Abstract: Disclosed is an apparatus and method for a compact, rugged, and inexpensive spectrometer that will make possible a range of new applications for optical spectroscopy including point-of-care medical devices, personal monitors, and ubiquitous environmental sensing. Embodiments of the disclosure include silicon photodetectors where incident light passes through a layer of an inexpensive, absorbing thin film. In one embodiment, one or more photodetectors may be used where a series of absorbing thin film layers are passed over the photodetectors. In another embodiment, an absorbing thin film layer is placed over one or more photodetectors where the absorptivity of the thin film layer is different for each photodetector.

Abstract: Disclosed is an apparatus and method for a compact, rugged, and inexpensive spectrometer that will make possible a range of new applications for optical spectroscopy including point-of-care medical devices, personal monitors, and ubiquitous environmental sensing. Embodiments of the disclosure include silicon photodetectors where incident light passes through a layer of an inexpensive, absorbing thin film. In one embodiment, one or more photodetectors may be used where a series of absorbing thin film layers are passed over the photodetectors. In another embodiment, an absorbing thin film layer is placed over one or more photodetectors where the absorptivity of the thin film layer is different for each photodetector.

Abstract: The present invention generally relates to polymers with lasing characteristics that allow the polymers to be useful in detecting analytes. In one aspect, the polymer, upon an interaction with an analyte, may exhibit a change in a lasing characteristic that can be determined in some fashion. For example, interaction of an analyte with the polymer may affect the ability of the polymer to reach an excited state that allows stimulated emission of photons to occur, which may be determined, thereby determining the analyte. In another aspect, the polymer, upon interaction with an analyte, may exhibit a change in stimulated emission that is at least 10 times greater with respect to a change in the spontaneous emission of the polymer upon interaction with the analyte. The polymer may be a conjugated polymer in some cases. In one set of embodiments, the polymer includes one or more hydrocarbon side chains, which may be parallel to the polymer backbone in some instances.

Abstract: Disclosed is a complete SAT solver, Chaff, which is one to two orders of magnitude faster than existing SAT solvers. Using the Davis-Putnam (DP) backtrack search strategy, Chaff employs efficient Boolean Constraint Propagation (BCP), termed two literal watching, and a low overhead decision making strategy, termed Variable State Independent Decaying Sum (VSIDS). During BCP, Chaff watches two literals not assigned to zero. The literals can be specifically ordered or randomly selected. VSIDS ranks variables, the highest-ranking literal having the highest counter value, where counter value is incremented by one for each occurrence of a literal in a clause. Periodically, the counters are divided by a constant to favor literals included in recently created conflict clauses. VSIDS can also be used to select watched literals, the literal least likely to be set (i.e., lowest VSIDS rank, or lowest VSIDS rank combined with last decision level) being selected to watch.