Diagnostic tolerance for missing sensor data

For practical automated diagnostic systems to continue functioning after failure, they must not only be able to diagnose sensor failures but also be able to tolerate the absence of data from the faulty sensors. It is shown that conventional (associational) diagnostic methods will have combinatoric problems when trying to isolate faulty sensors, even if they adequately diagnose other components. Moreover, attempts to extend the operation of diagnostic capability past sensor failure will necessarily compound those difficulties. Model-based reasoning offers a structured alternative that has no special problems diagnosing faulty sensors and can operate gracefully when sensor data is missing

The effect of mutations in PRMT5 on its ability to oligomerize

Atherosclerosis is a cardiovascular disease caused by a chronic inflammatory response in the cells lining blood vessels, vascular endothelial cells. In these cells, a network of interacting proteins regulates inflammation. One of these proteins, PRMT5, regulates the inflammatory response by methylating other proteins involved in inflammation. For PRMT5 to carry out its function, it must first oligomerize with itself and various other proteins. In this study, I determined whether mutations to specific PRMT5 methylation sites affect its ability to oligomerize. By expressing PRMT5 in HEK293 cells and studying the effects of adding a chemical cross-linking agent, DMS, I was able to determine whether mutations to PRMT5 had an effect on cross-linking. My results show that post-translational modifications are required at specific sites in PRMT5 in order for successful oligomerization to occur

Model-Based Diagnosis in a Power Distribution Test-Bed

The Rodon model-based diagnosis shell was applied to a breadboard test-bed, modeling an automated power distribution system. The constraint-based modeling paradigm and diagnostic algorithm were found to adequately represent the selected set of test scenarios

LOX Expert System

The LOX Expert System is a computer program which uses artificial intelligence (AI) techniques to diagnose instrumentation problems in the shuttle liquid oxygen fueling system. The KNOBS knowledge-based system is being modified for application to this problem. System functionality and fault isolation methods are described

On the Application of a Monolithic Array for Detecting Intensity-Correlated Photons Emitted by Different Source Types

It is not widely appreciated that many subtleties are involved in the accurate measurement of intensity-correlated photons; even for the original experiments of Hanbury Brown and Twiss (HBT). Using a monolithic 4x4 array of single-photon avalanche diodes (SPADs), together with an off-chip algorithm for processing streaming data, we investigate the difficulties of measuring second-order photon correlations g2 in a wide variety of light fields that exhibit dramatically different correlation statistics: a multimode He-Ne laser, an incoherent intensity-modulated lamp-light source and a thermal light source. Our off-chip algorithm treats multiple photon-arrivals at pixel-array pairs, in any observation interval, with photon fluxes limited by detector saturation, in such a way that a correctly normalized g2 function is guaranteed. The impact of detector background correlations between SPAD pixels and afterpulsing effects on second-order coherence measurements is discussed. These results demonstrate that our monolithic SPAD array enables access to effects that are otherwise impossible to measure with stand-alone detectors.Comment: 17 pages, 6 figure

Atypical birdsong and artificial languages provide insights into how communication systems are shaped by learning, use and transmission

In this article, I argue that a comparative approach focusing on the cognitive capacities and behavioral mechanisms that underlie vocal learning in songbirds and humans can provide valuable insights into the evolutionary origins of language. The experimental approaches I discuss use abnormal song and atypical linguistic input to study the processes of individual learning, social interaction, and cultural transmission. Atypical input places increased learning and communicative pressure on learners, so exploring how they respond to this type of input provides a particularly clear picture of the biases and constraints at work during learning and use. Furthermore, simulating the cultural transmission of these unnatural communication systems in the laboratory informs us about how learning and social biases influence the structure of communication systems in the long run. Findings based on these methods suggest fundamental similarities in the basic social–cognitive mechanisms underlying vocal learning in birds and humans, and continuing research promises insights into the uniquely human mechanisms and into how human cognition and social behavior interact, and ultimately impact on the evolution of language

Eye contact perception at distances up to six meters

Common experience suggests that most people can tell whether they are being looked at by another person who is about 8 m away. However, the results of past experiments, which used distances of no more than about 3 m, have implied that this cannot be done if the person looked at (Receiver) judges only by the iris-sclera configuration of the person looking (Sender). This is true even if eye contact is defined simply as identifying on-face gazes (FGs). It has been suggested that in everyday experience eye contact is accompanied by cues other than iris position, and that these non-iris-position (NIP) cues to Receiver account for recognition at longer distances. The hypotheses of the present experiment are that FGs can be identified at considerably more than 3 m, without NIP cues: and that this happens because as features of Sender\u27s lower face fall within Receiver\u27s central vision at longer distances, Receiver is able to use them for triangulating the position of Sender\u27s irises

Sex Differences And Vocal Flexibility In Wild Parrot Communication

Parrots are renowned in captivity for their vocal flexibility, and although studies of avian vocal learning focus largely on songbirds, there is some evidence that the majority of parrots may be more vocally flexible than many members of the songbird order. In addition, unlike the majority of most temperate songbirds, both male and female parrots produced learned vocalizations and often share a repertoire of calls, although anecdotal evidence from pet owners suggests that males may be the more vocally flexible sex. However, most of what we know about parrot vocal flexibility and sex differences in parrot communication comes from anecdotal evidence and very limited lab studies that have difficulty mimicking natural parrot social conditions. Thus, the purpose of this work was to investigate how wild parrots are using vocal flexibility during interactions with conspecifics, and how sex differences in communication are expressed in vocal interactions in general and vocal flexibility in particular. I studied two geographically and phylogenetically distant parrot species, the Australian galah (Eolophus roseicapillus) and the neotropical orange-fronted conure (Aratinga canicularis) to address these issues. I conducted four playback experiments either to wild, free-ranging individuals or to wild-caught captives held temporarily in aviaries. Two of these experiments address how parrots are using and interpreting rapid, short-term vocal flexibility during their interactions and how this differs by sex. The other two experiments address more broadly how male and female parrots respond to male and female affiliative and aggressive calls. This thesis demonstrates that in at least two species of parrots, males and females differ in how they rapidly modify their vocalizations during interactions with conspecifics. Despite sharing a repertoire of calls, both galahs and orange-fronted conures distinguish the sex of a caller based solely on acoustic cues, and males and females interact differently with conspecific callers, suggesting that the sex of interactants is a highly relevant factor even during interactions that do not seem to be primarily for the purpose of mate attraction. These experiments begin to shed light on the incredible intricacies of flexible parrot vocal communication