EEG-based usability assessment of 3D shutter glasses.

PubMed

Wenzel, Markus A; Schultze-Kraft, Rafael; Meinecke, Frank C; Fabien Cardinaux; Kemp, Thomas; Klaus-Robert Müller; Gabriel Curio; Benjamin Blankertz

2016-02-01

Neurotechnology can contribute to the usability assessment of products by providing objective measures of neural workload and can uncover usability impediments that are not consciously perceived by test persons. In this study, the neural processing effort imposed on the viewer of 3D television by shutter glasses was quantified as a function of shutter frequency. In particular, we sought to determine the critical shutter frequency at which the 'neural flicker' vanishes, such that visual fatigue due to this additional neural effort can be prevented by increasing the frequency of the system. Twenty-three participants viewed an image through 3D shutter glasses, while multichannel electroencephalogram (EEG) was recorded. In total ten shutter frequencies were employed, selected individually for each participant to cover the range below, at and above the threshold of flicker perception. The source of the neural flicker correlate was extracted using independent component analysis and the flicker impact on the visual cortex was quantified by decoding the state of the shutter from the EEG. Effects of the shutter glasses were traced in the EEG up to around 67 Hz-about 20 Hz over the flicker perception threshold-and vanished at the subsequent frequency level of 77 Hz. The impact of the shutter glasses on the visual cortex can be detected by neurotechnology even when a flicker is not reported by the participants. Potential impact. Increasing the shutter frequency from the usual 50 Hz or 60 Hz to 77 Hz reduces the risk of visual fatigue and thus improves shutter-glass-based 3D usability.

5 CFR 532.241 - Analysis of usable wage survey data.

Code of Federal Regulations, 2010 CFR

2010-01-01

... average rates identified and computed under paragraph (a) of this section. (ii) The frequency payline... PREVAILING RATE SYSTEMS Prevailing Rate Determinations § 532.241 Analysis of usable wage survey data. (a)(1) The lead agency shall compute a weighted average rate for each appropriated fund survey job having at...

Universally-Usable Interactive Electronic Physics Instructional And Educational Materials

NASA Astrophysics Data System (ADS)

Gardner, John

2000-03-01

Recent developments of technologies that promote full accessibility of electronic information by future generations of people with print disabilities will be described. ("Print disabilities" include low vision, blindness, and dyslexia.) The guiding philosophy of these developments is that information should be created and transmitted in a form that is as display-independent as possible, and that the user should have maximum freedom over how that information is to be displayed. This philosophy leads to maximum usability by everybody and is, in the long run, the only way to assure truly equal access. Research efforts to be described include access to mathematics and scientific notation and to graphs, tables, charts, diagrams, and general object-oriented graphics.

Analysis and Design of a Long Range PTFE Substrate UHF RFID Tag for Cargo Container Identification

NASA Astrophysics Data System (ADS)

Petrariu, Adrian-Ioan; Popa, Valentin

2016-01-01

In this paper, a high-performances microstrip antenna for UHF (ultra high frequency) RFID (radio frequency identification) tag is designed, prototyped and tested. The antenna consists of two main components: a 1.52 mm RT/duroid 5880 laminate substrate on which the antenna is designed and a 10 mm polytetrafluoroethylene (PTFE) dielectric material placed as a separator between the antenna and the reference ground plane for the microstrip antenna. With this structure, the RFID tag can reach a maximum reading distance of 19 m, although the antenna has a compact size of 80 mm × 50 mm. The long reading distance is obtained by attaching to the antenna an RFID chip that can provide a reading sensitivity of -20.5 dBm. The high bandwidth from 677 MHz to 947 MHz measured at -10 dB, makes the tag being usable worldwide especially for cargo container identification, the main purpose of this research.

Electric-drive tractability indicator integrated in hybrid electric vehicle tachometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tamai, Goro; Zhou, Jing; Weslati, Feisel

An indicator, system and method of indicating electric drive usability in a hybrid electric vehicle. A tachometer is used that includes a display having an all-electric drive portion and a hybrid drive portion. The all-electric drive portion and the hybrid drive portion share a first boundary which indicates a minimum electric drive usability and a beginning of hybrid drive operation of the vehicle. The indicated level of electric drive usability is derived from at least one of a percent battery discharge, a percent maximum torque provided by the electric drive, and a percent electric drive to hybrid drive operating costmore » for the hybrid electric vehicle.« less

Multifrequency measurements of core-diffracted P waves (Pdiff) for global waveform tomography

NASA Astrophysics Data System (ADS)

Hosseini, Kasra; Sigloch, Karin

2015-10-01

The lower third of the mantle is sampled extensively by body waves that diffract around the earth's core (Pdiff and Sdiff phases), which could deliver highly resolved tomographic images of this poorly understood region. But core-diffracted waves-especially Pdiff waves-are not often used in tomography because they are difficult to model adequately. Our aim is to make core-diffracted body waves usable for global waveform tomography, across their entire frequency range. Here we present the data processing part of this effort. A method is demonstrated that routinely calculates finite-frequency traveltimes of Pdiff waves by cross-correlating large quantities of waveform data with synthetic seismograms, in frequency passbands ranging from 30.0 to 2.7 s dominant period. Green's functions for 1857 earthquakes, typically comprising thousands of seismograms, are calculated by theoretically exact wave propagation through a spherically symmetric earth model, up to 1 Hz dominant period. Out of 418 226 candidates, 165 651 (39.6 per cent) source-receiver pairs yielded at least one successful passband measurement of a Pdiff traveltime anomaly, for a total of 479 559 traveltimes in the eight passbands considered. Measurements of teleseismic P waves yielded 448 178 usable source-receiver paths from 613 057 candidates (73.1 per cent success rate), for a total of 2 306 755 usable teleseismic dT in eight passbands. Observed and predicted characteristics of Pdiff traveltimes are discussed and compared to teleseismic P for this very large data set. Pdiff measurements are noise-limited due to severe wave attenuation with epicentral distance and frequency. Measurement success drops from 40-60 per cent at 80° distance, to 5-10 per cent at 140°. Frequency has a 2-3 times stronger influence on measurement success for Pdiff than for P. The fewest usable dT measurements are obtained in the microseismic noise band, whereas the fewest usable teleseismic P measurements occur at the highest frequencies. dT anomalies are larger for Pdiff than for P, and frequency dependence of dT due to 3-D heterogeneity (rather than just diffraction) is larger for Pdiff as well. Projecting the Pdiff traveltime anomalies on their core-grazing segments, we retrieve well-known, large-scale structural heterogeneities of the lowermost mantle, such as the two Large Low Shear Velocity Provinces, an Ultra-Low Velocity Zone west of Hawaii, and subducted slab accumulations under East Asia and Central America.

47 CFR 87.303 - Frequencies.

Code of Federal Regulations, 2010 CFR

2010-10-01

... telecommand operations for flight testing of aircraft and missiles, or their major components. The bands 2310... expendable and re-usable launch vehicles, whether or not such operations involve flight testing: 2364.5, 2370... Flight Test Stations § 87.303 Frequencies. (a) These frequencies are available for assignment to flight...

14 CFR 135.159 - Equipment requirements: Carrying passengers under VFR at night or under VFR over-the-top conditions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... chapter. (2) Helicopters with a third attitude instrument system usable through flight attitudes of ±80.... (3) Helicopters with a maximum certificated takeoff weight of 6,000 pounds or less. (b) A slip skid...) Notwithstanding provisions of paragraphs (b), (c), and (d), helicopters having a maximum certificated takeoff...

14 CFR 135.159 - Equipment requirements: Carrying passengers under VFR at night or under VFR over-the-top conditions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... chapter. (2) Helicopters with a third attitude instrument system usable through flight attitudes of ±80.... (3) Helicopters with a maximum certificated takeoff weight of 6,000 pounds or less. (b) A slip skid...) Notwithstanding provisions of paragraphs (b), (c), and (d), helicopters having a maximum certificated takeoff...

14 CFR 135.159 - Equipment requirements: Carrying passengers under VFR at night or under VFR over-the-top conditions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... chapter. (2) Helicopters with a third attitude instrument system usable through flight attitudes of ±80.... (3) Helicopters with a maximum certificated takeoff weight of 6,000 pounds or less. (b) A slip skid...) Notwithstanding provisions of paragraphs (b), (c), and (d), helicopters having a maximum certificated takeoff...

14 CFR 135.159 - Equipment requirements: Carrying passengers under VFR at night or under VFR over-the-top conditions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... chapter. (2) Helicopters with a third attitude instrument system usable through flight attitudes of ±80.... (3) Helicopters with a maximum certificated takeoff weight of 6,000 pounds or less. (b) A slip skid...) Notwithstanding provisions of paragraphs (b), (c), and (d), helicopters having a maximum certificated takeoff...

Usability evaluation of the interactive Personal Patient Profile-Prostate decision support system with African American men.

PubMed

Jaja, Cheedy; Pares-Avila, Jose; Wolpin, Seth; Berry, Donna

2010-04-01

The Personal Patient Profile-Prostate (P4) program is an interactive Web-based decision support system that provides men with localized prostate cancer customized education and coaching with which to make the best personal treatment decision. This study assessed functionality and usability of the P4 program and identified problems in user-computer interaction in a sample of African American men. Usability testing was conducted with 12 community-dwelling African American adult men. The health status of participants was not known or collected by the research team. Each participant worked with the P4 program and provided simultaneous feedback using the "think aloud" technique. Handwritten field notes were collated and assigned to 3 standard coded categories. Aspects of P4 program usability was made based on common issues in the assigned categories. Summary statistics were derived for types and frequency of usability issues noted in the coded data. Twelve participants reported a total of 122 usability comments, with a mean of 9 usability comments. The most common usability issue by participant was completeness of information content, which comprised 53 (43%) of the total issues. Comprehensibility of text and graphics was second, comprising 51 (42%) of the total issues. This study provided initial inventory of usability issues for community African American men that may potentially interfere with application of the P4 system in the community setting and overall system usability, confirming the need for usability testing of a culturally appropriate Internet-based decision support system before community application.

75 FR 78985 - County of DuPage; Notice of Preliminary Permit Application Accepted for Filing and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-17

... (upper reservoir) having a total storage capacity of 8,145 acre- feet at a normal maximum operating... reservoir) 250 feet below the bottom of the upper reservoir having a total/usable storage capacity of 7,465 acre-feet at normal maximum operation elevation of 210 feet msl; (5) a powerhouse with approximate...

Usability and feasibility of mobile phone diaries in an experimental physical exercise study.

PubMed

Heinonen, Reetta; Luoto, Riitta; Lindfors, Pirjo; Nygård, Clas-Håkan

2012-03-01

Wireless and mobile phone technology as a method of data collection will increase alongside conventional methods. The aim of the present study was to evaluate the use of a mobile phone application for recording symptoms and physical activity exertion during an experimental physical exercise study. An experimental study on the effects of physical exercise on the well-being of menopausal women included 158 subjects between 44 and 63 years of age. The women were randomized into intervention and control groups. All participants in both groups reported daily symptoms by responding to morning and evening questionnaires via mobile phones. The usability of the mobile phone as a data collector tool was evaluated with the System Usability Scale (SUS) questionnaire 2 months after the intervention. The feasibility evaluation was based on the frequency of responses and open questions. The response rates were about 70% to both morning and evening questionnaires. The average frequency of responses (n =158) to morning questionnaires was 125 (±40)/170 (±14) and to evening questionnaires was 118 (±40)/171 (±14). The response rate did not differ between the intervention and the control groups. The SUS score was on average 75.4 (range, 0-100; n =107). A mobile phone diary is a feasible and usable tool for data collection in clinical trials.

Performance in the vertical test of the 832 nine-cell 1.3 GHz cavities for the European X-ray Free Electron Laser

NASA Astrophysics Data System (ADS)

Reschke, D.; Gubarev, V.; Schaffran, J.; Steder, L.; Walker, N.; Wenskat, M.; Monaco, L.

2017-04-01

The successful production and associated vertical testing of over 800 superconducting 1.3 GHz accelerating cavities for the European X-ray Free Electron Laser (XFEL) represents the culmination of over 20 years of superconducting radio-frequency R&D. The cavity production took place at two industrial vendors under the shared responsibility of INFN Milano-LASA and DESY. Average vertical testing rates at DESY exceeded 10 cavities per week, peaking at up to 15 cavities per week. The cavities sent for cryomodule assembly at Commissariat à l'énergie atomique (CEA) Saclay achieved an average maximum gradient of approximately 33 MV /m , reducing to ˜30 MV /m when the operational specifications on quality factor (Q) and field emission were included (the so-called usable gradient). Only 16% of the cavities required an additional surface retreatment to recover their low performance (usable gradient less than 20 MV /m ). These cavities were predominantly limited by excessive field emission for which a simple high pressure water rinse (HPR) was sufficient. Approximately 16% of the cavities also received an additional HPR, e.g. due to vacuum problems before or during the tests or other reasons, but these were not directly related to gradient performance. The in-depth statistical analyses presented in this report have revealed several features of the series produced cavities.

The effect of sampling rate and anti-aliasing filters on high-frequency response spectra

USGS Publications Warehouse

Boore, David M.; Goulet, Christine

2013-01-01

The most commonly used intensity measure in ground-motion prediction equations is the pseudo-absolute response spectral acceleration (PSA), for response periods from 0.01 to 10 s (or frequencies from 0.1 to 100 Hz). PSAs are often derived from recorded ground motions, and these motions are usually filtered to remove high and low frequencies before the PSAs are computed. In this article we are only concerned with the removal of high frequencies. In modern digital recordings, this filtering corresponds at least to an anti-aliasing filter applied before conversion to digital values. Additional high-cut filtering is sometimes applied both to digital and to analog records to reduce high-frequency noise. Potential errors on the short-period (high-frequency) response spectral values are expected if the true ground motion has significant energy at frequencies above that of the anti-aliasing filter. This is especially important for areas where the instrumental sample rate and the associated anti-aliasing filter corner frequency (above which significant energy in the time series is removed) are low relative to the frequencies contained in the true ground motions. A ground-motion simulation study was conducted to investigate these effects and to develop guidance for defining the usable bandwidth for high-frequency PSA. The primary conclusion is that if the ratio of the maximum Fourier acceleration spectrum (FAS) to the FAS at a frequency fsaa corresponding to the start of the anti-aliasing filter is more than about 10, then PSA for frequencies above fsaa should be little affected by the recording process, because the ground-motion frequencies that control the response spectra will be less than fsaa . A second topic of this article concerns the resampling of the digital acceleration time series to a higher sample rate often used in the computation of short-period PSA. We confirm previous findings that sinc-function interpolation is preferred to the standard practice of using linear time interpolation for the resamplin

Responsive upper limb and cognitive fatigue measures during light precision work: an 8-hour simulated micro-pipetting study.

PubMed

Yung, Marcus; Wells, Richard P

2017-07-01

Many contemporary occupations are characterised by long periods of low loads. These lower force levels, which are relevant to the development of work-related musculoskeletal disorders, are usually not the focus of fatigue studies. In studies that did measure fatigue in light manual or precision work, within and between measurement responses were inconsistent. The aim of this study was to identify fatigue measures that were responsive at lower force levels (<10% MVC) over the course of an 8-h period. A complementary set of fatigue measures, reflecting both neuromuscular and cognitive mechanisms, was measured during a light precision micro-pipetting task performed by 11 participants. Nine measures were found to be significantly responsive over the 8-h period, including: ratings of perceived fatigue, postural tremor, blink frequency and critical flicker fusion frequency threshold. Common field measures, specifically electromyography RMS amplitude and maximum voluntary contractions, did not lead to extraordinary time effects. Practitioner summary: The findings provide insight towards the responsiveness of a complementary set of field usable fatigue measures at low work intensities Although commonly used measures did not reveal significant increases in fatigue, nine alternative measures were significantly responsive over the 8-h period.

A procedure for the reliability improvement of the oblique ionograms automatic scaling algorithm

NASA Astrophysics Data System (ADS)

Ippolito, Alessandro; Scotto, Carlo; Sabbagh, Dario; Sgrigna, Vittorio; Maher, Phillip

2016-05-01

A procedure made by the combined use of the Oblique Ionogram Automatic Scaling Algorithm (OIASA) and Autoscala program is presented. Using Martyn's equivalent path theorem, 384 oblique soundings from a high-quality data set have been converted into vertical ionograms and analyzed by Autoscala program. The ionograms pertain to the radio link between Curtin W.A. (CUR) and Alice Springs N.T. (MTE), Australia, geographical coordinates (17.60°S; 123.82°E) and (23.52°S; 133.68°E), respectively. The critical frequency foF2 values extracted from the converted vertical ionograms by Autoscala were then compared with the foF2 values derived from the maximum usable frequencies (MUFs) provided by OIASA. A quality factor Q for the MUF values autoscaled by OIASA has been identified. Q represents the difference between the foF2 value scaled by Autoscala from the converted vertical ionogram and the foF2 value obtained applying the secant law to the MUF provided by OIASA. Using the receiver operating characteristic curve, an appropriate threshold level Qt was chosen for Q to improve the performance of OIASA.

78 FR 66914 - Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-07

... upper reservoir having a total/usable storage capacity of 5,399 acre-feet at normal maximum operation... penstocks connecting the upper reservoir to the Pacific Ocean; (4) a 500-foot-long, 250-foot-diameter...

Factors associated with participation frequency and satisfaction among people applying for a housing adaptation grant.

PubMed

Thordardottir, Björg; Ekstam, Lisa; Chiatti, Carlos; Fänge, Agneta Malmgren

2016-09-01

People applying for a housing adaptation (HA) grant are at great risk of participation restrictions due to declining capacity and environmental barriers. To investigate the association of person-, environment-, and activity-related factors with participation frequency and satisfaction among people applying for a housing adaptation grant. Baseline cross-sectional data were collected during home visits (n = 128). The association between person-, environment-, and activity-related factors and participation frequency and satisfaction was analysed using logistic regressions. The main result is that frequency of participation outside the home is strongly associated with dependence in activities of daily living (ADL) and cognitive impairments, while satisfaction with participation outside the home is strongly associated with self-reported health. Moreover, aspects of usability in the home were associated with frequency of participation outside the home and satisfaction with participation in the home and outside the home alone. Dependence in ADL, cognitive impairments, self-rated health, and aspects of usability are important factors contributing to participation frequency and satisfaction among people applying for a housing adaptation grant, particularly outside the home. Our findings indicate that more attention should be directed towards activity-related factors to facilitate participation among HA applicants, inside and outside the home.

Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios

NASA Technical Reports Server (NTRS)

Barbosa Kortright, Miguel A.; Waldstein, Seth W.; Simons, Rainee N.

2017-01-01

An almost square patch, a square patch and a stacked square patch with corner truncation for circular polarization (CP) are researched and developed at X-band for cognitive radios. Experimental results indicate, first, that the impedance bandwidth of a CP almost square patch fed from the edge by a 50 ohm line is 1.70% and second, that of a CP square patch fed from the ground plane side by a surface launch connector is 1.87%. Third, the impedance bandwidth of a CP stacked square patch fed by a surface launch connector is 2.22%. The measured center frequency for the CP square patch fed by a surface launch connector without and with an identical stacked patch is 8.45 and 8.1017 GHz, respectively. By stacking a patch, separated by a fixed air gap of 0.254 mm, the center frequency is observed to shift by as much as 348.3 MHz. The shift in center frequency, brought about by the reconfiguring of the physical layer antenna, can be exploited in a cognitive system since it expands the usable frequency spectrum for software reconfiguration in the presence of interference. In addition, varying the fixed air gap in the stacked antenna geometry by increments of 0.254 mm further expands the usable frequency spectrum.

REAGENTLESS FIELD-USABLE FIXED-SITE AND PORTABLE ANALYZER FOR TRIHALOMETHANE (THM) CONCENTRATIONS IN DRINKING WATER - PHASE I

EPA Science Inventory

Environmental Protection Agency rules stipulate that corrective action be taken for drinking water distribution systems that exceed the maximum contaminant level (MCL) for total Trihalomethanes (TTHMs) 80μg/L.  Real-time, or even periodic, monitoring of drinking water i...

Design and Characterization of the UTIAS Anechoic Wind Tunnel

NASA Astrophysics Data System (ADS)

Chow, Derrick H. F.

The anechoic open-jet wind tunnel facility at the University of Toronto Institute for Aerospace Studies was updated and characterized to meet the needs of current and future aeroacoustic experiments. The wind tunnel inlet was resurfaced and flow-conditioning screens were redesigned to improve the freestream turbulence intensity to below 0.4% in the test section. The circular nozzle was replaced with a square secondary contraction that increased the maximum test section velocity to 75 m/s and improved flow uniformity to over 99% across a usable cross-sectional area of 500 mm x 500 mm. Acoustic baffles were installed in front of the wind tunnel inlet and foam wedges were installed in the anechoic chamber. The overall background sound pressure levels in the chamber were improved by 8-18 db over the range of operational freestream velocities. The anechoic chamber cut-off frequency is 170 Hz and the reverberation time for a 60 dB sound power decay is 0.032 s.

Operating manual-based usability evaluation of medical devices: an effective patient safety screening method.

PubMed

Turley, James P; Johnson, Todd R; Smith, Danielle Paige; Zhang, Jaijie; Brixey, Juliana J

2006-04-01

Use of medical devices often directly contributes to medical errors. Because it is difficult or impossible to change the design of existing devices, the best opportunity for improving medical device safety is during the purchasing process. However, most hospital personnel are not familiar with the usability evaluation methods designed to identify aspects of a user interface that do not support intuitive and safe use. A review of medical device operating manuals is proposed as a more practical method of usability evaluation. Operating manuals for five volumetric infusion pumps from three manufacturers were selected for this study (January-April 2003). Each manual's safety message content was evaluated to determine whether the message indicated a device design characteristic that violated known usability principles (heuristics) or indicated a violation of an affordance of the device. "Minimize memory load," with 65 violations, was the heuristic violated most frequently across pumps. Variations between pumps, including the frequency and severity of violations for each, were noted. Results suggest that manual review can provide a proxy for heuristic evaluation of the actual medical device. This method, intended to be a component of prepurchasing evaluation, can complement more formal usability evaluation methods and be used to select a subset of devices for more extensive and formal testing.

Physical habitat classification and instream flow modeling to determine habitat availability during low-flow periods, North Fork Shenandoah River, Virginia

USGS Publications Warehouse

Krstolic, Jennifer L.; Hayes, Donald C.; Ruhl, Peter M.

2006-01-01

Increasing development and increasing water withdrawals for public, industrial, and agricultural water supply threaten to reduce streamflows in the Shenandoah River basin in Virginia. Water managers need more information to balance human water-supply needs with the daily streamflows necessary for maintaining the aquatic ecosystems. To meet the need for comprehensive information on hydrology, water supply, and instream-flow requirements of the Shenandoah River basin, the U.S. Geological Survey and the Northern Shenandoah Valley Regional Commission conducted a cooperative investigation of habitat availability during low-flow periods on the North Fork Shenandoah River. Historic streamflow data and empirical data on physical habitat, river hydraulics, fish community structure, and recreation were used to develop a physical habitat simulation model. Hydraulic measurements were made during low, medium, and high flows in six reaches at a total of 36 transects that included riffles, runs, and pools, and that had a variety of substrates and cover types. Habitat suitability criteria for fish were developed from detailed fish-community sampling and microhabitat observations. Fish were grouped into four guilds of species and life stages with similar habitat requirements. Simulated habitat was considered in the context of seasonal flow regimes to show the availability of flows that sustain suitable habitat during months when precipitation and streamflow are scarce. The North Fork Shenandoah River basin was divided into three management sections for analysis purposes: the upper section, middle section, and lower section. The months of July, August, and September were chosen to represent a low-flow period in the basin with low mean monthly flows, low precipitation, high temperatures, and high water withdrawals. Exceedance flows calculated from the combined data from these three months describe low-flow periods on the North Fork Shenandoah River. Long-term records from three streamflow-gaging stations were used to characterize the flow regime: North Fork Shenandoah River at Cootes Store, Va. (1925-2002), North Fork Shenandoah River at Mount Jackson, Va. (1943-2002), and North Fork Shenandoah River near Strasburg, Va. (1925-2002). The predominant mesohabitat types (14 percent riffle, 67.3 percent run, and 18.7 percent pool) were classified along the entire river (100 miles) to assist in the selection of reaches for hydraulic and fish community data collection. The upper section has predominantly particle substrate, ranging in size from sand to boulders, and the shortest habitat units. The middle section is a transitional section with increased bedrock substrate and habitat unit length. The lower section has predominantly bedrock substrate and the longest habitat units in the river. The model simulations show that weighted usable-habitat area in the upper management section is highest at flows higher than the 25-percent exceedance flow for July, August, and September. During these three months, total weighted usable-habitat area in this section is often less than the simulated maximum weighted usable-habitat area. Habitat area in the middle management section is highest at flows between the 25- and 75-percent exceedance flows for July, August, and September. In the middle section during these months, both the actual weighted usable-habitat area and the simulated maximum weighted usable-habitat area are associated with this flow range. Weighted usable-habitat area in the lower management section is highest at flows lower than the 75-percent exceedance flow for July, August, and September. In the lower section during these three months, some weighted usable-habitat area is available, but the normal range of flows does not include the simulated maximum weighted usable-habitat area. A time-series habitat analysis associated with the historic streamflow, zero water withdrawals, and doubled water withdrawals was completed. During s

Application of small-size antennas for estimation of angles of arrival of HF signals scattered by ionospheric irregularities

NASA Astrophysics Data System (ADS)

Guo, Qiang; Galushko, Volodymyr G.; Zalizovski, Andriy V.; Kashcheyev, Sergiy B.; Zheng, Yu

2018-05-01

A modification of the Doppler Interferometry Technique is suggested to enable estimating angles of arrival of comparatively broadband HF signals scattered by random irregularities of the ionospheric plasma with the use of small-size weakly directional antennas. The technique is based on the measurements of cross-spectra phases of the probe radiation recorded at least in three spatially separated points. The developed algorithm has been used to investigate the angular and frequency-time characteristics of HF signals propagating at frequencies above the maximum usable one (MUF) for the direct radio path Moscow-Kharkiv. The received signal spectra show presence of three families of spatial components attributed, respectively, to scattering by plasma irregularities near the middle point of the radio path, ground backscatter signals and scattering of the sounding signals by the intense plasma turbulence associated with auroral activations. It has been shown that the regions responsible for the formation of the third family components are located well inside the auroral oval. The drift velocity and direction of the auroral ionosphere plasma have been determined. The obtained estimates are consistent with the classical conception of the ionospheric plasma convection at high latitudes and do not contradict the results of investigations of the auroral ionosphere dynamics using the SuperDARN network.

Multidither Adaptive Algorithms

DTIC Science & Technology

1976-09-01

Influence Function Profiles of Beryllium Mirror 32 11 Three-Dimensional View of Central-Actuator Influence for RADC Beryllium Mirror 33 12 Contour Lines...installed at this writing. Some preliminary tests on the mirror have determined its excur- sion sensitivity, influence function , and frequency...The frequency response shows some unusual resonance behavior, but is usable to at least 30 kHz. The 1 5 influence function has a shape given

Systematic Heuristic Evaluation of Computerized Consultation Order Templates: Clinicians' and Human Factors Engineers' Perspectives.

PubMed

Savoy, April; Patel, Himalaya; Flanagan, Mindy E; Weiner, Michael; Russ, Alissa L

2017-08-01

We assessed the usability of consultation order templates and identified problems to prioritize in design efforts for improving referral communication. With a sample of 26 consultation order templates, three evaluators performed a usability heuristic evaluation. The evaluation used 14 domain-independent heuristics and the following three supplemental references: 1 new domain-specific heuristic, 6 usability goals, and coded clinicians' statements regarding ease of use for 10 sampled templates. Evaluators found 201 violations, a mean of 7.7 violations per template. Minor violations outnumbered major violations almost twofold, 115 (57%) to 62 (31%). Approximately 68% of violations were linked to 5 heuristics: aesthetic and minimalist design (17%), error prevention (16%), consistency and standards (14%), recognition rather than recall (11%), and meet referrers' information needs (10%). Severe violations were attributed mostly to meet referrers' information needs and recognition rather than recall. Recorded violations yielded potential negative consequences for efficiency, effectiveness, safety, learnability, and utility. Evaluators and clinicians demonstrated 80% agreement in usability assessment. Based on frequency and severity of usability heuristic violations, the consultation order templates reviewed may impede clinical efficiency and risk patient safety. Results support the following design considerations: communicate consultants' requirements, facilitate information seeking, and support communication. While the most frequent heuristic violations involved interaction design and presentation, the most severe violations lacked information desired by referring clinicians. Violations related to templates' inability to support referring clinicians' information needs had the greatest potential negative impact on efficiency and safety usability goals. Heuristics should be prioritized in future design efforts.

Usability evaluation with mental health professionals and young people to develop an Internet-based cognitive-behaviour therapy program for adolescents with anxiety disorders.

PubMed

Wozney, Lori; Baxter, Pamela; Newton, Amanda S

2015-12-16

Use of the Internet to deliver cognitive behavioural therapy, a frontline treatment for anxiety disorders, is emerging as an option to increase access to treatment among adolescents with anxiety disorders. This study examined the usability of the Internet-based component of Breathe, a CBT program designed for adolescents with mild to moderate anxiety and impairments. A mixed-method usability testing design with semi-structured interviews, task completion, and survey by trained usability moderators was undertaken with two interactive cycles to determine the usability (ease of use, efficiency, errors, and user satisfaction) of the user interface and content areas of the program. Purposeful sampling was used to recruit mental health clinicians with expertise in treating adolescent anxiety disorders and young people aged 15 to 24 years involved. Testing involved using Web-conferencing software that allowed remote participation through personal computers. Two testing cycles involved participants completing structured 'think aloud' and 'cognitive walkthrough' tasks within the program. At the end of each cycle participants completed a 15-item global usability evaluation survey and were asked a series of open-ended questions. Descriptive and simple content analyses were used to identify and score usability issues for frequency and severity. Five clinicians and four young people (all < 20 years of age) participated. Most participants described their computer skills as 'good' (60% clinicians, 50% young people), and attitudes toward Internet-based health care ranged from negative (75% young people) to positive (60% clinicians, 25% young people). Scores from the global usability evaluation after both testing cycles ranged from 3.5 to 5 out of 5 in strong agreement/support of the program in terms of user performance indicators (i.e., learnability, efficiency and number of errors) and user satisfaction. Participants were able to complete all critical tasks with minimal errors. Errors and issues identified during testing were predominantly around enhancements to the visual design and navigational support. Opinions across usability elements did not differ between young people and clinician participants. A multi-method remote usability approach provided the opportunity to improve the technical interface, therapeutic messaging and user experience of an Internet-based treatment program for adolescent anxiety disorders.

Useful to Usable (U2U): Transforming climate information into usable tools to support Midwestern agricultural production

NASA Astrophysics Data System (ADS)

Prokopy, L. S.; Widhalm, M.

2014-12-01

There is a close connection between weather and climate patterns and successful agricultural production. Therefore, incorporating climate information into farm management is likely to reduce the risk of economic losses and increase profitability. While weather and climate information is becoming ever more abundant and accessible, the use of such information in the agricultural community remains limited. Useful to Usable (U2U): Transforming Climate Variability and Change Information for Cereal Crop Producers is a USDA-NIFA funded research and extension project focused on improving the use of climate information for agricultural production in the Midwestern United States by developing user-driven decision tools and training resources. The U2U team is a diverse and uniquely qualified group of climatologists, crop modelers, agronomists, and social scientists from 9 Midwestern universities and two NOAA Regional Climate Centers. Together, we strive to help producers make better long-term plans on what, when and where to plant and also how to manage crops for maximum yields and minimum environmental damage. To ensure relevance and usability of U2U products, our social science team is using a number of techniques including surveys and focus groups to integrate stakeholder interests, needs, and concerns into all aspects of U2U research. It is through this coupling of physical and social science disciplines that we strive to transform existing climate information into actionable knowledge.

Effects of tool handle dimension and workpiece orientation and size on wrist ulnar/radial torque strength, usability and discomfort in a wrench task.

PubMed

Dianat, Iman; Rahimi, Soleyman; Nedaei, Moein; Asghari Jafarabadi, Mohammad; Oskouei, Ali E

2017-03-01

The effects of tool handle dimension (three modified designs of wrenches with 30-50 mm diameter cylindrical handles and traditional design with rectangular cross-sectional (5 mm × 25 mm) handle), workpiece orientation (vertical/horizontal) and workpiece size (small/large) as well as user's hand size on wrist ulnar/radial (U/R) torque strength, usability and discomfort, and also the relationship between these variables were evaluated in a maximum torque task using wrenches. The highest and lowest levels of maximal wrist U/R torque strength were recorded for the 30 mm diameter handle and traditional wrench design, respectively. The prototype handle with 30 mm diameter, together with 40 mm diameter handle, was also better than other designs as they received higher usability ratings and caused less discomfort. The mean wrist torque strength exerted on a vertically oriented workpiece (in the sagittal plane) was 23.8% higher than that exerted on a horizontally oriented one (in the transverse plane). The user's hand size had no effect on torque exertions. The wrist torque strength and usability were negatively correlated with hand and finger discomfort ratings. The results are also discussed in terms of their implications for hand tool and workstation configuration in torque tasks involving wrenches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Unsupervised frequency-recognition method of SSVEPs using a filter bank implementation of binary subband CCA.

PubMed

Rabiul Islam, Md; Khademul Islam Molla, Md; Nakanishi, Masaki; Tanaka, Toshihisa

2017-04-01

Recently developed effective methods for detection commands of steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) that need calibration for visual stimuli, which cause more time and fatigue prior to the use, as the number of commands increases. This paper develops a novel unsupervised method based on canonical correlation analysis (CCA) for accurate detection of stimulus frequency. A novel unsupervised technique termed as binary subband CCA (BsCCA) is implemented in a multiband approach to enhance the frequency recognition performance of SSVEP. In BsCCA, two subbands are used and a CCA-based correlation coefficient is computed for the individual subbands. In addition, a reduced set of artificial reference signals is used to calculate CCA for the second subband. The analyzing SSVEP is decomposed into multiple subband and the BsCCA is implemented for each one. Then, the overall recognition score is determined by a weighted sum of the canonical correlation coefficients obtained from each band. A 12-class SSVEP dataset (frequency range: 9.25-14.75 Hz with an interval of 0.5 Hz) for ten healthy subjects are used to evaluate the performance of the proposed method. The results suggest that BsCCA significantly improves the performance of SSVEP-based BCI compared to the state-of-the-art methods. The proposed method is an unsupervised approach with averaged information transfer rate (ITR) of 77.04 bits min -1 across 10 subjects. The maximum individual ITR is 107.55 bits min -1 for 12-class SSVEP dataset, whereas, the ITR of 69.29 and 69.44 bits min -1 are achieved with CCA and NCCA respectively. The statistical test shows that the proposed unsupervised method significantly improves the performance of the SSVEP-based BCI. It can be usable in real world applications.

AC power generation from microbial fuel cells

NASA Astrophysics Data System (ADS)

Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

2015-11-01

Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

75 FR 73062 - Qualified Hydro 27, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-29

... (Howard A. Hanson project) to be located in King County, Washington, near the town of Palmer. The sole... 675-foot-long, 235-foot-high earth and rockfill Howard A. Hanson dam; (2) the existing Howard A. Hanson reservoir, which has a maximum usable storage of 106,000 acre-feet between elevation 1,206 feet...

Identification of task demands and usability issues in police use of mobile computing terminals.

PubMed

Zahabi, Maryam; Kaber, David

2018-01-01

Crash reports from various states in the U.S. have shown high numbers of emergency vehicle crashes, especially in law enforcement situations. This study identified the perceived importance and frequency of police mobile computing terminal (MCT) tasks, quantified the demands of different tasks using a cognitive performance modeling methodology, identified usability violations of current MCT interface designs, and formulated design recommendations for an enhanced interface. Results revealed that "access call notes", "plate number check" and "find location on map" are the most important and frequently performed tasks for officers. "Reading plate information" was also found to be the most visually and cognitively demanding task-method. Usability principles of "using simple and natural dialog" and "minimizing user memory load" were violated by the current MCT interface design. The enhanced design showed potential for reducing cognitive demands and task completion time. Findings should be further validated using a driving simulation study. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radio frequency (RF) microwave components and subsystems using loaded ridge waveguide

DOEpatents

Kang, Yoon W.

2013-08-20

A waveguide having a non-conductive material with a high permeability (.mu., .mu..sub.r for relative permeability) and/or a high permittivity (.di-elect cons., .di-elect cons..sub.r for relative permittivity) positioned within a housing. When compared to a hollow waveguide, the waveguide of this invention, reduces waveguide dimensions by .varies..mu. ##EQU00001## The waveguide of this invention further includes ridges which further reduce the size and increases the usable frequency bandwidth.

Modeling of HF propagation at high latitudes on the basis of IRI

NASA Astrophysics Data System (ADS)

Blagoveshchensky, D. V.; Maltseva, O. A.; Anishin, M. M.; Rogov, D. D.; Sergeeva, M. A.

2016-02-01

The paper presents the results of comparison between the modeling calculations and ionograms of oblique sounding for high-latitude HF radio paths of Arctic and Antarctic Research Institute (AARI), which was fulfilled for February 13-14, 2014 (quiet conditions). The International Reference Ionosphere 2012 model of the ionosphere (IRI-2012) was used for the study. The comparison results prove that without adaptation to current diagnostics the IRI model does not reflect the real state of high latitude ionosphere even for quiet conditions. It was found that in general the observed maximum usable frequency values (MUF) exceeded the same values obtained from the model. The adaptation of the model to current diagnostics makes the simulated MUF values significantly closer to the observed MUF. The following parameters were used for the study: critical frequencies foF2 measured by ionosondes located near the considered paths, frequencies calculated on the basis of observed TEC values and median values of the equivalent slab thickness of the ionosphere. The relative error of calculation of MUF values averaged for all the cases for one hop was 23.6% by the initial IRI model. This error was decreased by 4% for the calculations on the basis of observed ТЕС and by 6% for the adaptation to foF2. The higher the latitude of the studied radio path, the more the difference between the observed and simulated MUF values. The conclusion was made that a principal cause of this difference was the deviation of calculated maximum ionospheric height values (hmF2) from the observed hmF2. The additional model update using hmF2 values obtained from Tromso station let to better match between the calculated MUF values and the observed MUF values for all radio paths. The analysis of experimental data showed that the non-predicted events (like traveling ionospheric disturbances, M- and N-modes, lateral modes, triplets, unusual scatter effects, etc.) sometimes took place at high latitude paths even during the quiet conditions.

