User-centered visual analysis using a hybrid reasoning architecture for intensive care units

One problem pertaining to Intensive Care Unit information systems is that, in some cases, a very dense display of data can result. To ensure the overview and readability of the increasing volumes of data, some special features are required (e.g., data prioritization, clustering, and selection mechanisms) with the application of analytical methods (e.g., temporal data abstraction, principal component analysis, and detection of events). This paper addresses the problem of improving the integration of the visual and analytical methods applied to medical monitoring systems. We present a knowledge- and machine learning-based approach to support the knowledge discovery process with appropriate analytical and visual methods. Its potential benefit to the development of user interfaces for intelligent monitors that can assist with the detection and explanation of new, potentially threatening medical events. The proposed hybrid reasoning architecture provides an interactive graphical user interface to adjust the parameters of the analytical methods based on the users' task at hand. The action sequences performed on the graphical user interface by the user are consolidated in a dynamic knowledge base with specific hybrid reasoning that integrates symbolic and connectionist approaches. These sequences of expert knowledge acquisition can be very efficient for making easier knowledge emergence during a similar experience and positively impact the monitoring of critical situations. The provided graphical user interface incorporating a user-centered visual analysis is exploited to facilitate the natural and effective representation of clinical information for patient care

Hubble Space Telescope Imaging of the Ultra-Compact High Velocity Cloud AGC 226067: A stripped remnant in the Virgo Cluster

We analyze the optical counterpart to the ultra-compact high velocity cloud AGC 226067, utilizing imaging taken with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The color magnitude diagram of the main body of AGC 226067 reveals an exclusively young stellar population, with an age of $\sim$7--50 Myr, and is consistent with a metallicity of [Fe/H]$\sim$$-$0.3 as previous work has measured via HII region spectroscopy. Additionally, the color magnitude diagram is consistent with a distance of $D$$\approx$17 Mpc, suggesting an association with the Virgo cluster. A secondary stellar system located $\sim$1.6' ($\sim$8 kpc) away in projection has a similar stellar population. The lack of an old red giant branch ($\gtrsim$5 Gyr) is contrasted with a serendipitously discovered Virgo dwarf in the ACS field of view (Dw J122147+132853), and the total diffuse light from AGC~226067 is consistent with the luminosity function of the resolved $\sim$7--50 Myr stellar population. The main body of AGC~226067 has a $M_{V}$=$-$11.3$\pm$0.3, or $M_{stars}$=5.4$\pm$1.3$\times$10$^4$ $M_{\odot}$ given the stellar population. We searched 20 deg$^2$ of imaging data adjacent to AGC~226067 in the Virgo Cluster, and found two similar stellar systems dominated by a blue stellar population, far from any massive galaxy counterpart -- if this population has similar star formation properties as AGC~226067, it implies $\sim$0.1 $M_{\odot}$ yr$^{-1}$ in Virgo intracluster star formation. Given its unusual stellar population, AGC~226067 is likely a stripped remnant and is plausibly the result of compressed gas from the ram pressure stripped M86 subgroup ($\sim$350 kpc away in projection) as it falls into the Virgo Cluster.Comment: 9 pages, 4 figures, 1 table. Accepted by the Astrophysical Journa

Inertia and Change in the Early Years: Employment Relations in Young, High Technology Firms

[Excerpt] This paper considers processes of organizational imprinting in a sample of 100 young, high technology companies. It examines the effects of a pair of initial conditions: the founders\u27 models of the employment relation and their business strategies. Our analyses indicate that these two features were well aligned when the firms were founded. However, the alignment has deteriorated over time, due to changes in the distribution of employment models. In particular, the \u27star\u27 model and \u27commitment\u27 model are less stable than the \u27engineering\u27 model and the \u27factory\u27 model. Despite their instability, these two blueprints for the employment relation have strong effects in shaping the early evolution of these firms. In particular, firms that embark with these models have significantly higher rates of replacing the founder chief executive with a non-founder as well as higher rates of completing an initial public stock offering. Some implications of these findings for future studies of imprinting and inertia in organizations are discussed

Site response analysis and microzonation of Anchorage, Alaska, USA, using strong-motion data from recent earthquakes

