Hewlett-Packard

About: Hewlett-Packard is a company organization based out in Palo Alto, California, United States. It is known for research contribution in the topics: Signal & Layer (electronics). The organization has 34663 authors who have published 59808 publications receiving 1467218 citations. The organization is also known as: Hewlett Packard & Hewlett-Packard Company.

Maximal entanglement versus entropy for mixed quantum states

Abstract: Maximally entangled mixed states are those states that, for a given mixedness, achieve the greatest possible entanglement. For two-qubit systems and for various combinations of entanglement and mixedness measures, the form of the corresponding maximally entangled mixed states is determined primarily analytically. As measures of entanglement, we consider entanglement of formation, relative entropy of entanglement, and negativity; as measures of mixedness, we consider linear and von Neumann entropies. We show that the forms of the maximally entangled mixed states can vary with the combination of (entanglement and mixedness) measures chosen. Moreover, for certain combinations, the forms of the maximally entangled mixed states can change discontinuously at a specific value of the entropy. Along the way, we determine the states that, for a given value of entropy, achieve maximal violation of Bell's inequality.

Accurate 3D pose estimation from a single depth image

Abstract: This paper presents a novel system to estimate body pose configuration from a single depth map. It combines both pose detection and pose refinement. The input depth map is matched with a set of pre-captured motion exemplars to generate a body configuration estimation, as well as semantic labeling of the input point cloud. The initial estimation is then refined by directly fitting the body configuration with the observation (e.g., the input depth). In addition to the new system architecture, our other contributions include modifying a point cloud smoothing technique to deal with very noisy input depth maps, a point cloud alignment and pose search algorithm that is view-independent and efficient. Experiments on a public dataset show that our approach achieves significantly higher accuracy than previous state-of-art methods.

Crowdsourcing, Attention and Productivity

Abstract: The tragedy of the digital commons does not prevent the copious voluntary production of content that one witnesses in the web. We show through an analysis of a massive data set from YouTube that the productivity exhibited in crowdsourcing exhibits a strong positive dependence on attention, measured by the number of downloads. Conversely, a lack of attention leads to a decrease in the number of videos uploaded and the consequent drop in productivity, which in many cases asymptotes to no uploads whatsoever. Moreover, uploaders compare themselves to others when having low productivity and to themselves when exceeding a threshold.

Sensor, apparatus and method for non-invasive measurement of oxygen saturation

Abstract: A sensor for non-invasive measurement of oxygen saturation using the reflection method comprises a red transmitter (55), an infrared transmitter (58) and a receiver (57). The distances between the transmitters and the receiver are selected such that the length of the light path (60, 61) between the red transmitter (55) and the receiver (57) is substantially equal to the length of the light path (62, 63) between the infrared transmitter (58) and the receiver (57). The sensor comprises a further red transmitter (56) which is used for another application at the human body or another tissue characteristics where the depth of penetration at the various wavelengths is different from the shown example. Together with an appropriate oximeter, manual or automatic adaptation is possible. Further signal improvement may be obtained by autocorrelating the received signal, detecting its frequency and cross-correlating it with a pattern function of the same frequency.

System for analyzing and debugging embedded software through dynamic and interactive use of code markers

Abstract: A system (Figure 10) for inserting code markers for observing indications (external to the microprocessor upon which the software operates) of the occurrence of an event in the execution of the software. Additional instructions or markers are added to the software to be debugged to produce simple, encoded, memory references to otherwise unused memory or I/O locations that will always be visible to a logic analyzer as bus cycles. Although the code markers cause a minimal intrusion in the underlying software, they make tracing events by a conventional logic analyzer much simpler and allow for performance evaluations in manners not heretofore possible. In particular, the inserted code markers provide a method of dynamically extracting information from a running host or real-time "black box" embedded system (902) under test using simple low intrusion print statements, encoded I/O writes on procedure entries and exits, and/or an interface to service calls and the like which writes out the passed parameters. Generally, the code markers are inserted at compile time or interactively during the debug session to make visible critical points in the code execution, such as function calls, task creation, semaphore operations and other resource usage so as to speed isolation of problems at test points during debugging. Performance analysis and event analysis use the code markers of the invention to cut through the ambiguities of microprocessor prefetch and cache operations. Because of these features, the invention is particularly advantageous for use by software design teams developing complex embedded host or real-time operating systems using multi-task operating systems and/or object oriented systems.