Formative usability evaluation of a fixed-dose pen-injector platform device

PubMed Central

Lange, Jakob; Nemeth, Tobias

2018-01-01

Background This article for the first time presents a formative usability study of a fixed-dose pen injector platform device used for the subcutaneous delivery of biopharmaceuticals, primarily for self-administration by the patient. The study was conducted with a user population of both naïve and experienced users across a range of ages. The goals of the study were to evaluate whether users could use the devices safely and effectively relying on the instructions for use (IFU) for guidance, as well as to benchmark the device against another similar injector established in the market. Further objectives were to capture any usability issues and obtain participants’ subjective ratings on the properties and performance of both devices. Methods A total of 20 participants in three groups studied the IFU and performed simulated injections into an injection pad. Results All participants were able to use the device successfully. The device was well appreciated by all users with, maximum usability feedback scores reported by 90% or more on handling forces and device feedback, and by 85% or more on fit and grip of the device. The presence of clear audible and visible feedbacks upon successful loading of a dose and completion of injection was seen to be a significant improvement over the benchmark injector. Conclusion The observation that the platform device can be safely and efficiently used by all user groups provides confidence that the device and IFU in their current form will pass future summative testing in specific applications. PMID:29670411

Improving the detectability and imaging capability of ground penetrating radar using novel antenna concepts

NASA Astrophysics Data System (ADS)

Koyadan Koroth, Ajith; Bhattacharya, Amitabha

2017-04-01

Antennas are key components of Ground Penetrating Radar (GPR) instrumentation. A carefully designed antenna can improve the detectability and imaging capability of a GPR to a great extent without changing the other instrumentations. In this work, we propose four different types of antennas for GPR. They are modifications of a conventional bowtie antenna with great improvement in performance parameters. The designed antennas has also been tested in a stepped frequency type GPR and two dimensional scan images of various targets are presented. Bowtie antennas have been traditionally employed in GPR for its wide impedance bandwidth and radiation properties. The researchers proposed resistive loading to improve the bandwidth of the bowtie antenna and for low ringing pulse radiation. But this method was detrimental for antenna gain and efficiency. Bowtie antennas have a very wide impedance bandwidth. But the useful bandwidth of the antenna has been limited by the radiation pattern bandwidth. The boresight gain of bowtie antennas are found to be unstable beyond a 4:1 bandwidth. In this work, these problems have been addressed and maximum usable bandwidth for the bowtie antennas has been achieved. In this work, four antennas have been designed: namely, 1.) RC loaded bowtie antennas, 2.) RC loaded bowtie with metamaterial lens, 3.) Loop loaded bowtie, 4.) Loop loaded bowtie with directors. The designed antennas were characterized for different parameters like impedance bandwidth, radiation pattern and, gain. In antenna 1, a combined resistive-capacitive loading has been applied by periodic slot cut on the arms of the bowtie and pasting a planar graphite sheet over it. Graphite having a less conductance compared to copper acts as resistive loading. This would minimize the losses compared to lumped resistive loading. The antenna had a 10:1 impedance bandwidth and, a 5:1 pattern bandwidth. In antenna 2, a metamaterial lens has been designed to augment the antenna 1, to improve the forward gain. This antenna had the same impedance bandwidth of 10:1 while pattern bandwidth has been raised to 7:1. In antenna 3, a loop loaded bowtie antenna has been designed. This antenna do not employ any kind of resistive loading, yet achieves an impedance bandwidth of 11:1 and also a usable bandwidth of 11:1. The antenna 4 employs concentric offset loops which acts as directors to improve the directivity. This antenna achieved an impedance bandwidth and a pattern bandwidth of 13:1. All the antennas have a maximum size of about 0.3λ at lowest operating frequency. An experimental stepped frequency type GPR has been constructed to study the suitability of the fabricated antennas in detecting buried targets. Four experiments have been conducted viz. 1.) To detect a metallic pipe of 1in diameter, 2.) To detect a metallic pipe of 2in diameter 3.) To detect dry bamboo, 3.) To detect rebar in concrete. The detectability and imaging capability of GPR has been found to be improving from antenna 1 to 4.

Usability Test of an Interactive Dietary Recording

ERIC Educational Resources Information Center

Chung, Louisa Ming Yan; Chung, Joanne Wai Yee; Wong, Thomas Kwok Shing

2009-01-01

Dietary intake methods are used to collect one's diet habit which is essential in nutrition assessment. Food diary, food frequency questionnaire (FFQ) and 24-hour recalls are the most common dietary intake methods. However, they are not welcomed by most clients. Digital handheld devices are now readily available, and the cost of digital…

Controller for a wave energy converter

DOEpatents

Wilson, David G.; Bull, Diana L.; Robinett, III, Rush D.

2015-09-22

A wave energy converter (WEC) is described, the WEC including a power take off (PTO) that converts relative motion of bodies of the WEC into electrical energy. A controller controls operation of the PTO, causing the PTO to act as a motor to widen a wave frequency spectrum that is usable to generate electrical energy.

High-current, high-frequency capacitors

NASA Technical Reports Server (NTRS)

Renz, D. D.

1983-01-01

The NASA Lewis high-current, high-frequency capacitor development program was conducted under a contract with Maxwell Laboratories, Inc., San Diego, California. The program was started to develop power components for space power systems. One of the components lacking was a high-power, high-frequency capacitor. Some of the technology developed in this program may be directly usable in an all-electric airplane. The materials used in the capacitor included the following: the film is polypropylene, the impregnant is monoisopropyl biphenyl, the conductive epoxy is Emerson and Cuming Stycast 2850 KT, the foil is aluminum, the case is stainless steel (304), and the electrode is a modified copper-ceramic.

Acceptance and usability of a home-based monitoring tool of health indicators in children of people with dementia: a Proof of Principle (POP) study.

PubMed

Boessen, April Bcg; Vermeulen, Joan; de Witte, Luc P

2017-01-01

Large-scale cohort studies are needed to confirm the relation between dementia and its possible risk factors. The inclusion of people with dementia in research is a challenge, however, children of people with dementia are at risk and are highly motivated to participate in dementia research. For technologies to support home-based data collection during large-scale studies, participants should be able and willing to use technology for a longer period of time. This study investigated acceptance and usability of iVitality, a research platform for home-based monitoring of dementia health indicators, in 151 children of people with dementia and investigated which frequency of measurements is acceptable for them. Participants were randomized to fortnightly or monthly measurements. At baseline and after 3 months, participants completed an online questionnaire regarding the acceptance (Technology Acceptance Model; 38 items) and usability (Post-Study System Usability Questionnaire; 24 items) of iVitality. Items were rated from 1 (I totally disagree) to 7 (I totally agree). Participants were also invited to take part in an online focus group (OFG) after 3 months of follow-up. Descriptive statistics and both two-sample/independent and paired t -tests were used to analyze the online questionnaires and a directed content analysis was used to analyze the OFGs. Children of people with dementia accept iVitality after long-term use and evaluate iVitality as a user-friendly, useful, and trusted technology, despite some suggestions for improvement. Overall, mean scores on acceptance and usability were higher than 5 (I somewhat agree), although the acceptance subscales "social influence" and "time" were rated somewhat lower. No significant differences in acceptance and usability were found between both protocol groups. Over time, "affect" significantly increased among participants measuring blood pressure fortnightly. iVitality has the potential to be used in large-scale studies for home-based monitoring of health indicators related to the development of dementia.

Cognitive engineering of film library transition from film medium to digital environment in a Texas teaching hospital.

PubMed

Koperwhats, Martha A; Chang, Wei-Chih; Xiao, Jianguo

2002-01-01

Digital imaging technology promises efficient, economical, and fast service for patient care, but the challenges are great in the transition from film to a filmless (digital) environment. This change has a significant impact on the film library's personnel (film librarians) who play a leading roles in storage, classification, and retrieval of images. The objectives of this project were to study film library errors and the usability of a physical computerized system that could not be changed, while developing an intervention to reduce errors and test the usability of the intervention. Cognitive and human factors analysis were used to evaluate human-computer interaction. A workflow analysis was performed to understand the film and digital imaging processes. User and task analyses were applied to account for all behaviors involved in interaction with the system. A heuristic evaluation was used to probe the usability issues in the picture archiving and communication systems (PACS) modules. Simplified paper-based instructions were designed to familiarize the film librarians with the digital system. A usability survey evaluated the effectiveness of the instruction. The user and task analyses indicated that different users faced challenges based on their computer literacy, education, roles, and frequency of use of diagnostic imaging. The workflow analysis showed that the approaches to using the digital library differ among the various departments. The heuristic evaluation of the PACS modules showed the human-computer interface to have usability issues that prevented easy operation. Simplified instructions were designed for operation of the modules. Usability surveys conducted before and after revision of the instructions showed that performance improved. Cognitive and human factor analysis can help film librarians and other users adapt to the filmless system. Use of cognitive science tools will aid in successful transition of the film library from a film environment to a digital environment.

Investigations into the feasibility of optical-CT 3D dosimetry with minimal use of refractively matched fluids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chisholm, Kelsey; Miles, Devin; Rankine, Leith

Purpose: In optical-CT, the use of a refractively matched polyurethane solid-tank in place of a fluid bath has the potential to greatly increase practical convenience, reduce cost, and possibly improve the efficacy of flood corrections. This work investigates the feasibility of solid-tank optical-CT imaging for 3D dosimetry through computer simulation. Methods: A MATLAB ray-tracing simulation platform, ScanSim, was used to model a parallel-source telecentric optical-CT imaging system through a polyurethane solid-tank containing a central cylindrical hollow into which PRESAGE radiochromic dosimeters can be placed. A small amount of fluid fills the 1–5 mm gap between the dosimeter and the wallsmore » of the tank. The use of the solid-tank reduces the required amount of fluid by approximately 97%. To characterize the efficacy of solid-tank, optical-CT scanning simulations investigated sensitivity to refractive index (RI) mismatches between dosimeter, solid-tank, and fluid, for a variety of dosimeter (RI = 1.5–1.47) and fluid (RI = 1.55–1.0) combinations. Efficacy was evaluated through the usable radius (r{sub u}) metric, defined as the fraction of the radius of the dosimeter where measured dose is predicted to be within 2% of the ground truth entered into the simulation. Additional simulations examined the effect of increasing gap size (1–5 mm) between the dosimeter and solid-tank well. The effects of changing the lens tolerance (0.5°–5.0°) were also investigated. Results: As the RI mismatch between the dosimeter and solid-tank increased from 0 to 0.02, the usable radius decreased from 97.6% to 50.2%. The optimal fluid RI decreased nonlinearly from 1.5 to 1.34 as the mismatch increased and was up to 9% lower than the tank. Media mismatches between the dosimeter and solid-tank also exacerbate the effects of changing the gap size, with no easily quantifiable relationship with usable radius. Generally, the optimal fluid RI value increases as gap size increases and is closely matched to the dosimeter at large gap sizes (>3 mm). Increasing the telecentric lens tolerance increases the usable radius for all refractive media combinations and improves the maximum usable radius of mismatched media to that of perfectly matched media for tolerances >5.0°. The maximum usable radius can be improved up to a factor of 2 when lens tolerances are small (<1.0°). Conclusions: Dry solid-tank optical-CT imaging in a telecentric system is feasible if the dosimeter RI is a close match with the solid-tank (<0.01 difference), providing accurate dose measurements within ±2% of true dose to over 80% of the dosimeter volume. In order to achieve accurate measurements over 96% of the dosimeter volume (representing out to 2 mm from the dosimeter edge), the dosimeter-tank RI mismatch must be less than 0.005. Optimal results occur when the RI of the dosimeter and tank is the same, in which case the fluid will have the same RI. If mismatches between the tank and dosimeter RI occur, the RI of the matching fluid needs to be fine tuned to achieve the highest usable radius.« less

Investigations into the feasibility of optical-CT 3D dosimetry with minimal use of refractively matched fluids.

PubMed

Chisholm, Kelsey; Miles, Devin; Rankine, Leith; Oldham, Mark

2015-05-01

In optical-CT, the use of a refractively matched polyurethane solid-tank in place of a fluid bath has the potential to greatly increase practical convenience, reduce cost, and possibly improve the efficacy of flood corrections. This work investigates the feasibility of solid-tank optical-CT imaging for 3D dosimetry through computer simulation. A matlab ray-tracing simulation platform, ScanSim, was used to model a parallel-source telecentric optical-CT imaging system through a polyurethane solid-tank containing a central cylindrical hollow into which PRESAGE radiochromic dosimeters can be placed. A small amount of fluid fills the 1-5 mm gap between the dosimeter and the walls of the tank. The use of the solid-tank reduces the required amount of fluid by approximately 97%. To characterize the efficacy of solid-tank, optical-CT scanning simulations investigated sensitivity to refractive index (RI) mismatches between dosimeter, solid-tank, and fluid, for a variety of dosimeter (RI = 1.5-1.47) and fluid (RI = 1.55-1.0) combinations. Efficacy was evaluated through the usable radius (ru) metric, defined as the fraction of the radius of the dosimeter where measured dose is predicted to be within 2% of the ground truth entered into the simulation. Additional simulations examined the effect of increasing gap size (1-5 mm) between the dosimeter and solid-tank well. The effects of changing the lens tolerance (0.5°-5.0°) were also investigated. As the RI mismatch between the dosimeter and solid-tank increased from 0 to 0.02, the usable radius decreased from 97.6% to 50.2%. The optimal fluid RI decreased nonlinearly from 1.5 to 1.34 as the mismatch increased and was up to 9% lower than the tank. Media mismatches between the dosimeter and solid-tank also exacerbate the effects of changing the gap size, with no easily quantifiable relationship with usable radius. Generally, the optimal fluid RI value increases as gap size increases and is closely matched to the dosimeter at large gap sizes (> 3 mm). Increasing the telecentric lens tolerance increases the usable radius for all refractive media combinations and improves the maximum usable radius of mismatched media to that of perfectly matched media for tolerances > 5.0°. The maximum usable radius can be improved up to a factor of 2 when lens tolerances are small (< 1.0°). Dry solid-tank optical-CT imaging in a telecentric system is feasible if the dosimeter RI is a close match with the solid-tank (< 0.01 difference), providing accurate dose measurements within ± 2% of true dose to over 80% of the dosimeter volume. In order to achieve accurate measurements over 96% of the dosimeter volume (representing out to 2 mm from the dosimeter edge), the dosimeter-tank RI mismatch must be less than 0.005. Optimal results occur when the RI of the dosimeter and tank is the same, in which case the fluid will have the same RI. If mismatches between the tank and dosimeter RI occur, the RI of the matching fluid needs to be fine tuned to achieve the highest usable radius.

Real-Time Support on IEEE 802.11 Wireless Ad-Hoc Networks: Reality vs. Theory

NASA Astrophysics Data System (ADS)

Kang, Mikyung; Kang, Dong-In; Suh, Jinwoo

The usable throughput of an IEEE 802.11 system for an application is much less than the raw bandwidth. Although 802.11b has a theoretical maximum of 11Mbps, more than half of the bandwidth is consumed by overhead leaving at most 5Mbps of usable bandwidth. Considering this characteristic, this paper proposes and analyzes a real-time distributed scheduling scheme based on the existing IEEE 802.11 wireless ad-hoc networks, using USC/ISI's Power Aware Sensing Tracking and Analysis (PASTA) hardware platform. We compared the distributed real-time scheduling scheme with the real-time polling scheme to meet deadline, and compared a measured real bandwidth with a theoretical result. The theoretical and experimental results show that the distributed scheduling scheme can guarantee real-time traffic and enhances the performance up to 74% compared with polling scheme.

Evaluating the usability of a virtual reality-based Android application in managing the pain experience of wheelchair users.

PubMed

Spyridonis, Fotios; Gronli, Tor-Morten; Hansen, Jarle; Ghinea, Gheorghita

2012-01-01

Pain constitutes an important medical concern that can have severe implications to a wheelchair user's quality of life. Results from studies indicate that pain is a common problem in this group of individuals, having a reported frequency of always (12%) and everyday (33%). This incidence signifies the need for more applicable and effective pain management clinical tools. As a result, in this paper we present an Android application (PainDroid) that has been enhanced with Virtual Reality (VR) technology for the purpose of improving the management of pain. Our evaluation with a group of wheelchair users revealed that PainDroid demonstrated high usability among this population, and is foreseen that it can make an important contribution in research on the assessment and management of pain.

Thermodynamic Properties of Fast Ramped Superconducting Accelerator Magnets for the Fair Project

NASA Astrophysics Data System (ADS)

Fischer, E.; Mierau, A.; Schnizer, P.; Bleile, A.; Gärtner, W.; Guymenuk, O.; Khodzhibagiyan, H.; Schroeder, C.; Sikler, G.; Stafiniak, A.

2010-04-01

The 100 Tm synchrotron SIS 100 is the core component of the international Facility of Antiproton and Ion Research (FAIR) to be built at GSI Darmstadt. The 108 bending magnets are 3 m long 2 T superferric dipoles providing a nominal ramp rate of 4 T/s within a usable aperture of 115 mmṡ60 mm. An intensive R&D period was conducted to minimise the AC losses to lower operation costs and to guarantee a safe thermal stability for long term continuous cycling with a maximum repetition frequency of 1 Hz. The latter requirement is strictly limited by the overall heat flow originated by eddy currents and hysteresis losses in iron yoke and coil as well as by its hydraulic resistance respective to the forced two phase helium cooling flow within the hollow superconducting cable. Recently three full size dipoles—and one quadrupole magnets were built and intensive tests have been started in the end of 2008 at the GSI cryogenic test facility. We present the measured thermodynamic parameters of the first tested dipole: AC losses depending on Bmax and dB/dt for various characteristic ramping modes and conclude for necessary optimisations toward the final design of the series magnets.

Real-Time Processing Library for Open-Source Hardware Biomedical Sensors

PubMed Central

Castro-García, Juan A.; Lebrato-Vázquez, Clara

2018-01-01

Applications involving data acquisition from sensors need samples at a preset frequency rate, the filtering out of noise and/or analysis of certain frequency components. We propose a novel software architecture based on open-software hardware platforms which allows programmers to create data streams from input channels and easily implement filters and frequency analysis objects. The performances of the different classes given in the size of memory allocated and execution time (number of clock cycles) were analyzed in the low-cost platform Arduino Genuino. In addition, 11 people took part in an experiment in which they had to implement several exercises and complete a usability test. Sampling rates under 250 Hz (typical for many biomedical applications) makes it feasible to implement filters, sliding windows and Fourier analysis, operating in real time. Participants rated software usability at 70.2 out of 100 and the ease of use when implementing several signal processing applications was rated at just over 4.4 out of 5. Participants showed their intention of using this software because it was percieved as useful and very easy to use. The performances of the library showed that it may be appropriate for implementing small biomedical real-time applications or for human movement monitoring, even in a simple open-source hardware device like Arduino Genuino. The general perception about this library is that it is easy to use and intuitive. PMID:29596394

Real-Time Processing Library for Open-Source Hardware Biomedical Sensors.

PubMed

Molina-Cantero, Alberto J; Castro-García, Juan A; Lebrato-Vázquez, Clara; Gómez-González, Isabel M; Merino-Monge, Manuel

2018-03-29

Applications involving data acquisition from sensors need samples at a preset frequency rate, the filtering out of noise and/or analysis of certain frequency components. We propose a novel software architecture based on open-software hardware platforms which allows programmers to create data streams from input channels and easily implement filters and frequency analysis objects. The performances of the different classes given in the size of memory allocated and execution time (number of clock cycles) were analyzed in the low-cost platform Arduino Genuino. In addition, 11 people took part in an experiment in which they had to implement several exercises and complete a usability test. Sampling rates under 250 Hz (typical for many biomedical applications) makes it feasible to implement filters, sliding windows and Fourier analysis, operating in real time. Participants rated software usability at 70.2 out of 100 and the ease of use when implementing several signal processing applications was rated at just over 4.4 out of 5. Participants showed their intention of using this software because it was percieved as useful and very easy to use. The performances of the library showed that it may be appropriate for implementing small biomedical real-time applications or for human movement monitoring, even in a simple open-source hardware device like Arduino Genuino. The general perception about this library is that it is easy to use and intuitive.

Variable frequency iteration MPPT for resonant power converters

DOEpatents

Zhang, Qian; Bataresh, Issa; Chen, Lin

2015-06-30

A method of maximum power point tracking (MPPT) uses an MPPT algorithm to determine a switching frequency for a resonant power converter, including initializing by setting an initial boundary frequency range that is divided into initial frequency sub-ranges bounded by initial frequencies including an initial center frequency and first and second initial bounding frequencies. A first iteration includes measuring initial powers at the initial frequencies to determine a maximum power initial frequency that is used to set a first reduced frequency search range centered or bounded by the maximum power initial frequency including at least a first additional bounding frequency. A second iteration includes calculating first and second center frequencies by averaging adjacent frequent values in the first reduced frequency search range and measuring second power values at the first and second center frequencies. The switching frequency is determined from measured power values including the second power values.

Mobile applications for diabetics: a systematic review and expert-based usability evaluation considering the special requirements of diabetes patients age 50 years or older.

PubMed

Arnhold, Madlen; Quade, Mandy; Kirch, Wilhelm

2014-04-09

A multitude of mhealth (mobile health) apps have been developed in recent years to support effective self-management of patients with diabetes mellitus type 1 or 2. We carried out a systematic review of all currently available diabetes apps for the operating systems iOS and Android. We considered the number of newly released diabetes apps, range of functions, target user groups, languages, acquisition costs, user ratings, available interfaces, and the connection between acquisition costs and user ratings. Additionally, we examined whether the available applications serve the special needs of diabetes patients aged 50 or older by performing an expert-based usability evaluation. We identified relevant keywords, comparative categories, and their specifications. Subsequently, we performed the app review based on the information given in the Google Play Store, the Apple App Store, and the apps themselves. In addition, we carried out an expert-based usability evaluation based on a representative 10% sample of diabetes apps. In total, we analyzed 656 apps finding that 355 (54.1%) offered just one function and 348 (53.0%) provided a documentation function. The dominating app language was English (85.4%, 560/656), patients represented the main user group (96.0%, 630/656), and the analysis of the costs revealed a trend toward free apps (53.7%, 352/656). The median price of paid apps was €1.90. The average user rating was 3.6 stars (maximum 5). Our analyses indicated no clear differences in the user rating between free and paid apps. Only 30 (4.6%) of the 656 available diabetes apps offered an interface to a measurement device. We evaluated 66 apps within the usability evaluation. On average, apps were rated best regarding the criterion "comprehensibility" (4.0 out of 5.0), while showing a lack of "fault tolerance" (2.8 out of 5.0). Of the 66 apps, 48 (72.7%) offered the ability to read the screen content aloud. The number of functions was significantly negative correlated with usability. The presence of documentation and analysis functions reduced the usability score significantly by 0.36 and 0.21 points. A vast number of diabetes apps already exist, but the majority offer similar functionalities and combine only one to two functions in one app. Patients and physicians alike should be involved in the app development process to a greater extent. We expect that the data transmission of health parameters to physicians will gain more importance in future applications. The usability of diabetes apps for patients aged 50 or older was moderate to good. But this result applied mainly to apps offering a small range of functions. Multifunctional apps performed considerably worse in terms of usability. Moreover, the presence of a documentation or analysis function resulted in significantly lower usability scores. The operability of accessibility features for diabetes apps was quite limited, except for the feature "screen reader".

Unsupervised frequency-recognition method of SSVEPs using a filter bank implementation of binary subband CCA

NASA Astrophysics Data System (ADS)

Rabiul Islam, Md; Khademul Islam Molla, Md; Nakanishi, Masaki; Tanaka, Toshihisa

2017-04-01

Objective. Recently developed effective methods for detection commands of steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) that need calibration for visual stimuli, which cause more time and fatigue prior to the use, as the number of commands increases. This paper develops a novel unsupervised method based on canonical correlation analysis (CCA) for accurate detection of stimulus frequency. Approach. A novel unsupervised technique termed as binary subband CCA (BsCCA) is implemented in a multiband approach to enhance the frequency recognition performance of SSVEP. In BsCCA, two subbands are used and a CCA-based correlation coefficient is computed for the individual subbands. In addition, a reduced set of artificial reference signals is used to calculate CCA for the second subband. The analyzing SSVEP is decomposed into multiple subband and the BsCCA is implemented for each one. Then, the overall recognition score is determined by a weighted sum of the canonical correlation coefficients obtained from each band. Main results. A 12-class SSVEP dataset (frequency range: 9.25-14.75 Hz with an interval of 0.5 Hz) for ten healthy subjects are used to evaluate the performance of the proposed method. The results suggest that BsCCA significantly improves the performance of SSVEP-based BCI compared to the state-of-the-art methods. The proposed method is an unsupervised approach with averaged information transfer rate (ITR) of 77.04 bits min-1 across 10 subjects. The maximum individual ITR is 107.55 bits min-1 for 12-class SSVEP dataset, whereas, the ITR of 69.29 and 69.44 bits min-1 are achieved with CCA and NCCA respectively. Significance. The statistical test shows that the proposed unsupervised method significantly improves the performance of the SSVEP-based BCI. It can be usable in real world applications.

Validation of High Frequency (HF) Propagation Prediction Models in the Arctic region

NASA Astrophysics Data System (ADS)

Athieno, R.; Jayachandran, P. T.

2014-12-01

Despite the emergence of modern techniques for long distance communication, Ionospheric communication in the high frequency (HF) band (3-30 MHz) remains significant to both civilian and military users. However, the efficient use of the ever-varying ionosphere as a propagation medium is dependent on the reliability of ionospheric and HF propagation prediction models. Most available models are empirical implying that data collection has to be sufficiently large to provide good intended results. The models we present were developed with little data from the high latitudes which necessitates their validation. This paper presents the validation of three long term High Frequency (HF) propagation prediction models over a path within the Arctic region. Measurements of the Maximum Usable Frequency for a 3000 km range (MUF (3000) F2) for Resolute, Canada (74.75° N, 265.00° E), are obtained from hand-scaled ionograms generated by the Canadian Advanced Digital Ionosonde (CADI). The observations have been compared with predictions obtained from the Ionospheric Communication Enhanced Profile Analysis Program (ICEPAC), Voice of America Coverage Analysis Program (VOACAP) and International Telecommunication Union Recommendation 533 (ITU-REC533) for 2009, 2011, 2012 and 2013. A statistical analysis shows that the monthly predictions seem to reproduce the general features of the observations throughout the year though it is more evident in the winter and equinox months. Both predictions and observations show a diurnal and seasonal variation. The analysed models did not show large differences in their performances. However, there are noticeable differences across seasons for the entire period analysed: REC533 gives a better performance in winter months while VOACAP has a better performance for both equinox and summer months. VOACAP gives a better performance in the daily predictions compared to ICEPAC though, in general, the monthly predictions seem to agree more with the observations compared to the daily predictions.

Usability of Computerized Lung Auscultation-Sound Software (CLASS) for learning pulmonary auscultation.

PubMed

Machado, Ana; Oliveira, Ana; Jácome, Cristina; Pereira, Marco; Moreira, José; Rodrigues, João; Aparício, José; Jesus, Luis M T; Marques, Alda

2018-04-01

The mastering of pulmonary auscultation requires complex acoustic skills. Computer-assisted learning tools (CALTs) have potential to enhance the learning of these skills; however, few have been developed for this purpose and do not integrate all the required features. Thus, this study aimed to assess the usability of a new CALT for learning pulmonary auscultation. Computerized Lung Auscultation-Sound Software (CLASS) usability was assessed by eight physiotherapy students using computer screen recordings, think-aloud reports, and facial expressions. Time spent in each task, frequency of messages and facial expressions, number of clicks and problems reported were counted. The timelines of the three methods used were matched/synchronized and analyzed. The tasks exercises and annotation of respiratory sounds were the ones requiring more clicks (median 132, interquartile range [23-157]; 93 [53-155]; 91 [65-104], respectively) and where most errors (19; 37; 15%, respectively) and problems (n = 7; 6; 3, respectively) were reported. Each participant reported a median of 6 problems, with a total of 14 different problems found, mainly related with CLASS functionalities (50%). Smile was the only facial expression presented in all tasks (n = 54). CLASS is the only CALT available that meets all the required features for learning pulmonary auscultation. The combination of the three usability methods identified advantages/disadvantages of CLASS and offered guidance for future developments, namely in annotations and exercises. This will allow the improvement of CLASS and enhance students' activities for learning pulmonary auscultation skills.

Use of Online Machine Translation for Nursing Literature: A Questionnaire-Based Survey

PubMed Central

Anazawa, Ryoko; Ishikawa, Hirono; Takahiro, Kiuchi

2013-01-01

Background: The language barrier is a significant obstacle for nurses who are not native English speakers to obtain information from international journals. Freely accessible online machine translation (MT) offers a possible solution to this problem. Aim: To explore how Japanese nursing professionals use online MT and perceive its usability in reading English articles and to discuss what should be considered for better utilisation of online MT lessening the language barrier. Method: In total, 250 randomly selected assistants and research associates at nursing colleges across Japan answered a questionnaire examining the current use of online MT and perceived usability among Japanese nurses, along with the number of articles read in English and the perceived language barrier. The items were rated on Likert scales, and t-test, ANOVA, chi-square test, and Spearman’s correlation were used for analyses. Results: Of the participants, 73.8% had used online MT. More than half of them felt it was usable. The language barrier was strongly felt, and academic degrees and English proficiency level were associated factors. The perceived language barrier was related to the frequency of online MT use. No associated factor was found for the perceived usability of online MT. Conclusion: Language proficiency is an important factor for optimum utilisation of MT. A need for education in the English language, reading scientific papers, and online MT training was indicated. Cooperation with developers and providers of MT for the improvement of their systems is required. PMID:23459140

The Usability Evaluation of Fakih Method Based on Technology for Students with Hearing Difficulties: The User's Retrospective

ERIC Educational Resources Information Center

Sabdan, Muhammad Sayuti Bin; Alias, Norlidah; Jomhari, Nazean; Jamaludin, Khairul Azhar; DeWitt, Dorothy

2014-01-01

The study is aimed at evaluating the FAKIH method based on technology in teaching al-Quran, based on the user's retrospective. The participants of this study were five students selected based on hearing difficulties. The study employed the user evaluation framework. Teacher's journals were used to determine the frequency and percentage of…

Design guidelines for interactive multimedia learning environments to promote social inclusion.

PubMed

Brown, D J; Powell, H M; Battersby, S; Lewis, J; Shopland, N; Yazdanparast, M

There is a continuing need for guidelines to aid in the design of Interactive Multimedia Learning Environments (IMLE) to promote effective learning. The project introduced in this paper looks at an important subset of this problem, the design of interactive learning environments to promote social inclusion. A consortium of six partners contributed toward defining learning material to develop a range of work based skills, including horticulture, IT and catering. These were then developed into IMLE prototypes. Formative evaluation of these prototypes then revealed a range of usability problems, which were grouped into generic types and frequency of occurrence. The most important and frequently occurring problems were used to distil a set of design guidelines for the development of effective IMLE. The results from this usability content analysis were also used to refine the initial prototypes to improve their usability and effectiveness. These guidelines, termed the Greenhat Design Guidelines, can be adopted for use by all multimedia developers aiming to promote the social inclusion of vulnerable or socially disadvantaged groups of people. The refined IMLE can be accessed via the Greenhat Server to improve the employment-related skills of socially excluded people.

Estimating usable resources from historical industry data

USGS Publications Warehouse

Cargill, S.M.; Root, D.H.; Bailey, E.H.

1981-01-01

Historical production statistics are used to predict the quantity of remaining usable resources. The commodities considered are mercury, copper and its byproducts gold and silver, and petroleum; the production and discovery data are for the United States. The results of the study indicate that the cumulative return per unit of effort, herein measured as grade of metal ores and discovery rate of recoverable petroleum, is proportional to a negative power of total effort expended, herein measured as total ore mined and total exploratory wells or footage drilled. This power relationship can be extended to some limiting point (a lower ore grade or a maximum number of exploratory wells or footage), and the apparent quantity of available remaining resource at that limit can be calculated. For mercury ore of grades at and above 0.1 percent, the remaining usable resource in the United States is calculated to be 54 million kg (1,567,000 flasks). For copper ore of grades at and above 0.2 percent, the remaining usable copper resource is calculated to be 270 million metric tons (298 million short tons); remaining resources of its by-products gold and silver are calculated to be 3,656 metric tons (118 million troy ounces) and 64,676 metric tons (2,079 million troy ounces), respectively. The undiscovered recoverable crude oil resource in the conterminous United States, at 3 billion feet of additional exploratory drilling, is calculated to be nearly 37.6 billion barrels; the undiscovered recoverable petroleum resource in the Permian basin of western Texas and southeastern New Mexico, at 300 million feet of additional exploratory drilling or 50,000 additional exploratory wells, is calculated to be about 6.2 billion BOE (barrels of oil equivalent).

Evaluating a Pivot-Based Approach for Bilingual Lexicon Extraction

PubMed Central

Kim, Jae-Hoon; Kwon, Hong-Seok; Seo, Hyeong-Won

2015-01-01

A pivot-based approach for bilingual lexicon extraction is based on the similarity of context vectors represented by words in a pivot language like English. In this paper, in order to show validity and usability of the pivot-based approach, we evaluate the approach in company with two different methods for estimating context vectors: one estimates them from two parallel corpora based on word association between source words (resp., target words) and pivot words and the other estimates them from two parallel corpora based on word alignment tools for statistical machine translation. Empirical results on two language pairs (e.g., Korean-Spanish and Korean-French) have shown that the pivot-based approach is very promising for resource-poor languages and this approach observes its validity and usability. Furthermore, for words with low frequency, our method is also well performed. PMID:25983745

47 CFR 90.377 - Frequencies available; maximum EIRP and antenna height, and priority communications.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Frequencies available; maximum EIRP and antenna...; maximum EIRP and antenna height, and priority communications. (a) Licensees shall transmit only the power... maximum EIRP permitted for an RSU with an antenna height not exceeding 8 meters above the roadway bed...

47 CFR 90.377 - Frequencies available; maximum EIRP and antenna height, and priority communications.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Frequencies available; maximum EIRP and antenna...; maximum EIRP and antenna height, and priority communications. (a) Licensees shall transmit only the power... maximum EIRP permitted for an RSU with an antenna height not exceeding 8 meters above the roadway bed...

47 CFR 90.377 - Frequencies available; maximum EIRP and antenna height, and priority communications.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Frequencies available; maximum EIRP and antenna...; maximum EIRP and antenna height, and priority communications. (a) Licensees shall transmit only the power... maximum EIRP permitted for an RSU with an antenna height not exceeding 8 meters above the roadway bed...

47 CFR 90.377 - Frequencies available; maximum EIRP and antenna height, and priority communications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies available; maximum EIRP and antenna...; maximum EIRP and antenna height, and priority communications. (a) Licensees shall transmit only the power... maximum EIRP permitted for an RSU with an antenna height not exceeding 8 meters above the roadway bed...

Testing of an Annular Linear Induction Pump for the Fission Surface Power Technology Demonstration Unit

NASA Technical Reports Server (NTRS)

Polzin, K. A.; Pearson, J. B.; Webster, K.; Godfoy, T. J.; Bossard, J. A.

2013-01-01

Results of performance testing of an annular linear induction pump that has been designed for integration into a fission surface power technology demonstration unit are presented. The pump electromagnetically pushes liquid metal (NaK) through a specially-designed apparatus that permits quantification of pump performance over a range of operating conditions. Testing was conducted for frequencies of 40, 55, and 70 Hz, liquid metal temperatures of 125, 325, and 525 C, and input voltages from 30 to 120 V. Pump performance spanned a range of flow rates from roughly 0.3 to 3.1 L/s (4.8 to 49 gpm), and pressure heads of <1 to 104 kPa (<0.15 to 15 psi). The maximum efficiency measured during testing was 5.4%. At the technology demonstration unit operating temperature of 525 C the pump operated over a narrower envelope, with flow rates from 0.3 to 2.75 L/s (4.8 to 43.6 gpm), developed pressure heads from <1 to 55 kPa (<0.15 to 8 psi), and a maximum efficiency of 3.5%. The pump was supplied with three-phase power at 40 and 55 Hz using a variable-frequency motor drive, while power at 55 and 70 Hz was supplied using a variable-frequency power supply. Measured performance of the pump at 55 Hz using either supply exhibited good quantitative agreement. For a given temperature, the peak in efficiency occurred at different flow rates as the frequency was changed, but the maximum value of efficiency was relative insensitive within 0.3% over the frequency range tested, including a scan from 45 to 78 Hz. The objectives of the FSP technology project are as follows:5 • Develop FSP concepts that meet expected surface power requirements at reasonable cost with added benefits over other options. • Establish a nonnuclear hardware-based technical foundation for FSP design concepts to reduce overall development risk. • Reduce the cost uncertainties for FSP and establish greater credibility for flight system cost estimates. • Generate the key nonnuclear products to allow Agency decision makers to consider FSP as a viable option for potential future flight development. The pump must be compatible with the liquid NaK coolant and have adequate performance to enable a viable flight system. Idaho National Laboratory (INL) was tasked with the design and fabrication of an ALIP suitable for the FSP reference mission. Under the program, a quarter-scale FSP technology demonstration is under construction to test the end-to-end conversion of simulated nuclear thermal power to usable electrical power intended to raise the entire FSP system to Technology Readiness Level 6. An ALIP for this TDU was fabricated under the direction of the INL and shipped to NASA Marshall Space Flight Center (MSFC) for testing at representative operating conditions. This pump was designed to meet the requirements of the TDU experiment. The ALIP test circuit (ATC) at MSFC, previously used to conduct performance evaluation on another ALIP6 was used to test the present TDU pump for the FSP Technology Development program.

Acceptance and usability of a home-based monitoring tool of health indicators in children of people with dementia: a Proof of Principle (POP) study

PubMed Central

Boessen, April BCG; Vermeulen, Joan; de Witte, Luc P

2017-01-01

Background Large-scale cohort studies are needed to confirm the relation between dementia and its possible risk factors. The inclusion of people with dementia in research is a challenge, however, children of people with dementia are at risk and are highly motivated to participate in dementia research. For technologies to support home-based data collection during large-scale studies, participants should be able and willing to use technology for a longer period of time. Objective This study investigated acceptance and usability of iVitality, a research platform for home-based monitoring of dementia health indicators, in 151 children of people with dementia and investigated which frequency of measurements is acceptable for them. Methods Participants were randomized to fortnightly or monthly measurements. At baseline and after 3 months, participants completed an online questionnaire regarding the acceptance (Technology Acceptance Model; 38 items) and usability (Post-Study System Usability Questionnaire; 24 items) of iVitality. Items were rated from 1 (I totally disagree) to 7 (I totally agree). Participants were also invited to take part in an online focus group (OFG) after 3 months of follow-up. Descriptive statistics and both two-sample/independent and paired t-tests were used to analyze the online questionnaires and a directed content analysis was used to analyze the OFGs. Results Children of people with dementia accept iVitality after long-term use and evaluate iVitality as a user-friendly, useful, and trusted technology, despite some suggestions for improvement. Overall, mean scores on acceptance and usability were higher than 5 (I somewhat agree), although the acceptance subscales “social influence” and “time” were rated somewhat lower. No significant differences in acceptance and usability were found between both protocol groups. Over time, “affect” significantly increased among participants measuring blood pressure fortnightly. Conclusion iVitality has the potential to be used in large-scale studies for home-based monitoring of health indicators related to the development of dementia. PMID:28814839

4-fluoroalkyl-3-halophenyl nortropanes

DOEpatents

Goodman, Mark M.; Chen, Ping

2002-06-04

A series of compounds in the 4-fluoroalkyl-3-halophenyl nortropanes family are described as diagnostic and therapeutic agents for diseases associated with serotonin transporter dysfunction. These compounds bind to serotonin transporter protein with high affinity and selectivity. The invention provides methods of synthesis which incorporate radioisotopic halogens at a last step which permit high radiochemical yield and maximum usable product life. The radiolabeled compounds of the invention are useful as imaging agents for visualizing the location and density of serotonin transporter by PET and SPECT imaging.

What patients' problems do nurses e-chart? Longitudinal study to evaluate the usability of an interface terminology.