This thesis was previously held under moratorium from 5/11/21 to 5/05/22Anchorage, Alaska, is located in one of the most active tectonic settings in the world. The city and region were significantly impacted by the MW9.2 Great Alaska Earthquake in 1964, and they were recently shaken by a MW7.1 event in 2018. The city was developed in an area underlain by complex soil deposits of varied geological origins and stiffnesses, with the deposits’ thicknesses increasing east to west. Situated at the edge of the North American Plate, with the actively subducting Pacific Plate below, Anchorage is susceptible to both intraslab and interface earthquakes, along with crustal earthquakes. Strong-motion stations were installed across the city in an attempt to capture the variability in site response. Strong-motion recordings from 35 stations over the years of 2004 to 2019 were collected, processed, and prepared for analysis of that variability. The Generalized Inversion Technique (GIT) was used to calculate the Fourier spectral amplification at each strong-motion station and the variability of amplification at 1 Hz and 5 Hz were mapped for Anchorage. The 2018 MW7.1 strong-motion recordings were compared to the lower-magnitude events in the database to evaluate the differences at strong-motion stations related to linear and nonlinear site response. The horizontal to vertical spectral ratio (HVSR) was calculated for each strong-motion station and regional relationships between fpeak and the time-averaged shear wave velocity in the upper 30m (VS30) were developed. A contour map estimating seismic site class across Anchorage was developed using 70 VS30 estimates and measurements at other locations. A methodology is also developed using Fourier spectral amplification and Random Vibration Theory (RVT) to estimate engineering site response spectra at strong-motion stations. An approach to address nonlinear site response is applied to the methodology because the database is predominantly composed of linear site response recordings.Anchorage, Alaska, is located in one of the most active tectonic settings in the world. The city and region were significantly impacted by the MW9.2 Great Alaska Earthquake in 1964, and they were recently shaken by a MW7.1 event in 2018. The city was developed in an area underlain by complex soil deposits of varied geological origins and stiffnesses, with the deposits’ thicknesses increasing east to west. Situated at the edge of the North American Plate, with the actively subducting Pacific Plate below, Anchorage is susceptible to both intraslab and interface earthquakes, along with crustal earthquakes. Strong-motion stations were installed across the city in an attempt to capture the variability in site response. Strong-motion recordings from 35 stations over the years of 2004 to 2019 were collected, processed, and prepared for analysis of that variability. The Generalized Inversion Technique (GIT) was used to calculate the Fourier spectral amplification at each strong-motion station and the variability of amplification at 1 Hz and 5 Hz were mapped for Anchorage. The 2018 MW7.1 strong-motion recordings were compared to the lower-magnitude events in the database to evaluate the differences at strong-motion stations related to linear and nonlinear site response. The horizontal to vertical spectral ratio (HVSR) was calculated for each strong-motion station and regional relationships between fpeak and the time-averaged shear wave velocity in the upper 30m (VS30) were developed. A contour map estimating seismic site class across Anchorage was developed using 70 VS30 estimates and measurements at other locations. A methodology is also developed using Fourier spectral amplification and Random Vibration Theory (RVT) to estimate engineering site response spectra at strong-motion stations. An approach to address nonlinear site response is applied to the methodology because the database is predominantly composed of linear site response recordings

No Fault Found events in maintenance engineering Part 2: Root causes, technical developments and future research

This is the second half of a two paper series covering aspects of the no fault found (NFF) phenomenon, which is highly challenging and is becoming even more important due to increasing complexity and criticality of technical systems. Part 1 introduced the fundamental concept of unknown failures from an organizational, behavioral and cultural stand point. It also reported an industrial outlook to the problem, recent procedural standards, whilst discussing the financial implications and safety concerns. In this issue, the authors examine the technical aspects, reviewing the common causes of NFF failures in electronic, software and mechanical systems. This is followed by a survey on technological techniques actively being used to reduce the consequence of such instances. After discussing improvements in testability, the article identifies gaps in literature and points out the core areas that should be focused in the future. Special attention is paid to the recent trends on knowledge sharing and troubleshooting tools; with potential research on technical diagnosis being enumerated

Abstracts: HASTAC 2017: The Possible Worlds of Digital Humanities

The document contains abstracts for HASTAC 2017

Master of Science

thesisDiscrimination of delayed emissions from photonuclear fission events provides the necessary information for the detection of nuclear materials. The time and energy characteristics of signature signals provide unique fingerprints which can be used for the identification and quantification of fissionable isotopes using γ-ray spectroscopy. This investigation explores measurement results of β-delayed γ-rays from photofission events. During the experiment, spectroscopy measurements were taken using two high-purity germanium detectors while three separate signal processing units were used for data acquisition. Interrogation of 238U, 239Pu, and 232Th was performed using a 22 MeV pulsed bremsstrahlung photon beam. Fission fragments with energies above 3 MeV were identified as delayed-fission γ-rays unique to the fissionable materials. A numerical model of the experimental setup is also proposed as part of this research. This model is based on the Monte Carlo radiation transport code MCNPX. The data from the experiment were used to validate the numerical models. Additionally, photonuclear data libraries were tested in the numerical model for consistency and accuracy. The numerical results showed a good agreement with the experimental data, specifically the comparison of 238U. Discrepancies between the numerical results and experimental data of 232Th were observed. A new photonuclear data library from TENDL/ACE was then implemented for 232Th and the numerical results were improved. One of the main contributions of this work is the development of a reliable computational model that gives almost the same results that could be performed on a physical experimentation as a less expensive option to examine the factors that could fall behind the spectroscopy measurements

Analysis of Background Check Policy in Higher Education

In the higher education environment today, lack of agreement about background checks between campus community members, fueled by unresolved tensions between security and privacy, has led many universities to adopt a patchwork of fragmented background check policies. Many of these policies have been created and accepted without careful consideration of the wide array of risks and complexities involved with background checks. This policy analysis examined the experiences and history behind Georgia Institute of Technology’s adoption of background check policy. This was achieved through interviewing relevant constituents and analyzing of all available/related official policy documents associated with Georgia Tech’s Pre-employment Background Check Policy and Program. This dissertation presents a chronological account of the events and influences associated with Georgia Tech’s adoption and revision of background check policy. Results of this study offer valuable insights and recommendations for further study in order to assist higher education policy makers and HR professionals at other universities in making more informed decisions regarding the challenges involved with background check, and similar, policy. Some of these insights include an awareness of societal tensions that exist between privacy and security policy; the importance of understanding how national, local, and organizational level triggering events have shaped and contributed to higher education background check policy that is based on a general concern for security; and my recommendation for further study into background check policy as it will relate to the higher matriculation process