Assessing neural network scene classification from degraded images

Scene recognition is an essential component of both machine and biological vision. Recent advances in computer vision using deep convolutional neural networks (CNNs) have demonstrated impressive sophistication in scene recognition, through training on large datasets of labeled scene images (Zhou et al. 2018, 2014). One criticism of CNN-based approaches is that performance may not generalize well beyond the training image set (Torralba and Efros 2011), and may be hampered by minor image modifications, which in some cases are barely perceptible to the human eye (Goodfellow et al. 2015; Szegedy et al. 2013). While these “adversarial examples” may be unlikely in natural contexts, during many real-world visual tasks scene information can be degraded or limited due to defocus blur, camera motion, sensor noise, or occluding objects. Here, we quantify the impact of several image degradations (some common, and some more exotic) on indoor/outdoor scene classification using CNNs. For comparison, we use human observers as a benchmark, and also evaluate performance against classifiers using limited, manually selected descriptors. While the CNNs outperformed the other classifiers and rivaled human accuracy for intact images, our results show that their classification accuracy is more affected by image degradations than human observers. On a practical level, however, accuracy of the CNNs remained well above chance for a wide range of image manipulations that disrupted both local and global image statistics. We also examine the level of image-by-image agreement with human observers, and find that the CNNs' agreement with observers varied as a function of the nature of image manipulation. In many cases, this agreement was not substantially different from the level one would expect to observe for two independent classifiers. Together, these results suggest that CNN-based scene classification techniques are relatively robust to several image degradations. However, the pattern of classifications obtained for ambiguous images does not appear to closely reflect the strategies employed by human observers

Prediction of far-field acoustic emissions from cavitation clouds during shock wave lithotripsy for development of a clinical device

This study presents the key simulation and decision stage of a multi-disciplinary project to develop a hospital device for monitoring the effectiveness of kidney stone fragmentation by shock wave lithotripsy (SWL). The device analyses, in real time, the pressure fields detected by sensors placed on the patient's torso, fields generated by the interaction of the incident shock wave, cavitation, kidney stone and soft tissue. Earlier free-Lagrange simulations of those interactions were restricted (by limited computational resources) to computational domains within a few centimetres of the stone. Later studies estimated the far-field pressures generated when those interactions involved only single bubbles. This study extends the free-Lagrange method to quantify the bubble–bubble interaction as a function of their separation. This, in turn, allowed identification of the validity of using a model of non-interacting bubbles to obtain estimations of the far-field pressures from 1000 bubbles distributed within the focus of the SWL field. Up to this point in the multi-disciplinary project, the design of the clinical device had been led by the simulations. This study records the decision point when the project's direction had to be led by far more costly clinical trials instead of the relatively inexpensive simulations. <br/

Spontaneous ARIA (Amyloid-Related Imaging Abnormalities) and Cerebral Amyloid Angiopathy Related Inflammation in Presenilin 1-Associated Familial Alzheimer's Disease

Amyloid-related imaging abnormalities (ARIA), thought to reflect immune responses to vascular amyloid, have been detected in several amyloid-modifying therapy trials for Alzheimer's disease (AD). We report a case of ARIA developing spontaneously during the course of Presenilin 1 (PSEN1)-associated familial AD (FAD), in an APOE4 homozygous patient. Severe cerebral amyloid angiopathy with associated inflammation was subsequently found at autopsy. Recognition that ARIA may arise spontaneously during FAD and of the potential risk factors for its development are important observations given the recent launch of amyloid-modifying therapy trials for FAD

Trends in mid-latitude cyclone frequency and occurrence during fire season in the Northern Rockies: 1900-2004.

We examined changes in the timing and frequency of major midlatitude cyclones (MLCs) during August through October for eight climate stations in the Northern Rockies from 1900-2004. As MLCs can effectively diminish fire activity through both cooler temperatures and higher humidity/precipitation, we also determined if area burned by wildfires from 1940-2004 was correlated with the timing and frequency of these events. Our results indicate that: (1) significant long-term trends in MLCs exist, as the timing of the first MLC has occurred later in the year during the past century, with a marked upward shift post-mid-1980s; (2) MLC frequency has significantly declined since 1900, with a pronounced decrease also beginning in the mid-1980s; (3) the relationships between the timing of the first MLC and frequency of MLCs with forest area burned are significant; and (4) mid-tropospheric ridging upstream from the Northern Rockies that blocks MLCs has become more pronounced. Copyright 2007 by the American Geophysical Union

Reaching Millennials With Nursing History

The North Carolina Nursing History (NCNH) website, a comprehensive, award-winning, and rich educational resource, was developed by nursing and library faculty and staff at Appalachian State University and is being used by nursing faculty and students. Most of today's students prefer to learn with online tools. The advantages of using a digital nursing history website include access to an abundance and diversity of historical content in a student-friendly format

Tourism, Development, And International Relations: Discursive Productions Of Imperialism

This thesis explores how transnational tourism and “development” practices in post-colonial spaces promote and rely upon each other, creating constant tension between expectations to “develop” and tourist requirements of authenticity/exoticism. Utilizing Foucauldian, Constructivist, and Post-Colonial scholarship, I argue that cultural and ethnic tourism in “developing” or “transitioning” countries is contingent upon the commodification of local culture and environment. Content analysis and literature reviews show that the discourse around tourism and development in international relations literature has changed over time. The following chapters substantiate and provide qualitative support for four hypotheses: H1) International discourse around “development” and “tourism” is constantly changing and being produced according to interests, norms, beliefs, and resistance. H2) Patterns of discourse around “development” and “tourism” are similar and are have been produced to achieve similar goals. H3) The tourism industry offers powerful industrialized states and corporations opportunities to continue imperialist practices of political, cultural or economic advantages over previously colonized territories. H4) Cultural and ethnic tourism in Indonesia relies upon markers of perceived authenticity and exoticism that can prevent host communities from using tourism revenue to “economically develop” as policy and discourse suggests