PubMed

Juvé-Udina, Maria Eulàlia

2013-12-01

The nurses' ability to document patient's status, problems and progress is an important issue in patients' safety. Nursing terminologies are intended to support nursing practice but as any other clinical tool, they should be evaluated to assure quality and warrant effective written communication among clinicians. This study was aimed to evaluate the usability of the diagnosis axis of an interface terminology by assessing its completeness and the frequency of use of its concepts. Observational, longitudinal, multicentre study. A total of 8 hospitals representing 162 acute medical-surgical, obstetric and mental health nursing wards, step-down units and home in-patient units were included. Overall, 246,400 electronic care plans were studied; 53.5% from male patients; 14.6% paediatrics and 33.7% from patients elder than 70 years old. Most were admitted due to cardiocirculatory, respiratory, digestive or musculoskeletal conditions (50.5%), other acute medical or surgical disorders (29.8%) and obstetrics (19.3%). The main outcome measures were: the use of nursing diagnoses from the interface terminology evaluated and their accumulated frequency, analysed over a 3-year retrospective review of the electronic nursing care plans. The analysis of data included descriptive statistics with a confidence level of 95% for confidence intervals. Most of the diagnostic concepts from the interface terminology were used (92.3%) by nurses to illustrate patients' problems in the electronic care plans. Their frequency of use widely varied, from some very frequent diagnoses like Risk for haemorrhage (51.4%; CI 95%: 51.25-51.65) or Acute pain (49.6%; CI: 49.49-49.88) to others used only in exceptional cases like Faecal impaction or Extravasation. The first nursing diagnosis related to family or caregiver emerges in the 32nd place of the ranking. Results for outcome measures oriented that the diagnosis axis of this interface terminology meets the usability criterion of completeness when assessing for the use of its concepts in the acute care setting. Copyright © 2013 Elsevier Ltd. All rights reserved.

Management of surgical instruments with radio frequency identification tags.

PubMed

Kusuda, Kaori; Yamashita, Kazuhiko; Ohnishi, Akiko; Tanaka, Kiyohito; Komino, Masaru; Honda, Hiroshi; Tanaka, Shinichi; Okubo, Takashi; Tripette, Julien; Ohta, Yuji

2016-01-01

To prevent malpractices, medical staff has adopted inventory time-outs and/or checklists. Accurate inventory and maintenance of surgical instruments decreases the risk of operating room miscounting and malfunction. In our previous study, an individual management of surgical instruments was accomplished using Radio Frequency Identification (RFID) tags. The purpose of this paper is to evaluate a new management method of RFID-tagged instruments. The management system of RFID-tagged surgical instruments was used for 27 months in clinical areas. In total, 13 study participants assembled surgical trays in the central sterile supply department. While using the management system, trays were assembled 94 times. During this period, no assembly errors occurred. An instrument malfunction had occurred after the 19th, 56th, and 73 th uses, no malfunction caused by the RFID tags, and usage history had been recorded. Additionally, the time it took to assemble surgical trays was recorded, and the long-term usability of the management system was evaluated. The system could record the number of uses and the defective history of each surgical instrument. In addition, the history of the frequency of instruments being transferred from one tray to another was recorded. The results suggest that our system can be used to manage instruments safely. Additionally, the management system was acquired of the learning effect and the usability on daily maintenance. This finding suggests that the management system examined here ensures surgical instrument and tray assembly quality.

Mobile Applications for Diabetics: A Systematic Review and Expert-Based Usability Evaluation Considering the Special Requirements of Diabetes Patients Age 50 Years or Older

PubMed Central

Quade, Mandy; Kirch, Wilhelm

2014-01-01

Background A multitude of mhealth (mobile health) apps have been developed in recent years to support effective self-management of patients with diabetes mellitus type 1 or 2. Objective We carried out a systematic review of all currently available diabetes apps for the operating systems iOS and Android. We considered the number of newly released diabetes apps, range of functions, target user groups, languages, acquisition costs, user ratings, available interfaces, and the connection between acquisition costs and user ratings. Additionally, we examined whether the available applications serve the special needs of diabetes patients aged 50 or older by performing an expert-based usability evaluation. Methods We identified relevant keywords, comparative categories, and their specifications. Subsequently, we performed the app review based on the information given in the Google Play Store, the Apple App Store, and the apps themselves. In addition, we carried out an expert-based usability evaluation based on a representative 10% sample of diabetes apps. Results In total, we analyzed 656 apps finding that 355 (54.1%) offered just one function and 348 (53.0%) provided a documentation function. The dominating app language was English (85.4%, 560/656), patients represented the main user group (96.0%, 630/656), and the analysis of the costs revealed a trend toward free apps (53.7%, 352/656). The median price of paid apps was €1.90. The average user rating was 3.6 stars (maximum 5). Our analyses indicated no clear differences in the user rating between free and paid apps. Only 30 (4.6%) of the 656 available diabetes apps offered an interface to a measurement device. We evaluated 66 apps within the usability evaluation. On average, apps were rated best regarding the criterion “comprehensibility” (4.0 out of 5.0), while showing a lack of “fault tolerance” (2.8 out of 5.0). Of the 66 apps, 48 (72.7%) offered the ability to read the screen content aloud. The number of functions was significantly negative correlated with usability. The presence of documentation and analysis functions reduced the usability score significantly by 0.36 and 0.21 points. Conclusions A vast number of diabetes apps already exist, but the majority offer similar functionalities and combine only one to two functions in one app. Patients and physicians alike should be involved in the app development process to a greater extent. We expect that the data transmission of health parameters to physicians will gain more importance in future applications. The usability of diabetes apps for patients aged 50 or older was moderate to good. But this result applied mainly to apps offering a small range of functions. Multifunctional apps performed considerably worse in terms of usability. Moreover, the presence of a documentation or analysis function resulted in significantly lower usability scores. The operability of accessibility features for diabetes apps was quite limited, except for the feature “screen reader”. PMID:24718852

Wireless power transfer exploring spin rectification and inverse spin Hall effects

NASA Astrophysics Data System (ADS)

Seeger, R. L.; Garcia, W. J. S.; Dugato, D. A.; da Silva, R. B.; Harres, A.

2018-04-01

Devices based on spin rectification effects are of great interest for broadband communication applications, since they allow the rectification of radio frequency signals by simple ferromagnetic materials. The phenomenon is enhanced at ferromagnetic resonance condition, which may be attained when an external magnetic field is applied. The necessity of such field, however, hinders technological applications. Exploring spin rectification and spin Hall effects in exchange-biased samples, we were able to rectify radio frequency signals without an external applied magnetic field. Direct voltages of the order of μV were obtained when Ta/NiFe/FeMn/Ta thin films were exposed to microwaves in a shorted microstrip line for a relatively broad frequency range. Connecting the films to a resistive load, we estimated the fraction of the incident radio frequency power converted into usable dc power.

Design and optimization of a modal- independent linear ultrasonic motor.

PubMed

Zhou, Shengli; Yao, Zhiyuan

2014-03-01

To simplify the design of the linear ultrasonic motor (LUSM) and improve its output performance, a method of modal decoupling for LUSMs is proposed in this paper. The specific embodiment of this method is decoupling of the traditional LUSM stator's complex vibration into two simple vibrations, with each vibration implemented by one vibrator. Because the two vibrators are designed independently, their frequencies can be tuned independently and frequency consistency is easy to achieve. Thus, the method can simplify the design of the LUSM. Based on this method, a prototype modal- independent LUSM is designed and fabricated. The motor reaches its maximum thrust force of 47 N, maximum unloaded speed of 0.43 m/s, and maximum power of 7.85 W at applied voltage of 200 Vpp. The motor's structure is then optimized by controlling the difference between the two vibrators' resonance frequencies to reach larger output speed, thrust, and power. The optimized results show that when the frequency difference is 73 Hz, the output force, speed, and power reach their maximum values. At the input voltage of 200 Vpp, the motor reaches its maximum thrust force of 64.2 N, maximum unloaded speed of 0.76 m/s, maximum power of 17.4 W, maximum thrust-weight ratio of 23.7, and maximum efficiency of 39.6%.

Debunking Health IT Usability Myths

PubMed Central

Staggers, N.; Xiao, Y.; Chapman, L.

2013-01-01

Poor usability is a threat to patient safety and linked to productivity loss, workflow disruption, user frustration, sub-optimal product use and system de-installations. Although usability is receiving more attention nationally and internationally, myths about usability persist. This editorial debunks five common myths about usability (1) usability only concerns the look and feel of a product and is, therefore, only a minor concern, (2) usability is not measurable, (3) usability stifles innovation, (4) vendors are solely responsible for product usability, and (5) usability methods are not practical for use in healthcare. PMID:23874361

State of the (net)work address Developing criteria for applying social networking to the work environment.

PubMed

Valdez, André Calero; Schaar, Anne Kathrin; Ziefle, Martina

2012-01-01

In an increasingly faster paced innovative world, maintaining the ability to innovate in spite of an aging work force will become every company's strongest leverage for success. Tapping the latent knowledge resources and creativity of overlooked employees and persisting crucial information for business conduct are promising results for social networking sites (SNS) in a working context. Usability and usefulness are exponential factors in creating a successful SNS. In order to make a SNS usable for a heterogeneous user group, analyses of user diversity in regard to social media need to be done. Furthermore differences in communication medium and frequency in regard to age, content, hierarchy position, departmental thresholds and company size need to be analyzed. For analysis purposes both qualitative and quantitative research methods were applied. Strong effects of age and communication content were found in survey with 194 participants.

Frequency adjustable MEMS vibration energy harvester

NASA Astrophysics Data System (ADS)

Podder, P.; Constantinou, P.; Amann, A.; Roy, S.

2016-10-01

Ambient mechanical vibrations offer an attractive solution for powering the wireless sensor nodes of the emerging “Internet-of-Things”. However, the wide-ranging variability of the ambient vibration frequencies pose a significant challenge to the efficient transduction of vibration into usable electrical energy. This work reports the development of a MEMS electromagnetic vibration energy harvester where the resonance frequency of the oscillator can be adjusted or tuned to adapt to the ambient vibrational frequency. Micro-fabricated silicon spring and double layer planar micro-coils along with sintered NdFeB micro-magnets are used to construct the electromagnetic transduction mechanism. Furthermore, another NdFeB magnet is adjustably assembled to induce variable magnetic interaction with the transducing magnet, leading to significant change in the spring stiffness and resonance frequency. Finite element analysis and numerical simulations exhibit substantial frequency tuning range (25% of natural resonance frequency) by appropriate adjustment of the repulsive magnetic interaction between the tuning and transducing magnet pair. This demonstrated method of frequency adjustment or tuning have potential applications in other MEMS vibration energy harvesters and micromechanical oscillators.

Experimental Validation of Pulse Phase Tracking for X-Ray Pulsar Based

NASA Technical Reports Server (NTRS)

Anderson, Kevin

2012-01-01

Pulsars are a form of variable celestial source that have shown to be usable as aids for autonomous, deep space navigation. Particularly those sources emitting in the X-ray band are ideal for navigation due to smaller detector sizes. In this paper X-ray photons arriving from a pulsar are modeled as a non-homogeneous Poisson process. The method of pulse phase tracking is then investigated as a technique to measure the radial distance traveled by a spacecraft over an observation interval. A maximum-likelihood phase estimator (MLE) is used for the case where the observed frequency signal is constant. For the varying signal frequency case, an algorithm is used in which the observation window is broken up into smaller blocks over which an MLE is used. The outputs of this phase estimation process were then looped through a digital phase-locked loop (DPLL) in order to reduce the errors and produce estimates of the doppler frequency. These phase tracking algorithms were tested both in a computer simulation environment and using the NASA Goddard Space flight Center X-ray Navigation Laboratory Testbed (GXLT). This provided an experimental validation with photons being emitted by a modulated X-ray source and detected by a silicon-drift detector. Models of the Crab pulsar and the pulsar B1821-24 were used in order to generate test scenarios. Three different simulated detector trajectories were used to be tracked by the phase tracking algorithm: a stationary case, one with constant velocity, and one with constant acceleration. All three were performed in one-dimension along the line of sight to the pulsar. The first two had a constant signal frequency and the third had a time varying frequency. All of the constant frequency cases were processed using the MLE, and it was shown that they tracked the initial phase within 0.15% for the simulations and 2.5% in the experiments, based on an average of ten runs. The MLE-DPLL cascade version of the phase tracking algorithm was used in the varying frequency case. This resulted in tracking of the phase and frequency by the DPLL outputs in both the simulation and experimental environments. The crab pulsar was experimentally tested with a trajectory with a higher acceleration. In this case the phase error tended toward zero as the observation extended to 250 seconds and the doppler frequency error tended to zero in under 100 seconds.

Dye based photodiodes for solar energy applications

NASA Astrophysics Data System (ADS)

Mensah-Darkwa, K.; Ocaya, R.; Dere, A.; Al-Sehemi, Abdullah G.; Al-Ghamdi, Ahmed A.; Soylu, M.; Gupta, R. K.; Yakuphanoglu, F.

2017-10-01

Coumarin (CO) doped methylene blue (MB) organic photo-devices were fabricated. The CO-doped MB (0.00, 0.01, 0.03, 0.05, 0.1 wt% CO) were coated onto the surface of a p-type Si substrate by drop casting method. Some electrical parameters of the devices have been examined by current-voltage ( I- V), capacitance-voltage ( C- V), and conductance-voltage ( G- V) measurements. The fabricated devices had excellent rectifying properties. The diode exhibits a non-ideal diode behavior due to the series resistance and interface layer. The ideality factor, the barrier height, and the series resistance values of the diode as a function of doping and light illumination have been estimated using modified Cheung-Cheung and Norde's method. The highest I photo/ I dark photosensitivity of 5606 was observed for the diode having 0.01 CO doping at 100 mW/cm2 under -3 V. Furthermore, change of capacitance and conductance measurements with frequency is related to the existence of interface states. A maximum power conversion efficiency of 2.4% is estimated for the fabricated devices. The results reveal that coumarin-doped methylene blue/ p-Si heterojunction can be used as a photodiode in optoelectronic applications. It is also usable in low-power photovoltaic applications.

Characterization of depolarizing fringing fields of a liquid crystal spatial light modulator for laser beam steering

NASA Astrophysics Data System (ADS)

Haellstig, Emil J.; Martin, Torleif; Stigwall, Johan; Sjoqvist, Lars; Lindgren, Mikael

2004-02-01

A commercial linear one-dimensional, 1x4096 pixels, zero-twist nematic liquid crystal spatial light modulator (SLM), giving more than 2π phase modulation at λ = 850 nm, was evaluated for beam steering applications. The large ratio (7:1) between the liquid crystal layer thickness and pixel width gives rise to voltage leakage and fringing fields between pixels. Due to the fringing fields the ideal calculated phase patterns cannot be perfectly realized by the device. Losses in high frequency components in the phase patterns were found to limit the maximum deflection angle. The inhomogeneous optical anisotropy of the SLM was determined by modelling of the liquid crystal director distribution within the electrode-pixel structure. The effects of the fringing fields on the amplitude and phase modulation were studied by full vector finite-difference time-domain simulations. It was found that the fringing fields also resulted in coupling into an unwanted polarization mode. Measurements of how this mode coupling affects the beam steering quality were carried out and the results compared with calculated results. A method to compensate for the fringing field effects is discussed and it is shown how the usable steering range of the SLM can be extended to +/- 2 degrees.

Palliative Care Planner: A Pilot Study to Evaluate Acceptability and Usability of an Electronic Health Records System-integrated, Needs-targeted App Platform.

PubMed

Cox, Christopher E; Jones, Derek M; Reagan, Wen; Key, Mary D; Chow, Vinca; McFarlin, Jessica; Casarett, David; Creutzfeldt, Claire J; Docherty, Sharron L

2018-01-01

The quality and patient-centeredness of intensive care unit (ICU)-based palliative care delivery is highly variable. To develop and pilot an app platform for clinicians and ICU patients and their family members that enhances the delivery of needs-targeted palliative care. In the development phase of the study, we developed an electronic health record (EHR) system-integrated mobile web app system prototype, PCplanner (Palliative Care Planner). PCplanner screens the EHR for ICU patients meeting any of five prompts (triggers) for palliative care consultation, allows families to report their unmet palliative care needs, and alerts clinicians to these needs. The evaluation phase included a prospective before/after study conducted at a large academic medical center. Two control populations were enrolled in the before period to serve as context for the intervention. First, 25 ICU patients who received palliative care consults served as patient-level controls. Second, 49 family members of ICU patients who received mechanical ventilation for at least 48 hours served as family-level controls. Afterward, 14 patients, 18 family members, and 10 clinicians participated in the intervention evaluation period. Family member outcomes measured at baseline and 4 days later included acceptability (Client Satisfaction Questionnaire [CSQ]), usability (Systems Usability Scale [SUS]), and palliative care needs, assessed with the adapted needs of social nature, existential concerns, symptoms, and therapeutic interaction (NEST) scale; the Patient-Centeredness of Care Scale (PCCS); and the Perceived Stress Scale (PSS). Patient outcomes included frequency of goal concordant treatment, hospital length of stay, and discharge disposition. Family members reported high PCplanner acceptability (mean CSQ, 14.1 [SD, 1.4]) and usability (mean SUS, 21.1 [SD, 1.7]). PCplanner family member recipients experienced a 12.7-unit reduction in NEST score compared with a 3.4-unit increase among controls (P = 0.002), as well as improved mean scores on the PCCS (6.6 [SD, 5.8]) and the PSS (-0.8 [SD, 1.9]). The frequency of goal-concordant treatment increased over the course of the intervention (n = 14 [SD, 79%] vs. n = 18 [SD, 100%]). Compared with palliative care controls, intervention patients received palliative care consultation sooner (3.9 [SD, 2.7] vs. 6.9 [SD, 7.1] mean days), had a shorter mean hospital length of stay (20.5 [SD, 9.1] vs. 22.3 [SD, 16.0] patient number), and received hospice care more frequently (5 [36%] vs. 5 [20%]), although these differences were not statistically significant. PCplanner represents an acceptable, usable, and clinically promising systems-based approach to delivering EHR-triggered, needs-targeted ICU-based palliative care within a standard clinical workflow. A clinical trial in a larger population is needed to evaluate its efficacy.

Highly efficient frequency conversion with bandwidth compression of quantum light

PubMed Central

Allgaier, Markus; Ansari, Vahid; Sansoni, Linda; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Harder, Georg; Brecht, Benjamin; Silberhorn, Christine

2017-01-01

Hybrid quantum networks rely on efficient interfacing of dissimilar quantum nodes, as elements based on parametric downconversion sources, quantum dots, colour centres or atoms are fundamentally different in their frequencies and bandwidths. Although pulse manipulation has been demonstrated in very different systems, to date no interface exists that provides both an efficient bandwidth compression and a substantial frequency translation at the same time. Here we demonstrate an engineered sum-frequency-conversion process in lithium niobate that achieves both goals. We convert pure photons at telecom wavelengths to the visible range while compressing the bandwidth by a factor of 7.47 under preservation of non-classical photon-number statistics. We achieve internal conversion efficiencies of 61.5%, significantly outperforming spectral filtering for bandwidth compression. Our system thus makes the connection between previously incompatible quantum systems as a step towards usable quantum networks. PMID:28134242

Airflow energy harvesting with high wind velocities for industrial applications

NASA Astrophysics Data System (ADS)

Chew, Z. J.; Tuddenham, S. B.; Zhu, M.

2016-11-01

An airflow energy harvester capable of harvesting energy from vortices at high speed is presented in this paper. The airflow energy harvester is implemented using a modified helical Savonius turbine and an electromagnetic generator. A power management module with maximum power point finding capability is used to manage the harvested energy and convert the low voltage magnitude from the generator to a usable level for wireless sensors. The airflow energy harvester is characterized using vortex generated by air hitting a plate in a wind tunnel. By using an aircraft environment with wind speed of 17 m/s as case study, the output power of the airflow energy harvester is measured to be 126 mW. The overall efficiency of the power management module is 45.76 to 61.2%, with maximum power point tracking efficiency of 94.21 to 99.72% for wind speed of 10 to 18 m/s, and has a quiescent current of 790 nA for the maximum power point tracking circuit.

A knowledge translation intervention to enhance clinical application of a virtual reality system in stroke rehabilitation.

PubMed

Levac, Danielle; Glegg, Stephanie M N; Sveistrup, Heidi; Colquhoun, Heather; Miller, Patricia A; Finestone, Hillel; DePaul, Vincent; Harris, Jocelyn E; Velikonja, Diana

2016-10-06

Despite increasing evidence for the effectiveness of virtual reality (VR)-based therapy in stroke rehabilitation, few knowledge translation (KT) resources exist to support clinical integration. KT interventions addressing known barriers and facilitators to VR use are required. When environmental barriers to VR integration are less amenable to change, KT interventions can target modifiable barriers related to therapist knowledge and skills. A multi-faceted KT intervention was designed and implemented to support physical and occupational therapists in two stroke rehabilitation units in acquiring proficiency with use of the Interactive Exercise Rehabilitation System (IREX; GestureTek). The KT intervention consisted of interactive e-learning modules, hands-on workshops and experiential practice. Evaluation included the Assessing Determinants of Prospective Take Up of Virtual Reality (ADOPT-VR) Instrument and self-report confidence ratings of knowledge and skills pre- and post-study. Usability of the IREX was measured with the System Usability Scale (SUS). A focus group gathered therapist experiences. Frequency of IREX use was recorded for 6 months post-study. Eleven therapists delivered a total of 107 sessions of VR-based therapy to 34 clients with stroke. On the ADOPT-VR, significant pre-post improvements in therapist perceived behavioral control (p = 0.003), self-efficacy (p = 0.005) and facilitating conditions (p =0.019) related to VR use were observed. Therapist intention to use VR did not change. Knowledge and skills improved significantly following e-learning completion (p = 0.001) and was sustained 6 months post-study. Below average perceived usability of the IREX (19 th percentile) was reported. Lack of time was the most frequently reported barrier to VR use. A decrease in frequency of perceived barriers to VR use was not significant (p = 0.159). Two therapists used the IREX sparingly in the 6 months following the study. Therapists reported that client motivation to engage with VR facilitated IREX use in practice but that environmental and IREX-specific barriers limited use. Despite increased knowledge and skills in VR use, the KT intervention did not alter the number of perceived barriers to VR use, intention to use or actual use of VR. Poor perceived system usability had an impact on integration of this particular VR system into clinical practice.

Parametric study of transport beam lines for electron beams accelerated by laser-plasma interaction

NASA Astrophysics Data System (ADS)

Scisciò, M.; Lancia, L.; Migliorati, M.; Mostacci, A.; Palumbo, L.; Papaphilippou, Y.; Antici, P.

2016-03-01

In the last decade, laser-plasma acceleration of high-energy electrons has attracted strong attention in different fields. Electrons with maximum energies in the GeV range can be laser-accelerated within a few cm using multi-hundreds terawatt (TW) lasers, yielding to very high beam currents at the source (electron bunches with up to tens-hundreds of pC in a few fs). While initially the challenge was to increase the maximum achievable electron energy, today strong effort is put in the control and usability of these laser-generated beams that still lack of some features in order to be used for applications where currently conventional, radio-frequency (RF) based, electron beam lines represent the most common and efficient solution. Several improvements have been suggested for this purpose, some of them acting directly on the plasma source, some using beam shaping tools located downstream. Concerning the latter, several studies have suggested the use of conventional accelerator magnetic devices (such as quadrupoles and solenoids) as an easy implementable solution when the laser-plasma accelerated beam requires optimization. In this paper, we report on a parametric study related to the transport of electron beams accelerated by laser-plasma interaction, using conventional accelerator elements and tools. We focus on both, high energy electron beams in the GeV range, as produced on petawatt (PW) class laser systems, and on lower energy electron beams in the hundreds of MeV range, as nowadays routinely obtained on commercially available multi-hundred TW laser systems. For both scenarios, our study allows understanding what are the crucial parameters that enable laser-plasma accelerators to compete with conventional ones and allow for a beam transport. We show that suitable working points require a tradeoff-combination between low beam divergence and narrow energy spread.

A continuous usability evaluation of an electronic medication administration record application.

PubMed

Vicente Oliveros, Noelia; Gramage Caro, Teresa; Pérez Menéndez-Conde, Covadonga; Álvarez-Diaz, Ana María; Martín-Aragón Álvarez, Sagrario; Bermejo Vicedo, Teresa; Delgado Silveira, Eva

2017-12-01

The complexity of an electronic medication administration record (eMAR) has been underestimated by most designers in the past. Usability issues, such as poorly designed user application flow in eMAR, are therefore of vital importance, since they can have a negative impact on nursing activities and result in poor outcomes. The purpose of this study was to evaluate the usability of an eMAR application during its development. A usability evaluation was conducted during the development of the eMAR application. Two usability methods were used: a heuristic evaluation complemented by usability testing. Each eMAR application version provided by the vendor was evaluated by 2 hospital pharmacists, who applied the heuristic method. They reviewed the eMAR tasks, detected usability problems and their heuristic violations, and rated the severity of the usability problems. Usability testing was used to assess the final application version by observing how 3 nurses interacted with the application. Thirty-four versions were assessed before the eMAR application was considered usable. During the heuristic evaluation, the usability problems decreased from 46 unique usability problems in version 1 (V1) to 9 in version 34 (V34). In V1, usability problems were categorized into 154 heuristic violations, which decreased to 27 in V34. The average severity rating also decreased from major usability problem (2.96) to no problem (0.23). During usability testing, the 3 nurses did not encounter new usability problems. A thorough heuristic evaluation is a good method for obtaining a usable eMAR application. This evaluation points key areas for improvement and decreases usability problems and their severity. © 2017 John Wiley & Sons, Ltd.

From expert-derived user needs to user-perceived ease of use and usefulness: a two-phase mixed-methods evaluation framework.

PubMed

Boland, Mary Regina; Rusanov, Alexander; So, Yat; Lopez-Jimenez, Carlos; Busacca, Linda; Steinman, Richard C; Bakken, Suzanne; Bigger, J Thomas; Weng, Chunhua

2014-12-01

Underspecified user needs and frequent lack of a gold standard reference are typical barriers to technology evaluation. To address this problem, this paper presents a two-phase evaluation framework involving usability experts (phase 1) and end-users (phase 2). In phase 1, a cross-system functionality alignment between expert-derived user needs and system functions was performed to inform the choice of "the best available" comparison system to enable a cognitive walkthrough in phase 1 and a comparative effectiveness evaluation in phase 2. During phase 2, five quantitative and qualitative evaluation methods are mixed to assess usability: time-motion analysis, software log, questionnaires - System Usability Scale and the Unified Theory of Acceptance of Use of Technology, think-aloud protocols, and unstructured interviews. Each method contributes data for a unique measure (e.g., time motion analysis contributes task-completion-time; software log contributes action transition frequency). The measures are triangulated to yield complementary insights regarding user-perceived ease-of-use, functionality integration, anxiety during use, and workflow impact. To illustrate its use, we applied this framework in a formative evaluation of a software called Integrated Model for Patient Care and Clinical Trials (IMPACT). We conclude that this mixed-methods evaluation framework enables an integrated assessment of user needs satisfaction and user-perceived usefulness and usability of a novel design. This evaluation framework effectively bridges the gap between co-evolving user needs and technology designs during iterative prototyping and is particularly useful when it is difficult for users to articulate their needs for technology support due to the lack of a baseline. Copyright © 2013 Elsevier Inc. All rights reserved.

Magnetic refrigeration using flux compression in superconductors

NASA Technical Reports Server (NTRS)

Israelsson, U. E.; Strayer, D. M.; Jackson, H. W.; Petrac, D.

1990-01-01

The feasibility of using flux compression in high-temperature superconductors to produce the large time-varying magnetic fields required in a field cycled magnetic refrigerator operating between 20 K and 4 K is presently investigated. This paper describes the refrigerator concept and lists limitations and advantages in comparison with conventional refrigeration techniques. The maximum fields obtainable by flux compression in high-temperature supercoductor materials, as presently prepared, are too low to serve in such a refrigerator. However, reports exist of critical current values that are near usable levels for flux pumps in refrigerator applications.

4-haloethenylphenyl tropane:serotonin transporter imaging agents

DOEpatents

Goodman, Mark M.; Martarello, Laurent

2005-01-18

A series of compounds in the 4-fluoroalkyl-3-halophenyl nortropanes and 4-haloethenylphenyl tropane families are described as diagnostic and therapeutic agents for diseases associated with serotonin transporter dysfunction. These compounds bind to serotonin transporter protein with high affinity and selectivity. The invention provides methods of synthesis which incorporate radioisotopic halogens at a last step which permit high radiochemical yield and maximum usable product life. The radiolabeled compounds of the invention are useful as imaging agents for visualizing the location and density of serotonin transporter by PET and SPECT imaging.

Electric Drive Study. Volume 1

DTIC Science & Technology

1987-12-21

CONDITIONER HIGH VOLTAGE DC ICONDITIONER 3 ,300-50 VOLT5), dCONTROL! Figure 5-4. Typical AC Drive System 20 system usable with an induction motor. The...controlling component in an AC drive is the motor power conditioner . This component changes the high voltage DC power to controlled AC power of...selected voltage and frequency which is applied to the drive motors. Since the vehicle gains stored energy as it is accelerated, the motor power conditioner

Soldier-Robot Team Communication: An Investigation of Exogenous Orienting Visual Display Cues and Robot Reporting Preferences

DTIC Science & Technology

2018-02-12

usability preference. Results under the second focus showed that the frequency with which participants expected status updates differed depending upon the...assistance requests for both navigational route and building selection depending on the type of exogenous visual cues displayed? 3) Is there a difference...in response time to visual reports for both navigational route and building selection depending on the type of exogenous visual cues displayed? 4

Microwave characteristics of GaAs MMIC integratable optical detectors

NASA Technical Reports Server (NTRS)

Claspy, Paul C.; Hill, Scott M.; Bhasin, Kul B.

1989-01-01

Interdigitated photoconductive detectors were fabricated on microwave device structures, making them easily integratable with Monolithic Microwave Integrated Circuits (MMIC). Detector responsivity as high as 2.5 A/W and an external quantum efficiency of 3.81 were measured. Response speed was nearly independent of electrode geometry, and all detectors had usable response at frequencies to 6 GHz. A small signal model of the detectors based on microwave measurements was also developed.

Interactivity Centered Usability Evaluation (ICUE) for Course Management Systems

ERIC Educational Resources Information Center

Yoon, Sangil

2010-01-01

ICUE (Interactivity Centered Usability Evaluation) is an enhanced usability testing protocol created by the researcher. ICUE augments the facilitator's role for usability testing, and offers strategies in developing and presenting usability tasks during a testing session. ICUE was designed to address weaknesses found in the usability evaluation of…

Usability Prediction & Ranking of SDLC Models Using Fuzzy Hierarchical Usability Model

NASA Astrophysics Data System (ADS)

Gupta, Deepak; Ahlawat, Anil K.; Sagar, Kalpna

2017-06-01

Evaluation of software quality is an important aspect for controlling and managing the software. By such evaluation, improvements in software process can be made. The software quality is significantly dependent on software usability. Many researchers have proposed numbers of usability models. Each model considers a set of usability factors but do not cover all the usability aspects. Practical implementation of these models is still missing, as there is a lack of precise definition of usability. Also, it is very difficult to integrate these models into current software engineering practices. In order to overcome these challenges, this paper aims to define the term `usability' using the proposed hierarchical usability model with its detailed taxonomy. The taxonomy considers generic evaluation criteria for identifying the quality components, which brings together factors, attributes and characteristics defined in various HCI and software models. For the first time, the usability model is also implemented to predict more accurate usability values. The proposed system is named as fuzzy hierarchical usability model that can be easily integrated into the current software engineering practices. In order to validate the work, a dataset of six software development life cycle models is created and employed. These models are ranked according to their predicted usability values. This research also focuses on the detailed comparison of proposed model with the existing usability models.

Effect of Training Frequency on Maximum Expiratory Pressure

ERIC Educational Resources Information Center

Anand, Supraja; El-Bashiti, Nour; Sapienza, Christine

2012-01-01

Purpose: To determine the effects of expiratory muscle strength training (EMST) frequency on maximum expiratory pressure (MEP). Method: We assigned 12 healthy participants to 2 groups of training frequency (3 days per week and 5 days per week). They completed a 4-week training program on an EMST trainer (Aspire Products, LLC). MEP was the primary…

4-GHz counters bring synthesizers up to speed

NASA Astrophysics Data System (ADS)

Lee, F.; Miller, R.

1984-06-01

The availability of digital IC counters built on GaAs makes direct frequency division in microwave synthesizers possible. Four GHz is the highest clock rate achievable in production designs. These devices have the ability to drive TTL/CMOS logic, and the counter can be connected directly to single-chip frequency synthesizers controllers. A complete microwave sythesizer is formed by two chips and a voltage-controlled oscillator (VCO). The advantages of GaAs are discussed along with flip-flop basics, aspects of device fabrication, and the characteristics of GaAs MESAFETs. Attention is given to a GaAs prescaler usable for direct conversion, four kinds of flip-flops in a divide-by-two mode, and seven-stage binary ripple counters.

Towards a Usability and Error "Safety Net": A Multi-Phased Multi-Method Approach to Ensuring System Usability and Safety.

PubMed

Kushniruk, Andre; Senathirajah, Yalini; Borycki, Elizabeth

2017-01-01

The usability and safety of health information systems have become major issues in the design and implementation of useful healthcare IT. In this paper we describe a multi-phased multi-method approach to integrating usability engineering methods into system testing to ensure both usability and safety of healthcare IT upon widespread deployment. The approach involves usability testing followed by clinical simulation (conducted in-situ) and "near-live" recording of user interactions with systems. At key stages in this process, usability problems are identified and rectified forming a usability and technology-induced error "safety net" that catches different types of usability and safety problems prior to releasing systems widely in healthcare settings.

From Usability Engineering to Evidence-based Usability in Health IT.

PubMed

Marcilly, Romaric; Peute, Linda; Beuscart-Zephir, Marie-Catherine

2016-01-01

Usability is a critical factor in the acceptance, safe use, and success of health IT. The User-Centred Design process is widely promoted to improve usability. However, this traditional case by case approach that is rooted in the sound understanding of users' needs is not sufficient to improve technologies' usability and prevent usability-induced use-errors that may harm patients. It should be enriched with empirical evidence. This evidence is on design elements (what are the most valuable design principles, and the worst usability mistakes), and on the usability evaluation methods (which combination of methods is most suitable in which context). To achieve this evidence, several steps must be fulfilled and challenges must be overcome. Some attempts to search evidence for designing elements of health IT and for usability evaluation methods exist and are summarized. A concrete instance of evidence-based usability design principles for medication-related alerting systems is briefly described.

Technology for home dementia care: A prototype locating system put to the test.

PubMed

Megges, Herlind; Freiesleben, Silka Dawn; Jankowski, Natalie; Haas, Brigitte; Peters, Oliver

2017-09-01

The user experience of persons with dementia and their primary caregivers with locating systems is not firmly established. Eighteen dyads used a prototype locating system during 4 weeks. Primary outcome measures were ratings of usability, and product functions and features. Secondary outcome measures were caregiver burden, perceived self-efficacy, frequency of use, and willingness to purchase the prototype. Changes in scores between baseline (T 1 ) and end of testing period (T 2 ) were compared by performing independent and dependent samples correlations and descriptive statistics. Seventeen dyads made up the final sample. Ratings of usability and product functions and features were fair, but usability ratings were significantly reduced after 4 weeks. Although the prototype was used infrequently by majority of the participants, most caregivers would be willing to purchase the prototype, with men more willing than women. No significant change in technological willingness, caregiver burden, or perceived self-efficacy was found between T 1 and T 2 . Perceived self-efficacy significantly negatively correlated with willingness to purchase the prototype after 4 weeks. Results highlight the importance of including end users in the research and development phase of locating systems to improve the user experience in home dementia care. Necessary indications for further research are carrying out randomized controlled trials with larger, more representative samples and developing innovative software and hardware solutions.

Testing Quick Response (QR) Codes as an Innovation to Improve Feedback Among Geographically-Separated Clerkship Sites.

PubMed

Snyder, Matthew J; Nguyen, Dana R; Womack, Jasmyne J; Bunt, Christopher W; Westerfield, Katie L; Bell, Adriane E; Ledford, Christy J W

2018-03-01

Collection of feedback regarding medical student clinical experiences for formative or summative purposes remains a challenge across clinical settings. The purpose of this study was to determine whether the use of a quick response (QR) code-linked online feedback form improves the frequency and efficiency of rater feedback. In 2016, we compared paper-based feedback forms, an online feedback form, and a QR code-linked online feedback form at 15 family medicine clerkship sites across the United States. Outcome measures included usability, number of feedback submissions per student, number of unique raters providing feedback, and timeliness of feedback provided to the clerkship director. The feedback method was significantly associated with usability, with QR code scoring the highest, and paper second. Accessing feedback via QR code was associated with the shortest time to prepare feedback. Across four rotations, separate repeated measures analyses of variance showed no effect of feedback system on the number of submissions per student or the number of unique raters. The results of this study demonstrate that preceptors in the family medicine clerkship rate QR code-linked feedback as a high usability platform. Additionally, this platform resulted in faster form completion than paper or online forms. An overarching finding of this study is that feedback forms must be portable and easily accessible. Potential implementation barriers and the social norm for providing feedback in this manner need to be considered.

Perceptions of Smartphone User-Centered Mobile Health Tracking Apps Across Various Chronic Illness Populations: An Integrative Review.

PubMed

Birkhoff, Susan D; Smeltzer, Suzanne C

2017-07-01

This integrative review presents a synthesis of the current qualitative research addressing the motivating factors, usability, and experiences of mobile health tracking applications (apps) across various chronic disease populations. Integrative review of the literature. Databases used to conduct this integrative review included: PubMed Plus, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Google Scholar, Science Direct, and EBSCO megafile. The following search terms were used in all five databases: smartphone apps, apps, mHealth, eHealth, mobile health apps, health tracking apps, user-centered apps, wireless technology, engagement, qualitative, and usability. The initial literature review yielded 689 results. Once inclusion and exclusion criteria were employed, 11 studies met the criteria set forth for this review. The reviewed studies provided insight into users' perceptions, experiences, and motivations to incorporate smartphone mobile health apps into their daily lives when living with chronic illnesses. This review indicates the growing interest in user-centered mobile health tracking apps, but with little understanding of motivating factors that foster sustained app use. Mobile health tracking apps targeted to users with chronic conditions need to have a high level of usability in order to motivate users to sustain engagement with their mobile health tracking app. User-centered mobile health tracking app technology is being used with increasing frequency to potentially provide individualized support to chronic illness populations. © 2017 Sigma Theta Tau International.

[Benefits and usability of a pharmaceutical record in medical practice. A survey of hospital doctors and pharmacists (MATRIX study)].

