A single photon counting X-ray imaging system, with possible applications to dual energy mammography and angiography, is presented. A silicon microstrip detector with 100 mm pitch strips is coupled to RX64 ASICs, each of them including 64 channels of preamplifier, shaper, discriminator and scaler. The system has low noise, good spatial resolution and high counting rate capability. Results on en...

The floating-gate transistor can be used to design analog circuits, such as current mirrors [1], current scaler[2] and current multiplier [3, 4] and divider [4]. The multiple input floating-gate transistor can be used to design ultra lowvoltage “pseudo differential” pairs [1], hence ULV rail-to-rail amplifiers and analog multipliers are feasible using the floating-gate technique. In this paper ...

OBJECTIVE The aim of this study was to investigate the different smear layer morphologies produced by instrumentation with a hand curette and a periodontal sonic scaler for potential removal by soft acidic solution. The effect of a new oxalate-containing phytocomplex spray in preventing tubules exposure after citric acid solution application was also evaluated. METHODS Thirty recently extract...

PURPOSE The purpose of this case-control study was to determine whether long-term ultrasonic noise exposure via the dental office environment is related to dental hygienists' hearing status. METHODS Registered dental hygienists (N = 698) who live in the Hampton Roads areas of Virginia were mailed a Dental Hygiene Work History Questionnaire to determine who would meet the inclusion criteria an...

The aim of the present study was to compare the cleansing properties of mechanical supportive care for dental implants with the use of an etching gel. Sixteen patients underwent a 5-month clinical trial with monthly recalls. These patients, wearing maxillary complete dentures and mandibular overdentures supported by a bar device on 4 implants, were treated in a split-mouth study design. Test an...

We study the design of entropy{constrained successively reenable scalar quantizers. We propose two algorithms to minimize the average distortion and design such a quantizer. We consider two sets of constraints on the entropy: (i) constraint on the average rate and (ii) constraint on aggregate rates. Both algorithms can be easily extended to design vector quantizers.

Solar Energetic Particles from the 6 November 1997 solar flare/CME(coronal mass ejection) with energies exceeding 10 GeV have been detected by Milagrito, a prototype of the Milagro Gamma Ray Observatory. While particle acceleration beyond 1 GeV at the Sun is well established, few data exist for protons or ions beyond 10 GeV. The Milagro observatory, a ground based water Cherenkov detector desig...

System design must strike a balance between energy and performance by carefully selecting the speed at which the system will run. In this work, we examine fundamental tradeoffs incurred when designing a speed scaler to minimize a weighted sum of expected response time and energy use per job. We prove that a popular dynamic speed scaling algorithm is 2-competitive for this objective and that no ...