Wide-band symmetrical analog multiplier IC for coherentoptical-fiber receivers operating up to 10 Gb/s

A versatile analog four-quadrant multiplier IC with large bandwidth (DC to 6 GHz and 10 Gb/s) and large dynamic range is presented. It was mainly developed for differential-phase-shift-keying (DPSK) phase demodulator and polarization diversity receivers in coherent optical-fiber transmission systems. The circuit consumes 450 mW and only needs a single power supply of -5 V. The circuit principle used allows exact symmetry with respect to both linear inputs, which reduced multiplication errors. In the intended application, especially, the time jitter and the offset voltage of the output pulse patterns are reduced to negligible values. The IC was realized in a 1.25-μm double-polysilicon bipolar technology     

Presence of pressure ulcer prevention methods used among patients considered at risk versus those considered not at risk

PURPOSE: This study examined pressure ulcer-prevention strategies available for patients considered at risk versus those considered not at risk. DESIGN: The study used a prospective, longitudinal design. SETTING AND SUBJECTS: Six hundred ninety-four patients from units of five acute care hospitals, a rehabilitation facility, and two nurses' home care caseloads participated in the investigation. INSTRUMENTS: Data-collection instruments included the Braden Scale for risk assessment, demographic information, and the Pressure Ulcer-Prevention Strategies tool, which assessed for the presence of 16 pressure ulcer-prevention strategies. METHODS: All patients admitted to a participating unit during a 2-month period were followed up until discharge. Depending on the site, patients were assessed for the presence of pressure ulcer-prevention strategies one to three times per week. RESULTS: Patients in the at-risk group versus those in the not-at-risk group were more likely (p < 0.01) to have the head of the bed in a low position, a pressure-reducing bed surface, pressure ulcer prevention charted, a positioning wedge, incontinence cleanser and ointment, heel protection, a prevention care plan, a trapeze, and a posted turning schedule. The at-risk group had significantly (p < 0.01) more prevention strategies present than did the not-at-risk group. However, the percentage of patients placed on a pressure ulcer-prevention program was low for both groups. CONCLUSIONS: Pressure ulcer prevention was evident for the at-risk group, but at a low rate. Institutions must continue to explore this critical area affecting patient outcomes.     

Semiconductor laser amplifier as optical switching gate

The properties of a semiconductor laser amplifier as optical switching gate are investigated. Particular attention is paid to gain, contrast ratio, and switching time of the device. These properties are studied experimentally and theoretically with respect to the injection current, optical input power, and cavity resonances. The experimental arrangements and the theoretical method are described. As an example of the various applications of semiconductor laser amplifier gates, packet switching experiments with self-routing, employing cascaded switching gates, are reported. In a theoretical analysis the restrictions that the properties of semiconductor laser amplifier gates impose on a larger switching system consisting of many such gates are investigated     

Hopping on Even Ground and Up Stairs with a Single Articulated Leg

This paper presents a method for generating gaits for a one-legged articulated hopping robot. A static optimization procedure produces the initial joint velocities for the flight phase, using the principle of conservation of angular momentum and assuming (nearly) passive flight. Two novel objective functions for this static optimization enable one to choose different gaits by simply changing a few parameters. A dynamic optimization procedure yields a solution for the flight trajectory that minimizes control effort. The stance phase (when the foot is touching the ground) becomes a standard two point boundary value problem, also solved with a dynamic optimization procedure. During the stance phase, the physical joint limitations, ground reaction forces, and the trajectory of the zero-moment point all constrain the solution. After these single-phase optimizations, a complete-cycle optimization procedure, incorporating both flight and stance phases, further reduces the control effort and balances the motion phases. In simulation, the leg hops on even ground and up stairs, exhibiting energy-efficient and intuitively satisfying gaits.     

Streaming-media knowledge discovery

As the amount of streaming audio and video available to World Wide Web users grows, tools for analyzing and indexing this content will become increasingly important. Frequently, knowledge management applications and information portals synthesize unstructured text information from the Web, intranets and partner sites. Given this context, we crawl a statistically significant number of Web pages, detect those that contain streaming media links, crawl the media links to extract associated meta-data, then use the crawl data to build a resource list for Web media. We have used these crawl-data findings to build a media indexing application that uses content-based indexing methods     

An evaluation of control modes in high gain manipulator systemsUne evaluation du mode de commande des systemes de manipulateurs au gain eleve

The performance of replica master and resolved motion rate control of a large manipulator is evaluated for two tasks. The first task simulates removing parts from a conveyor and stacking them on a pallet. The second task simulates stowing palletized cargo in a container.Related experiments are discussed and the results correlated to this work.Results show the bilateral master to have a distinct performance advantage over resolved motion rate control. The advantage is not as large as reported for small manipulators, however.     

Modeling of baryte batch grinding in a vibratory disc mill

A discrete population balance approach to model batch grinding is presented and used to simulate baryte grinding in a vibratory disc mill. The grinding kinetics used in the simulation are measured independently with the grinding rate depending on the particle size. A bimodal fragment size distribution of a single breakage event according to the Austin approach is used. The resulting model was solved by numerical integration and the results are discussed concerning accuracy and applicability. The experimental data are compared with the calculated results and show good agreement with the simulations. The breakage distribution is calculated for different particle sizes. This approach avoids the fitting of a large number of parameters to few experimental values, making the model more robust and allowing a wider range of applications, e.g. process optimization.     

Multi-agent programming contest 2017: lampe team description

In this paper we describe our participation in the 2017 edition of the Multi-Agent Programming Contest as team ‘lampe’. Our strategy was implemented in C++; it uses a centralised organisation of agents and evaluates different strategies based on an internal simulation of the future game state. Strategies are generated using handwritten heuristics in a randomised fashion, also relying on the internal simulation.