PubMed

Schuers, M; Timsit, M; Gillibert, A; Fred, A; Griffon, N; Bénichou, J; Darmoni, S J; Staccini, P

2016-09-01

To evaluate the impact of the pharmaceutical patient record use in emergency, geriatric and anaesthesia and intensive care departments, an experimentation was launched in 2013 in 55 hospitals. The purpose of the study was to assess the opinions of physicians and pharmacists about the benefits and usability of the patient pharmaceutical record. An e-mailed self-administered questionnaire was sent to all the pharmacists, anaesthesiologists, geriatricians and emergency physicians of the 55 hospitals involved in the patient pharmaceutical record experimentation. The questionnaire assessed the usability of the patient pharmaceutical record using the "System Usability Scale", as well as its use, its benefits and limitations perceived in clinical practice, and overall user satisfaction. Questionnaires were collected from November 2014 to January 2015. Ninety-six questionnaires were collected, from 47 hospitals, representing 86% of the hospitals involved in the experimentation. The patient pharmaceutical record was effectively operational in 36 hospitals. Data from 73 questionnaires filled by physicians and pharmacists with potential experience with the patient pharmaceutical record were used for evaluation. Forty-two respondents were pharmacists (57%) and 31 were physicians (43%), including 13 geriatricians, 11 emergency physicians and 7 anaesthesiologists. Patient pharmaceutical record overall usability score was 62.5 out of 100. It did not vary with the profession or seniority of the respondent. It was positively correlated with the frequency of use. More than half of respondents reported that they never or uncommonly used the patient pharmaceutical record. The length of access to data period was considered as insufficient. Main obstacles to more utilization of the patient pharmaceutical record were the lack of information about the dosage of dispensed drugs, the low number of patients in possession of their health card and the low number of patients with an activated patient pharmaceutical record. Two years after the beginning of the experiment aiming to broaden the access to the patient pharmaceutical record to physicians, these first evaluation results are encouraging. The evaluation of the consequences of the access to the patient pharmaceutical record for physicians remains necessary. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Measuring AT Usability with the Modified System Usability Scale (SUS).

PubMed

Friesen, Emma L

2017-01-01

The modified System Usability Scale (SUS) is a widely used generic measure of product usability. This study concerns the usability of mobile shower commodes using correlations between the SUS and AT device-specific measures. Results suggest the modified SUS, and corresponding adjective-anchored rating scale, are appropriate for measuring MSC usability, and have potential for use with other AT devices.

Noise-based body-wave seismic tomography in an active underground mine.

NASA Astrophysics Data System (ADS)

Olivier, G.; Brenguier, F.; Campillo, M.; Lynch, R.; Roux, P.

2014-12-01

Over the last decade, ambient noise tomography has become increasingly popular to image the earth's upper crust. The seismic noise recorded in the earth's crust is dominated by surface waves emanating from the interaction of the ocean with the solid earth. These surface waves are low frequency in nature ( < 1 Hz) and not usable for imaging smaller structures associated with mining or oil and gas applications. The seismic noise recorded at higher frequencies are typically from anthropogenic sources, which are short lived, spatially unstable and not well suited for constructing seismic Green's functions between sensors with conventional cross-correlation methods. To examine the use of ambient noise tomography for smaller scale applications, continuous data were recorded for 5 months in an active underground mine in Sweden located more than 1km below surface with 18 high frequency seismic sensors. A wide variety of broadband (10 - 3000 Hz) seismic noise sources are present in an active underground mine ranging from drilling, scraping, trucks, ore crushers and ventilation fans. Some of these sources generate favorable seismic noise, while others are peaked in frequency and not usable. In this presentation, I will show that the noise generated by mining activity can be useful if periods of seismic noise are carefully selected. Although noise sources are not temporally stable and not evenly distributed around the sensor array, good estimates of the seismic Green's functions between sensors can be retrieved for a broad frequency range (20 - 400 Hz) when a selective stacking scheme is used. For frequencies below 100 Hz, the reconstructed Green's functions show clear body-wave arrivals for almost all of the 153 sensor pairs. The arrival times of these body-waves are picked and used to image the local velocity structure. The resulting 3-dimensional image shows a high velocity structure that overlaps with a known ore-body. The material properties of the ore-body differ from the host rock and is likely the cause of the observed high velocity structure. For frequencies above 200 Hz, the seismic waves are multiply scattered by the tunnels and excavations and used to determine the scattering properties of the medium. The results of this study should be useful for future imaging and exploration projects in mining and oil and gas industries.

LEOS 1992 - Summer Topical Meeting Digest Held in Santa Barbara, California on July 29-12 August, 1992

DTIC Science & Technology

1992-01-01

careful design of the device to maximise the relaxation oscillation resonance frequency [2], minimize leakage currents [2,3], and optimize other...and determines the maximum frequency of operation. With hybrid circuit construction this maximum frequency would generally be in the order of a few...operating at a frequency of 335.48 MHz. The resultant timing jitter is determined by sending both pulse trains into a rotating mirror optical

Barriers to comparing the usability of electronic health records.

PubMed

Ratwani, Raj M; Hettinger, A Zachary; Fairbanks, Rollin J

2017-04-01

Despite the widespread adoption of electronic health records (EHRs), usability of many EHRs continues to be suboptimal, with some vendors failing to meet usability standards, resulting in clinician frustration and patient safety hazards. In an effort to increase EHR vendor competition on usability, recommendations have been made and legislation drafted to develop comparison tools that would allow purchasers to better understand the usability of EHR products prior to purchase. Usability comparison can be based on EHR vendor design and development processes, vendor usability testing as part of the Office of the National Coordinator for Health Information Technology certification program, and usability of implemented products. Barriers exist within the current certified health technology program that prevent effective comparison of usability during each of these stages. We describe the importance of providing purchasers with improved information about EHR usability, barriers to making usability comparisons, and solutions to overcome these barriers. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Polycrystalline diamond RF MOSFET with MoO3 gate dielectric

NASA Astrophysics Data System (ADS)

Ren, Zeyang; Zhang, Jinfeng; Zhang, Jincheng; Zhang, Chunfu; Chen, Dazheng; Quan, Rudai; Yang, Jiayin; Lin, Zhiyu; Hao, Yue

2017-12-01

We report the radio frequency characteristics of the diamond metal-oxide-semiconductor field effect transistor with MoO3 gate dielectric for the first time. The device with 2-μm gate length was fabricated on high quality polycrystalline diamond. The maximum drain current of 150 mA/mm at VGS = -5 V and the maximum transconductance of 27 mS/mm were achieved. The extrinsic cutoff frequency of 1.2 GHz and the maximum oscillation frequency of 1.9 GHz have been measured. The moderate frequency characteristics are attributed to the moderate transconductance limited by the series resistance along the channel. We expect that the frequency characteristics of the device can be improved by increasing the magnitude of gm, or fundamentally decreasing the gate-controlled channel resistance and series resistance along the channel, and down-scaling the gate length.

Effect of current on the maximum possible reward.

PubMed

Gallistel, C R; Leon, M; Waraczynski, M; Hanau, M S

1991-12-01

Using a 2-lever choice paradigm with concurrent variable interval schedules of reward, it was found that when pulse frequency is increased, the preference-determining rewarding effect of 0.5-s trains of brief cathodal pulses delivered to the medial forebrain bundle of the rat saturates (stops increasing) at values ranging from 200 to 631 pulses/s (pps). Raising the current lowered the saturation frequency, which confirms earlier, more extensive findings showing that the rewarding effect of short trains saturates at pulse frequencies that vary from less than 100 pps to more than 800 pps, depending on the current. It was also found that the maximum possible reward--the magnitude of the reward at or beyond the saturation pulse frequency--increases with increasing current. Thus, increasing the current reduces the saturation frequency but increases the subjective magnitude of the maximum possible reward.

36 CFR 1193.39 - Prohibited reduction of accessibility, usability, and compatibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... accessibility, usability, and compatibility. 1193.39 Section 1193.39 Parks, Forests, and Public Property... Requirements for Accessibility and Usability § 1193.39 Prohibited reduction of accessibility, usability, and... accessibility, usability, or compatibility of telecommunications equipment or customer premises equipment. (b...

36 CFR 1193.39 - Prohibited reduction of accessibility, usability, and compatibility.

Code of Federal Regulations, 2011 CFR

2011-07-01

... accessibility, usability, and compatibility. 1193.39 Section 1193.39 Parks, Forests, and Public Property... Requirements for Accessibility and Usability § 1193.39 Prohibited reduction of accessibility, usability, and... accessibility, usability, or compatibility of telecommunications equipment or customer premises equipment. (b...

36 CFR 1193.39 - Prohibited reduction of accessibility, usability, and compatibility.

Code of Federal Regulations, 2014 CFR

2014-07-01

... accessibility, usability, and compatibility. 1193.39 Section 1193.39 Parks, Forests, and Public Property... Requirements for Accessibility and Usability § 1193.39 Prohibited reduction of accessibility, usability, and... accessibility, usability, or compatibility of telecommunications equipment or customer premises equipment. (b...

36 CFR 1193.39 - Prohibited reduction of accessibility, usability, and compatibility.

Code of Federal Regulations, 2012 CFR

2012-07-01

... accessibility, usability, and compatibility. 1193.39 Section 1193.39 Parks, Forests, and Public Property... Requirements for Accessibility and Usability § 1193.39 Prohibited reduction of accessibility, usability, and... accessibility, usability, or compatibility of telecommunications equipment or customer premises equipment. (b...

Usability of patient-centered health IT: mixed-methods usability study of ePill.

PubMed

Schmidt-Kraepelin, Manuel; Dehling, Tobias; Sunyaev, Ali

2014-01-01

To facilitate use of patient-centered health IT applications in everyday life, a high degree of usability is required. Based on the example of a patient-centered web application, we propose a usability study design enabling developers and researchers to assess usability of patient-centered health IT applications and derive implications for their improvement. Our study design integrates tasks that subjects have to process, an associated questionnaire based on Perceived Ease of Use, Perceived Usefulness, Attitude Toward Using, and Behavioral Intention to Use, a System Usability Scale questionnaire, and focus groups. Application of the usability study design demonstrates its feasibility and provides insights for assessment of usability in related projects in research and practice.

A Survey of Usability Practices in Free/Libre/Open Source Software

NASA Astrophysics Data System (ADS)

Paul, Celeste Lyn

A review of case studies about usability in eight Free/Libre/Open Source Software (FLOSS) projects showed that an important issue regarding a usability initiative in the project was the lack of user research. User research is a key component in the user-centered design (UCD) process and a necessary step for creating usable products. Reasons why FLOSS projects suffered from a lack of user research included poor or unclear project leadership, cultural differences between developer and designers, and a lack of usability engineers. By identifying these critical issues, the FLOSS usability community can begin addressing problems in the efficacy of usability activities and work towards creating more usable FLOSS products.

Post-deployment usability evaluation of a radiology workstation.

PubMed

Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi A; Oudkerk, Matthijs; Van Ooijen, Peter M A

2016-01-01

To determine the number, nature and severity of usability issues radiologists encounter while using a commercially available radiology workstation in clinical practice, and to assess how well the results of a pre-deployment usability evaluation of this workstation generalize to clinical practice. The usability evaluation consisted of semi-structured interviews and observations of twelve users using the workstation during their daily work. Usability issues and positive usability findings were documented. Each issue was given a severity rating and its root cause was determined. Results were compared to the results of a pre-deployment usability evaluation of the same workstation. Ninety-two usability issues were identified, ranging from issues that cause minor frustration or delay, to issues that cause significant delays, prevent users from completing tasks, or even pose a potential threat to patient safety. The results of the pre-deployment usability evaluation had limited generalizability to clinical practice. This study showed that radiologists encountered a large number and a wide variety of usability issues when using a commercially available radiology workstation in clinical practice. This underlines the need for effective usability engineering in radiology. Given the limitations of pre-deployment usability evaluation in radiology, which were confirmed by our finding that the results of a pre-deployment usability evaluation of this workstation had limited generalizability to clinical practice, it is vital that radiology workstation vendors devote significant resources to usability engineering efforts before deployment of their workstation, and to continue these efforts after the workstation is deployed in a hospital. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

How Do We Teach Usability? An Investigation of Usability Instruction in Technical Communication

ERIC Educational Resources Information Center

Chong, Felicia

2013-01-01

This dissertation investigates the curricular implementation of usability instruction in technical communication. Though there are a plethora of publications and studies on usability in technical communication, little discussion focuses on usability instruction in the classroom or its implementation in the curriculum. Thus, this exploratory…

Early-Stage Software Design for Usability

ERIC Educational Resources Information Center

Golden, Elspeth

2010-01-01

In spite of the goodwill and best efforts of software engineers and usability professionals, systems continue to be built and released with glaring usability flaws that are costly and difficult to fix after the system has been built. Although user interface (UI) designers, be they usability or design experts, communicate usability requirements to…

36 CFR § 1193.39 - Prohibited reduction of accessibility, usability, and compatibility.

Code of Federal Regulations, 2013 CFR

2013-07-01

... accessibility, usability, and compatibility. § 1193.39 Section § 1193.39 Parks, Forests, and Public Property... Requirements for Accessibility and Usability § 1193.39 Prohibited reduction of accessibility, usability, and... accessibility, usability, or compatibility of telecommunications equipment or customer premises equipment. (b...

Increasing EHR system usability through standards: Conformance criteria in the HL7 EHR-system functional model.

PubMed

Meehan, Rebecca A; Mon, Donald T; Kelly, Kandace M; Rocca, Mitra; Dickinson, Gary; Ritter, John; Johnson, Constance M

2016-10-01

Though substantial work has been done on the usability of health information technology, improvements in electronic health record system (EHR) usability have been slow, creating frustration, distrust of EHRs and the use of potentially unsafe work-arounds. Usability standards could be part of the solution for improving EHR usability. EHR system functional requirements and standards have been used successfully in the past to specify system behavior, the criteria of which have been gradually implemented in EHR systems through certification programs and other national health IT strategies. Similarly, functional requirements and standards for usability can help address the multitude of sequelae associated with poor usability. This paper describes the evidence-based functional requirements for usability contained in the Health Level Seven (HL7) EHR System Functional Model, and the benefits of open and voluntary EHR system usability standards. Copyright © 2016 Elsevier Inc. All rights reserved.

Usability in Mobile Electronic Data Collection Tools: Form Developers' Views.

PubMed

Mugisha, Alice; Babic, Ankica; Wakholi, Peter; Nankabirwa, Victoria; Tylleskar, Thorkild

2017-01-01

Mobile Electronic Data Collection Tools (MEDCTs) are created by form developers to collect data. Usability being one of the top quality attributes is of great concern to developers of any interactive applications. However, little is known about the form developers' understanding of usability, how they measure usability and their limitations in designing for usability. We conducted an empirical study where we aimed at getting the developers' views on usability by interviewing 8 form developers. These are creators of forms used for data collection. We found that developers knew about usability, but it was not their main focus during form development. Challenges included constraining deadlines, software limitations and the insufficient communication with the field users to establish the usability needs. Furthermore, the methods used to evaluate the usability of created forms varied amongst developers and these included in-house evaluations and feedback from piloting sessions with end users.

Asteroid models from photometry and complementary data sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaasalainen, Mikko

I discuss inversion methods for asteroid shape and spin reconstruction with photometry (lightcurves) and complementary data sources such as adaptive optics or other images, occultation timings, interferometry, and range-Doppler radar data. These are essentially different sampling modes (generalized projections) of plane-of-sky images. An important concept in this approach is the optimal weighting of the various data modes. The maximum compatibility estimate, a multi-modal generalization of the maximum likelihood estimate, can be used for this purpose. I discuss the fundamental properties of lightcurve inversion by examining the two-dimensional case that, though not usable in our three-dimensional world, is simple to analyze,more » and it shares essentially the same uniqueness and stability properties as the 3-D case. After this, I review the main aspects of 3-D shape representations, lightcurve inversion, and the inclusion of complementary data.« less

Microwave non-contact imaging of subcutaneous human body tissues.

PubMed

Kletsov, Andrey; Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

2015-10-01

A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated.

Geosynchronous platform definition study. Volume 3: Geosynchronous mission characteristics

NASA Technical Reports Server (NTRS)

1973-01-01

The objectives of the study were to examine the nature of currently planned and new evolutionary geosynchronous programs, to analyze alternative ways of conducting missions, to establish concepts for new systems to support geosynchronous programs in an effective and economical manner, and to define the logistic support to carry out these programs. In order to meet these objectives, it was necessary to define and examine general geosynchronous mission characteristics and the potentially applicable electromagnetic spectrum characteristics. An organized compilation of these data is given with emphasis on the development and use of the data. Fundamental geosynchronous orbit time histories, mission profile characteristics, and delivery system characteristics are presented. In addition, electromagnetic spectrum utilization is discussed in terms of the usable frequency spectrum, the spectrum potentially available considering established frequency allocations, and the technology status as it affects the ability to operate within specific frequency bands.

Evaluation of expert system application based on usability aspects

NASA Astrophysics Data System (ADS)

Munaiseche, C. P. C.; Liando, O. E. S.

2016-04-01

Usability usually defined as a point of human acceptance to a product or a system based on understands and right reaction to an interface. The performance of web application has been influence by the quality of the interface of that web to supporting information transfer process. Preferably, before the applications of expert systems were installed in the operational environment, these applications must be evaluated first by usability testing. This research aimed to measure the usability of the expert system application using tasks as interaction media. This study uses an expert system application to diagnose skin disease in human using questionnaire method which utilize the tasks as interaction media in measuring the usability. Certain tasks were executed by the participants in observing usability value of the application. The usability aspects observed were learnability, efficiency, memorability, errors, and satisfaction. Each questionnaire question represent aspects of usability. The results present the usability value for each aspect and the total average merit for all the five-usability aspect was 4.28, this indicated that the tested expert system application is in the range excellent for the usability level, so the application can be implemented as the operated system by user. The main contribution of the study is the research became the first step in using task model in the usability evaluation for the expert system application software.

Modeling of Army Research Laboratory EMP simulators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miletta, J.R.; Chase, R.J.; Luu, B.B.

1993-12-01

Models are required that permit the estimation of emitted field signatures from EMP simulators to design the simulator antenna structure, to establish the usable test volumes, and to estimate human exposure risk. This paper presents the capabilities and limitations of a variety of EMP simulator models useful to the Army's EMP survivability programs. Comparisons among frequency and time-domain models are provided for two powerful US Army Research Laboratory EMP simulators: AESOP (Army EMP Simulator Operations) and VEMPS II (Vertical EMP Simulator II).

Enhancing Access to Patient Education Information: A Pilot Usability Study

PubMed Central

Beaudoin, Denise E.; Rocha, Roberto A.; Tse, Tony

2005-01-01

Health care organizations are developing Web-based portals to provide patient access to personal health information and enhance patient-provider communication. This pilot study investigates two navigation models (“serial” and “menu-driven”) for improving access to education materials available through a portal. There was a trend toward greater user satisfaction with the menu-driven model. Model preference was influenced by frequency of Web use. Results should aid in the improvement of existing portals and in the development of new ones. PMID:16779179

Cuttlefish Sepia officinalis Preferentially Respond to Bottom Rather than Side Stimuli When Not Allowed Adjacent to Tank Walls

DTIC Science & Technology

2015-10-14

especially because cuttlefish are colorblind. Another possible concern is the flicker frequency of the plasma screens. The plasma screens used in... flicker . Given these reasons, we believe that the most reliable behavior with the least amount of human disturbance resulted from our use of the...0138690 October 14, 2015 15 / 18 Image analysis To mitigate the likelihood of autocorrelation, we used the two usable (i.e., non-blurry) images that were

Method of Lines Transpose an Implicit Vlasov Maxwell Solver for Plasmas

DTIC Science & Technology

2015-04-17

boundary crossings should be rare. Numerical results for the Bennett pinch are given in Figure 9. In order to resolve large gradients near the center of the...contributing to the large error at the center of the beam due to large gradients there) and with the finite beam cut-off radius and the outflow boundary...usable time step size can be limited by the numerical accuracy of the method when there are large gradients (high-frequency content) in the solution. We

Perceived Usability Evaluation of Learning Management Systems: Empirical Evaluation of the System Usability Scale

ERIC Educational Resources Information Center

Orfanou, Konstantina; Tselios, Nikolaos; Katsanos, Christos

2015-01-01

Perceived usability affects greatly student's learning effectiveness and overall learning experience, and thus is an important requirement of educational software. The System Usability Scale (SUS) is a well-researched and widely used questionnaire for perceived usability evaluation. However, surprisingly few studies have used SUS to evaluate the…

Study of a wireless power transmission system for an active capsule endoscope.

PubMed

Xin, Wenhui; Yan, Guozheng; Wang, Wenxin

2010-03-01

An active capsule endoscope (ACE) will consume much more energy than can be power by batteries. Its orientation and position are always undetermined when it continues the natural way down the gastrointestinal track. In order to deliver stable and sufficient energy to ACE safely, a wireless power transmission system based on inductive coupling is presented. The system consists of a Helmholtz primary coil outside and a multiple secondary coils inside the body. The Helmholtz primary coil is driven to generate a uniform alternating magnetic field covering the whole of the alimentary tract, and the multiple secondary coils receive energy regardless of the ACE's position and orientation relative to the generated magnetic field. The human tissue safety of the electromagnetic field generated by transmitting coil was evaluated, based on a high-resolution realistic human model. At least 310 mW usable power can be transmitted under the worst geometrical conditions. Outer dimensions of the power receiver, 10 mm diameter x 12 mm; transmitting power, 25 W; resonant frequency, 400 kHz. The maximum specific absorption rate (SAR) and current density of human tissues are 0.329 W/kg and 3.82 A/m(2), respectively, under the basic restrictions of the International Commission on Non-ionizing Radiation Protection (ICNIRP). The designed wireless power transmission is shown to be feasible and potentially safe in a future application. (c) 2010 John Wiley & Sons, Ltd.

Cryogenic Amplifier Based Receivers at Submillimeter Wavelengths

NASA Technical Reports Server (NTRS)

Chattopadhyay, Goutam; Reck, Theodore and; Schlecht, Erich; Lin, Robert; Deal, William

2012-01-01

The operating frequency of InP high electron mobility transistor (HEMT) based amplifiers has moved well in the submillimeter-wave frequencies over the last couple of years. Working amplifiers with usable gain in waveguide packages has been reported beyond 700 GHz. When cooled cryogenically, they have shown substantial improvement in their noise temperature. This has opened up the real possibility of cryogenic amplifier based heterodyne receivers at submillimeter wavelengths for ground-based, air-borne, and space-based instruments for astrophysics, planetary, and Earth science applications. This paper provides an overview of the science applications at submillimeter wavelengths that will benefit from this technology. It also describes the current state of the InP HEMT based cryogenic amplifier receivers at submillimeter wavelengths.

Radiofrequency testing of satellite segment of simulated 30/20 GHz satellite communications system

NASA Technical Reports Server (NTRS)

Leonard, R. F.; Kerczewski, R.

1985-01-01

A laboratory communications system has been developed that can serve as a test bed for the evaluation of advanced microwave (30/20 GHz) components produced under NASA technology programs. The system will ultimately permit the transmission of a stream of high-rate (220 Mbps) digital data from the originating user, through a ground terminal, through a hardware-simulated satellite, to a receiving ground station, to the receiving user. This report contains the results of radiofrequency testing of the satellite portion of that system. Data presented include output spurious responses, attainable signal-to-noise ratios, a baseline power budget, usable frequency bands, phase and amplitude response data for each of the frequency bands, and the effects of power level variation.

Usability Methods for Ensuring Health Information Technology Safety: Evidence-Based Approaches. Contribution of the IMIA Working Group Health Informatics for Patient Safety.

PubMed

Borycki, E; Kushniruk, A; Nohr, C; Takeda, H; Kuwata, S; Carvalho, C; Bainbridge, M; Kannry, J

2013-01-01

Issues related to lack of system usability and potential safety hazards continue to be reported in the health information technology (HIT) literature. Usability engineering methods are increasingly used to ensure improved system usability and they are also beginning to be applied more widely for ensuring the safety of HIT applications. These methods are being used in the design and implementation of many HIT systems. In this paper we describe evidence-based approaches to applying usability engineering methods. A multi-phased approach to ensuring system usability and safety in healthcare is described. Usability inspection methods are first described including the development of evidence-based safety heuristics for HIT. Laboratory-based usability testing is then conducted under artificial conditions to test if a system has any base level usability problems that need to be corrected. Usability problems that are detected are corrected and then a new phase is initiated where the system is tested under more realistic conditions using clinical simulations. This phase may involve testing the system with simulated patients. Finally, an additional phase may be conducted, involving a naturalistic study of system use under real-world clinical conditions. The methods described have been employed in the analysis of the usability and safety of a wide range of HIT applications, including electronic health record systems, decision support systems and consumer health applications. It has been found that at least usability inspection and usability testing should be applied prior to the widespread release of HIT. However, wherever possible, additional layers of testing involving clinical simulations and a naturalistic evaluation will likely detect usability and safety issues that may not otherwise be detected prior to widespread system release. The framework presented in the paper can be applied in order to develop more usable and safer HIT, based on multiple layers of evidence.

Improved MIMO radar GMTI via cyclic-shift transmission of orthogonal frequency division signals

NASA Astrophysics Data System (ADS)

Li, Fuyou; He, Feng; Dong, Zhen; Wu, Manqing

2018-05-01

Minimum detectable velocity (MDV) and maximum detectable velocity are both important in ground moving target indication (GMTI) systems. Smaller MDV can be achieved by longer baseline via multiple-input multiple-output (MIMO) radar. Maximum detectable velocity is decided by blind velocities associated with carrier frequencies, and blind velocities can be mitigated by orthogonal frequency division signals. However, the scattering echoes from different carrier frequencies are independent, which is not good for improving MDV performance. An improved cyclic-shift transmission is applied in MIMO GMTI system in this paper. MDV performance is improved due to the longer baseline, and maximum detectable velocity performance is improved due to the mitigation of blind velocities via multiple carrier frequencies. The signal model for this mode is established, the principle of mitigating blind velocities with orthogonal frequency division signals is presented; the performance of different MIMO GMTI waveforms is analysed; and the performance of different array configurations is analysed. Simulation results by space-time-frequency adaptive processing proves that our proposed method is a valid way to improve GMTI performance.

Conference Digest LEOS Summer Topical Meetings 1992

DTIC Science & Technology

1992-12-09

of the circuit and determines the maximum frequency of operation. With...operating at a frequency of 335.48 MHz. The resultant timing jitter is determined by sending both pulse trains into a rotating mirror optical correlator with...length of 1.5 un and a gate width of 100 um. have a maximum transconductance of 160 mS/mm and a cut-off frequency of 10 GHz. To determine the

Exploring the Usability of Mobile Apps Supporting Radiologists' Training in Diagnostic Decision Making.

PubMed

Kim, Min Soon; Aro, Michael R; Lage, Kraig J; Ingalls, Kevin L; Sindhwani, Vivek; Markey, Mia K

2016-03-01

The objective of this study was to conduct a usability evaluation of mobile apps for supporting education and training in radiologic diagnostic decision-making processes. Of 381 mobile apps available at two major stores (Google Play and iTunes), eight iOS apps were selected for laboratory-based usability tests. Six staff radiologists completed eight app-specific task sets, using a think-aloud strategy. The triangular methods approach included quantitative performance measures, System Usability Scale (SUS), and qualitative thematic analysis using heuristic usability principles of usability issues. Overall, radiologists achieved higher than 70% success, with favorable SUS scores, in completing the tasks for seven of the eight apps. However, task success rate and SUS score had a weak relation (r = 0.23), indicating that the perceived usability may not reflect the holistic usability of the app. Task analysis and self-report revealed 108 usability issues, which were condensed to 55 unique issues and categorized by nine usability themes and mapped to ten usability heuristics. Nonintuitive functionality (eg, nonintuitive or misleading labels) was the most frequent theme observed, leading to inefficient navigation. These usability findings were consistent with the 13 improvements the radiologists suggested. This study demonstrates the feasibility of usability evaluation of radiology mobile apps and suggests potential improvements in the development of radiology mobile apps. This study also suggests that proficiency with mobile devices may not be equivalent to being an expert user, proficient in using the apps. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Ten factors to consider when developing usability scenarios and tasks for health information technology.

PubMed

Russ, Alissa L; Saleem, Jason J

2018-02-01

The quality of usability testing is highly dependent upon the associated usability scenarios. To promote usability testing as part of electronic health record (EHR) certification, the Office of the National Coordinator (ONC) for Health Information Technology requires that vendors test specific capabilities of EHRs with clinical end-users and report their usability testing process - including the test scenarios used - along with the results. The ONC outlines basic expectations for usability testing, but there is little guidance in usability texts or scientific literature on how to develop usability scenarios for healthcare applications. The objective of this article is to outline key factors to consider when developing usability scenarios and tasks to evaluate computer-interface based health information technologies. To achieve this goal, we draw upon a decade of our experience conducting usability tests with a variety of healthcare applications and a wide range of end-users, to include healthcare professionals as well as patients. We discuss 10 key factors that influence scenario development: objectives of usability testing; roles of end-user(s); target performance goals; evaluation time constraints; clinical focus; fidelity; scenario-related bias and confounders; embedded probes; minimize risks to end-users; and healthcare related outcome measures. For each factor, we present an illustrative example. This article is intended to aid usability researchers and practitioners in their efforts to advance health information technologies. The article provides broad guidance on usability scenario development and can be applied to a wide range of clinical information systems and applications. Published by Elsevier Inc.

Usability flaws of medication-related alerting functions: A systematic qualitative review.

PubMed

Marcilly, Romaric; Ammenwerth, Elske; Vasseur, Francis; Roehrer, Erin; Beuscart-Zéphir, Marie-Catherine

2015-06-01

Medication-related alerting functions may include usability flaws that limit their optimal use. A first step on the way to preventing usability flaws is to understand the characteristics of these usability flaws. This systematic qualitative review aims to analyze the type of usability flaws found in medication-related alerting functions. Papers were searched via PubMed, Scopus and Ergonomics Abstracts databases, along with references lists. Paper selection, data extraction and data analysis was performed by two to three Human Factors experts. Meaningful semantic units representing instances of usability flaws were the main data extracted. They were analyzed through qualitative methods: categorization following general usability heuristics and through an inductive process for the flaws specific to medication-related alerting functions. From the 6380 papers initially identified, 26 met all eligibility criteria. The analysis of the papers identified a total of 168 instances of usability flaws that could be classified into 13 categories of usability flaws representing either violations of general usability principles (i.e. they could be found in any system, e.g. guidance and workload issues) or infractions specific to medication-related alerting functions. The latter refer to issues of low signal-to-noise ratio, incomplete content of alerts, transparency, presentation mode and timing, missing alert features, tasks and control distribution. The list of 168 instances of usability flaws of medication-related alerting functions provides a source of knowledge for checking the usability of medication-related alerting functions during their design and evaluation process and ultimately constructs evidence-based usability design principles for these functions. Copyright © 2015 Elsevier Inc. All rights reserved.

A fluctuating plume dispersion model for the prediction of odour-impact frequencies from continuous stationary sources

NASA Astrophysics Data System (ADS)

Mussio, P.; Gnyp, A. W.; Henshaw, P. F.

A fluctuating plume dispersion model has been developed to facilitate the prediction of odour-impact frequencies in the communities surrounding elevated point sources. The model was used to predict the frequencies of occurrence of odours of various magnitudes for 1 h periods. In addition, the model predicted the maximum odour level. The model was tested with an extensive set of data collected in the residential areas surrounding the paint shop of an automotive assembly plant. Most of the perceived odours in the vicinity of the 64, 46 m high stacks ranged between 2 and 7 odour units and generally persisted for less than 30 s. Ninety-eight different field determinations of odour impact frequencies within 1 km of the plant were conducted during the course of the study. To simplify evaluation, the frequencies of occurrence of different odour levels were summed to give the total frequency of occurrence of all readily detectable (>2 OU) odours. The model provided excellent simulation of the total frequencies of occurrence where the odour was frequent (i.e . readily detectable more than 30% of the time). At lower frequencies of occurrence the model prediction was poor. The stability class did not seem to affect the model's ability to predict field frequency values. However, the model provided excellent predictions of the maximum odour levels without being sensitive to either stability class or distance from the source. Ninety-five percent of the predicted maximum values were within a factor of two of the measured field maximum values.

Usability Flaws in Medication Alerting Systems: Impact on Usage and Work System.

PubMed

Marcilly, R; Ammenwerth, E; Roehrer, E; Pelayo, S; Vasseur, F; Beuscart-Zéphir, M-C

2015-08-13

Previous research has shown that medication alerting systems face usability issues. There has been no previous attempt to systematically explore the consequences of usability flaws in such systems on users (i.e. usage problems) and work systems (i.e. negative outcomes). This paper aims at exploring and synthesizing the consequences of usability flaws in terms of usage problems and negative outcomes on the work system. A secondary analysis of 26 papers included in a prior systematic review of the usability flaws in medication alerting was performed. Usage problems and negative outcomes were extracted and sorted. Links between usability flaws, usage problems, and negative outcomes were also analyzed. Poor usability generates a large variety of consequences. It impacts the user from a cognitive, behavioral, emotional, and attitudinal perspective. Ultimately, usability flaws have negative consequences on the workflow, the effectiveness of the technology, the medication management process, and, more importantly, patient safety. Only few complete pathways leading from usability flaws to negative outcomes were identified. Usability flaws in medication alerting systems impede users, and ultimately their work system, and negatively impact patient safety. Therefore, the usability dimension may act as a hidden explanatory variable that could explain, at least partly, the (absence of) intended outcomes of new technology.

Human Factors in the Large: Experiences from Denmark, Finland and Canada in Moving Towards Regional and National Evaluations of Health Information System Usability. Contribution of the IMIA Human Factors Working Group.

PubMed

Kushniruk, A; Kaipio, J; Nieminen, M; Hyppönen, H; Lääveri, T; Nohr, C; Kanstrup, A M; Berg Christiansen, M; Kuo, M-H; Borycki, E

2014-08-15

The objective of this paper is to explore approaches to understanding the usability of health information systems at regional and national levels. Several different methods are discussed in case studies from Denmark, Finland and Canada. They range from small scale qualitative studies involving usability testing of systems to larger scale national level questionnaire studies aimed at assessing the use and usability of health information systems by entire groups of health professionals. It was found that regional and national usability studies can complement smaller scale usability studies, and that they are needed in order to understand larger trends regarding system usability. Despite adoption of EHRs, many health professionals rate the usability of the systems as low. A range of usability issues have been noted when data is collected on a large scale through use of widely distributed questionnaires and websites designed to monitor user perceptions of usability. As health information systems are deployed on a widespread basis, studies that examine systems used regionally or nationally are required. In addition, collection of large scale data on the usability of specific IT products is needed in order to complement smaller scale studies of specific systems.

Usability Flaws in Medication Alerting Systems: Impact on Usage and Work System

PubMed Central

Ammenwerth, E.; Roehrer, E.; Pelayo, S.; Vasseur, F.; Beuscart-Zéphir, M.-C.

2015-01-01

Summary Objectives Previous research has shown that medication alerting systems face usability issues. There has been no previous attempt to systematically explore the consequences of usability flaws in such systems on users (i.e. usage problems) and work systems (i.e. negative outcomes). This paper aims at exploring and synthesizing the consequences of usability flaws in terms of usage problems and negative outcomes on the work system. Methods A secondary analysis of 26 papers included in a prior systematic review of the usability flaws in medication alerting was performed. Usage problems and negative outcomes were extracted and sorted. Links between usability flaws, usage problems, and negative outcomes were also analyzed. Results Poor usability generates a large variety of consequences. It impacts the user from a cognitive, behavioral, emotional, and attitudinal perspective. Ultimately, usability flaws have negative consequences on the workflow, the effectiveness of the technology, the medication management process, and, more importantly, patient safety. Only few complete pathways leading from usability flaws to negative outcomes were identified. Conclusion Usability flaws in medication alerting systems impede users, and ultimately their work system, and negatively impact patient safety. Therefore, the usability dimension may act as a hidden explanatory variable that could explain, at least partly, the (absence of) intended outcomes of new technology. PMID:26123906

Human Factors in the Large: Experiences from Denmark, Finland and Canada in Moving Towards Regional and National Evaluations of Health Information System Usability

PubMed Central

Kaipio, J.; Nieminen, M.; Hyppönen, H.; Lääveri, T.; Nohr, C.; Kanstrup, A. M.; Berg Christiansen, M.; Kuo, M.-H.; Borycki, E.

2014-01-01

Summary Objectives The objective of this paper is to explore approaches to understanding the usability of health information systems at regional and national levels. Methods Several different methods are discussed in case studies from Denmark, Finland and Canada. They range from small scale qualitative studies involving usability testing of systems to larger scale national level questionnaire studies aimed at assessing the use and usability of health information systems by entire groups of health professionals. Results It was found that regional and national usability studies can complement smaller scale usability studies, and that they are needed in order to understand larger trends regarding system usability. Despite adoption of EHRs, many health professionals rate the usability of the systems as low. A range of usability issues have been noted when data is collected on a large scale through use of widely distributed questionnaires and websites designed to monitor user perceptions of usability. Conclusion As health information systems are deployed on a widespread basis, studies that examine systems used regionally or nationally are required. In addition, collection of large scale data on the usability of specific IT products is needed in order to complement smaller scale studies of specific systems. PMID:25123725

Improving Public Relations Web Sites through Usability Research.

ERIC Educational Resources Information Center

Hallahan, Kirk

2001-01-01

Argues that usability research has particular relevance for enhancing the effectiveness of websites. Examines the nature and value of usability research, and the elements of an effective website based on usability principles. (SR)

Grain refinement control in TIG arc welding

NASA Technical Reports Server (NTRS)

Iceland, W. F.; Whiffen, E. L. (Inventor)

1975-01-01

A method for controlling grain size and weld puddle agitation in a tungsten electrode inert gas welding system to produce fine, even grain size and distribution is disclosed. In the method the frequency of dc welding voltage pulses supplied to the welding electrode is varied over a preselected frequency range and the arc gas voltage is monitored. At some frequency in the preselected range the arc gas voltage will pass through a maximum. By maintaining the operating frequency of the system at this value, maximum weld puddle agitation and fine grain structure are produced.

Applying usability methods to identify health literacy issues: an example using a Personal Health Record.

PubMed

Monkman, Helen; Kushniruk, Andre

2013-01-01

The prevalence of consumer health information systems is increasing. However, usability and health literacy impact both the value and adoption of these systems. Health literacy and usability are closely related in that systems may not be used accurately if users cannot understand the information therein. Thus, it is imperative to focus on mitigating the demands on health literacy in consumer health information systems. This study modified two usability evaluation methods (heuristic evaluation and usability testing) to incorporate the identification of potential health literacy issues in a Personal Health Record (PHR). Heuristic evaluation is an analysis of a system performed by a usability specialist who evaluates how well the system abides by usability principles. In contrast, a usability test involves a post hoc analysis of a representative user interacting with the system. These two methods revealed several health literacy issues and suggestions to ameliorate them were made. Thus, it was demonstrated that usability methods could be successfully augmented for the purpose of investigating health literacy issues. To improve users' health knowledge, the adoption of consumer health information systems, and the accuracy of the information contained therein, it is encouraged that usability methods be applied with an added focus on health literacy.

Usability evaluation techniques in mobile commerce applications: A systematic review

NASA Astrophysics Data System (ADS)

Hussain, Azham; Mkpojiogu, Emmanuel O. C.

2016-08-01

Obviously, there are a number of literatures concerning the usability of mobile commerce (m-commerce) applications and related areas, but they do not adequately provide knowledge about usability techniques used in most of the empirical usability evaluation for m-commerce application. Therefore, this paper is aimed at producing the usability techniques frequently used in the aspect of usability evaluation for m-commerce applications. To achieve the stated objective, systematic literature review was employed. Sixty seven papers were downloaded in usability evaluation for m-commerce and related areas; twenty one most relevant studies were selected for review in order to extract the appropriate information. The results from the review shows that heuristic evaluation, formal test and think aloud methods are the most commonly used methods in m-commerce application in comparison to cognitive walkthrough and the informal test methods. Moreover, most of the studies applied control experiment (33.3% of the total studies); other studies that applied case study for usability evaluation are 14.28%. The results from this paper provide additional knowledge to the usability practitioners and research community for the current state and use of usability techniques in m-commerce application.

