A new design for estimating the distribution of time to pregnancy is proposed and investigated. The design is based on recording current durations in a cross-sectional sample of women, leading to statistical problems similar to estimating renewal time distributions from backward recurrence times. Non-parametric estimation is studied in some detail and a parametric approach is indicated. The res...

The topic of “how many users” is of great interest to usability specialists who need to balance project concerns over ROI and timelines with their own concerns about designing usable interfaces. The panel will review the current controversies over usability test sample size, test validity, and reliability. Introduction Virzi (1992), Nielsen and Landauer (1993), and Lewis (1994) published influe...

| A new current-mode, low-power, lowvoltage and high-speed CMOS sample-and-hold circuit has been designed and fabricated. A new currentmode di erential switching scheme has been adopted to eliminate errors caused by feedthrough injection from the sample switches. The experimental result yields 9-bit resolution in 9mW power dissipation, in a 20MHz clock frequency from a 3V power supply.

New CMOS current samplehold (CSH) circuits capable of overcoming the accuracy limitations in conventional circuits without significantly reducing operating speed are proposed and analyzed. A novel differential clock feedthrough attenuation (DCFA) technique is developed to attenuate the signal-dependent clock feedthrough errors. Unlike conventional techniques, the DCFA circuit allows the use of ...

We present electrical measurements of high-frequency magnetic dynamics excited by spin-polarized currents in Co/Cu/Ni(80)Fe20 nanopillar devices, with a magnetic field applied perpendicular to the sample layers. As a function of current and magnetic field, the dynamical phase diagram contains several distinguishable precessional modes and also static magnetic states. Using detailed comparisons ...

The potential and current distributions are calculated across the width of a quantum Hall effect sample for applied currents between 0 μA and 225 μA. For the first time, both a confining potential and a current-induced charge-redistribution potential are used. The confining potential has a parabolic shape, and the charge-redistribution potential is logarithmic. The solution for the sum of the t...

Nowadays, there is a growing need for applications in food and environmental areas able to cope with the analysis of a large number of analytes in very complex matrices [1]. The new analytical procedures demand sensitivity, robustness, effectiveness and high resolution with reduced analysis time. Many of these requirements may be met to a certain extent by the total or partial automation of the...

Formulae to estimate premorbid memory functioning in a sample of cognitively intact older adults have been developed. These formulae were validated in a small sample of patients with amnestic Mild Cognitive Impairment. However, further validation is clearly needed. The current study applied these formulae to a sample of 1,059 patients referred to a dementia clinic and compared the premorbid est...

High-throughput microbial electrolysis cells (MECs) were used to perform treatability studies on many different refinery wastewater samples all having appreciably different characteristics, which resulted in large differences in current generation. A de-oiled refinery wastewater sample from one site (DOW1) produced the best results, with 2.1±0.2 A/m(2) (maximum current density), 79% chemical ox...