Assessing user interfaces for diverse user groups: evaluation strategies and defining characteristics

User interface designers are challenged to design for diverse users, including those of different genders, cultures and abilities; however, little research has been directed at this problem. One factor which may inhibit such research is its cost. This paper presents an approach which offers a way to seek out important characteristics of designs in a cost-effective way and reports on the results. In a study reported here, subjects from different nationalities and of both genders evaluated three dialog boxes specifically designed for 'white American women'. 'European adult male intellectuals', and 'English-speaking-internationals'. The dialog boxes were evaluated with conjoint techniques of preference rankings, and factor-analysed adjective ratings. These results showed that female subjects had stronger and more consistent patterns of preferences than the male subjects. All subjects preferred interfaces rated high on an accessibility factor and disliked complex layouts; this effect was even stronger for women. Nationality did not effect ratings. Gender had a stronger effect on the outcome than nationality.     

PET: a proton/electron telescope for studies of magnetospheric,solar, and galactic particles

The proton/electron telescope (PET) on SAMPEX (Solar, Anomalous, and Magnetospheric Particle Explorer) is designed to provide measurements of energetic electrons and light nuclei from solar, Galactic, and magnetospheric sources. PET is an all solid-state system that will measure the differential energy spectra of electrons from ~1 to ~30 MeV and H and He nuclei from ~20 to ~300 MeV/nucleon, with isotope resolution of H and He extending from ~20 to ~80 MeV/nucleon. As SAMPEX scans all local times and geomagnetic cutoffs over the course of its near-polar orbit, PET will characterize precipitating relativistic electron events during periods of declining solar activity, and it will examine whether the production rate of odd nitrogen and hydrogen molecules in the middle atmosphere by precipitating electrons is sufficient to affect O₃ depletion. In addition, PET will complement studies of the elemental and isotopic composition of energetic heavy (Z>2) nuclei on SAMPEX by providing measurements of H, He, and electrons. Finally, PET has limited capability to identify energetic positrons from potential natural and man-made sources     

Paper and electronic diaries: Too early for conclusions on compliance rates and their effects--Comment on Green, Rafaeli, Bolger, Shrout, and Reis (2006).

This commentary discusses 4 issues relevant to interpretation of A. S. Green, E. Rafaeli, N. Bolger, P. E. Shrout, and H. T. Reis's (2006) article (see record 2006-03820-006): (a) Self-reported compliance in medical settings has generally been substantially higher than verified compliance, suggesting that this is not a rare phenomenon; (b) none of the studies reported in Green et al. explicitly verified paper diary compliance; (c) the impact of participant motivation on diary compliance is unknown, and it may be difficult for researchers to accurately assess it in their own studies; and (d) without objective verification of diary compliance, analysis of the effects of noncompliance on data quality is difficult to interpret. The authors conclude that compliance in paper diaries and the effects of noncompliance on data quality are still unsettled issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A new sensor for detecting partial discharges in operating turbinegenerators

A partial discharge (PD) sensor has been developed which is able to unequivocally differentiate between PD in the winding and all types of electrical interference. Thus, the sensor will permit an online test for turbine generators, similar to the test now used for hyrogenerators. The sensor requires no high-voltage connection to the winding, and is easily installed in the stator slot, underneath the wedges. Noise is differentiated from PD by the shapes of the electrical pulses from the sensor. The sensor, called the Stator Slot Coupler (SSC), is essentially a directional electromagnetic coupler. Calculations as well as laboratory tests indicate that the couplers can easily survive the electrical, thermal, magnetic, and mechanical stresses in the generator     

Air-Bubble Method of Locking Central-Vein Catheters for Prevention of Hub Colonization: A Pilot Study

Background: The major source of catheter‐associated bacteremia is contamination of the catheter hub during connection–disconnection procedures. A new method of catheter locking has been developed wherein anticoagulant is injected first, followed by a 0.1‐mL air bubble and 0.9 mL of bactericidal solution. The anticoagulant is then located at the catheter tip and the bactericidal solution is located at the catheter hub. The air bubble prevents mixing of the two solutions. The bactericidal solution was acidified concentrated saline (ACS). The 27% saline solution has a pH of 2.0. ACS was chosen because it is theoretically harmless if injected in the amount used to lock the catheter lumens. The goals of this pilot study were to determine whether the new method of catheter locking is easy to perform with available syringes and whether eventual injection of the experimental solution is well tolerated. Methods: Ten patients were randomly assigned, either to heparin lock (5 patients, 62 treatments) or air‐bubble method (5 patients, 56 treatments). In the control group, the catheters were locked with heparin, 5000 U/mL. In the experimental group, the catheters were locked with heparin, air bubble, and ACS. Altogether, the lumens were overfilled by 0.2 mL. Results: Compared to the routine method, the experimental method required a 1‐ to 2‐min‐longer procedure time. There were no errors in proper sequence of injections into the lumina. There were no episodes of bacteremia related to hub contamination in either group. In the air‐bubble group, there was one case of bacteremia associated with purulent drainage from the exit and the same organism in both cultures. In three instances in each group, the locking solution could not be aspirated and was injected without any subjective symptoms or objective signs. Conclusion: We conclude that the air‐bubble method of locking central‐vein catheters is easy to perform. In three instances of air‐bubble and ACS injection, there were no adverse effects. A full‐scale prospective randomized study is feasible and warranted.     

Nonlinear models of chatter in drilling processes

We develop a nonlinear model of chatter in drilling that incorporates friction of the material on the cutting tool and its interaction with the axial-torsional mode of vibration seen in twist drills. Stability criteria are determined for both regenerative and non-regenerative chatter, and the effect of tool parameters and the friction law itself on the results is analysed. Our analysis shows that the exact form of the friction law is not critical in the stability calculation, only the size of the friction coefficient for steady cutting, and the slope of the friction law at the steady cutting state. However, its interaction with the geometry of the vibration is crucial. In the laboratory, drilling vibrational instabilities can occur at frequencies less than the natural frequency of the excited mode of the drill, and we find this result depends critically on the shape of the vibration mode projected onto the cutting edge of the drill.     

Memory-fast interfaces for DRAMs

The limitations of current nominal 5 V interfaces are examined, and the requirements for interfaces between high-speed DRAMs and processors are outlined. Three solutions are described. One is a center-tap-terminated interface, the second uses Gunning transceiver logic, and the third relies on low-voltage differential signaling