The current status of usability studies of information technologies in China: a systematic study.

PubMed

Lei, Jianbo; Xu, Lufei; Meng, Qun; Zhang, Jiajie; Gong, Yang

2014-01-01

To systematically review and analyze the current status and characteristics of usability studies in China in the field of information technology in general and in the field of healthcare in particular. We performed a quantitative literature analysis in three major Chinese academic databases and one English language database using Chinese search terms equivalent to the concept of usability. Six hundred forty-seven publications were selected for analysis. We found that in China the literature on usability in the field of information technology began in 1994 and increased thereafter. The usability definitions from ISO 9241-11:1998 and Nielsen (1993) have been widely recognized and cited. Authors who have published several publications are rare. Fourteen journals have a publishing rate over 1%. Only nine publications about HIT were identified. China's usability research started relatively late. There is a lack of organized research teams and dedicated usability journals. High-impact theoretical studies are scarce. On the application side, no original and systematic research frameworks have been developed. The understanding and definition of usability is not well synchronized with international norms. Besides, usability research in HIT is rare. More human and material resources need to be invested in China's usability research, particularly in HIT.

Usability testing for the rest of us: the application of discount usability principles in the development of an online communications assessment application.

PubMed

Brock, Douglas; Kim, Sara; Palmer, Odawni; Gallagher, Thomas; Holmboe, Eric

2013-01-01

Usability evaluation provides developers and educators with the means to understand user needs, improve overall product utility, and increase user satisfaction. The application of "discount usability" principles developed to make usability testing more practical and useful may improve user experience at minimal cost and require little existing expertise to conduct. We describe an application of discount usability to a high-fidelity online communications assessment application developed by the University of Washington for the American Board of Internal Medicine. Eight internal medicine physicians completed a discount usability test. Sessions were recorded and the videos analyzed for significant usability concerns. Concerns were identified, summarized, discussed, and prioritized by the authors in collaboration with the software developers before implementing any changes to the interface. Thirty-eight significant usability issues were detected and four technical problems were identified. Each issue was responded to through modification of the software, by providing additional instruction, or delayed for a later version to be developed. Discount usability can be easily implemented in academic developmental activities. Our study resulted in the discovery and remediation of significant user problems, in addition to giving important insight into the novel methods built into the application.

Evaluation of a Dry EEG System for Application of Passive Brain-Computer Interfaces in Autonomous Driving

PubMed Central

Zander, Thorsten O.; Andreessen, Lena M.; Berg, Angela; Bleuel, Maurice; Pawlitzki, Juliane; Zawallich, Lars; Krol, Laurens R.; Gramann, Klaus

2017-01-01

We tested the applicability and signal quality of a 16 channel dry electroencephalography (EEG) system in a laboratory environment and in a car under controlled, realistic conditions. The aim of our investigation was an estimation how well a passive Brain-Computer Interface (pBCI) can work in an autonomous driving scenario. The evaluation considered speed and accuracy of self-applicability by an untrained person, quality of recorded EEG data, shifts of electrode positions on the head after driving-related movements, usability, and complexity of the system as such and wearing comfort over time. An experiment was conducted inside and outside of a stationary vehicle with running engine, air-conditioning, and muted radio. Signal quality was sufficient for standard EEG analysis in the time and frequency domain as well as for the use in pBCIs. While the influence of vehicle-induced interferences to data quality was insignificant, driving-related movements led to strong shifts in electrode positions. In general, the EEG system used allowed for a fast self-applicability of cap and electrodes. The assessed usability of the system was still acceptable while the wearing comfort decreased strongly over time due to friction and pressure to the head. From these results we conclude that the evaluated system should provide the essential requirements for an application in an autonomous driving context. Nevertheless, further refinement is suggested to reduce shifts of the system due to body movements and increase the headset's usability and wearing comfort. PMID:28293184

Evaluation of a Dry EEG System for Application of Passive Brain-Computer Interfaces in Autonomous Driving.

PubMed

Zander, Thorsten O; Andreessen, Lena M; Berg, Angela; Bleuel, Maurice; Pawlitzki, Juliane; Zawallich, Lars; Krol, Laurens R; Gramann, Klaus

2017-01-01

We tested the applicability and signal quality of a 16 channel dry electroencephalography (EEG) system in a laboratory environment and in a car under controlled, realistic conditions. The aim of our investigation was an estimation how well a passive Brain-Computer Interface (pBCI) can work in an autonomous driving scenario. The evaluation considered speed and accuracy of self-applicability by an untrained person, quality of recorded EEG data, shifts of electrode positions on the head after driving-related movements, usability, and complexity of the system as such and wearing comfort over time. An experiment was conducted inside and outside of a stationary vehicle with running engine, air-conditioning, and muted radio. Signal quality was sufficient for standard EEG analysis in the time and frequency domain as well as for the use in pBCIs. While the influence of vehicle-induced interferences to data quality was insignificant, driving-related movements led to strong shifts in electrode positions. In general, the EEG system used allowed for a fast self-applicability of cap and electrodes. The assessed usability of the system was still acceptable while the wearing comfort decreased strongly over time due to friction and pressure to the head. From these results we conclude that the evaluated system should provide the essential requirements for an application in an autonomous driving context. Nevertheless, further refinement is suggested to reduce shifts of the system due to body movements and increase the headset's usability and wearing comfort.

Confirming, Classifying, and Prioritizing Needed Over-the-Bed Table Improvements via Methodological Triangulation.

PubMed

Manganelli, Joe; Threatt, Anthony; Brooks, Johnell O; Healy, Stan; Merino, Jessica; Yanik, Paul; Walker, Ian; Green, Keith

2014-01-01

This article presents the results of a qualitative study that confirmed, classified, and prioritized user needs for the design of a more useful, usable, and actively assistive over-the-bed table. Manganelli et al. (2014) generated a list of 74 needs for use in developing an actively assistive over-the-bed table. This present study assesses the value and importance of those needs. Fourteen healthcare subject matter experts and eight research and design subject matter experts engaged in a participatory and iterative research and design process. A mixed methods qualitative approach used methodological triangulation to confirm the value of the findings and ratings to establish importance. Open and closed card sorts and a Delphi study were used. Data analysis methods included frequency analysis, content analysis, and a modified Kano analysis. A table demonstrating the needs that are of high importance to both groups of subject matter experts and classification of the design challenges each represents was produced. Through this process, the list of 74 needs was refined to the 37 most important need statements for both groups. Designing a more useful, usable, and actively assistive over-the-bed table is primarily about the ability to position it optimally with respect to the user for any task, as well as improving ease of use and usability. It is also important to make explicit and discuss the differences in priorities and perspectives demonstrated between research and design teams and their clients. © 2014 Vendome Group, LLC.

Earthdata Search Usability Study Process

NASA Technical Reports Server (NTRS)

Reese, Mark

2016-01-01

User experience (UX) design is the process of enhancing user satisfaction by improving various aspects of the user's interaction with an application or website. One aspect of UX design is usability, or the extent to which an application can be used to to accomplish tasks efficiently, effectively, and with satisfaction. NASA's Earthdata Search Client recently underwent a focused usability testing project to measure usability and gain valuable user feedback and insights to increase usability for its end-users. This presentation focuses on the process by which the usability tests were administered and the lessons learned throughout the process.

Qualitative review of usability problems in health information systems for radiology.

PubMed

Dias, Camila Rodrigues; Pereira, Marluce Rodrigues; Freire, André Pimenta

2017-12-01

Radiology processes are commonly supported by Radiology Information System (RIS), Picture Archiving and Communication System (PACS) and other software for radiology. However, these information technologies can present usability problems that affect the performance of radiologists and physicians, especially considering the complexity of the tasks involved. The purpose of this study was to extract, classify and analyze qualitatively the usability problems in PACS, RIS and other software for radiology. A systematic review was performed to extract usability problems reported in empirical usability studies in the literature. The usability problems were categorized as violations of Nielsen and Molich's usability heuristics. The qualitative analysis indicated the causes and the effects of the identified usability problems. From the 431 papers initially identified, 10 met the study criteria. The analysis of the papers identified 90 instances of usability problems, classified into categories corresponding to established usability heuristics. The five heuristics with the highest number of instances of usability problems were "Flexibility and efficiency of use", "Consistency and standards", "Match between system and the real world", "Recognition rather than recall" and "Help and documentation", respectively. These problems can make the interaction time consuming, causing delays in tasks, dissatisfaction, frustration, preventing users from enjoying all the benefits and functionalities of the system, as well as leading to more errors and difficulties in carrying out clinical analyses. Furthermore, the present paper showed a lack of studies performed on systems for radiology, especially usability evaluations using formal methods of evaluation involving the final users. Copyright © 2017 Elsevier Inc. All rights reserved.

Design and implementation of a hospital-based usability laboratory: insights from a Department of Veterans Affairs laboratory for health information technology.

PubMed

Russ, Alissa L; Weiner, Michael; Russell, Scott A; Baker, Darrell A; Fahner, W Jeffrey; Saleem, Jason J

2012-12-01

Although the potential benefits of more usable health information technologies (HIT) are substantial-reduced HIT support costs, increased work efficiency, and improved patient safety--human factors methods to improve usability are rarely employed. The US Department of Veterans Affairs (VA) has emerged as an early leader in establishing usability laboratories to inform the design of HIT, including its electronic health record. Experience with a usability laboratory at a VA Medical Center provides insights on how to design, implement, and leverage usability laboratories in the health care setting. The VA Health Services Research and Development Service Human-Computer Interaction & Simulation Laboratory emerged as one of the first VA usability laboratories and was intended to provide research-based findings about HIT designs. This laboratory supports rapid prototyping, formal usability testing, and analysis tools to assess existing technologies, alternative designs, and potential future technologies. RESULTS OF IMPLEMENTATION: Although the laboratory has maintained a research focus, it has become increasingly integrated with VA operations, both within the medical center and on a national VA level. With this resource, data-driven recommendations have been provided for the design of HIT applications before and after implementation. The demand for usability testing of HIT is increasing, and information on how to develop usability laboratories for the health care setting is often needed. This article may assist other health care organizations that want to invest in usability resources to improve HIT. The establishment and utilization of usability laboratories in the health care setting may improve HIT designs and promote safe, high-quality care for patients.

Feasibility of a Web-Based Self-Management Intervention for Intermittent Urinary Catheter Users with Spinal Cord Injury

PubMed Central

Wilde, Mary H.; McMahon, James M.; Fairbanks, Eileen; Brasch, Judith; Parshall, Robert; Zhang, Feng; Miner, Sarah; Thayer, Deborah; Schneiderman, Dan; Harrington, Brian

2016-01-01

Purpose The purpose of this study was to evaluate the feasibility of a new web-based intermittent catheter self-management intervention. Design We tested the acceptability and usability of intervention components, which included multiple web-based materials (an online urinary diary adapted for mobile phone use and an educational booklet), three phone calls with a nurse, and a peer led discussion forum. Subjects and setting Thirty adults with spinal cord injury using an intermittent catheter for bladder drainage were enrolled; 26 participants received the nurses’ phone based consultations. Methods Preliminary effectiveness of new self-efficacy and self-management scales were evaluated using baseline and three month online surveys. Participants’ perceived value of the intervention components, self-management changes, and suggestions were assessed with data from the three month surveys followed by brief tape-recorded interviews. Results Several catheter practices improved somewhat over three months including. The frequency of catheterizations every 4–6 hours increased from 71% to 77%. Self-management of neurogenic bladder dysfunction increased significantly (P= .032); participant comments indicated that fluid intake was the biggest change. Catheter related self-efficacy and quality of life scores increased. The frequency of urinary tract infection and pain did not change significantly. For feasibility, intervention components, with the exception of the forum, were rated highly by the majority of participants for usefulness, satisfaction (desired information), and web-based usability. Conclusion Further testing of this intervention is recommended in a multi-site randomized clinical trial. PMID:27488740

Maximum Dynamic Lower-Limb Strength Was Maintained During 24-Week Reduced Training Frequency in Previously Sedentary Older Women.

PubMed

Walker, Simon; Serrano, Javier; Van Roie, Evelien

2018-04-01

Walker, S, Serrano, J, and Van Roie, E. Maximum dynamic lower-limb strength was maintained during 24-week reduced training frequency in previously sedentary older women. J Strength Cond Res 32(4): 1063-1071, 2018-There is little study into the effects of reducing strength training below the recommended twice weekly frequency, particularly in older women, despite the possibility that individuals will encounter periods of reduced training frequency. The purpose of the present study was to determine the effects of a period of reduced training frequency on maximum strength and muscle mass of the lower limbs in comparison with the recommended training frequency of twice per week. After an initial 12-week period, where all subjects trained twice per week, a reduced strength training group (RST) trained once per week, whereas another strength training group (ST) continued to train twice per week for 24 weeks. A nontraining age-matched control group (CON) was used for comparison. All subjects were tested for leg press 1-repetition maximum (1RM), electromyogram (EMG) amplitude of vastus lateralis and medialis, and quadriceps cross-sectional area (CSA) measured by panoramic ultrasound at weeks 0, 12, and 36. Both ST and RST continued to increase 1RM during the reduced training frequency period compared with control (∼8% and ∼5% vs. ∼-3%, respectively; p ≤ 0.05). Accompanying these changes were significant increases in EMG amplitude in both ST and RST (p ≤ 0.05). However, the initial gains in quadriceps CSA made from week 0 to week 12 in RST were lost when training once per week (RST ∼-5%). Therefore, reduced training frequency in this population does not adversely affect maximum strength or muscle activity but can negatively affect muscle mass, even reversing training-induced gains. Older individuals not training at least twice per week may compromise potential increases in muscle mass, important in counteracting effects of aging.

An Iterative, Mixed Usability Approach Applied to the Telekit System from the Danish TeleCare North Trial

PubMed Central

Schaarup, Clara; Hejlesen, Ole Kristian

2016-01-01

Objective. The aim of the present study is to evaluate the usability of the telehealth system, coined Telekit, by using an iterative, mixed usability approach. Materials and Methods. Ten double experts participated in two heuristic evaluations (HE1, HE2), and 11 COPD patients attended two think-aloud tests. The double experts identified usability violations and classified them into Jakob Nielsen's heuristics. These violations were then translated into measurable values on a scale of 0 to 4 indicating degree of severity. In the think-aloud tests, COPD participants were invited to verbalise their thoughts. Results. The double experts identified 86 usability violations in HE1 and 101 usability violations in HE2. The majority of the violations were rated in the 0–2 range. The findings from the think-aloud tests resulted in 12 themes and associated examples regarding the usability of the Telekit system. The use of the iterative, mixed usability approach produced both quantitative and qualitative results. Conclusion. The iterative, mixed usability approach yields a strong result owing to the high number of problems identified in the tests because the double experts and the COPD participants focus on different aspects of Telekit's usability. This trial is registered with Clinicaltrials.gov, NCT01984840, November 14, 2013. PMID:27974888

Beyond Effectiveness: A Pragmatic Evaluation Framework for Learning and Continuous Quality Improvement of e-Learning Interventions in Healthcare.

PubMed

Dafalla, Tarig Dafalla Mohamed; Kushniruk, Andre W; Borycki, Elizabeth M

2015-01-01

A pragmatic evaluation framework for evaluating the usability and usefulness of an e-learning intervention for a patient clinical information scheduling system is presented in this paper. The framework was conceptualized based on two different but related concepts (usability and usefulness) and selection of appropriate and valid methods of data collection and analysis that included: (1) Low-Cost Rapid Usability Engineering (LCRUE), (2) Cognitive Task Analysis (CTA), (3) Heuristic Evaluation (HE) criteria for web-based learning, and (4) Software Usability Measurement Inventory (SUMI). The results of the analysis showed some areas where usability that were related to General Interface Usability (GIU), instructional design and content was problematic; some of which might account for the poorly rated aspects of usability when subjectively measured. This paper shows that using a pragmatic framework can be a useful way, not only for measuring the usability and usefulness, but also for providing a practical objective evidences for learning and continuous quality improvement of e-learning systems. The findings should be of interest to educators, developers, designers, researchers, and usability practitioners involved in the development of e-learning systems in healthcare. This framework could be an appropriate method for assessing the usability, usefulness and safety of health information systems both in the laboratory and in the clinical context.

A methodology for evaluating the usability of audiovisual consumer electronic products.

PubMed

Kwahk, Jiyoung; Han, Sung H

2002-09-01

Usability evaluation is now considered an essential procedure in consumer product development. Many studies have been conducted to develop various techniques and methods of usability evaluation hoping to help the evaluators choose appropriate methods. However, planning and conducting usability evaluation requires considerations of a number of factors surrounding the evaluation process including the product, user, activity, and environmental characteristics. In this perspective, this study suggested a new methodology of usability evaluation through a simple, structured framework. The framework was outlined by three major components: the interface features of a product as design variables, the evaluation context consisting of user, product, activity, and environment as context variables, and the usability measures as dependent variables. Based on this framework, this study established methods to specify the product interface features, to define evaluation context, and to measure usability. The effectiveness of this methodology was demonstrated through case studies in which the usability of audiovisual products was evaluated by using the methods developed in this study. This study is expected to help the usability practitioners in consumer electronics industry in various ways. Most directly, it supports the evaluators' plan and conduct usability evaluation sessions in a systematic and structured manner. In addition, it can be applied to other categories of consumer products (such as appliances, automobiles, communication devices, etc.) with minor modifications as necessary.

OPTIMIZING USABILITY OF AN ECONOMIC DECISION SUPPORT TOOL: PROTOTYPE OF THE EQUIPT TOOL.

PubMed

Cheung, Kei Long; Hiligsmann, Mickaël; Präger, Maximilian; Jones, Teresa; Józwiak-Hagymásy, Judit; Muñoz, Celia; Lester-George, Adam; Pokhrel, Subhash; López-Nicolás, Ángel; Trapero-Bertran, Marta; Evers, Silvia M A A; de Vries, Hein

2018-01-01

Economic decision-support tools can provide valuable information for tobacco control stakeholders, but their usability may impact the adoption of such tools. This study aims to illustrate a mixed-method usability evaluation of an economic decision-support tool for tobacco control, using the EQUIPT ROI tool prototype as a case study. A cross-sectional mixed methods design was used, including a heuristic evaluation, a thinking aloud approach, and a questionnaire testing and exploring the usability of the Return of Investment tool. A total of sixty-six users evaluated the tool (thinking aloud) and completed the questionnaire. For the heuristic evaluation, four experts evaluated the interface. In total twenty-one percent of the respondents perceived good usability. A total of 118 usability problems were identified, from which twenty-six problems were categorized as most severe, indicating high priority to fix them before implementation. Combining user-based and expert-based evaluation methods is recommended as these were shown to identify unique usability problems. The evaluation provides input to optimize usability of a decision-support tool, and may serve as a vantage point for other developers to conduct usability evaluations to refine similar tools before wide-scale implementation. Such studies could reduce implementation gaps by optimizing usability, enhancing in turn the research impact of such interventions.

An Iterative, Mixed Usability Approach Applied to the Telekit System from the Danish TeleCare North Trial.

PubMed

Lilholt, Pernille Heyckendorff; Schaarup, Clara; Hejlesen, Ole Kristian

2016-01-01

Objective . The aim of the present study is to evaluate the usability of the telehealth system, coined Telekit, by using an iterative, mixed usability approach. Materials and Methods . Ten double experts participated in two heuristic evaluations (HE1, HE2), and 11 COPD patients attended two think-aloud tests. The double experts identified usability violations and classified them into Jakob Nielsen's heuristics. These violations were then translated into measurable values on a scale of 0 to 4 indicating degree of severity. In the think-aloud tests, COPD participants were invited to verbalise their thoughts. Results . The double experts identified 86 usability violations in HE1 and 101 usability violations in HE2. The majority of the violations were rated in the 0-2 range. The findings from the think-aloud tests resulted in 12 themes and associated examples regarding the usability of the Telekit system. The use of the iterative, mixed usability approach produced both quantitative and qualitative results. Conclusion . The iterative, mixed usability approach yields a strong result owing to the high number of problems identified in the tests because the double experts and the COPD participants focus on different aspects of Telekit's usability. This trial is registered with Clinicaltrials.gov, NCT01984840, November 14, 2013.

Combining usability evaluations to highlight the chain that leads from usability flaws to usage problems and then negative outcomes.

PubMed

Watbled, Ludivine; Marcilly, Romaric; Guerlinger, Sandra; Bastien, J-M Christian; Beuscart-Zéphir, Marie-Catherine; Beuscart, Régis

2018-02-01

Poor usability of health technology is thought to diminish work system performance, increase error rates and, potentially, harm patients. The present study (i) used a combination of usability evaluation methods to highlight the chain that leads from usability flaws to usage problems experienced by users and, ultimately, to negative patient outcomes, and (ii) validated this approach by studying two different discharge summary production systems. To comply with quality guidelines, the process of drafting and sending discharge summaries is increasingly being automated. However, the usability of these systems may modify their impact (or the absence thereof) in terms of production times and quality, and must therefore be evaluated. Here, we applied three successive techniques for usability evaluation (heuristic evaluation, user testing and field observation) to two discharge summary production systems (underpinned by different technologies). The systems' main usability flaws led respectively to an increase in the time need to produce a discharge summary and the risk of patient misidentification. Our results are discussed with regard to the possibility of linking the usability flaws, usage problems and the negative outcomes by successively applying three methods for evaluating usability (heuristic evaluation, user testing and in situ observations) throughout the system development life cycle. Copyright © 2018 Elsevier Inc. All rights reserved.

The Current Status of Usability Studies of Information Technologies in China: A Systematic Study

PubMed Central

Lei, Jianbo; Xu, Lufei; Meng, Qun; Zhang, Jiajie; Gong, Yang

2014-01-01

Objectives. To systematically review and analyze the current status and characteristics of usability studies in China in the field of information technology in general and in the field of healthcare in particular. Methods. We performed a quantitative literature analysis in three major Chinese academic databases and one English language database using Chinese search terms equivalent to the concept of usability. Results. Six hundred forty-seven publications were selected for analysis. We found that in China the literature on usability in the field of information technology began in 1994 and increased thereafter. The usability definitions from ISO 9241-11:1998 and Nielsen (1993) have been widely recognized and cited. Authors who have published several publications are rare. Fourteen journals have a publishing rate over 1%. Only nine publications about HIT were identified. Discussions. China's usability research started relatively late. There is a lack of organized research teams and dedicated usability journals. High-impact theoretical studies are scarce. On the application side, no original and systematic research frameworks have been developed. The understanding and definition of usability is not well synchronized with international norms. Besides, usability research in HIT is rare. Conclusions. More human and material resources need to be invested in China's usability research, particularly in HIT. PMID:25050362

To twist or poke? A method for identifying usability issues with the rotary controller and touch screen for control of in-vehicle information systems.

PubMed

Harvey, Catherine; Stanton, Neville A; Pickering, Carl A; McDonald, Mike; Zheng, Pengjun

2011-07-01

In-vehicle information systems (IVIS) can be controlled by the user via direct or indirect input devices. In order to develop the next generation of usable IVIS, designers need to be able to evaluate and understand the usability issues associated with these two input types. The aim of this study was to investigate the effectiveness of a set of empirical usability evaluation methods for identifying important usability issues and distinguishing between the IVIS input devices. A number of usability issues were identified and their causal factors have been explored. These were related to the input type, the structure of the menu/tasks and hardware issues. In particular, the translation between inputs and on-screen actions and a lack of visual feedback for menu navigation resulted in lower levels of usability for the indirect device. This information will be useful in informing the design of new IVIS, with improved usability. STATEMENT OF RELEVANCE: This paper examines the use of empirical methods for distinguishing between direct and indirect IVIS input devices and identifying usability issues. Results have shown that the characteristics of indirect input devices produce more serious usability issues, compared with direct devices and can have a negative effect on the driver-vehicle interaction.

Analysis of the aerodynamic interaction between two plunging plates in tandem at low Reynolds number for maximum propulsive efficiency

NASA Astrophysics Data System (ADS)

Ortega-Casanova, Joaquin; Fernandez-Feria, Ramon

2015-11-01

The thrust generated by two heaving plates in tandem is analysed for two particular sets of configurations of interest in forward flight: a plunging leading plate with the trailing plate at rest, and the two plates heaving with the same frequency and amplitude, but varying the phase difference. The thrust efficiency of the leading plate is augmented in relation to a single plate heaving with the same frequency and amplitude in most cases. In the first configuration, we characterize the range of nondimensional heaving frequencies and amplitudes of the leading plate for which the stationary trailing plate contributes positively to the global thrust. The maximum global thrust efficiency, reached for an advance ratio slightly less than unity and a reduced frequency close to 5, is about the same as the maximum efficiency for an isolated plate. But for low frequencies the tandem configuration with the trailing plate at rest is more thrust efficient than the isolated plate. In the second configuration, we find that the maximum thrust efficiency is reached for a phase lag of 180o (counterstroking), particularly for an advance ratio unity and a reduced frequency 4.4, and it is practically the same as in the other configuration and that for a single plate. Supported by the Ministerio de Economía y Competitividad of Spain Grant no. DPI2013-40479-P.

A Web-Based Graphical Food Frequency Assessment System: Design, Development and Usability Metrics.

PubMed

Franco, Rodrigo Zenun; Alawadhi, Balqees; Fallaize, Rosalind; Lovegrove, Julie A; Hwang, Faustina

2017-05-08

Food frequency questionnaires (FFQs) are well established in the nutrition field, but there remain important questions around how to develop online tools in a way that can facilitate wider uptake. Also, FFQ user acceptance and evaluation have not been investigated extensively. This paper presents a Web-based graphical food frequency assessment system that addresses challenges of reproducibility, scalability, mobile friendliness, security, and usability and also presents the utilization metrics and user feedback from a deployment study. The application design employs a single-page application Web architecture with back-end services (database, authentication, and authorization) provided by Google Firebase's free plan. Its design and responsiveness take advantage of the Bootstrap framework. The FFQ was deployed in Kuwait as part of the EatWellQ8 study during 2016. The EatWellQ8 FFQ contains 146 food items (including drinks). Participants were recruited in Kuwait without financial incentive. Completion time was based on browser timestamps and usability was measured using the System Usability Scale (SUS), scoring between 0 and 100. Products with a SUS higher than 70 are considered to be good. A total of 235 participants created accounts in the system, and 163 completed the FFQ. Of those 163 participants, 142 reported their gender (93 female, 49 male) and 144 reported their date of birth (mean age of 35 years, range from 18-65 years). The mean completion time for all FFQs (n=163), excluding periods of interruption, was 14.2 minutes (95% CI 13.3-15.1 minutes). Female participants (n=93) completed in 14.1 minutes (95% CI 12.9-15.3 minutes) and male participants (n=49) completed in 14.3 minutes (95% CI 12.6-15.9 minutes). Participants using laptops or desktops (n=69) completed the FFQ in an average of 13.9 minutes (95% CI 12.6-15.1 minutes) and participants using smartphones or tablets (n=91) completed in an average of 14.5 minutes (95% CI 13.2-15.8 minutes). The median SUS score (n=141) was 75.0 (interquartile range [IQR] 12.5), and 84% of the participants who completed the SUS classified the system either "good" (n=50) or "excellent" (n=69). Considering only participants using smartphones or tablets (n=80), the median score was 72.5 (IQR 12.5), slightly below the SUS median for desktops and laptops (n=58), which was 75.0 (IQR 12.5). No significant differences were found between genders or age groups (below and above the median) for the SUS or completion time. Taking into account all the requirements, the deployment used professional cloud computing at no cost, and the resulting system had good user acceptance. The results for smartphones/tablets were comparable with desktops/laptops. This work has potential to promote wider uptake of online tools that can assess dietary intake at scale. ©Rodrigo Zenun Franco, Balqees Alawadhi, Rosalind Fallaize, Julie A Lovegrove, Faustina Hwang. Originally published in JMIR Human Factors (http://humanfactors.jmir.org), 08.05.2017.

Direct comparison of phase-sensitive vibrational sum frequency generation with maximum entropy method: case study of water.

PubMed

de Beer, Alex G F; Samson, Jean-Sebastièn; Hua, Wei; Huang, Zishuai; Chen, Xiangke; Allen, Heather C; Roke, Sylvie

2011-12-14

We present a direct comparison of phase sensitive sum-frequency generation experiments with phase reconstruction obtained by the maximum entropy method. We show that both methods lead to the same complex spectrum. Furthermore, we discuss the strengths and weaknesses of each of these methods, analyzing possible sources of experimental and analytical errors. A simulation program for maximum entropy phase reconstruction is available at: http://lbp.epfl.ch/. © 2011 American Institute of Physics

Using a fuzzy comprehensive evaluation method to determine product usability: A test case

PubMed Central

Zhou, Ronggang; Chan, Alan H. S.

2016-01-01

BACKGROUND: In order to take into account the inherent uncertainties during product usability evaluation, Zhou and Chan [1] proposed a comprehensive method of usability evaluation for products by combining the analytic hierarchy process (AHP) and fuzzy evaluation methods for synthesizing performance data and subjective response data. This method was designed to provide an integrated framework combining the inevitable vague judgments from the multiple stages of the product evaluation process. OBJECTIVE AND METHODS: In order to illustrate the effectiveness of the model, this study used a summative usability test case to assess the application and strength of the general fuzzy usability framework. To test the proposed fuzzy usability evaluation framework [1], a standard summative usability test was conducted to benchmark the overall usability of a specific network management software. Based on the test data, the fuzzy method was applied to incorporate both the usability scores and uncertainties involved in the multiple components of the evaluation. Then, with Monte Carlo simulation procedures, confidence intervals were used to compare the reliabilities among the fuzzy approach and two typical conventional methods combining metrics based on percentages. RESULTS AND CONCLUSIONS: This case study showed that the fuzzy evaluation technique can be applied successfully for combining summative usability testing data to achieve an overall usability quality for the network software evaluated. Greater differences of confidence interval widths between the method of averaging equally percentage and weighted evaluation method, including the method of weighted percentage averages, verified the strength of the fuzzy method. PMID:28035942

Using a fuzzy comprehensive evaluation method to determine product usability: A test case.

PubMed

Zhou, Ronggang; Chan, Alan H S

2017-01-01

In order to take into account the inherent uncertainties during product usability evaluation, Zhou and Chan [1] proposed a comprehensive method of usability evaluation for products by combining the analytic hierarchy process (AHP) and fuzzy evaluation methods for synthesizing performance data and subjective response data. This method was designed to provide an integrated framework combining the inevitable vague judgments from the multiple stages of the product evaluation process. In order to illustrate the effectiveness of the model, this study used a summative usability test case to assess the application and strength of the general fuzzy usability framework. To test the proposed fuzzy usability evaluation framework [1], a standard summative usability test was conducted to benchmark the overall usability of a specific network management software. Based on the test data, the fuzzy method was applied to incorporate both the usability scores and uncertainties involved in the multiple components of the evaluation. Then, with Monte Carlo simulation procedures, confidence intervals were used to compare the reliabilities among the fuzzy approach and two typical conventional methods combining metrics based on percentages. This case study showed that the fuzzy evaluation technique can be applied successfully for combining summative usability testing data to achieve an overall usability quality for the network software evaluated. Greater differences of confidence interval widths between the method of averaging equally percentage and weighted evaluation method, including the method of weighted percentage averages, verified the strength of the fuzzy method.

Corrected Implicit Monte Carlo

DOE PAGES

Cleveland, Mathew Allen; Wollaber, Allan Benton

2018-01-02

Here in this work we develop a set of nonlinear correction equations to enforce a consistent time-implicit emission temperature for the original semi-implicit IMC equations. We present two possible forms of correction equations: one results in a set of non-linear, zero-dimensional, non-negative, explicit correction equations, and the other results in a non-linear, non-negative, Boltzman transport correction equation. The zero-dimensional correction equations adheres to the maximum principle for the material temperature, regardless of frequency-dependence, but does not prevent maximum principle violation in the photon intensity, eventually leading to material overheating. The Boltzman transport correction guarantees adherence to the maximum principle formore » frequency-independent simulations, at the cost of evaluating a reduced source non-linear Boltzman equation. Finally, we present numerical evidence suggesting that the Boltzman transport correction, in its current form, significantly improves time step limitations but does not guarantee adherence to the maximum principle for frequency-dependent simulations.« less

Corrected implicit Monte Carlo

NASA Astrophysics Data System (ADS)

Cleveland, M. A.; Wollaber, A. B.

2018-04-01

In this work we develop a set of nonlinear correction equations to enforce a consistent time-implicit emission temperature for the original semi-implicit IMC equations. We present two possible forms of correction equations: one results in a set of non-linear, zero-dimensional, non-negative, explicit correction equations, and the other results in a non-linear, non-negative, Boltzman transport correction equation. The zero-dimensional correction equations adheres to the maximum principle for the material temperature, regardless of frequency-dependence, but does not prevent maximum principle violation in the photon intensity, eventually leading to material overheating. The Boltzman transport correction guarantees adherence to the maximum principle for frequency-independent simulations, at the cost of evaluating a reduced source non-linear Boltzman equation. We present numerical evidence suggesting that the Boltzman transport correction, in its current form, significantly improves time step limitations but does not guarantee adherence to the maximum principle for frequency-dependent simulations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cleveland, Mathew Allen; Wollaber, Allan Benton

Here in this work we develop a set of nonlinear correction equations to enforce a consistent time-implicit emission temperature for the original semi-implicit IMC equations. We present two possible forms of correction equations: one results in a set of non-linear, zero-dimensional, non-negative, explicit correction equations, and the other results in a non-linear, non-negative, Boltzman transport correction equation. The zero-dimensional correction equations adheres to the maximum principle for the material temperature, regardless of frequency-dependence, but does not prevent maximum principle violation in the photon intensity, eventually leading to material overheating. The Boltzman transport correction guarantees adherence to the maximum principle formore » frequency-independent simulations, at the cost of evaluating a reduced source non-linear Boltzman equation. Finally, we present numerical evidence suggesting that the Boltzman transport correction, in its current form, significantly improves time step limitations but does not guarantee adherence to the maximum principle for frequency-dependent simulations.« less

The variation in frequency locations in Doppler ultrasound spectra for maximum blood flow velocities in narrowed vessels.

PubMed

Zhang, Yingyun; Zhang, Yufeng; Gao, Lian; Deng, Li; Hu, Xiao; Zhang, Kexin; Li, Haiyan

2017-11-01

This study assessed the variation in the frequency locations in the Doppler ultrasound spectra for the maximum blood flow velocities of in vessels with different degrees of bilaterally axisymmetric stenosis. This was done by comparing the relationship between the velocity distributions and corresponding Doppler power spectra. First, a geometric vessel model with axisymmetric stenosis was established. This made it possible to obtain the blood flow velocity distributions for different degrees of stenosis from the solutions of the Navier-Stokes equations. Then, the Doppler spectra were calculated for the entire segment of the vessel that was covered by the sound field. Finally, the maximum frequency locations for the spectra were determined based on the intersections of the maximum values chosen from the calculated blood flow velocity distributions and their corresponding spectra. The computational analysis showed that the maximum frequencies, which corresponded to the maximum blood flow velocities for different degrees of stenosis, were located at different positions along the spectral falling edges. The location for a normal (stenosis free) vessel was in the middle of the falling edge. For vessels with increasing degrees of stenosis, this location shifted approximately linearly downward along the falling edge. For 40% stenosis, the location reached a position at the falling edge of 0.32. Results obtained using the Field II simulation tool demonstrated the validity of the theoretical analysis and calculations, and may help to improve the maximum velocity estimation accuracy for Doppler blood flow spectra in stenosed vessels. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

36 CFR 1193.31 - Accessibility and usability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Accessibility and usability... COMPLIANCE BOARD TELECOMMUNICATIONS ACT ACCESSIBILITY GUIDELINES Requirements for Accessibility and Usability § 1193.31 Accessibility and usability. When required by § 1193.21, telecommunications equipment and...

36 CFR 1193.31 - Accessibility and usability.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Accessibility and usability... COMPLIANCE BOARD TELECOMMUNICATIONS ACT ACCESSIBILITY GUIDELINES Requirements for Accessibility and Usability § 1193.31 Accessibility and usability. When required by § 1193.21, telecommunications equipment and...

36 CFR 1193.31 - Accessibility and usability.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Accessibility and usability... COMPLIANCE BOARD TELECOMMUNICATIONS ACT ACCESSIBILITY GUIDELINES Requirements for Accessibility and Usability § 1193.31 Accessibility and usability. When required by § 1193.21, telecommunications equipment and...

36 CFR 1193.31 - Accessibility and usability.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Accessibility and usability... COMPLIANCE BOARD TELECOMMUNICATIONS ACT ACCESSIBILITY GUIDELINES Requirements for Accessibility and Usability § 1193.31 Accessibility and usability. When required by § 1193.21, telecommunications equipment and...

Less is more: development and evaluation of an interactive e-atlas to support anatomy learning.

PubMed

Guy, Richard; Pisani, Heather R; Rich, Peter; Leahy, Cathy; Mandarano, Giovanni; Molyneux, Tom

2015-01-01

An Interactive electronic Atlas (IeA) was developed to assist first-year nursing students with interpretation of laboratory-based prosected cadaveric material. It was designed, using pedagogically sound principles, as a student-centered resource accessible to students from a wide range of learning backgrounds. It consisted of a highly simplified interactive interface limited to essential anatomical structures and was intended for use in a blended learning situation. The IeA's nine modules mirrored the body systems covered in a Nursing Biosciences course, with each module comprising a maximum of 10 pages using the same template: an image displaying a cadaveric specimen and, in most cases, a corresponding anatomical model with navigation panes (menus) on one side. Cursor movement over the image or clicking the menu highlighted the structure with a transparent overlay and revealed a succinct functional description. The atlas was complemented by a multiple-choice database of nearly 1,000 questions using IeA images. Students' perceptions of usability and utility were measured by survey (n = 115; 57% of the class) revealing mean access of 2.3 times per week during the 12-week semester and a median time of three hours of use. Ratings for usability and utility were high, with means ranging between 4.24 and 4.54 (five-point Likert scale; 5 = strongly agree). Written responses told a similar story for both usability and utility. The role of providing basic computer-assisted learning support for a large first-year class is discussed in the context of current research into student-centered resources and blended learning in human anatomy. © 2014 American Association of Anatomists.

Usability Evaluation of Electronic Health Record System around Clinical Notes Usage-An Ethnographic Study.

