357 research outputs found
Computerized Evaluation of Individual State Modules
A report on the May 22, 1969 meeting of Appalachian Adult Basic Education Demonstration Center held in Lexington, Kentucky compiled by Jude T. Cotter
Fault detection monitor circuit provides ''self-heal capability'' in electronic modules - A concept
Self-checking technique detects defective solid state modules used in electronic test and checkout instrumentation. A ten bit register provides failure monitor and indication for 1023 comparator circuits, and the automatic fault-isolation capability permits the electronic subsystems to be repaired by replacing the defective module
Multimode ergometer system
System overcomes previous ergometer design and calibration problems including inaccurate measurements, large weight, size, and input power requirements, poor heat dissipation, high flammability, and inaccurate calibration. Device consists of lightweight, accurately controlled ergometer, restraint system, and calibration system
Dialogue State Induction Using Neural Latent Variable Models
Dialogue state modules are a useful component in a task-oriented dialogue
system. Traditional methods find dialogue states by manually labeling training
corpora, upon which neural models are trained. However, the labeling process
can be costly, slow, error-prone, and more importantly, cannot cover the vast
range of domains in real-world dialogues for customer service. We propose the
task of dialogue state induction, building two neural latent variable models
that mine dialogue states automatically from unlabeled customer service
dialogue records. Results show that the models can effectively find meaningful
slots. In addition, equipped with induced dialogue states, a state-of-the-art
dialogue system gives better performance compared with not using a dialogue
state module.Comment: IJCAI 202
Ultrasensitivity and Fluctuations in the Barkai-Leibler Model of Chemotaxis Receptors in {\it Escherichia coli}
A stochastic version of the Barkai-Leibler model of chemotaxis receptors in
{\it E. coli} is studied here to elucidate the effects of intrinsic network
noise in their conformational dynamics. It was originally proposed to explain
the robust and near-perfect adaptation of {\it E. coli} observed across a wide
range of spatially uniform attractant/repellent (ligand) concentrations. A
receptor is either active or inactive and can stochastically switch between the
two states. Enzyme CheR methylates inactive receptors while CheB demethylates
active ones and the probability for it to be active depends on its level of
methylation and ligandation. A simple version of the model with two methylation
sites per receptor (M=2) shows zero-order ultrasensitivity (ZOU) akin to the
classical 2-state model of covalent modification studied by Goldbeter and
Koshland (GK). For extremely small and large ligand concentrations, the system
reduces to two 2-state GK modules. A quantitative measure of the spontaneous
fluctuations in activity (variance) estimated mathematically under linear noise
approximation (LNA) is found to peak near the ZOU transition. The variance is a
weak, non-monotonic and decreasing functions of ligand and receptor
concentrations. Gillespie simulations for M=2 show excellent agreement with
analytical results obtained under LNA. Numerical results for M=2, 3 and 4 show
ZOU in mean activity; the variance is found to be smaller for larger M. The
magnitude of receptor noise deduced from available experimental data is
consistent with our predictions. A simple analysis of the downstream signaling
pathway shows that this noise is large enough to have a beneficial effect on
the motility of the organism. The response of mean receptor activity to small
time-dependent changes in the external ligand concentration, computed within
linear response theory, is found to have a bilobe form.Comment: Accepted in PLoS On
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