test this logic against the store of preservation metadata maintained by an operational preservation repository. The Bibliothèque Nationale de France has agreed to share their preservation metadata in support of this project. The authors aim is to advance the use of preservation metadata as an evidence base for conducting preservation health checks according to a standardized, widely-applicable protocol. Doing so opens up possibilities for internal or third-party threat assessment services that can be used for internal repository planning and auditing/certification. Accordingly, this paper provides background on the problem addressed by the PHC project, the authors' approach for operationalizing the concept of a preservation health check, some preliminary findings, and next steps. The report is important for anyone involved with defining, implementing and promoting the use of preservation metadata and for those trying to get a handle on how preservation metadata works with threat models.
Date: April 2014
Creator: Kool, Wouter; Werf, Titia van der & Lavoie, Brian
Partner: UNT Libraries


Description: GrayQb{trademark} is a novel technology that has the potential to characterize radioactively contaminated areas such as hot cells, gloveboxes, small and large rooms, hallways, and waste tanks. The goal of GrayQb{trademark} is to speed the process of decontaminating these areas, which reduces worker exposures and promotes ALARA considerations. The device employs Phosphorous Storage Plate (PSP) technology as its primary detector material. PSPs, commonly used for medical applications and non-destructive testing, can be read using a commercially available scanner. The goal of GrayQb{trademark} technology is to locate, quantify, and identify the sources of contamination. The purpose of the work documented in this report was to better characterize the performance of GrayQb{trademark} in its ability to present overlay images of the PSP image and the associated visual image of the location being surveyed. The results presented in this report are overlay images identifying the location of hot spots in both controlled and field environments. The GrayQb{trademark} technology has been mainly tested in a controlled environment with known distances and source characteristics such as specific known radionuclides, dose rates, and strength. The original concept for the GrayQb{trademark} device involved utilizing the six faces of a cube configuration and was designed to be positioned in the center of a contaminated area for 3D mapping. A smaller single-faced GrayQb{trademark}, dubbed GrayQb SF, was designed for the purpose of conducting the characterization testing documented in this report. This lighter 2D version is ideal for applications where entry ports are too small for a deployment of the original GrayQb™ version or where only a single surface is of interest. The shape, size, and weight of these two designs have been carefully modeled to account for most limitations encountered in hot cells, gloveboxes, and contaminated areas. GrayQb{trademark} and GrayQb{trademark} SF share the same fundamental detection system design (e.g., ...
Date: December 12, 2013
Creator: Mayer, J.; Farfan, E.; Immel, D.; Phillips, M.; Bobbitt, J. & Plummer, J.
Partner: UNT Libraries Government Documents Department

National-Scale Wind Resource Assessment for Power Generation (Presentation)

Description: This presentation describes the current standards for conducting a national-scale wind resource assessment for power generation, along with the risk/benefit considerations to be considered when beginning a wind resource assessment. The presentation describes changes in turbine technology and viable wind deployment due to more modern turbine technology and taller towers and shows how the Philippines national wind resource assessment evolved over time to reflect changes that arise from updated technologies and taller towers.
Date: August 1, 2013
Creator: Baring-Gould, E. I.
Partner: UNT Libraries Government Documents Department

Energy DataBus (Fact Sheet)

Description: NREL has developed the Energy DataBus, an open-sourced software that collects massive amounts of energy-related data at second-to-second intervals; stores it in a massive, scalable database; and turns it into useful information.
Date: July 1, 2013
Partner: UNT Libraries Government Documents Department

Mapping the Southwest Project: Putting the Region's Maps Online

Description: This poster discusses the Mapping the Southwest Project, involving putting our region's maps online. The poster includes background information on the project, the project plan, workflow and equipment, and the impacts and lessons learned.
Date: May 7, 2013
Creator: Alemneh, Daniel Gelaw; Jones, Jerrell; Hartman, Cathy Nelson; Phillips, Mark Edward; Hodges, Ann & Kadri, Carolyn
Partner: UNT Libraries

DOE Robotic and Remote Systems Assistance to the Government of Japan

Description: At the request of the Government of Japan, DOE did a complex wide survey of available remotely operated and robotic systems to assist in the initial assessment of the damage to the Fukushima Daiichi reactors following an earthquake and subsequent tsunami. As a result several radiation hardened cameras and a Talon robot were identified as systems that could immediately assist in the effort and were subsequently sent to Japan. These systems were transferred to the Government of Japan and used to map radiation levels surrounding the damaged facilities. This report describes the equipment, its use, data collected, and lessons learned from the experience.
Date: February 1, 2013
Creator: Wadsworth, Derek & Walker, Victor
Partner: UNT Libraries Government Documents Department

Modelling spatial concordance between Rocky Mountain spotted fever disease incidence and habitat probability of its vector Dermacentor variabilis (American dog tick)

Description: This article reports on the development and comparison of two maps of Texas related to Rocky Mountain spotted fever.
Date: November 1, 2012
Creator: Atkinson, Samuel F.; Sarkar, Sahotra; Avina, Aldo; Schuermann, Jim A. & Williamson, Phillip C.
Partner: UNT College of Arts and Sciences


Description: The high-field performance of SRF cavities will eventually be limited by the realization of fundamental material limits, whether it is Hc1 or Hsh, or some derivative thereof, at which the superconductivity is lost. Before reaching this fundamental field limit at the macro level, it must be encountered at localized, perhaps microscopic, sites of field enhancement due to local topography. If such sites are small enough, they may produce thermally stabilized normal-conducting regions which contribute non-linear losses when viewed from the macro resonant field perspective, and thus produce degradation in Q0. We have undertaken a calculation of local surface magnetic field enhancement from specific fine topographic structure by conformal mapping method and numerically. A solution of the resulting normal conducting volume has been derived and the corresponding RF Ohmic loss simulated.
Date: July 1, 2012
Creator: Chen Xu,Charles Reece,Michael Kelley
Partner: UNT Libraries Government Documents Department

Haven't a Cue? Mapping the CUE Space as an Aid to HRA Modeling

Description: Advances in automation present a new modeling environment for the human reliability analysis (HRA) practitioner. Many, if not most, current day HRA methods have their origin in characterizing and quantifying human performance in analog environments where mode awareness and system status indications are potentially less comprehensive, but simpler to comprehend at a glance when compared to advanced presentation systems. The introduction of highly complex automation has the potential to lead to: decreased levels of situation awareness caused by the need for increased monitoring; confusion regarding the often non-obvious causes of automation failures, and emergent system dependencies that formerly may have been uncharacterized. Understanding the relation of incoming cues available to operators during plant upset conditions, in conjunction with operating procedures, yields insight into understanding the nature of the expected operator response in this control room environment. Static systems methods such as fault trees do not contain the appropriate temporal information or necessarily specify the relationship among cues leading to operator response. In this paper, we do not attempt to replace standard performance shaping factors commonly used in HRA nor offer a new HRA method, existing methods may suffice. In this paper we strive to enhance current understanding of the basis for operator response through a technique that can be used during the qualitative portion of the HRA analysis process. The CUE map is a means to visualize the relationship among salient cues in the control room that help influence operator response, show how the cognitive map of the operator changes as information is gained or lost, and is applicable to existing as well as advanced hybrid plants and small modular reactor designs. A brief application involving loss of condensate is presented and advantages and limitations of the modeling approach and use of the CUE map are discussed.
Date: June 1, 2012
Creator: Gertman, David I; Boring, Ronald L; Hugo, Jacques & Phoenix, William
Partner: UNT Libraries Government Documents Department