PubMed

Rizvi, Rubina F; Marquard, Jenna L; Hultman, Gretchen M; Adam, Terrence J; Harder, Kathleen A; Melton, Genevieve B

2017-10-01

Background A substantial gap exists between current Electronic Health Record (EHR) usability and potential optimal usability. One of the fundamental reasons for this discrepancy is poor incorporation of a User-Centered Design (UCD) approach during the Graphical User Interface (GUI) development process. Objective To evaluate usability strengths and weaknesses of two widely implemented EHR GUIs for critical clinical notes usage tasks. Methods Twelve Internal Medicine resident physicians interacting with one of the two EHR systems (System-1 at Location-A and System-2 at Location-B) were observed by two usability evaluators employing an ethnographic approach. User comments and observer findings were analyzed for two critical tasks: (1) clinical notes entry and (2) related information-seeking tasks. Data were analyzed from two standpoints: (1) usability references categorized by usability evaluators as positive, negative, or equivocal and (2) usability impact of each feature measured through a 7-point severity rating scale. Findings were also validated by user responses to a post observation questionnaire. Results For clinical notes entry, System-1 surpassed System-2 with more positive (26% vs. 12%) than negative (12% vs. 34%) usability references. Greatest impact features on EHR usability (severity score pertaining to each feature) for clinical notes entry were: autopopulation (6), screen options (5.5), communication (5), copy pasting (4.5), error prevention (4.5), edit ability (4), and dictation and transcription (3.5). Both systems performed equally well on information-seeking tasks and features with greatest impacts on EHR usability were navigation for notes (7) and others (e.g., looking for ancillary data; 5.5). Ethnographic observations were supported by follow-up questionnaire responses. Conclusion This study provides usability-specific insights to inform future, improved, EHR interface that is better aligned with UCD approach.

Relationship between Audiometric Slope and Tinnitus Pitch in Tinnitus Patients: Insights into the Mechanisms of Tinnitus Generation

PubMed Central

Schecklmann, Martin; Vielsmeier, Veronika; Steffens, Thomas; Landgrebe, Michael; Langguth, Berthold; Kleinjung, Tobias

2012-01-01

Background Different mechanisms have been proposed to be involved in tinnitus generation, among them reduced lateral inhibition and homeostatic plasticity. On a perceptual level these different mechanisms should be reflected by the relationship between the individual audiometric slope and the perceived tinnitus pitch. Whereas some studies found the tinnitus pitch corresponding to the maximum hearing loss, others stressed the relevance of the edge frequency. This study investigates the relationship between tinnitus pitch and audiometric slope in a large sample. Methodology This retrospective observational study analyzed 286 patients. The matched tinnitus pitch was compared to the frequency of maximum hearing loss and the edge of the audiogram (steepest hearing loss) by t-tests and correlation coefficients. These analyses were performed for the whole group and for sub-groups (uni- vs. bilateral (117 vs. 338 ears), pure-tone vs. narrow-band (340 vs. 115 ears), and low and high audiometric slope (114 vs. 113 ears)). Findings For the right ear, tinnitus pitch was in the same range and correlated significantly with the frequency of maximum hearing loss, but differed from and did not correlate with the edge frequency. For the left ear, similar results were found but the correlation between tinnitus pitch and maximum hearing loss did not reach significance. Sub-group analyses (bi- and unilateral, tinnitus character, slope steepness) revealed identical results except for the sub-group with high audiometric slope which revealed a higher frequency of maximum hearing loss as compared to the tinnitus pitch. Conclusion The study-results confirm a relationship between tinnitus pitch and maximum hearing loss but not to the edge frequency, suggesting that tinnitus is rather a fill-in-phenomenon resulting from homeostatic mechanisms, than the result of deficient lateral inhibition. Sub-group analyses suggest that audiometric steepness and the side of affected ear affect this relationship. Future studies should control for these potential confounding factors. PMID:22529949

The health systems' priority setting criteria for selecting health technologies: A systematic review of the current evidence.

PubMed

Mobinizadeh, Mohammadreza; Raeissi, Pouran; Nasiripour, Amir Ashkan; Olyaeemanesh, Alireza; Tabibi, Seyed Jamaleddin

2016-01-01

In the recent years, using health technologies to diagnose and treat diseases has had a considerable and accelerated growth. The proper use of these technologies may considerably help in the diagnosis and treatment of different diseases. On the other hand, unlimited and unrestricted entry of these technologies may result in induced demand by service providers. The aim of this study was to determine the appropriate criteria used in health technologies priority-setting models in the world. Using MESH and free text, we sought and retrieved the relevant articles from the most appropriate medical databases (the Cochrane Library, PubMed and Scopus) through three separate search strategies up to March 2015. The inclusion criteria were as follows: 1) Studies with specific criteria; 2) Articles written in English; 3) Those articles conducted in compliance with priority setting of health technologies. Data were analyzed qualitatively using a thematic synthesis technique. After screening the retrieved papers via PRISMA framework, from the 7,012 papers, 40 studies were included in the final phase. Criteria for selecting health technologies (in pre assessment and in the assessment phase) were categorized into six main themes: 1) Health outcomes; 2) Disease and target population; 3) Technology alternatives; 4) Economic aspects; 5) Evidence; 6) and other factors. "Health effects/benefits" had the maximum frequency in health outcomes (8 studies); "disease severity" had the maximum frequency in disease and target population (12 studies); "the number of alternatives" had the maximum frequency in alternatives (2 studies); "cost-effectiveness" had the maximum frequency in economic aspects (15 studies); "quality of evidence" had the maximum frequency in evidence (4 studies); and "issues concerning the health system" had the maximum frequency in other factors (10 studies). The results revealed an increase in the number of studies on health technologies priority setting around the world, and emphasized the necessity of application of a multi- criteria approach for appropriate decision making about healthcare technologies in the health systems.

Flood frequency analysis for nonstationary annual peak records in an urban drainage basin

USGS Publications Warehouse

Villarini, G.; Smith, J.A.; Serinaldi, F.; Bales, J.; Bates, P.D.; Krajewski, W.F.

2009-01-01

Flood frequency analysis in urban watersheds is complicated by nonstationarities of annual peak records associated with land use change and evolving urban stormwater infrastructure. In this study, a framework for flood frequency analysis is developed based on the Generalized Additive Models for Location, Scale and Shape parameters (GAMLSS), a tool for modeling time series under nonstationary conditions. GAMLSS is applied to annual maximum peak discharge records for Little Sugar Creek, a highly urbanized watershed which drains the urban core of Charlotte, North Carolina. It is shown that GAMLSS is able to describe the variability in the mean and variance of the annual maximum peak discharge by modeling the parameters of the selected parametric distribution as a smooth function of time via cubic splines. Flood frequency analyses for Little Sugar Creek (at a drainage area of 110 km2) show that the maximum flow with a 0.01-annual probability (corresponding to 100-year flood peak under stationary conditions) over the 83-year record has ranged from a minimum unit discharge of 2.1 m3 s- 1 km- 2 to a maximum of 5.1 m3 s- 1 km- 2. An alternative characterization can be made by examining the estimated return interval of the peak discharge that would have an annual exceedance probability of 0.01 under the assumption of stationarity (3.2 m3 s- 1 km- 2). Under nonstationary conditions, alternative definitions of return period should be adapted. Under the GAMLSS model, the return interval of an annual peak discharge of 3.2 m3 s- 1 km- 2 ranges from a maximum value of more than 5000 years in 1957 to a minimum value of almost 8 years for the present time (2007). The GAMLSS framework is also used to examine the links between population trends and flood frequency, as well as trends in annual maximum rainfall. These analyses are used to examine evolving flood frequency over future decades. ?? 2009 Elsevier Ltd.

Marketing through Usability.

ERIC Educational Resources Information Center

Morgan, Eric Lease

1999-01-01

Suggests that one of the best ways to get word-of-mouth marketing of library technology is to provide "usable" products and services. Provides an international standards definition on usability and notes that understanding usability combines an understanding of user needs/wants with an understanding of goals, functions, and limitations…

Injection locking of violet laser diodes with a 3.2 GHz offset frequency for driving Raman transitions in 43Ca+.

PubMed

Keitch, B C; Thomas, N R; Lucas, D M

2013-03-15

Two cw single-mode violet (397 nm) diode lasers are locked to a single external-cavity master diode laser by optical injection locking. A double-pass 1.6 GHz acousto-optic modulator is used to provide a 3.2 GHz offset frequency between the two slave lasers. We achieve up to 20 mW usable output in each slave beam, with as little as 25 μW of injection power at room temperature. An optical heterodyne measurement of the beat note between the two slave beams gives a linewidth of ≤10 Hz at 3.2 GHz. We also estimate the free-running linewidth of the master laser to be approximately 3 MHz by optical heterodyning with a similar device.

Sherborne Missile Fire Frequency with Unconstraint Parameters

NASA Astrophysics Data System (ADS)

Dong, Shaquan

2018-01-01

For the modeling problem of shipborne missile fire frequency, the fire frequency models with unconstant parameters were proposed, including maximum fire frequency models with unconstant parameters, and actual fire frequency models with unconstant parameters, which can be used to calculate the missile fire frequency with unconstant parameters.

Estimating usable resources from historical industry data.

USGS Publications Warehouse

Cargill, S.M.; Root, D.H.; Bailey, E.H.

1981-01-01

The commodities considered are mercury, copper and its byproducts gold and silver, and petroleum; the production and discovery data are for the US. The results indicate that the cumulative return per unit of effort, herein measured as grade of metal ores and discovery rate of recoverable petroleum, is proportional to a negative power of total effort expended, herein measured as total ore mined and total exploratory wells or footage drilled. This power relationship can be extended to some limiting point (a lower ore grade or a maximum number of exploratory wells or footage), and the apparent quantity of available remaining resource at that limit can be calculated. -from Authors

Microwave non-contact imaging of subcutaneous human body tissues

PubMed Central

Chernokalov, Alexander; Khripkov, Alexander; Cho, Jaegeol; Druchinin, Sergey

2015-01-01

A small-size microwave sensor is developed for non-contact imaging of a human body structure in 2D, enabling fitness and health monitoring using mobile devices. A method for human body tissue structure imaging is developed and experimentally validated. Subcutaneous fat tissue reconstruction depth of up to 70 mm and maximum fat thickness measurement error below 2 mm are demonstrated by measurements with a human body phantom and human subjects. Electrically small antennas are developed for integration of the microwave sensor into a mobile device. Usability of the developed microwave sensor for fitness applications, healthcare, and body weight management is demonstrated. PMID:26609415

Accurate determination of complex materials coefficients of piezoelectric resonators.

PubMed

Du, Xiao-Hong; Wang, Qing-Ming; Uchino, Kenji

2003-03-01

This paper presents a method of accurately determining the complex piezoelectric and elastic coefficients of piezoelectric ceramic resonators from the measurement of the normalized electric admittance, Y, which is electric admittance Y of piezoelectric resonator normalized by the angular frequency omega. The coefficients are derived from the measurements near three special frequency points that correspond to the maximum and the minimum normalized susceptance (B) and the maximum normalized conductance (G). The complex elastic coefficient is determined from the frequencies at these points, and the real and imaginary parts of the piezoelectric coefficient are related to the derivative of the susceptance with respect to the frequency and the asymmetry of the conductance, respectively, near the maximum conductance point. The measurements for some lead zirconate titanate (PZT) based ceramics are used as examples to demonstrate the calculation and experimental procedures and the comparisons with the standard methods.

Vocal warm-up increases phonation threshold pressure in soprano singers at high pitch.

PubMed

Motel, Tamara; Fisher, Kimberly V; Leydon, Ciara

2003-06-01

Vocal warm-up is thought to optimize singing performance. We compared effects of short-term, submaximal, vocal warm-up exercise with those of vocal rest on the soprano voice (n = 10, ages 19-21 years). Dependent variables were the minimum subglottic air pressure required for vocal fold oscillation to occur (phonation threshold pressure, Pth), and the maximum and minimum phonation fundamental frequency. Warm-up increased Pth for high pitch phonation (p = 0.033), but not for comfortable (p = 0.297) or low (p = 0.087) pitch phonation. No significant difference in the maximum phonation frequency (p = 0.193) or minimum frequency (p = 0.222) was observed. An elevated Pth at controlled high pitch, but an unchanging maximum and minimum frequency production suggests that short-term vocal exercise may increase the viscosity of the vocal fold and thus serve to stabilize the high voice.

Optimal lay-up design of variable stiffness laminated composite plates by a layer-wise optimization technique

NASA Astrophysics Data System (ADS)

Houmat, A.

2018-02-01

The optimal lay-up design for the maximum fundamental frequency of variable stiffness laminated composite plates is investigated using a layer-wise optimization technique. The design variables are two fibre orientation angles per ply. Thin plate theory is used in conjunction with a p-element to calculate the fundamental frequencies of symmetrically and antisymmetrically laminated composite plates. Comparisons with existing optimal solutions for constant stiffness symmetrically laminated composite plates show excellent agreement. It is observed that the maximum fundamental frequency can be increased considerably using variable stiffness design as compared to constant stiffness design. In addition, optimal lay-ups for the maximum fundamental frequency of variable stiffness symmetrically and antisymmetrically laminated composite plates with different aspect ratios and various combinations of free, simply supported and clamped edge conditions are presented. These should prove a useful benchmark for optimal lay-ups of variable stiffness laminated composite plates.

Defining Usability: How Library Practice Differs from Published Research

ERIC Educational Resources Information Center

Chen, Yu-Hui; Germain, Carol Anne; Rorissa, Abebe

2011-01-01

Library/information science professionals need a clearly articulated definition of usability/Web usability to implement intuitive websites. In this study, the authors analyzed usability definitions provided by the ARL library professionals and those found in the library/information science and computer science-information systems literature.…

48 CFR 552.270-20 - Payment.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., usable square footage delivered will be confirmed by either: (1) The Government's measurement of plans... of usable square footage stated in the lease. (c) If the amount of usable square footage delivered is... space delivered and the annual rental will be adjusted as follows: Usable square feet (USF) not...

An evaluation of patients' experienced usability of a diabetes mHealth system using a multi-method approach.

PubMed

Georgsson, Mattias; Staggers, Nancy

2016-02-01

mHealth systems are becoming more common to aid patients in their diabetes self-management, but recent studies indicate a need for thorough evaluation of patients' experienced usability. Current evaluations lack a multi-method design for data collection and structured methods for data analyses. The purpose of this study was to provide a feasibility test of a multi-method approach for both data collection and data analyses for patients' experienced usability of a mHealth system for diabetes type 2 self-management. A random sample of 10 users was selected from a larger clinical trial. Data collection methods included user testing with eight representative tasks and Think Aloud protocol, a semi-structured interview and a questionnaire on patients' experiences using the system. The Framework Analysis (FA) method and Usability Problem Taxonomy (UPT) were used to structure, code and analyze the results. A usability severity rating was assigned after classification. The combined methods resulted in a total of 117 problems condensed into 19 usability issues with an average severity rating of 2.47 or serious. The usability test detected 50% of the initial usability problems, followed by the post-interview at 29%. The usability test found 18 of 19 consolidated usability problems while the questionnaire uncovered one unique issue. Patients experienced most usability problems (8) in the Glucose Readings View when performing complex tasks such as adding, deleting, and exporting glucose measurements. The severity ratings were the highest for the Glucose Diary View, Glucose Readings View, and Blood Pressure View with an average severity rating of 3 (serious). Most of the issues were classified under the artifact component of the UPT and primary categories of Visualness (7) and Manipulation (6). In the UPT task component, most issues were in the primary category Task-mapping (12). Multiple data collection methods yielded a more comprehensive set of usability issues. Usability testing uncovered the largest volume of usability issues, followed by interviewing and then the questionnaire. The interview did not surface any unique consolidated usability issues while the questionnaire surfaced one. The FA and UPT were valuable in structuring and classifying problems. The resulting descriptions serve as a communication tool in problem solving and programming. We recommend the usage of multiple methods in data collection and employing the FA and UPT in data analyses for future usability testing. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

The value of Retrospective and Concurrent Think Aloud in formative usability testing of a physician data query tool.

PubMed

Peute, Linda W P; de Keizer, Nicolette F; Jaspers, Monique W M

2015-06-01

To compare the performance of the Concurrent (CTA) and Retrospective (RTA) Think Aloud method and to assess their value in a formative usability evaluation of an Intensive Care Registry-physician data query tool designed to support ICU quality improvement processes. Sixteen representative intensive care physicians participated in the usability evaluation study. Subjects were allocated to either the CTA or RTA method by a matched randomized design. Each subject performed six usability-testing tasks of varying complexity in the query tool in a real-working context. Methods were compared with regard to number and type of problems detected. Verbal protocols of CTA and RTA were analyzed in depth to assess differences in verbal output. Standardized measures were applied to assess thoroughness in usability problem detection weighted per problem severity level and method overall effectiveness in detecting usability problems with regard to the time subjects spent per method. The usability evaluation of the data query tool revealed a total of 43 unique usability problems that the intensive care physicians encountered. CTA detected unique usability problems with regard to graphics/symbols, navigation issues, error messages, and the organization of information on the query tool's screens. RTA detected unique issues concerning system match with subjects' language and applied terminology. The in-depth verbal protocol analysis of CTA provided information on intensive care physicians' query design strategies. Overall, CTA performed significantly better than RTA in detecting usability problems. CTA usability problem detection effectiveness was 0.80 vs. 0.62 (p<0.05) respectively, with an average difference of 42% less time spent per subject compared to RTA. In addition, CTA was more thorough in detecting usability problems of a moderate (0.85 vs. 0.7) and severe nature (0.71 vs. 0.57). In this study, the CTA is more effective in usability-problem detection and provided clarification of intensive care physician query design strategies to inform redesign of the query tool. However, CTA does not outperform RTA. The RTA additionally elucidated unique usability problems and new user requirements. Based on the results of this study, we recommend the use of CTA in formative usability evaluation studies of health information technology. However, we recommend further research on the application of RTA in usability studies with regard to user expertise and experience when focusing on user profile customized (re)design. Copyright © 2015 Elsevier Inc. All rights reserved.

Advancing Usability Evaluation through Human Reliability Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ronald L. Boring; David I. Gertman

2005-07-01

This paper introduces a novel augmentation to the current heuristic usability evaluation methodology. The SPAR-H human reliability analysis method was developed for categorizing human performance in nuclear power plants. Despite the specialized use of SPAR-H for safety critical scenarios, the method also holds promise for use in commercial off-the-shelf software usability evaluations. The SPAR-H method shares task analysis underpinnings with human-computer interaction, and it can be easily adapted to incorporate usability heuristics as performance shaping factors. By assigning probabilistic modifiers to heuristics, it is possible to arrive at the usability error probability (UEP). This UEP is not a literal probabilitymore » of error but nonetheless provides a quantitative basis to heuristic evaluation. When combined with a consequence matrix for usability errors, this method affords ready prioritization of usability issues.« less

Promoting Usability in Organizations with a New Health Usability Model: Implications for Nursing Informatics

PubMed Central

Staggers, Nancy; Rodney, Melanie

2012-01-01

Usability issues with products such as Electronic Health Records (EHRs) are of global interest to nursing informaticists. Although improvements in patient safety, clinical productivity and effectiveness are possible when usability principles and practices are in place, most organizations do not embrace usability. This paper presents a new Health Usability Maturity Model consisting of 5 phases: unrecognized, preliminary, implemented, integrated and strategic. Within each level various aspects are discussed including focus on users, management, education, resources, processes and infrastructure. Nurse informaticists may use this new model as a guide for assessing their organization’s level of usability and transitioning to the next level. Using tactics outlined here, nurse informaticists may also serve as catalysts for change and lead efforts to improve the user experience in organizations across industry, academe and healthcare settings. PMID:24199128

Systematic Review Protocol to Assess the Effectiveness of Usability Questionnaires in mHealth App Studies

PubMed Central

Bao, Jie; Parmanto, Bambang

2017-01-01

Background Usability questionnaires have a wide use in mobile health (mHealth) app usability studies. However, no systematic review has been conducted for assessing the effectiveness of these questionnaires. Objective This paper describes a protocol for conducting a systematic review of published questionnaire-based mHealth app usability studies. Methods In this systematic review, we will select recently published (2008-2017) articles from peer-reviewed journals and conferences that describe mHealth app usability studies and implement at least one usability questionnaire. The search strategy will include terms such as “mobile app” and “usability.” Multiple databases such as PubMed, CINAHL, IEEE Xplore, ACM Digital Library, and INSPEC will be searched. There will be 2 independent reviewers in charge of screening titles and abstracts as well as determining those articles that should be included for a full-text review. The third reviewer will act as a mediator between the other 2 reviewers. Moreover, a data extraction form will be created and used during the full article data analysis. Notably, the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines will be followed in reporting this protocol. Results A preliminary search produced 1271 articles, 40 of which are duplicate records. The inclusion-exclusion criteria are being strictly followed in performing the ongoing study selection. Conclusions Usability questionnaires are an important tool in mHealth app usability studies. This review will summarize the usability questionnaires used in published research articles while assessing the efficacy of these questionnaires in determining the usability of mHealth apps. PMID:28765101

Investigation of the Usability of Computerized Critical Care Information Systems in Germany.

PubMed

von Dincklage, Falk; Suchodolski, Klaudiusz; Lichtner, Gregor; Friesdorf, Wolfgang; Podtschaske, Beatrice; Ragaller, Maximilian

2017-01-01

The term "usability" describes how effectively, efficiently, and with what level of user satisfaction an information system can be used to accomplish specific goals. Computerized critical care information systems (CCISs) with high usability increase quality of care and staff satisfaction, while reducing medication errors. Conversely, systems lacking usability can interrupt clinical workflow, facilitate errors, and increase charting time. The aim of this study was to investigate and compare usability across CCIS currently used in Germany. In this study, German intensive care unit (ICU) nurses and physicians completed a specialized, previously validated, web-based questionnaire. The questionnaire assessed CCIS usability based on three rating models: an overall rating of the systems, a model rating technical usability, and a model rating task-specific usability. We analyzed results from 535 survey participants and compared eight different CCIS commonly used in Germany. Our results showed that usability strongly differs across the compared systems. The system ICUData had the best overall rating and technical usability, followed by the platforms ICM and MetaVision. The same three systems performed best in the rating of task-specific usability without significant differences between each other. Across all systems, overall ratings were more dependent on ease-of-use aspects than on aspects of utility/functionality, and the general scope of the functions offered was rated better than how well the functions are realized. Our results suggest that manufacturers should shift some of their effort away from the development of new features and focus more on improving the ease-of-use and quality of existing features.

Evaluation of Home Health Care Devices: Remote Usability Assessment.

PubMed

Kortum, Philip; Peres, S Camille

2015-06-05

An increasing amount of health care is now performed in a home setting, away from the hospital. While there is growing anecdotal evidence about the difficulty patients and caregivers have using increasingly complex health care devices in the home, there has been little systematic scientific study to quantify the global nature of home health care device usability in the field. Research has tended to focus on a handful of devices, making it difficult to gain a broad view of the usability of home-care devices in general. The objective of this paper is to describe a remote usability assessment method using the System Usability Scale (SUS), and to report on the usability of a broad range of health care devices using this metric. A total of 271 participants selected and rated up to 10 home health care devices of their choice using the SUS, which scores usability from 0 (unusable) to 100 (highly usable). Participants rated a total of 455 devices in their own home without an experimenter present. Usability scores ranged from 98 (oxygen masks) to 59 (home hormone test kits). An analysis conducted on devices that had at least 10 ratings showed that the effect of device on SUS scores was significant (P<.001), and that the usability of these devices was on the low end when compared with other commonly used items in the home, such as microwave ovens and telephones. A large database of usability scores for home health care devices collected using this remote methodology would be beneficial for physicians, patients, and their caregivers.

76 FR 8715 - Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-15

.... Title; Associated Form; and OMB Number: Electronic Health Record (EHR) Usability Survey; OMB Control... longitudinal measure of how end-users perceive the usability of the Department of Defense (DoD) suite of... usability of a system. This usability attribute describes the ease with which people can use the system to...

77 FR 25707 - Submission for OMB Review; Comment request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-01

... and OMB Number: Electronic Health Record (EHR) Usability Survey; OMB Control Number 0720-TBD. Type of... information collection is to develop a longitudinal measure of how end-users perceive the usability of the... the focus has shifted towards understanding the usability of a system. This usability attribute...

36 CFR § 1193.31 - Accessibility and usability.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Accessibility and usability. § 1193.31 Section § 1193.31 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION... and Usability § 1193.31 Accessibility and usability. When required by § 1193.21, telecommunications...

Navigator alignment using radar scan

DOEpatents

Doerry, Armin W.; Marquette, Brandeis

2016-04-05

The various technologies presented herein relate to the determination of and correction of heading error of platform. Knowledge of at least one of a maximum Doppler frequency or a minimum Doppler bandwidth pertaining to a plurality of radar echoes can be utilized to facilitate correction of the heading error. Heading error can occur as a result of component drift. In an ideal situation, a boresight direction of an antenna or the front of an aircraft will have associated therewith at least one of a maximum Doppler frequency or a minimum Doppler bandwidth. As the boresight direction of the antenna strays from a direction of travel at least one of the maximum Doppler frequency or a minimum Doppler bandwidth will shift away, either left or right, from the ideal situation.

Maximum reflectance and transmittance of films coated with gapped graphene in the context of the Dirac model

NASA Astrophysics Data System (ADS)

Klimchitskaya, G. L.; Mostepanenko, V. M.

2018-06-01

The analytic expressions for the maximum and minimum reflectances of optical films coated with gapped graphene are derived in the application region of the Dirac model taking into account multiple reflections. The respective film thicknesses are also found. In so doing the film material is described by the frequency-dependent index of refraction and graphene by the polarization tensor defined along the real frequency axis. The developed formalism is illustrated by an example of the graphene-coated film made of amorphous silica. Numerical computations of the maximum and minimum reflectances and respective film thicknesses are performed at room temperature in two frequency regions belonging to the near-infrared and far-infrared domains. It is shown that in the far-infrared domain the graphene coating has a profound effect on the values of maximum reflectance and respective film thickness leading to a relative increase in their values by up to 65% and 50%, respectively. The maximum transmittance of a graphene-coated film of appropriately chosen thickness is shown to exceed 90%. Possible applications of the obtained results are discussed.

Comparison of water and air charged transducer catheter pressures in the evaluation of cystometrogram and voiding pressure studies.

PubMed

McKinney, Timothy B; Babin, Elizabeth A; Ciolfi, Veronica; McKinney, Cynthia R; Shah, Nima

2018-04-01

Air-charged (AC) and water-perfused (WP) catheters have been evaluated for differences in measuring pressures for voiding dysfunction. Typically, a two-catheter system was used. We believe that simultaneous pressure measurements with AC and WP in a single catheter will provide analogous pressures for coughs, Valsalvas, and maximum pressures in voiding pressure studies (VPS). This IRB approved prospective study included 50 women over age 21. AC dual TDOC catheters were utilized. The water-filling channel served as the bladder filler and the water pressure readings. Patients were evaluated with empty bladders and at volumes of 50-100 mL, 200 mL, and maximum capacity with cough and Valsalva maneuvers. Comparative analysis was performed on maximum stress peak pressures. At maximum bladder capacity, VPS was done and maximum voiding pressure was recorded. Comparing coughs and Valsalva maneuvers pressures, there was significant increase in variability between AC and WP measurements with less than 50 mL volume (P < 0.001). Significant correlations were observed between AC and WP measurements for coughs and Valsalvas with bladder volume over 50 mL. Visual impression showed virtually identical tracings. Cough measurements had an average difference of 0.25 cmH 2 O (±8.81) and Valsalva measurements had an average difference of 3.15 cmH 2 O (±4.72). Thirty-eight women had usable maximum voiding pressure measurements and had a strong correlation. Cystometrogram and maximum voiding pressure measurements done with either water or air charged catheters will yield similarly accurate results and are comparable. Results suggest more variability at low bladder volumes <50 mL. © 2018 Wiley Periodicals, Inc.

Usability: Human Research Program - Space Human Factors and Habitability

NASA Technical Reports Server (NTRS)

Sandor, Aniko; Holden, Kritina L.

2009-01-01

The Usability project addresses the need for research in the area of metrics and methodologies used in hardware and software usability testing in order to define quantifiable and verifiable usability requirements. A usability test is a human-in-the-loop evaluation where a participant works through a realistic set of representative tasks using the hardware/software under investigation. The purpose of this research is to define metrics and methodologies for measuring and verifying usability in the aerospace domain in accordance with FY09 focus on errors, consistency, and mobility/maneuverability. Usability metrics must be predictive of success with the interfaces, must be easy to obtain and/or calculate, and must meet the intent of current Human Systems Integration Requirements (HSIR). Methodologies must work within the constraints of the aerospace domain, be cost and time efficient, and be able to be applied without extensive specialized training.

A human reliability based usability evaluation method for safety-critical software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boring, R. L.; Tran, T. Q.; Gertman, D. I.

2006-07-01

Boring and Gertman (2005) introduced a novel method that augments heuristic usability evaluation methods with that of the human reliability analysis method of SPAR-H. By assigning probabilistic modifiers to individual heuristics, it is possible to arrive at the usability error probability (UEP). Although this UEP is not a literal probability of error, it nonetheless provides a quantitative basis to heuristic evaluation. This method allows one to seamlessly prioritize and identify usability issues (i.e., a higher UEP requires more immediate fixes). However, the original version of this method required the usability evaluator to assign priority weights to the final UEP, thusmore » allowing the priority of a usability issue to differ among usability evaluators. The purpose of this paper is to explore an alternative approach to standardize the priority weighting of the UEP in an effort to improve the method's reliability. (authors)« less

Usability Evaluation of a Web-Based Learning System

ERIC Educational Resources Information Center

Nguyen, Thao

2012-01-01

The paper proposes a contingent, learner-centred usability evaluation method and a prototype tool of such systems. This is a new usability evaluation method for web-based learning systems using a set of empirically-supported usability factors and can be done effectively with limited resources. During the evaluation process, the method allows for…

The Development of MSFC Usability Lab

NASA Technical Reports Server (NTRS)

Cheng, Yiwei; Richardson, Sally

2010-01-01

This conference poster reviews the development of the usability lab at Marshall Space Flight Center. The purpose of the lab was to integrate a fully functioning usability laboratory to provide a resource for future human factor assessments. and to implement preliminary usability testing on a MSFC website to validate the functionality of the lab.

Understanding Usability: Investigating an Integrated Design Environment and Management System

ERIC Educational Resources Information Center

Lee, Jason Chong; Wahid, Shahtab; McCrickard, D. Scott; Chewar, C. M.; Congleton, Ben

2007-01-01

Purpose: Decades of innovation in designing usable (and unusable) interfaces have resulted in a plethora of guidelines, usability methods, and other design tools. The purpose of this research is to develop ways for novice developers to effectively leverage and contribute to the large and growing body of usability knowledge and methods.…

Usability and Gratifications--Towards a Website Analysis Model.

ERIC Educational Resources Information Center

Bunz, Ulla K.

This paper discusses Web site usability issues. Specifically, it assumes that the usability of a Web site depends more on the perception of the user than on the objectively assessable usability criteria of the Web site. Two pilot studies, based on theoretical notions of uses and gratifications theory and similar theories, are presented. In the…

Integration of MSFC Usability Lab with Usability Testing

NASA Technical Reports Server (NTRS)

Cheng, Yiwei; Richardson, Sally

2010-01-01

As part of the Stage Analysis Branch, human factors engineering plays an important role in relating humans to the systems of hardware and structure designs of the new launch vehicle. While many branches are involved in the technical aspects of creating a launch vehicle, human factors connects humans to the scientific systems with the goal of improving operational performance and safety while reducing operational error and damage to the hardware. Human factors engineers use physical and computerized models to visualize possible areas for improvements to ensure human accessibility to components requiring maintenance and that the necessary maintenance activities can be accomplished with minimal risks to human and hardware. Many methods of testing are used to fulfill this goal, such as physical mockups, computerized visualization, and usability testing. In this analysis, a usability test is conducted to test how usable a website is to users who are and are not familiar with it. The testing is performed using participants and Morae software to record and analyze the results. This analysis will be a preliminary test of the usability lab in preparation for use in new spacecraft programs, NASA Enterprise, or other NASA websites. The usability lab project is divided into two parts: integration of the usability lab and a preliminary test of the usability lab.

A usability evaluation of four commercial dental computer-based patient record systems

PubMed Central

Thyvalikakath, Thankam P.; Monaco, Valerie; Thambuganipalle, Hima Bindu; Schleyer, Titus

2008-01-01

Background The usability of dental computer-based patient record (CPR) systems has not been studied, despite early evidence that poor usability is a problem for dental CPR system users at multiple levels. Methods The authors conducted formal usability tests of four dental CPR systems by using a purposive sample of four groups of five novice users. The authors measured task outcomes (correctly completed, incorrectly completed and incomplete) in each CPR system while the participants performed nine clinical documentation tasks, as well as the number of usability problems identified in each CPR system and their potential relationship to task outcomes. The authors reviewed the software application design aspects responsible for these usability problems. Results The range for correctly completed tasks was 16 to 64 percent, for incorrectly completed tasks 18 to 38 percent and for incomplete tasks 9 to 47 percent. The authors identified 286 usability problems. The main types were three unsuccessful attempts, negative affect and task incorrectly completed. They also identified six problematic interface and interaction designs that led to usability problems. Conclusion The four dental CPR systems studied have significant usability problems for novice users, resulting in a steep learning curve and potentially reduced system adoption. Clinical Implications The significant number of data entry errors raises concerns about the quality of documentation in clinical practice. PMID:19047669

Design and validation of a questionnaire to evaluate the usability of computerized critical care information systems.

PubMed

von Dincklage, Falk; Lichtner, Gregor; Suchodolski, Klaudiusz; Ragaller, Maximilian; Friesdorf, Wolfgang; Podtschaske, Beatrice

2017-08-01

The implementation of computerized critical care information systems (CCIS) can improve the quality of clinical care and staff satisfaction, but also holds risks of disrupting the workflow with consecutive negative impacts. The usability of CCIS is one of the key factors determining their benefits and weaknesses. However, no tailored instrument exists to measure the usability of such systems. Therefore, the aim of this study was to design and validate a questionnaire that measures the usability of CCIS. Following a mixed-method design approach, we developed a questionnaire comprising two evaluation models to assess the usability of CCIS: (1) the task-specific model rates the usability individually for several tasks which CCIS could support and which we derived by analyzing work processes in the ICU; (2) the characteristic-specific model rates the different aspects of the usability, as defined by the international standard "ergonomics of human-system interaction". We tested validity and reliability of the digital version of the questionnaire in a sample population. In the sample population of 535 participants both usability evaluation models showed a strong correlation with the overall rating of the system (multiple correlation coefficients ≥0.80) as well as a very high internal consistency (Cronbach's alpha ≥0.93). The novel questionnaire is a valid and reliable instrument to measure the usability of CCIS and can be used to study the influence of the usability on their implementation benefits and weaknesses.

Systematic Review Protocol to Assess the Effectiveness of Usability Questionnaires in mHealth App Studies.

PubMed

Zhou, Leming; Bao, Jie; Parmanto, Bambang

2017-08-01

Usability questionnaires have a wide use in mobile health (mHealth) app usability studies. However, no systematic review has been conducted for assessing the effectiveness of these questionnaires. This paper describes a protocol for conducting a systematic review of published questionnaire-based mHealth app usability studies. In this systematic review, we will select recently published (2008-2017) articles from peer-reviewed journals and conferences that describe mHealth app usability studies and implement at least one usability questionnaire. The search strategy will include terms such as "mobile app" and "usability." Multiple databases such as PubMed, CINAHL, IEEE Xplore, ACM Digital Library, and INSPEC will be searched. There will be 2 independent reviewers in charge of screening titles and abstracts as well as determining those articles that should be included for a full-text review. The third reviewer will act as a mediator between the other 2 reviewers. Moreover, a data extraction form will be created and used during the full article data analysis. Notably, the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines will be followed in reporting this protocol. A preliminary search produced 1271 articles, 40 of which are duplicate records. The inclusion-exclusion criteria are being strictly followed in performing the ongoing study selection. Usability questionnaires are an important tool in mHealth app usability studies. This review will summarize the usability questionnaires used in published research articles while assessing the efficacy of these questionnaires in determining the usability of mHealth apps. ©Leming Zhou, Jie Bao, Bambang Parmanto. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 01.08.2017.

Comparison of two heuristic evaluation methods for evaluating the usability of health information systems.

PubMed

Khajouei, Reza; Hajesmaeel Gohari, Sadrieh; Mirzaee, Moghaddameh

2018-04-01

In addition to following the usual Heuristic Evaluation (HE) method, the usability of health information systems can also be evaluated using a checklist. The objective of this study is to compare the performance of these two methods in identifying usability problems of health information systems. Eight evaluators independently evaluated different parts of a Medical Records Information System using two methods of HE (usual and with a checklist). The two methods were compared in terms of the number of problems identified, problem type, and the severity of identified problems. In all, 192 usability problems were identified by two methods in the Medical Records Information System. This was significantly higher than the number of usability problems identified by the checklist and usual method (148 and 92, respectively) (p < 0.0001). After removing the duplicates, the difference between the number of unique usability problems identified by the checklist method (n = 100) and usual method (n = 44) was significant (p < 0.0001). Differences between the mean severity of the real usability problems (1.83) and those identified by only one of the methods (usual = 2.05, checklist = 1.74) were significant (p = 0.001). This study revealed the potential of the two HE methods for identifying usability problems of health information systems. The results demonstrated that the checklist method had significantly better performance in terms of the number of identified usability problems; however, the performance of the usual method for identifying problems of higher severity was significantly better. Although the checklist method can be more efficient for less experienced evaluators, wherever usability is critical, the checklist should be used with caution in usability evaluations. Copyright © 2018 Elsevier Inc. All rights reserved.

A usability evaluation of a SNOMED CT based compositional interface terminology for intensive care.

PubMed

Bakhshi-Raiez, F; de Keizer, N F; Cornet, R; Dorrepaal, M; Dongelmans, D; Jaspers, M W M

2012-05-01

To evaluate the usability of a large compositional interface terminology based on SNOMED CT and the terminology application for registration of the reasons for intensive care admission in a Patient Data Management System. Observational study with user-based usability evaluations before and 3 months after the system was implemented and routinely used. Usability was defined by five aspects: effectiveness, efficiency, learnability, overall user satisfaction, and experienced usability problems. Qualitative (the Think-Aloud user testing method) and quantitative (the System Usability Scale questionnaire and Time-on-Task analyses) methods were used to examine these usability aspects. The results of the evaluation study revealed that the usability of the interface terminology fell short (SUS scores before and after implementation of 47.2 out of 100 and 37.5 respectively out of 100). The qualitative measurements revealed a high number (n=35) of distinct usability problems, leading to ineffective and inefficient registration of reasons for admission. The effectiveness and efficiency of the system did not change over time. About 14% (n=5) of the revealed usability problems were related to the terminology content based on SNOMED CT, while the remaining 86% (n=30) was related to the terminology application. The problems related to the terminology content were more severe than the problems related to the terminology application. This study provides a detailed insight into how clinicians interact with a controlled compositional terminology through a terminology application. The extensiveness, complexity of the hierarchy, and the language usage of an interface terminology are defining for its usability. Carefully crafted domain-specific subsets and a well-designed terminology application are needed to facilitate the use of a complex compositional interface terminology based on SNOMED CT. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Usability Evaluation of Laboratory Information Systems.

PubMed

Mathews, Althea; Marc, David

2017-01-01

Numerous studies have revealed widespread clinician frustration with the usability of electronic health records (EHRs) that is counterproductive to adoption of EHR systems to meet the aims of health-care reform. With poor system usability comes increased risk of negative unintended consequences. Usability issues could lead to user error and workarounds that have the potential to compromise patient safety and negatively impact the quality of care.[1] While there is ample research on EHR usability, there is little information on the usability of laboratory information systems (LISs). Yet, LISs facilitate the timely provision of a great deal of the information needed by physicians to make patient care decisions.[2] Medical and technical advances in genomics that require processing of an increased volume of complex laboratory data further underscore the importance of developing user-friendly LISs. This study aims to add to the body of knowledge on LIS usability. A survey was distributed among LIS users at hospitals across the United States. The survey consisted of the ten-item System Usability Scale (SUS). In addition, participants were asked to rate the ease of performing 24 common tasks with a LIS. Finally, respondents provided comments on what they liked and disliked about using the LIS to provide diagnostic insight into LIS perceived usability. The overall mean SUS score of 59.7 for the LIS evaluated is significantly lower than the benchmark of 68 ( P < 0.001). All LISs evaluated received mean SUS scores below 68 except for Orchard Harvest (78.7). While the years of experience using the LIS was found to be a statistically significant influence on mean SUS scores, the combined effect of years of experience and LIS used did not account for the statistically significant difference in the mean SUS score between Orchard Harvest and each of the other LISs evaluated. The results of this study indicate that overall usability of LISs is poor. Usability lags that of systems evaluated across 446 usability surveys.

Usability Evaluation of a Clinical Decision Support System for Geriatric ED Pain Treatment.

PubMed

Genes, Nicholas; Kim, Min Soon; Thum, Frederick L; Rivera, Laura; Beato, Rosemary; Song, Carolyn; Soriano, Jared; Kannry, Joseph; Baumlin, Kevin; Hwang, Ula

2016-01-01

Older adults are at risk for inadequate emergency department (ED) pain care. Unrelieved acute pain is associated with poor outcomes. Clinical decision support systems (CDSS) hold promise to improve patient care, but CDSS quality varies widely, particularly when usability evaluation is not employed. To conduct an iterative usability and redesign process of a novel geriatric abdominal pain care CDSS. We hypothesized this process would result in the creation of more usable and favorable pain care interventions. Thirteen emergency physicians familiar with the Electronic Health Record (EHR) in use at the study site were recruited. Over a 10-week period, 17 1-hour usability test sessions were conducted across 3 rounds of testing. Participants were given 3 patient scenarios and provided simulated clinical care using the EHR, while interacting with the CDSS interventions. Quantitative System Usability Scores (SUS), favorability scores and qualitative narrative feedback were collected for each session. Using a multi-step review process by an interdisciplinary team, positive and negative usability issues in effectiveness, efficiency, and satisfaction were considered, prioritized and incorporated in the iterative redesign process of the CDSS. Video analysis was used to determine the appropriateness of the CDS appearances during simulated clinical care. Over the 3 rounds of usability evaluations and subsequent redesign processes, mean SUS progressively improved from 74.8 to 81.2 to 88.9; mean favorability scores improved from 3.23 to 4.29 (1 worst, 5 best). Video analysis revealed that, in the course of the iterative redesign processes, rates of physicians' acknowledgment of CDS interventions increased, however most rates of desired actions by physicians (such as more frequent pain score updates) decreased. The iterative usability redesign process was instrumental in improving the usability of the CDSS; if implemented in practice, it could improve geriatric pain care. The usability evaluation process led to improved acknowledgement and favorability. Incorporating usability testing when designing CDSS interventions for studies may be effective to enhance clinician use.

Translation, Cross-Cultural Adaptation, and Validation of the Malay Version of the System Usability Scale Questionnaire for the Assessment of Mobile Apps.

PubMed

Mohamad Marzuki, Muhamad Fadhil; Yaacob, Nor Azwany; Yaacob, Najib Majdi

2018-05-14

A mobile app is a programmed system designed to be used by a target user on a mobile device. The usability of such a system refers not only to the extent to which product can be used to achieve the task that it was designed for, but also its effectiveness and efficiency, as well as user satisfaction. The System Usability Scale is one of the most commonly used questionnaires used to assess the usability of a system. The original 10-item version of System Usability Scale was developed in English and thus needs to be adapted into local languages to assess the usability of a mobile apps developed in other languages. The aim of this study is to translate and validate (with cross-cultural adaptation) the English System Usability Scale questionnaire into Malay, the main language spoken in Malaysia. The development of a translated version will allow the usability of mobile apps to be assessed in Malay. Forward and backward translation of the questionnaire was conducted by groups of Malay native speakers who spoke English as their second language. The final version was obtained after reconciliation and cross-cultural adaptation. The content of the Malay System Usability Scale questionnaire for mobile apps was validated by 10 experts in mobile app development. The efficacy of the questionnaire was further probed by testing the face validity on 10 mobile phone users, followed by reliability testing involving 54 mobile phone users. The content validity index was determined to be 0.91, indicating good relevancy of the 10 items used to assess the usability of a mobile app. Calculation of the face validity index resulted in a value of 0.94, therefore indicating that the questionnaire was easily understood by the users. Reliability testing showed a Cronbach alpha value of .85 (95% CI 0.79-0.91) indicating that the translated System Usability Scale questionnaire is a reliable tool for the assessment of usability of a mobile app. The Malay System Usability Scale questionnaire is a valid and reliable tool to assess the usability of mobile app in Malaysia. ©Muhamad Fadhil Mohamad Marzuki, Nor Azwany Yaacob, Najib Majdi Yaacob. Originally published in JMIR Human Factors (http://humanfactors.jmir.org), 14.05.2018.

Does the use of structured reporting improve usability? A comparative evaluation of the usability of two approaches for findings reporting in a large-scale telecardiology context.

PubMed

Lacerda, Thaisa Cardoso; von Wangenheim, Christiane Gresse; von Wangenheim, Aldo; Giuliano, Isabela

2014-12-01

One of the main reasons that leads to a low adoption rate of telemedicine systems is poor usability. An aspect that influences usability during the reporting of findings is the input mode, e.g., if a free-text (FT) or a structured report (SR) interface is employed. The objective of our study is to compare the usability of FT and ST telemedicine systems, specifically in terms of user satisfaction, efficiency and general usability. We comparatively evaluate the usability of these two input modes in a telecardiology system for issuing electrocardiography reports in the context of a statewide telemedicine system in Brazil with more than 350.000 performed tele-electrocardiography examinations. We adopted a multiple method research strategy, applying three different kinds of usability evaluations: user satisfaction was evaluated through interviews with seven medical professionals using the System Usability Scale (SUS) questionnaire and specific questions related to adequacy and user experience. Efficiency was evaluated by estimating execution time using the Keystroke-Level Model (KLM). General usability was assessed based on the conformity of the systems to a set of e-health specific usability heuristics. The results of this comparison provide a first indication that a structured report (SR) input mode for such a system is more satisfactory and efficient with a larger conformity to usability heuristics than free-text (FT) input. User satisfaction using the SUS questionnaire has been scored in average with 58.8 and 77.5 points for the FT and SR system, respectively, which means that the SR system was rated 18.65 points higher than the FT system. In terms of efficiency, the completion of a findings report using the SR mode is estimated to take 8.5s, 3.74 times faster than using the FT system (31.8s). The SR system also demonstrated less violations to usability heuristics (8 points) in comparison to 14 points observed in the FT system. These results provide a first indication that the usage of structured reporting as an input mode in telecardiology systems may enhance usability. This also seems to confirm the advantages of the usage of structured reporting, as already described in the literature for other areas such as teleradiology. Copyright © 2014 Elsevier Inc. All rights reserved.

The quality of information on the Internet on orthodontic retainer wear: a cross-sectional study.

PubMed

Doğramacı, Esma J; Rossi-Fedele, Giampiero

2016-03-01

The objectives of this study were to assess the accessibility, usability, reliability and quality of information on the Internet written for the lay public about orthodontic retainers, and to elucidate the different retention protocols encouraged. A cross-sectional, observational study. Online, using a computer connected to the Internet in Australia. Two search terms; 'orthodontic retainer' and 'how long should someone wear a retainer after their braces are removed?' were entered alternatively into five search engines. Twenty results for each search term per search engine that fulfilled the inclusion criteria were evaluated in terms of accessibility, usability, reliability and quality of information using the LIDA and DISCERN instruments, ensuring there were no internal or cross-search engine duplicates. Any information about frequency and duration of retainer wear was also collected. Two hundred different websites were identified and assessed. The median overall LIDA score was 72%, corresponding to a moderate quality level. The median total DISCERN score was 47%. Twenty-two websites recommended patients adhere to the specific protocol prescribed to them by their practitioner. There were 45 (22.5%) and 28 (14%) websites advising indefinite use of removable and bonded retainers respectively. Information about retainers on the Internet is easily accessible and usable, though the quality of the content is generally of a moderate level. However, the information is not always accurate and reliable. Both full-time and part-time wear of removable retainers was suggested over greatly varying time periods. Indefinite wear of removable and bonded retainers was also advocated.

Adaptive Gain-based Stable Power Smoothing of a DFIG

DOE PAGES

Muljadi, Eduard; Lee, Hyewon; Hwang, Min; ...

2017-11-01

In a power system that has a high wind penetration, the output power fluctuation of a large-scale wind turbine generator (WTG) caused by the varying wind speed increases the maximum frequency deviation, which is an important metric to assess the quality of electricity, because of the reduced system inertia. This paper proposes a stable power-smoothing scheme of a doubly-fed induction generator (DFIG) that can suppress the maximum frequency deviation, particularly for a power system with a high wind penetration. To do this, the proposed scheme employs an additional control loop relying on the system frequency deviation that operates in combinationmore » with the maximum power point tracking control loop. To improve the power-smoothing capability while guaranteeing the stable operation of a DFIG, the gain of the additional loop is modified with the rotor speed and frequency deviation. The gain is set to be high if the rotor speed and/or frequency deviation is large. Here, the simulation results based on the IEEE 14-bus system demonstrate that the proposed scheme significantly lessens the output power fluctuation of a WTG under various scenarios by modifying the gain with the rotor speed and frequency deviation, and thereby it can regulate the frequency deviation within a narrow range.« less

Adaptive Gain-based Stable Power Smoothing of a DFIG

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muljadi, Eduard; Lee, Hyewon; Hwang, Min

In a power system that has a high wind penetration, the output power fluctuation of a large-scale wind turbine generator (WTG) caused by the varying wind speed increases the maximum frequency deviation, which is an important metric to assess the quality of electricity, because of the reduced system inertia. This paper proposes a stable power-smoothing scheme of a doubly-fed induction generator (DFIG) that can suppress the maximum frequency deviation, particularly for a power system with a high wind penetration. To do this, the proposed scheme employs an additional control loop relying on the system frequency deviation that operates in combinationmore » with the maximum power point tracking control loop. To improve the power-smoothing capability while guaranteeing the stable operation of a DFIG, the gain of the additional loop is modified with the rotor speed and frequency deviation. The gain is set to be high if the rotor speed and/or frequency deviation is large. Here, the simulation results based on the IEEE 14-bus system demonstrate that the proposed scheme significantly lessens the output power fluctuation of a WTG under various scenarios by modifying the gain with the rotor speed and frequency deviation, and thereby it can regulate the frequency deviation within a narrow range.« less

System impairment compensation in coherent optical communications by using a bio-inspired detector based on artificial neural network and genetic algorithm

NASA Astrophysics Data System (ADS)

Wang, Danshi; Zhang, Min; Li, Ze; Song, Chuang; Fu, Meixia; Li, Jin; Chen, Xue

2017-09-01

A bio-inspired detector based on the artificial neural network (ANN) and genetic algorithm is proposed in the context of a coherent optical transmission system. The ANN is designed to mitigate 16-quadrature amplitude modulation system impairments, including linear impairment: Gaussian white noise, laser phase noise, in-phase/quadrature component imbalance, and nonlinear impairment: nonlinear phase. Without prior information or heuristic assumptions, the ANN, functioning as a machine learning algorithm, can learn and capture the characteristics of impairments from observed data. Numerical simulations were performed, and dispersion-shifted, dispersion-managed, and dispersion-unmanaged fiber links were investigated. The launch power dynamic range and maximum transmission distance for the bio-inspired method were 2.7 dBm and 240 km greater, respectively, than those of the maximum likelihood estimation algorithm. Moreover, the linewidth tolerance of the bio-inspired technique was 170 kHz greater than that of the k-means method, demonstrating its usability for digital signal processing in coherent systems.

Spectral Entropy Based Neuronal Network Synchronization Analysis Based on Microelectrode Array Measurements

PubMed Central

Kapucu, Fikret E.; Välkki, Inkeri; Mikkonen, Jarno E.; Leone, Chiara; Lenk, Kerstin; Tanskanen, Jarno M. A.; Hyttinen, Jari A. K.

2016-01-01

Synchrony and asynchrony are essential aspects of the functioning of interconnected neuronal cells and networks. New information on neuronal synchronization can be expected to aid in understanding these systems. Synchronization provides insight in the functional connectivity and the spatial distribution of the information processing in the networks. Synchronization is generally studied with time domain analysis of neuronal events, or using direct frequency spectrum analysis, e.g., in specific frequency bands. However, these methods have their pitfalls. Thus, we have previously proposed a method to analyze temporal changes in the complexity of the frequency of signals originating from different network regions. The method is based on the correlation of time varying spectral entropies (SEs). SE assesses the regularity, or complexity, of a time series by quantifying the uniformity of the frequency spectrum distribution. It has been previously employed, e.g., in electroencephalogram analysis. Here, we revisit our correlated spectral entropy method (CorSE), providing evidence of its justification, usability, and benefits. Here, CorSE is assessed with simulations and in vitro microelectrode array (MEA) data. CorSE is first demonstrated with a specifically tailored toy simulation to illustrate how it can identify synchronized populations. To provide a form of validation, the method was tested with simulated data from integrate-and-fire model based computational neuronal networks. To demonstrate the analysis of real data, CorSE was applied on in vitro MEA data measured from rat cortical cell cultures, and the results were compared with three known event based synchronization measures. Finally, we show the usability by tracking the development of networks in dissociated mouse cortical cell cultures. The results show that temporal correlations in frequency spectrum distributions reflect the network relations of neuronal populations. In the simulated data, CorSE unraveled the synchronizations. With the real in vitro MEA data, CorSE produced biologically plausible results. Since CorSE analyses continuous data, it is not affected by possibly poor spike or other event detection quality. We conclude that CorSE can reveal neuronal network synchronization based on in vitro MEA field potential measurements. CorSE is expected to be equally applicable also in the analysis of corresponding in vivo and ex vivo data analysis. PMID:27803660

Breaking through the bandwidth barrier in distributed fiber vibration sensing by sub-Nyquist randomized sampling

NASA Astrophysics Data System (ADS)

Zhang, Jingdong; Zhu, Tao; Zheng, Hua; Kuang, Yang; Liu, Min; Huang, Wei

2017-04-01

The round trip time of the light pulse limits the maximum detectable frequency response range of vibration in phase-sensitive optical time domain reflectometry (φ-OTDR). We propose a method to break the frequency response range restriction of φ-OTDR system by modulating the light pulse interval randomly which enables a random sampling for every vibration point in a long sensing fiber. This sub-Nyquist randomized sampling method is suits for detecting sparse-wideband- frequency vibration signals. Up to MHz resonance vibration signal with over dozens of frequency components and 1.153MHz single frequency vibration signal are clearly identified for a sensing range of 9.6km with 10kHz maximum sampling rate.

Dynamic modelling and experimental study of asymmetric optothermal microactuator

NASA Astrophysics Data System (ADS)

Wang, Shuying; Chun, Qin; You, Qingyang; Wang, Yingda; Zhang, Haijun

2017-01-01

This paper reports the dynamic modelling and experimental study of an asymmetric optothermal microactuator (OTMA). According to the principle of thermal flux, a theoretical model for instantaneous temperature distribution of an expansion arm is established and the expression of expansion increment is derived. Dynamic expansion properties of the arm under laser pulse irradiation are theoretically analyzed indicating that both of the maximum expansion and expansion amplitude decrease with the pulse frequency increasing. Experiments have been further carried out on an OTMA fabricated by using an excimer laser micromachining system. It is shown that the OTMA deflects periodically with the same frequency of laser pulse irradiation. Experimental results also prove that both OTMA's maximum deflection and deflection amplitude (related to maximum expansion and expansion amplitude of the arm) decrease as frequency increases, matching with the theoretical model quite well. Even though the OTMA's deflection decrease at higher frequency, it is still capable of generating 8.2 μm maximum deflection and 4.2 μm deflection amplitude under 17 Hz/2 mW laser pulse irradiation. This work improves the potential applications of optothermal microactuators in micro-opto-electro-mechanical system (MOEMS) and micro/nano-technology fields.

Improving the Usability of the User Interface for a Digital Textbook Platform for Elementary-School Students

ERIC Educational Resources Information Center

Lim, Cheolil; Song, Hae-Deok; Lee, Yekyung

2012-01-01

Usability is critical to the development of a user-friendly digital textbook platform interface, yet thorough research on interface development based on usability principles is in short supply. This study addresses that need by looking at usability attributes and corresponding design elements from a learning perspective. The researchers used a…

Using Cluster Analysis to Extend Usability Testing to Instructional Content. CRESST Report 816

ERIC Educational Resources Information Center

Kerr, Deirdre S.; Chung, Gregory K. W. K.

2012-01-01

Commercial video games undergo usability studies to determine the degree to which the player is able to learn, control, and understand the game. Usability studies allow game designers to improve their games before they are released to the public. If usability studies could be expanded to include information about the presentation of the…

Usability Testing of a Multimedia e-Learning Resource for Electrolyte and Acid-Base Disorders

ERIC Educational Resources Information Center

Davids, Mogamat Razeen; Chikte, Usuf; Grimmer-Somers, Karen; Halperin, Mitchell L.

2014-01-01

The usability of computer interfaces may have a major influence on learning. Design approaches that optimize usability are commonplace in the software development industry but are seldom used in the development of e-learning resources, especially in medical education. We conducted a usability evaluation of a multimedia resource for teaching…

Advocating for Greater Usability in Clinical Technologies: The Role of the Practicing Nurse.

PubMed

Lopez, Karen Dunn; Fahey, Linda

2018-06-01

Health care, especially ICUs, rely on multiple types of technology to promote the best patient outcomes. Unfortunately, too often these technologies are poorly designed, causing errors, additional workload, and unnecessary frustration. The purpose of this article is to (1) empower nurses with the needed usability and usability testing vocabulary to identify and articulate clinical technology usability problems and (2) provide ideas on ways nurses can advocate to have an impact on positive change related to technology usability within a health care organization. Copyright © 2018 Elsevier Inc. All rights reserved.

Development of a Video Coding Scheme for Analyzing the Usability and Usefulness of Health Information Systems.

PubMed

Kushniruk, Andre W; Borycki, Elizabeth M

2015-01-01

Usability has been identified as a key issue in health informatics. Worldwide numerous projects have been carried out in an attempt to increase and optimize health system usability. Usability testing, involving observing end users interacting with systems, has been widely applied and numerous publications have appeared describing such studies. However, to date, fewer works have been published describing methodological approaches to analyzing the rich data stream that results from usability testing. This includes analysis of video, audio and screen recordings. In this paper we describe our work in the development and application of a coding scheme for analyzing the usability of health information systems. The phases involved in such analyses are described.

Numerical and experimental study of actuator performance on piezoelectric microelectromechanical inkjet print head.

PubMed

Van So, Pham; Jun, Hyun Woo; Lee, Jaichan

2013-12-01

We have investigated the actuator performance of a piezoelectrically actuated inkjet print head via the numerical and experimental analysis. The actuator consisting of multi-layer membranes, such as piezoelectric, elastic and other buffer layers, and ink chamber was fabricated by MEMS processing. The maximum displacement of the actuator membrane obtained in the experiment is explained by numerical analysis. A simulation of the actuator performance with fluidic damping shows that the resonant frequency of the membrane in liquid is reduced from its resonant frequency in air by a factor of three, which was also verified in the experiment. These simulation and experimental studies demonstrate how much "dynamic force," in terms of a membrane's maximum displacement, maximum force and driving frequency, can be produced by an actuator membrane interacting with fluid.

SOI MESFETs on high-resistivity, trap-rich substrates

NASA Astrophysics Data System (ADS)

Mehr, Payam; Zhang, Xiong; Lepkowski, William; Li, Chaojiang; Thornton, Trevor J.

2018-04-01

The DC and RF characteristics of metal-semiconductor field-effect-transistors (MESFETs) on conventional CMOS silicon-on-insulator (SOI) substrates are compared to nominally identical devices on high-resistivity, trap-rich SOI substrates. While the DC transfer characteristics are statistically identical on either substrate, the maximum available gain at GHz frequencies is enhanced by ∼2 dB when using the trap-rich substrates, with maximum operating frequencies, fmax, that are approximately 5-10% higher. The increased fmax is explained by the reduced substrate conduction at GHz frequencies using a lumped-element, small-signal model.

Biofilm development in fixed bed biofilm reactors: experiments and simple models for engineering design purposes.

PubMed

Szilágyi, N; Kovács, R; Kenyeres, I; Csikor, Zs

2013-01-01

Biofilm development in a fixed bed biofilm reactor system performing municipal wastewater treatment was monitored aiming at accumulating colonization and maximum biofilm mass data usable in engineering practice for process design purposes. Initially a 6 month experimental period was selected for investigations where the biofilm formation and the performance of the reactors were monitored. The results were analyzed by two methods: for simple, steady-state process design purposes the maximum biofilm mass on carriers versus influent load and a time constant of the biofilm growth were determined, whereas for design approaches using dynamic models a simple biofilm mass prediction model including attachment and detachment mechanisms was selected and fitted to the experimental data. According to a detailed statistical analysis, the collected data have not allowed us to determine both the time constant of biofilm growth and the maximum biofilm mass on carriers at the same time. The observed maximum biofilm mass could be determined with a reasonable error and ranged between 438 gTS/m(2) carrier surface and 843 gTS/m(2), depending on influent load, and hydrodynamic conditions. The parallel analysis of the attachment-detachment model showed that the experimental data set allowed us to determine the attachment rate coefficient which was in the range of 0.05-0.4 m d(-1) depending on influent load and hydrodynamic conditions.

Definition of SMOS Level 3 Land Products for the Villafranca del Castillo Data Processing Centre (CP34)

NASA Astrophysics Data System (ADS)

Lopez-Baeza, E.; Monsoriu Torres, A.; Font, J.; Alonso, O.

2009-04-01

The ESA SMOS (Soil Moisture and Ocean Salinity) Mission is planned to be launched in July 2009. The satellite will measure soil moisture over the continents and surface salinity of the oceans at resolutions that are sufficient for climatological-type studies. This paper describes the procedure to be used at the Spanish SMOS Level 3 and 4 Data Processing Centre (CP34) to generate Soil Moisture and other Land Surface Product maps from SMOS Level 2 data. This procedure can be used to map Soil Moisture, Vegetation Water Content and Soil Dielectric Constant data into different pre-defined spatial grids with fixed temporal frequency. The L3 standard Land Surface Products to be generated at CP34 are: Soil Moisture products: maximum spatial resolution with no spatial averaging, temporal averaging of 3 days, daily generation maximum spatial resolution with no spatial averaging, temporal averaging of 10 days, generation frequency of once every 10 days. b': maximum spatial resolution with no spatial averaging, temporal averaging of monthly decades (1st to 10th of the month, 11th to 20th of the month, 21st to last day of the month), generation frequency of once every decade monthly average, temporal averaging from L3 decade averages, monthly generation Seasonal average, temporal averaging from L3 monthly averages, seasonally generation yearly average, temporal averaging from L3 monthly averages, yearly generation Vegetation Water Content products: maximum spatial resolution with no spatial averaging, temporal averaging of 10 days, generation frequency of once every 10 days. a': maximum spatial resolution with no spatial averaging, temporal averaging of monthly decades (1st to 10th of the month, 11th to 20th of the month, 21st to last day of the month) using simple averaging method over the L2 products in ISEA grid, generation frequency of once every decade monthly average, temporal averaging from L3 decade averages, monthly generation seasonal average, temporal averaging from L3 monthly averages, seasonally generation yearly average, temporal averaging from L3 monthly averages, yearly generation Dielectric Constant products: (the dielectric constant products are delivered together with soil moisture products, with the same averaging periods and generation frequency): maximum spatial resolution with no spatial averaging, temporal averaging of 3 days, daily generation maximum spatial resolution with no spatial averaging, temporal averaging of 10 days, generation frequency of once every 10 days. b': maximum spatial resolution with no spatial averaging, temporal averaging of monthly decades (1st to 10th of the month, 11th to 20th of the month, 21st to last day of the month), generation frequency of once every decade monthly average, temporal averaging from L3 decade averages, monthly generation seasonal average, temporal averaging from L3 monthly averages, seasonally generation yearly average, temporal averaging from L3 monthly averages, yearly generation.

Usability in product development practice; an exploratory case study comparing four markets.

PubMed

van Kuijk, Jasper; van Driel, Liesbeth; van Eijk, Daan

2015-03-01

This study explored how usability was dealt with in four product development organizations active in different sectors: high-end automotive, professional printers and copiers, office coffee makers and fast moving consumer goods. The primary differentiators of the selected cases were whether they were targeting businesses or consumers and the degree of product complexity. Interviews with 19 product development practitioners were conducted, focussing on three topics: 1) the product development process and the integration of user involvement, 2) multidisciplinary teamwork, and 3) organizational attitude towards usability. Based on the interviews, context descriptions of the companies were created and barriers and enablers for usability were identified. To verify the findings and to discuss remaining issues a feedback workshop was held in which the primary contact from each company participated. The results indicate that differences in product-market combination lead to differences in organizational attitude towards usability. The prioritization of usability in an organization seems to be influenced by the degree of product complexity (complex products are more prone to suffer from usability issues) and whether developers think that usability is a purchase consideration for their clients. The product-market combination a company targets also affects the methods for user-centred design that a company can apply and that are relevant. What methods for user-centred design are used also seems to be influenced by the attitude towards usability: if usability is considered more important, methods that require more resources can be applied. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Usability test of an internet-based informatics tool for diabetes care providers: the comprehensive diabetes management program.

PubMed

Fonda, Stephanie J; Paulsen, Christine A; Perkins, Joan; Kedziora, Richard J; Rodbard, David; Bursell, Sven-Erik

2008-02-01

Research suggests Internet-based care management tools are associated with improvements in care and patient outcomes. However, although such tools change workflow, rarely is their usability addressed and reported. This article presents a usability study of an Internet-based informatics application called the Comprehensive Diabetes Management Program (CDMP), developed by content experts and technologists. Our aim is to demonstrate a process for conducting a usability study of such a tool and to report results. We conducted the usability test with six diabetes care providers under controlled conditions. Each provider worked with the CDMP in a single session using a "think aloud" process. Providers performed standardized tasks with fictitious patient data, and we observed how they approached these tasks, documenting verbalizations and subjective ratings. The providers then completed a usability questionnaire and interviews. Overall, the scores on the usability questionnaire were neutral to favorable. For specific subdomains of the questionnaire, the providers' reported problems with the application's ease of use, performance, and support features, but were satisfied with its visual appeal and content. The results from the observational and interview data indicated areas for improvement, particularly in navigation and terminology. The usability study identified several issues for improvement, confirming the need for usability testing of Internet-based informatics applications, even those developed by experts. To our knowledge, there have been no other usability studies of an Internet-based informatics application with the functionality of the CDMP. Such studies can form the foundation for translation of Internet-based medical informatics tools into clinical practice.

Usability Evaluation of An Electronic Medication Administration Record (eMAR) Application

PubMed Central

Guo, J.; Iribarren, S.; Kapsandoy, S.; Perri, S.; Staggers, N.

2011-01-01

Background Electronic medication administration records (eMARs) have been widely used in recent years. However, formal usability evaluations are not yet available for these vendor applications, especially from the perspective of nurses, the largest group of eMAR users. Objective To conduct a formal usability evaluation of an implemented eMAR. Methods Four evaluators examined a commercial vendor eMAR using heuristic evaluation techniques. The evaluators defined seven tasks typical of eMAR use and independently evaluated the application. Consensus techniques were used to obtain 100% agreement of identified usability problems and severity ratings. Findings were reviewed with 5 clinical staff nurses and the Director of Clinical Informatics who verified findings with a small group of clinical nurses. Results Evaluators found 60 usability problems categorized into 233 heuristic violations. Match, Error, and Visibility heuristics were the most frequently violated. Administer Medication and Order and Modify Medications tasks had the highest number of heuristic violations and usability problems rated as major or catastrophic. Conclusion The high number of usability problems could impact the effectiveness, efficiency and satisfaction of nurses’ medication administration activities and may include concerns about patient safety. Usability is a joint responsibility between sites and vendors. We offer a call to action for usability evaluations at all sites and eMAR application redesign as necessary to improve the user experience and promote patient safety. PMID:23616871

Reusable Software Usability Specifications for mHealth Applications.

PubMed

Cruz Zapata, Belén; Fernández-Alemán, José Luis; Toval, Ambrosio; Idri, Ali

2018-01-25

One of the key factors for the adoption of mobile technologies, and in particular of mobile health applications, is usability. A usable application will be easier to use and understand by users, and will improve user's interaction with it. This paper proposes a software requirements catalog for usable mobile health applications, which can be used for the development of new applications, or the evaluation of existing ones. The catalog is based on the main identified sources in literature on usability and mobile health applications. Our catalog was organized according to the ISO/IEC/IEEE 29148:2011 standard and follows the SIREN methodology to create reusable catalogs. The applicability of the catalog was verified by the creation of an audit method, which was used to perform the evaluation of a real app, S Health, application created by Samsung Electronics Co. The usability requirements catalog, along with the audit method, identified several usability flaws on the evaluated app, which scored 83%. Some flaws were detected in the app related to the navigation pattern. Some more issues related to the startup experience, empty screens or writing style were also found. The way a user navigates through an application improves or deteriorates user's experience with the application. We proposed a reusable usability catalog and an audit method. This proposal was used to evaluate a mobile health application. An audit report was created with the usability issues identified on the evaluated application.

Low-Cost Rapid Usability Testing: Its Application in Both Product Development and System Implementation.

PubMed

Kushniruk, Andre; Borycki, Elizabeth

2017-01-01

In recent years there has been considerable discussion around the need for certification and regulation of healthcare information technology (IT). In particular, the usability of the products being developed needs to be evaluated. This has included the application of standards designed to ensure the process of system development is user-centered and takes usability into consideration while a product is being developed. In addition to this, in healthcare, organizations in the United States and Europe have also addressed the need and requirement for product certification. However, despite these efforts there are continued reports of unusable and unsafe implementations. In this paper we discuss the need to not only include (and require) usability testing in the one-time development process of health IT products (such as EHRs), but we also argue for the need to additionally develop specific usability standards and requirements for usability testing during the implementation of vendor products (i.e. post product development) in healthcare settings. It is further argued that health IT products that may have been certified regarding their development process will still require application of usability testing in the process of implementing them in real hospital settings in order to ensure usability and safety. This is needed in order to ensure that the final result of both product development and implementation processes take into account and apply the latest usability principles and methods.

Usability in the real world: assessing medical information technologies in patients' homes.

PubMed

Kaufman, David R; Patel, Vimla L; Hilliman, Charlyn; Morin, Philip C; Pevzner, Jenia; Weinstock, Ruth S; Goland, Robin; Shea, Steven; Starren, Justin

2003-01-01

This paper presents an approach to usability evaluation of computer-based health care systems designed for patient use in their homes. Although such devices are becoming more prevalent, there is very little known about their usability. The theoretical foundations for the methods are discussed. The approach incorporates a cognitive walkthrough usability evaluation and new methods for usability testing that can be conducted in patient's homes. The method was applied to the IDEATel intervention, a multi-institution randomized controlled trial of the feasibility, acceptability, and clinical utility of a home-based telemedicine system for diabetic Medicare population. The usability study was designed to assess barriers to optimal use of the system. The focus was both on dimensions of the interface and on dimensions of patient skills and competency. The usability field research involved testing 25 patients in their homes using the system. The analysis included a range of video-analytic methods of varying levels of granularity. The usability evaluation revealed aspects of the interface that were sub-optimal and impeded the performance of certain tasks. It also found a range of patient-related factors such as numeracy and psychomotor skills that constituted barriers to productive use. A multifaceted usability approach provided important insight regarding use of technology by an elderly chronic-care patient population and more generally, for understanding how home health initiatives can more effectively use such technology.

Exploring the Role of Usability in the Software Process: A Study of Irish Software SMEs

NASA Astrophysics Data System (ADS)

O'Connor, Rory V.

This paper explores the software processes and usability techniques used by Small and Medium Enterprises (SMEs) that develop web applications. The significance of this research is that it looks at development processes used by SMEs in order to assess to what degree usability is integrated into the process. This study seeks to gain an understanding into the level of awareness of usability within SMEs today and their commitment to usability in practice. The motivation for this research is to explore the current development processes used by SMEs in developing web applications and to understand how usability is represented in those processes. The background for this research is provided by the growth of the web application industry beyond informational web sites to more sophisticated applications delivering a broad range of functionality. This paper presents an analysis of the practices of several Irish SMEs that develop web applications through a series of case studies. With the focus on SMEs that develop web applications as Management Information Systems and not E-Commerce sites, informational sites, online communities or web portals. This study gathered data about the usability techniques practiced by these companies and their awareness of usability in the context of the software process in those SMEs. The contribution of this study is to further the understanding of the current role of usability within the software development processes of SMEs that develop web applications.

Using a fuzzy comprehensive evaluation method to determine product usability: A proposed theoretical framework.

PubMed

Zhou, Ronggang; Chan, Alan H S

2017-01-01

In order to compare existing usability data to ideal goals or to that for other products, usability practitioners have tried to develop a framework for deriving an integrated metric. However, most current usability methods with this aim rely heavily on human judgment about the various attributes of a product, but often fail to take into account of the inherent uncertainties in these judgments in the evaluation process. This paper presents a universal method of usability evaluation by combining the analytic hierarchical process (AHP) and the fuzzy evaluation method. By integrating multiple sources of uncertain information during product usability evaluation, the method proposed here aims to derive an index that is structured hierarchically in terms of the three usability components of effectiveness, efficiency, and user satisfaction of a product. With consideration of the theoretical basis of fuzzy evaluation, a two-layer comprehensive evaluation index was first constructed. After the membership functions were determined by an expert panel, the evaluation appraisals were computed by using the fuzzy comprehensive evaluation technique model to characterize fuzzy human judgments. Then with the use of AHP, the weights of usability components were elicited from these experts. Compared to traditional usability evaluation methods, the major strength of the fuzzy method is that it captures the fuzziness and uncertainties in human judgments and provides an integrated framework that combines the vague judgments from multiple stages of a product evaluation process.

Second-harmonic generation of a dual-frequency laser in a MgO:PPLN crystal.

PubMed

Kang, Ying; Yang, Suhui; Brunel, Marc; Cheng, Lijun; Zhao, Changming; Zhang, Haiyang

2017-04-10

A dual-frequency CW laser at a wavelength of 1.064 μm is frequency doubled in a MgO:PPLN nonlinear crystal. The fundamental dual-frequency laser has a tunable beat note from 125 MHz to 175 MHz. A laser-diode pumped fiber amplifier is used to amplify the dual-frequency fundamental output to a maximum power of 50 W before frequency doubling. The maximum output power of the green light is 1.75 W when the input fundamental power is 12 W, corresponding to a frequency doubling efficiency of 14.6%. After frequency doubling, green light with modulation frequencies in two bands from 125 MHz to 175 MHz and from 250 MHz to 350 MHz is achieved simultaneously. The relative intensities of the beat notes at the two bands can be adjusted by changing the relative intensities at different frequencies of the fundamental light. The spectral width and frequency stabilities of the beat notes in fundamental wave and green light are also measured, respectively. The modulated green light has potential applications in underwater ranging, communication, and imaging.

Determining the Number of Participants Needed for the Usability Evaluation of E-Learning Resources: A Monte Carlo Simulation

ERIC Educational Resources Information Center

Davids, Mogamat Razeen; Harvey, Justin; Halperin, Mitchell L.; Chikte, Usuf M. E.

2015-01-01

The usability of computer interfaces has a major influence on learning. Optimising the usability of e-learning resources is therefore essential. However, this may be neglected because of time and monetary constraints. User testing is a common approach to usability evaluation and involves studying typical end-users interacting with the application…

Better bioinformatics through usability analysis.

PubMed

Bolchini, Davide; Finkelstein, Anthony; Perrone, Vito; Nagl, Sylvia

2009-02-01

Improving the usability of bioinformatics resources enables researchers to find, interact with, share, compare and manipulate important information more effectively and efficiently. It thus enables researchers to gain improved insights into biological processes with the potential, ultimately, of yielding new scientific results. Usability 'barriers' can pose significant obstacles to a satisfactory user experience and force researchers to spend unnecessary time and effort to complete their tasks. The number of online biological databases available is growing and there is an expanding community of diverse users. In this context there is an increasing need to ensure the highest standards of usability. Using 'state-of-the-art' usability evaluation methods, we have identified and characterized a sample of usability issues potentially relevant to web bioinformatics resources, in general. These specifically concern the design of the navigation and search mechanisms available to the user. The usability issues we have discovered in our substantial case studies are undermining the ability of users to find the information they need in their daily research activities. In addition to characterizing these issues, specific recommendations for improvements are proposed leveraging proven practices from web and usability engineering. The methods and approach we exemplify can be readily adopted by the developers of bioinformatics resources.

Current State of Agile User-Centered Design: A Survey

NASA Astrophysics Data System (ADS)

Hussain, Zahid; Slany, Wolfgang; Holzinger, Andreas

Agile software development methods are quite popular nowadays and are being adopted at an increasing rate in the industry every year. However, these methods are still lacking usability awareness in their development lifecycle, and the integration of usability/User-Centered Design (UCD) into agile methods is not adequately addressed. This paper presents the preliminary results of a recently conducted online survey regarding the current state of the integration of agile methods and usability/UCD. A world wide response of 92 practitioners was received. The results show that the majority of practitioners perceive that the integration of agile methods with usability/UCD has added value to their adopted processes and to their teams; has resulted in the improvement of usability and quality of the product developed; and has increased the satisfaction of the end-users of the product developed. The top most used HCI techniques are low-fidelity prototyping, conceptual designs, observational studies of users, usability expert evaluations, field studies, personas, rapid iterative testing, and laboratory usability testing.

Hello World! - Experiencing Usability Methods without Usability Expertise

NASA Astrophysics Data System (ADS)

Eriksson, Elina; Cajander, Åsa; Gulliksen, Jan

How do you do usability work when no usability expertise is available? What happens in an organization when system developers, with no previous HCI knowledge, after a 3-day course, start applying usability methods, and particularly field studies? In order to answer these questions qualitative data were gathered through participatory observations, a feed back survey, field study documentation and interviews from 47 system developers from a public authority. Our results suggest that field studies enhance the developer’s understanding of the user perspective, and provide a more holistic overview of the use situation, but that some developers were unable to interpret their observations and see solutions to the users’ problems. The field study method was very much appreciated and has now become standard operating procedure within the organization. However, although field studies may be useful, it does not replace the need for usability pro fes sion als, as their knowledge is essential for more complex observations, analysis and for keeping the focus on usability.

The use of think-aloud and instant data analysis in evaluation research: Exemplar and lessons learned.

PubMed

Joe, Jonathan; Chaudhuri, Shomir; Le, Thai; Thompson, Hilaire; Demiris, George

2015-08-01

While health information technologies have become increasingly popular, many have not been formally tested to ascertain their usability. Traditional rigorous methods take significant amounts of time and manpower to evaluate the usability of a system. In this paper, we evaluate the use of instant data analysis (IDA) as developed by Kjeldskov et al. to perform usability testing on a tool designed for older adults and caregivers. The IDA method is attractive because it takes significantly less time and manpower than the traditional usability testing methods. In this paper we demonstrate how IDA was used to evaluate usability of a multifunctional wellness tool, discuss study results and lessons learned while using this method. We also present findings from an extension of the method which allows the grouping of similar usability problems in an efficient manner. We found that the IDA method is a quick, relatively easy approach to identifying and ranking usability issues among health information technologies. Copyright © 2015 Elsevier Inc. All rights reserved.

A Comparison of What Is Part of Usability Testing in Three Countries

NASA Astrophysics Data System (ADS)

Clemmensen, Torkil

The cultural diversity of users of technology challenges our methods for usability evaluation. In this paper we report and compare three ethnographic interview studies of what is a part of a standard (typical) usability test in a company in Mumbai, Beijing and Copenhagen. At each of these three locations, we use structural and contrast questions do a taxonomic and paradigm analysis of a how a company performs a usability test. We find similar parts across the three locations. We also find different results for each location. In Mumbai, most parts of the usability test are not related to the interactive application that is tested, but to differences in user characteristics, test preparation, method, and location. In Copenhagen, considerations about the client's needs are part of a usability test. In Beijing, the only varying factor is the communication pattern and relation to the user. These results are then contrasted in a cross cultural matrix to identify cultural themes that can help interpret results from existing laboratory research in usability test methods.

Usability Evaluation of a Private Social Network on Mental Health for Relatives.

PubMed

Toribio-Guzmán, José Miguel; García-Holgado, Alicia; Soto Pérez, Felipe; García-Peñalvo, Francisco J; Franco Martín, Manuel

2017-09-01

Usability is one of the most prominent criteria that must be fulfilled by a software product. This study aims to evaluate the usability of SocialNet, a private social network for monitoring the daily progress of patients by their relatives, using a mixed usability approach: heuristic evaluation conducted by experts and user testing. A double heuristic evaluation with one expert evaluator identified the issues related to consistency, design, and privacy. User testing was conducted on 20 users and one evaluator using observation techniques and questionnaires. The main usability problems were found to be related to the structure of SocialNet, and the users presented some difficulties in locating the buttons or links. The results show a high level of usability and satisfaction with the product. This evaluation provides data on the usability of SocialNet based on the difficulties experienced by the users and the expert. The results help in redesigning the tool to resolve the identified problems as part of an iterative process.

Getting a Technology-based Diabetes Intervention Ready for Primetime: A Review of Usability Testing Studies

PubMed Central

Lyles, Courtney R.; Sarkar, Urmimala; Osborn, Chandra Y.

2014-01-01

Consumer health technologies can educate patients about diabetes and support their self-management, yet usability evidence is rarely published even though it determines patient engagement, optimal benefit of any intervention, and an understanding of generalizability. Therefore, we conducted a narrative review of peer-reviewed articles published from 2009–2013 that tested the usability of a web- or mobile-delivered system/application designed to educate and support patients with diabetes. Overall, the 23 papers included in our review used mixed (n=11), descriptive quantitative (n=9), and qualitative methods (n=3) to assess usability, such as documenting which features performed as intended and how patients rated their experiences. More sophisticated usability evaluations combined several complementary approaches to elucidate more aspects of functionality. Future work pertaining to the design and evaluation of technology-delivered diabetes education/support interventions should aim to standardize the usability testing processes, and publish usability findings to inform interpretation of why an intervention succeeded or failed, and for whom. PMID:25173689

Usability evaluation of Laboratory and Radiology Information Systems integrated into a hospital information system.

PubMed

Nabovati, Ehsan; Vakili-Arki, Hasan; Eslami, Saeid; Khajouei, Reza

2014-04-01

This study was conducted to evaluate the usability of widely used laboratory and radiology information systems. Three usability experts independently evaluated the user interfaces of Laboratory and Radiology Information Systems using heuristic evaluation method. They applied Nielsen's heuristics to identify and classify usability problems and Nielsen's severity rating to judge their severity. Overall, 116 unique heuristic violations were identified as usability problems. In terms of severity, 67 % of problems were rated as major and catastrophic. Among 10 heuristics, "consistency and standards" was violated most frequently. Moreover, mean severity of problems concerning "error prevention" and "help and documentation" heuristics was higher than of the others. Despite widespread use of specific healthcare information systems, they suffer from usability problems. Improving the usability of systems by following existing design standards and principles from the early phased of system development life cycle is recommended. Especially, it is recommended that the designers design systems that inhibit the initiation of erroneous actions and provide sufficient guidance to users.

End-Users' Voice in EHR Selection: Development of a Usability Questionnaire for Demonstrations in Procurement (DPUQ).

PubMed

Tyllinen, Mari; Kaipio, Johanna; Lääveri, Tinja; Nieminen, Marko

2017-01-01

This paper describes the development of a questionnaire for evaluating usability during EHR system procurement (DPUQ). Established usability questionnaires can be used to gather user feedback after using the systems. However, during procurement, experimenting with real system use is practical only with a limited number of system candidates. There is a need for less resource-demanding usability evaluation in the early stages of procurement in cases with several vendors. DPUQ has been designed for usability evaluation by end-users during special scenario-based vendor demonstrations. The questionnaire includes three sets of questions to be used during and after the vendor demonstration. DPUQ delivers specific usability scores and can be used to compare system candidates in procurement complementing other evaluation methods.

Design for Usability; practice-oriented research for user-centered product design.

PubMed

van Eijk, Daan; van Kuijk, Jasper; Hoolhorst, Frederik; Kim, Chajoong; Harkema, Christelle; Dorrestijn, Steven

2012-01-01

The Design for Usability project aims at improving the usability of electronic professional and consumer products by creating new methodology and methods for user-centred product development, which are feasible to apply in practice. The project was focused on 5 key areas: (i) design methodology, expanding the existing approach of scenario-based design to incorporate the interaction between product design, user characteristics, and user behaviour; (ii) company processes, barriers and enablers for usability in practice; (iii) user characteristics in relation to types of products and use-situations; (iv) usability decision-making; and (v) product impact on user behaviour. The project team developed methods and techniques in each of these areas to support the design of products with a high level of usability. This paper brings together and summarizes the findings.

Earth's magnetic field effect on MUF calculation and consequences for hmF2 trend estimates

NASA Astrophysics Data System (ADS)

Elias, Ana G.; Zossi, Bruno S.; Yiğit, Erdal; Saavedra, Zenon; de Haro Barbas, Blas F.

2017-10-01

Knowledge of the state of the upper atmosphere, and in particular of the ionosphere, is essential in several applications such as systems used in radio frequency communications, satellite positioning and navigation. In general, these systems depend on the state and evolution of the ionosphere. In all applications involving the ionosphere an essential task is to determine the path and modifications of ray propagation through the ionospheric plasma. The ionospheric refractive index and the maximum usable frequency (MUF) that can be received over a given distance are some key parameters that are crucial for such technological applications. However, currently the representation of these parameters are in general simplified, neglecting the effects of Earth's magnetic field. The value of M(3000)F2, related to the MUF that can be received over 3000 km is routinely scaled from ionograms using a technique which also neglects the geomagnetic field effects assuming a standard simplified propagation model. M(3000)F2 is expected to be affected by a systematic trend linked to the secular variations of Earth's magnetic field. On the other hand, among the upper atmospheric effects expected from increasing greenhouse gases concentration is the lowering of the F2-layer peak density height, hmF2. This ionospheric parameter is usually estimated using the M(3000)F2 factor, so it would also carry this ;systematic trend;. In this study, the geomagnetic field effect on MUF estimations is analyzed as well as its impact on hmF2 long-term trend estimations. We find that M(3000)F2 increases when the geomagnetic field is included in its calculation, and hence hmF2, estimated using existing methods involving no magnetic field for M(3000)F2 scaling, would present a weak but steady trend linked to these variations which would increase or compensate the few kilometers decrease ( 2 km per decade) expected from greenhouse gases effect.

A maximum likelihood algorithm for genome mapping of cytogenetic loci from meiotic configuration data.

PubMed Central

Reyes-Valdés, M H; Stelly, D M

1995-01-01

Frequencies of meiotic configurations in cytogenetic stocks are dependent on chiasma frequencies in segments defined by centromeres, breakpoints, and telomeres. The expectation maximization algorithm is proposed as a general method to perform maximum likelihood estimations of the chiasma frequencies in the intervals between such locations. The estimates can be translated via mapping functions into genetic maps of cytogenetic landmarks. One set of observational data was analyzed to exemplify application of these methods, results of which were largely concordant with other comparable data. The method was also tested by Monte Carlo simulation of frequencies of meiotic configurations from a monotelodisomic translocation heterozygote, assuming six different sample sizes. The estimate averages were always close to the values given initially to the parameters. The maximum likelihood estimation procedures can be extended readily to other kinds of cytogenetic stocks and allow the pooling of diverse cytogenetic data to collectively estimate lengths of segments, arms, and chromosomes. Images Fig. 1 PMID:7568226

The health systems' priority setting criteria for selecting health technologies: A systematic review of the current evidence

PubMed Central

Mobinizadeh, Mohammadreza; Raeissi, Pouran; Nasiripour, Amir Ashkan; Olyaeemanesh, Alireza; Tabibi, Seyed Jamaleddin

2016-01-01

Background: In the recent years, using health technologies to diagnose and treat diseases has had a considerable and accelerated growth. The proper use of these technologies may considerably help in the diagnosis and treatment of different diseases. On the other hand, unlimited and unrestricted entry of these technologies may result in induced demand by service providers. The aim of this study was to determine the appropriate criteria used in health technologies priority-setting models in the world. Methods: Using MESH and free text, we sought and retrieved the relevant articles from the most appropriate medical databases (the Cochrane Library, PubMed and Scopus) through three separate search strategies up to March 2015. The inclusion criteria were as follows: 1) Studies with specific criteria; 2) Articles written in English; 3) Those articles conducted in compliance with priority setting of health technologies. Data were analyzed qualitatively using a thematic synthesis technique. Results: After screening the retrieved papers via PRISMA framework, from the 7,012 papers, 40 studies were included in the final phase. Criteria for selecting health technologies (in pre assessment and in the assessment phase) were categorized into six main themes: 1) Health outcomes; 2) Disease and target population; 3) Technology alternatives; 4) Economic aspects; 5) Evidence; 6) and other factors. "Health effects/benefits" had the maximum frequency in health outcomes (8 studies); "disease severity" had the maximum frequency in disease and target population (12 studies); "the number of alternatives" had the maximum frequency in alternatives (2 studies); "cost-effectiveness" had the maximum frequency in economic aspects (15 studies); "quality of evidence" had the maximum frequency in evidence (4 studies); and "issues concerning the health system" had the maximum frequency in other factors (10 studies). Conclusion: The results revealed an increase in the number of studies on health technologies priority setting around the world, and emphasized the necessity of application of a multi- criteria approach for appropriate decision making about healthcare technologies in the health systems. PMID:27390699

A Framework for Usability Evaluation in EHR Procurement.

PubMed

Tyllinen, Mari; Kaipio, Johanna; Lääveri, Tinja

2018-01-01

Usability should be considered already by the procuring organizations when selecting future systems. In this paper, we present a framework for usability evaluation during electronic health record (EHR) system procurement. We describe the objectives of the evaluation, the procedure, selected usability attributes and the evaluation methods to measure them. We also present the emphasis usability had in the selection process. We do not elaborate on the details of the results, the application of methods or gathering of data. Instead we focus on the components of the framework to inform and give an example to other similar procurement projects.

A Guided Online and Mobile Self-Help Program for Individuals With Eating Disorders: An Iterative Engagement and Usability Study.

PubMed

Nitsch, Martina; Dimopoulos, Christina N; Flaschberger, Edith; Saffran, Kristina; Kruger, Jenna F; Garlock, Lindsay; Wilfley, Denise E; Taylor, Craig B; Jones, Megan

2016-01-11

Numerous digital health interventions have been developed for mental health promotion and intervention, including eating disorders. Efficacy of many interventions has been evaluated, yet knowledge about reasons for dropout and poor adherence is scarce. Most digital health intervention studies lack appropriate research design and methods to investigate individual engagement issues. User engagement and program usability are inextricably linked, making usability studies vital in understanding and improving engagement. The aim of this study was to explore engagement and corresponding usability issues of the Healthy Body Image Program-a guided online intervention for individuals with body image concerns or eating disorders. The secondary aim was to demonstrate the value of usability research in order to investigate engagement. We conducted an iterative usability study based on a mixed-methods approach, combining cognitive and semistructured interviews as well as questionnaires, prior to program launch. Two separate rounds of usability studies were completed, testing a total of 9 potential users. Thematic analysis and descriptive statistics were used to analyze the think-aloud tasks, interviews, and questionnaires. Participants were satisfied with the overall usability of the program. The average usability score was 77.5/100 for the first test round and improved to 83.1/100 after applying modifications for the second iteration. The analysis of the qualitative data revealed five central themes: layout, navigation, content, support, and engagement conditions. The first three themes highlight usability aspects of the program, while the latter two highlight engagement issues. An easy-to-use format, clear wording, the nature of guidance, and opportunity for interactivity were important issues related to usability. The coach support, time investment, and severity of users' symptoms, the program's features and effectiveness, trust, anonymity, and affordability were relevant to engagement. This study identified salient usability and engagement features associated with participant motivation to use the Healthy Body Image Program and ultimately helped improve the program prior to its implementation. This research demonstrates that improvements in usability and engagement can be achieved by testing and adjusting intervention design and content prior to program launch. The results are consistent with related research and reinforce the need for further research to identify usage patterns and effective means for reducing dropout. Digital health research should include usability studies prior to efficacy trials to help create more user-friendly programs that have a higher likelihood of "real-world" adoption.

Structured Light Based 3d Scanning for Specular Surface by the Combination of Gray Code and Phase Shifting

NASA Astrophysics Data System (ADS)

Zhang, Yujia; Yilmaz, Alper

2016-06-01

Surface reconstruction using coded structured light is considered one of the most reliable techniques for high-quality 3D scanning. With a calibrated projector-camera stereo system, a light pattern is projected onto the scene and imaged by the camera. Correspondences between projected and recovered patterns are computed in the decoding process, which is used to generate 3D point cloud of the surface. However, the indirect illumination effects on the surface, such as subsurface scattering and interreflections, will raise the difficulties in reconstruction. In this paper, we apply maximum min-SW gray code to reduce the indirect illumination effects of the specular surface. We also analysis the errors when comparing the maximum min-SW gray code and the conventional gray code, which justifies that the maximum min-SW gray code has significant superiority to reduce the indirect illumination effects. To achieve sub-pixel accuracy, we project high frequency sinusoidal patterns onto the scene simultaneously. But for specular surface, the high frequency patterns are susceptible to decoding errors. Incorrect decoding of high frequency patterns will result in a loss of depth resolution. Our method to resolve this problem is combining the low frequency maximum min-SW gray code and the high frequency phase shifting code, which achieves dense 3D reconstruction for specular surface. Our contributions include: (i) A complete setup of the structured light based 3D scanning system; (ii) A novel combination technique of the maximum min-SW gray code and phase shifting code. First, phase shifting decoding with sub-pixel accuracy. Then, the maximum min-SW gray code is used to resolve the ambiguity resolution. According to the experimental results and data analysis, our structured light based 3D scanning system enables high quality dense reconstruction of scenes with a small number of images. Qualitative and quantitative comparisons are performed to extract the advantages of our new combined coding method.

47 CFR 87.475 - Frequencies.

Code of Federal Regulations, 2013 CFR

2013-10-01

... to change frequency, power, location or emission. Each application must include the FAA Regional... 5031.0 MHz for microwave landing systems. Additionally, the frequencies in paragraph (b) of this... following conditions apply: (i) The maximum power authorized on the frequencies 108.150 and 334.550 MHz is 1...

47 CFR 87.475 - Frequencies.

Code of Federal Regulations, 2012 CFR

2012-10-01

... to change frequency, power, location or emission. Each application must include the FAA Regional... 5031.0 MHz for microwave landing systems. Additionally, the frequencies in paragraph (b) of this... following conditions apply: (i) The maximum power authorized on the frequencies 108.150 and 334.550 MHz is 1...

Features of the low-frequency polarization response in the region of the ferroelectric phase transition in multiferroic TbMnO 3

DOE PAGES

Trepakov, V. A.; Kvyatkovskii, O. E.; Savinov, M. E.; ...

2016-10-01

The unusual behavior of the low-frequency (10 Hz–1 MHz) permittivity in single crystals of ferroelectric multiferroic TbMnO3 has been experimentally and theoretically studied in detail in the region of the narrow temperature peak of the permittivity, associated with the ferroelectric phase transition (T C ~ 27.4 K). It has been found that the ε c(ω, T) maximum sharply decreases with increasing measured field frequency, while the temperature position of the maximum is independent of frequency. It has been shown that the observed features of the polarization response can be satisfactorily described within the Landau–Khalatnikov polarization relaxation theory.

CUNY+ Web: Usability Study of the Web-Based GUI Version of the Bibliographic Database of the City University of New York (CUNY).

ERIC Educational Resources Information Center

Oulanov, Alexei; Pajarillo, Edmund J. Y.

2002-01-01

Describes the usability evaluation of the CUNY (City University of New York) information system in Web and Graphical User Interface (GUI) versions. Compares results to an earlier usability study of the basic information database available on CUNY's wide-area network and describes the applicability of the previous usability instrument to this…

The Relationship between Personality Type and Software Usability Using the Myers-Briggs Type Indicator (MBTI) and the Software Usability Measurement Inventory (SUMI)

ERIC Educational Resources Information Center

Lindsey, William H.

2011-01-01

The study attempted to determine if there is a relationship between user's psychological personality types, measured by the Myers Briggs Type Indicator[R] (MBTI[R]) and distinct measures of usability measured by the Software Usability Measurement Inventory (SUMI). The study was expected to provide an answer to the following basic research…

Mapping Usability: A Critical Research Analysis of Trends in Software Usability Research, Theory, and Practice

ERIC Educational Resources Information Center

Sousa, Morgan Margaret

2009-01-01

The impetus for this project stemmed from a curiosity about two particular areas in the history of usability research. For one, I began research for this project with a desire to learn about patterns in the theory, practice, attitude, and perception about usability work, both in academic contexts and in corporate contexts, with a focus on the…

Effect of higher frequency on the classification of steady-state visual evoked potentials

NASA Astrophysics Data System (ADS)

Won, Dong-Ok; Hwang, Han-Jeong; Dähne, Sven; Müller, Klaus-Robert; Lee, Seong-Whan

2016-02-01

Objective. Most existing brain-computer interface (BCI) designs based on steady-state visual evoked potentials (SSVEPs) primarily use low frequency visual stimuli (e.g., <20 Hz) to elicit relatively high SSVEP amplitudes. While low frequency stimuli could evoke photosensitivity-based epileptic seizures, high frequency stimuli generally show less visual fatigue and no stimulus-related seizures. The fundamental objective of this study was to investigate the effect of stimulation frequency and duty-cycle on the usability of an SSVEP-based BCI system. Approach. We developed an SSVEP-based BCI speller using multiple LEDs flickering with low frequencies (6-14.9 Hz) with a duty-cycle of 50%, or higher frequencies (26-34.7 Hz) with duty-cycles of 50%, 60%, and 70%. The four different experimental conditions were tested with 26 subjects in order to investigate the impact of stimulation frequency and duty-cycle on performance and visual fatigue, and evaluated with a questionnaire survey. Resting state alpha powers were utilized to interpret our results from the neurophysiological point of view. Main results. The stimulation method employing higher frequencies not only showed less visual fatigue, but it also showed higher and more stable classification performance compared to that employing relatively lower frequencies. Different duty-cycles in the higher frequency stimulation conditions did not significantly affect visual fatigue, but a duty-cycle of 50% was a better choice with respect to performance. The performance of the higher frequency stimulation method was also less susceptible to resting state alpha powers, while that of the lower frequency stimulation method was negatively correlated with alpha powers. Significance. These results suggest that the use of higher frequency visual stimuli is more beneficial for performance improvement and stability as time passes when developing practical SSVEP-based BCI applications.

Effect of higher frequency on the classification of steady-state visual evoked potentials.

PubMed

Won, Dong-Ok; Hwang, Han-Jeong; Dähne, Sven; Müller, Klaus-Robert; Lee, Seong-Whan

2016-02-01

Most existing brain-computer interface (BCI) designs based on steady-state visual evoked potentials (SSVEPs) primarily use low frequency visual stimuli (e.g., <20 Hz) to elicit relatively high SSVEP amplitudes. While low frequency stimuli could evoke photosensitivity-based epileptic seizures, high frequency stimuli generally show less visual fatigue and no stimulus-related seizures. The fundamental objective of this study was to investigate the effect of stimulation frequency and duty-cycle on the usability of an SSVEP-based BCI system. We developed an SSVEP-based BCI speller using multiple LEDs flickering with low frequencies (6-14.9 Hz) with a duty-cycle of 50%, or higher frequencies (26-34.7 Hz) with duty-cycles of 50%, 60%, and 70%. The four different experimental conditions were tested with 26 subjects in order to investigate the impact of stimulation frequency and duty-cycle on performance and visual fatigue, and evaluated with a questionnaire survey. Resting state alpha powers were utilized to interpret our results from the neurophysiological point of view. The stimulation method employing higher frequencies not only showed less visual fatigue, but it also showed higher and more stable classification performance compared to that employing relatively lower frequencies. Different duty-cycles in the higher frequency stimulation conditions did not significantly affect visual fatigue, but a duty-cycle of 50% was a better choice with respect to performance. The performance of the higher frequency stimulation method was also less susceptible to resting state alpha powers, while that of the lower frequency stimulation method was negatively correlated with alpha powers. These results suggest that the use of higher frequency visual stimuli is more beneficial for performance improvement and stability as time passes when developing practical SSVEP-based BCI applications.

Usability study of the EduMod eLearning Program for contouring nodal stations of the head and neck.

PubMed

Deraniyagala, Rohan; Amdur, Robert J; Boyer, Arthur L; Kaylor, Scott

2015-01-01

A major strategy for improving radiation oncology education and competence evaluation is to develop eLearning programs that reproduce the real work environment. A valuable measure of the quality of an eLearning program is "usability," which is a multidimensional endpoint defined from the end user's perspective. The gold standard for measuring usability is the Software Usability Measurement Inventory (SUMI). The purpose of this study is to use the SUMI to measure usability of an eLearning course that uses innovative software to teach and test contouring of nodal stations of the head and neck. This is a prospective institutional review board-approved study in which all participants gave written informed consent. The study population was radiation oncology residents from 8 different programs across the United States. The subjects had to pass all sections of the same 2 eLearning modules and then complete the SUMI usability evaluation instrument. We reached the accrual goal of 25 participants. Usability results for the EduMod eLearning course, "Nodal Stations of the Head and Neck," were compared with a large database of scores of other major software programs. Results were evaluated in 5 domains: Affect, Helpfulness, Control, Learnability, and Global Usability. In all 5 domains, usability scores for the study modules were higher than the database mean and statistically superior in 4 domains. This is the first study to evaluate usability of an eLearning program related to radiation oncology. Usability of 2 representative modules related to contouring nodal stations of the head and neck was highly favorable, with scores that were superior to the industry standard in multiple domains. These results support the continued development of this type of eLearning program for teaching and testing radiation oncology technical skills. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Usability of clinical decision support system as a facilitator for learning the assistive technology adaptation process.

PubMed

Danial-Saad, Alexandra; Kuflik, Tsvi; Weiss, Patrice L Tamar; Schreuer, Naomi

2016-01-01

The aim of this study was to evaluate the usability of Ontology Supported Computerized Assistive Technology Recommender (OSCAR), a Clinical Decision Support System (CDSS) for the assistive technology adaptation process, its impact on learning the matching process, and to determine the relationship between its usability and learnability. Two groups of expert and novice clinicians (total, n = 26) took part in this study. Each group filled out system usability scale (SUS) to evaluate OSCAR's usability. The novice group completed a learning questionnaire to assess OSCAR's effect on their ability to learn the matching process. Both groups rated OSCAR's usability as "very good", (M [SUS] = 80.7, SD = 11.6, median = 83.7) by the novices, and (M [SUS] = 81.2, SD = 6.8, median = 81.2) by the experts. The Mann-Whitney results indicated that no significant differences were found between the expert and novice groups in terms of OSCAR's usability. A significant positive correlation existed between the usability of OSCAR and the ability to learn the adaptation process (rs = 0.46, p = 0.04). Usability is an important factor in the acceptance of a system. The successful application of user-centered design principles during the development of OSCAR may serve as a case study that models the significant elements to be considered, theoretically and practically in developing other systems. Implications for Rehabilitation Creating a CDSS with a focus on its usability is an important factor for its acceptance by its users. Successful usability outcomes can impact the learning process of the subject matter in general, and the AT prescription process in particular. The successful application of User-Centered Design principles during the development of OSCAR may serve as a case study that models the significant elements to be considered, theoretically and practically. The study emphasizes the importance of close collaboration between the developers and the end users.

Health Information Technology Usability Evaluation Scale (Health-ITUES) for Usability Assessment of Mobile Health Technology: Validation Study.

PubMed

Schnall, Rebecca; Cho, Hwayoung; Liu, Jianfang

2018-01-05

Mobile technology has become a ubiquitous technology and can be particularly useful in the delivery of health interventions. This technology can allow us to deliver interventions to scale, cover broad geographic areas, and deliver technologies in highly tailored ways based on the preferences or characteristics of users. The broad use of mobile technologies supports the need for usability assessments of these tools. Although there have been a number of usability assessment instruments developed, none have been validated for use with mobile technologies. The goal of this work was to validate the Health Information Technology Usability Evaluation Scale (Health-ITUES), a customizable usability assessment instrument in a sample of community-dwelling adults who were testing the use of a new mobile health (mHealth) technology. A sample of 92 community-dwelling adults living with HIV used a new mobile app for symptom self-management and completed the Health-ITUES to assess the usability of the app. They also completed the Post-Study System Usability Questionnaire (PSSUQ), a widely used and well-validated usability assessment tool. Correlations between these scales and each of the subscales were assessed. The subscales of the Health-ITUES showed high internal consistency reliability (Cronbach alpha=.85-.92). Each of the Health-ITUES subscales and the overall scale was moderately to strongly correlated with the PSSUQ scales (r=.46-.70), demonstrating the criterion validity of the Health-ITUES. The Health-ITUES has demonstrated reliability and validity for use in assessing the usability of mHealth technologies in community-dwelling adults living with a chronic illness. ©Rebecca Schnall, Hwayoung Cho, Jianfang Liu. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 05.01.2018.

Health Information Technology Usability Evaluation Scale (Health-ITUES) for Usability Assessment of Mobile Health Technology: Validation Study

PubMed Central

Cho, Hwayoung; Liu, Jianfang

2018-01-01

Background Mobile technology has become a ubiquitous technology and can be particularly useful in the delivery of health interventions. This technology can allow us to deliver interventions to scale, cover broad geographic areas, and deliver technologies in highly tailored ways based on the preferences or characteristics of users. The broad use of mobile technologies supports the need for usability assessments of these tools. Although there have been a number of usability assessment instruments developed, none have been validated for use with mobile technologies. Objective The goal of this work was to validate the Health Information Technology Usability Evaluation Scale (Health-ITUES), a customizable usability assessment instrument in a sample of community-dwelling adults who were testing the use of a new mobile health (mHealth) technology. Methods A sample of 92 community-dwelling adults living with HIV used a new mobile app for symptom self-management and completed the Health-ITUES to assess the usability of the app. They also completed the Post-Study System Usability Questionnaire (PSSUQ), a widely used and well-validated usability assessment tool. Correlations between these scales and each of the subscales were assessed. Results The subscales of the Health-ITUES showed high internal consistency reliability (Cronbach alpha=.85-.92). Each of the Health-ITUES subscales and the overall scale was moderately to strongly correlated with the PSSUQ scales (r=.46-.70), demonstrating the criterion validity of the Health-ITUES. Conclusions The Health-ITUES has demonstrated reliability and validity for use in assessing the usability of mHealth technologies in community-dwelling adults living with a chronic illness. PMID:29305343

13 CFR 113.3-3 - Structural accommodations for handicapped clients.

Code of Federal Regulations, 2011 CFR

2011-01-01

... accessible to and usable by persons with handicaps. Alterations to existing facilities that affect usability... permitted where substantially equivalent or greater access to and usability of the building is provided. (2...

You're a What? Usability Engineer.

ERIC Educational Resources Information Center

Crosby, Olivia

2001-01-01

Describes the work of usability engineers, who improve computer hardware, software, and websites by focusing on how users perceive and manipulate those tools. Discusses education, training, salaries, and talents needed by usability engineers. (Author/JOW)

Development of the Telehealth Usability Questionnaire (TUQ).

PubMed

Parmanto, Bambang; Lewis, Allen Nelson; Graham, Kristin M; Bertolet, Marnie H

2016-01-01

Current telehealth usability questionnaires are designed primarily for older technologies, where telehealth interaction is conducted over dedicated videoconferencing applications. However, telehealth services are increasingly conducted over computer-based systems that rely on commercial software and a user supplied computer interface. Therefore, a usability questionnaire that addresses the changes in telehealth service delivery and technology is needed. The Telehealth Usability Questionnaire (TUQ) was developed to evaluate the usability of telehealth implementation and services. This paper addresses: (1) the need for a new measure of telehealth usability, (2) the development of the TUQ, (3) intended uses for the TUQ, and (4) the reliability of the TUQ. Analyses indicate that the TUQ is a solid, robust, and versatile measure that can be used to measure the quality of the computer-based user interface and the quality of the telehealth interaction and services.

Effective Usability Engineering in Healthcare: A Vision of Usable and Safer Healthcare IT.

PubMed

Kushniruk, Andre; Senathirajah, Yalini; Borycki, Elizabeth

2017-01-01

Persistent problems with healthcare IT that is unusable and unsafe have been reported worldwide. In this paper we present our vision for deploying usability engineering in healthcare in a more substantive way in order to improve the current situation. The argument will be made that stronger and more substantial efforts need to be made to bring multiple usability engineering methods to bear on points in both system design and deployment (and not just as a one-time effort restricted to software product development). In addition, improved processes for ensuring the usability of commercial vendor-based systems being implemented in healthcare organizations need to be addressed. A discussion will also be provided on challenges and barriers that will need to be overcome to ensure that the heatlhcare IT that is released is both usable and safe.

Comparison of two kinds of interface, based on guided navigation or usability principles, for improving the adoption of computerized decision support systems: application to the prescription of antibiotics.

PubMed

Tsopra, Rosy; Jais, Jean-Philippe; Venot, Alain; Duclos, Catherine

2014-02-01

It is important to consider the way in which information is presented by the interfaces of clinical decision support systems, to favor the adoption of these systems by physicians. Interface design can focus on decision processes (guided navigation) or usability principles. The aim of this study was to compare these two approaches in terms of perceived usability, accuracy rate, and confidence in the system. We displayed clinical practice guidelines for antibiotic treatment via two types of interface, which we compared in a crossover design. General practitioners were asked to provide responses for 10 clinical cases and the System Usability Scale (SUS) for each interface. We assessed SUS scores, the number of correct responses, and the confidence level for each interface. SUS score and percentage confidence were significantly higher for the interface designed according to usability principles (81 vs 51, p=0.00004, and 88.8% vs 80.7%, p=0.004). The percentage of correct responses was similar for the two interfaces. The interface designed according to usability principles was perceived to be more usable and inspired greater confidence among physicians than the guided navigation interface. Consideration of usability principles in the construction of an interface--in particular 'effective information presentation', 'consistency', 'efficient interactions', 'effective use of language', and 'minimizing cognitive load'--seemed to improve perceived usability and confidence in the system.

Using a fuzzy comprehensive evaluation method to determine product usability: A proposed theoretical framework

PubMed Central

Zhou, Ronggang; Chan, Alan H. S.

2016-01-01

BACKGROUND: In order to compare existing usability data to ideal goals or to that for other products, usability practitioners have tried to develop a framework for deriving an integrated metric. However, most current usability methods with this aim rely heavily on human judgment about the various attributes of a product, but often fail to take into account of the inherent uncertainties in these judgments in the evaluation process. OBJECTIVE: This paper presents a universal method of usability evaluation by combining the analytic hierarchical process (AHP) and the fuzzy evaluation method. By integrating multiple sources of uncertain information during product usability evaluation, the method proposed here aims to derive an index that is structured hierarchically in terms of the three usability components of effectiveness, efficiency, and user satisfaction of a product. METHODS: With consideration of the theoretical basis of fuzzy evaluation, a two-layer comprehensive evaluation index was first constructed. After the membership functions were determined by an expert panel, the evaluation appraisals were computed by using the fuzzy comprehensive evaluation technique model to characterize fuzzy human judgments. Then with the use of AHP, the weights of usability components were elicited from these experts. RESULTS AND CONCLUSIONS: Compared to traditional usability evaluation methods, the major strength of the fuzzy method is that it captures the fuzziness and uncertainties in human judgments and provides an integrated framework that combines the vague judgments from multiple stages of a product evaluation process. PMID:28035943

A New Cloud and Aerosol Layer Detection Method Based on Micropulse Lidar Measurements

NASA Astrophysics Data System (ADS)

Wang, Q.; Zhao, C.; Wang, Y.; Li, Z.; Wang, Z.; Liu, D.

2014-12-01

A new algorithm is developed to detect aerosols and clouds based on micropulse lidar (MPL) measurements. In this method, a semi-discretization processing (SDP) technique is first used to inhibit the impact of increasing noise with distance, then a value distribution equalization (VDE) method is introduced to reduce the magnitude of signal variations with distance. Combined with empirical threshold values, clouds and aerosols are detected and separated. This method can detect clouds and aerosols with high accuracy, although classification of aerosols and clouds is sensitive to the thresholds selected. Compared with the existing Atmospheric Radiation Measurement (ARM) program lidar-based cloud product, the new method detects more high clouds. The algorithm was applied to a year of observations at both the U.S. Southern Great Plains (SGP) and China Taihu site. At SGP, the cloud frequency shows a clear seasonal variation with maximum values in winter and spring, and shows bi-modal vertical distributions with maximum frequency at around 3-6 km and 8-12 km. The annual averaged cloud frequency is about 50%. By contrast, the cloud frequency at Taihu shows no clear seasonal variation and the maximum frequency is at around 1 km. The annual averaged cloud frequency is about 15% higher than that at SGP.

The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

DOE Office of Scientific and Technical Information (OSTI.GOV)

Visser, P. J. de, E-mail: p.j.devisser@tudelft.nl; Yates, S. J. C.; Guruswamy, T.

2015-06-22

We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the gap edge of the superconductor. From there on, the response drops to half the maximum response at twice the pair-breaking energy. At higher frequencies, the response rises again due to trapping of pair-breaking phonons in the superconductor. In practice, this is a measurement of the frequency dependence of the quasiparticle creationmore » efficiency due to pair-breaking in a superconductor. The efficiency, calculated from the different non-equilibrium quasiparticle distribution functions at each frequency, is in agreement with the measurements.« less

Usability and clinical efficacy of diabetes mobile applications for adults with type 2 diabetes: A systematic review.

PubMed

Fu, Helen; McMahon, Siobhan K; Gross, Cynthia R; Adam, Terrence J; Wyman, Jean F

2017-09-01

To assess the usability and clinical effectiveness of diabetes mobile applications (diabetes apps) developed for adults with type 2 diabetes. A systematic review of the usability and effectiveness of diabetes apps was conducted. Searches were performed using MEDLINE, EMBASE, COMPENDEX, and IEEE XPLORE for articles published from January 1, 2011, to January 17, 2017. Search terms included: diabetes, mobile apps, and mobile health (mHealth). The search yielded 723 abstracts of which seven usability studies and ten clinical effectiveness studies met the inclusion criteria from 20 publications. Usability, as measured by satisfaction ratings from experts and patients, ranged from 38% to 80%. Usability problem ratings ranged from moderate to catastrophic. Top usability problems are multi-steps task, limited functionality and interaction, and difficult system navigation. Clinical effectiveness, measured by reductions in HbA1c, ranged from 0.15% to 1.9%. Despite meager satisfaction ratings and major usability problems, there is some limited evidence supporting the effectiveness of diabetes apps to improve glycemic control for adults with type 2 diabetes. Findings strongly suggest that efforts to improve user satisfaction, incorporate established principles of health behavior change, and match apps to user characteristics will increase the therapeutic impact of diabetes apps. Copyright © 2017 Elsevier B.V. All rights reserved.

Web usability evaluation on BloobIS website by using hallway usability testing method and ISO 9241:11

NASA Astrophysics Data System (ADS)

Dwi Susanto, Tony; Ingesti Prasetyo, Anisa; Astuti, Hanim Maria

2018-03-01

At this moment, the need for web as an information media is highly important. Not only confined in the infotainment area, government, and education, but health as well uses the web media as a medium for providing information effectively. BloobIS is a web based application which integrates blood supply and distribution information at the Blood Transfusion Unit. Knowing how easy information is on BloobIS is marked by how convenient the website is used. Up until now, the BloobIS website is nearing completion but testing has not yet been performed to users and is on the testing and development phase in the Development Life Cycle software. Thus, an evaluation namely the quality control software which focuses on the perspective of BloobIs web usability is required. Hallway Usability Testing and ISO 9241:11 are the methods chosen to measure the BloobIS application usability. The expected outputs of the quality control software focusing on the usability evaluation are being able to rectify the usability deficiencies on the BloobIs web and provide recommendations to develop the web as a basic BloobIS web quality upgraed which sets a goal to amplify the satisfaction of web users based on usability factors in ISO 9241:11.

AlGaN/GaN-HEMTs with a breakdown voltage higher than 100 V and maximum oscillation frequency f{sub max} as high as 100 GHz

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mokerov, V. G., E-mail: vgmokerov@yandex.ru; Kuznetsov, A. L.; Fedorov, Yu. V.

2009-04-15

The N-Al{sub 0.27}Ga{sub 0.73}N/GaN High Electron Mobility Transistors (HEMTs) with different gate lengths L{sub g} (ranging from 170 nm to 0.5 {mu}m) and gate widths W{sub s} (ranging from 100 to 1200 {mu}m) have been studied. The S parameters have been measured; these parameters have been used to determine the current-gain cutoff frequency f{sub t}, the maximum oscillation frequency f{sub max}, and the power gain MSG/MAG and Mason's coefficients were investigated in the frequency range from 10 MHz to 67 GHz in relation to the gate length and gate width. It was found that the frequencies f{sub t} and f{submore » max} attain their maximum values of f{sub t} = 48 GHz and f{sub max} = 100 GHz at L{sub g} = 170 nm and W{sub g} = 100 {mu}m. The optimum values of W{sub g} and output power P out of the basic transistors have been determined for different frequencies of operation. It has also been demonstrated that the 170 nm Al{sub 0.27}Ga{sub 0.73}N/GaN HEMT technology provides both good frequency characteristics and high breakdown voltages and is very promising for high-frequency applications (up to 40 GHz)« less

40 CFR Table 3 to Subpart Ec of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2014 CFR

2014-07-01

... filter Wet scrubber Dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge rate Continuous 1×hour ✔ ✔ ✔ Maximum fabric filter inlet temperature Continuous 1×minute...

40 CFR Table 3 to Subpart Ec of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2013 CFR

2013-07-01

... filter Wet scrubber Dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge rate Continuous 1×hour ✔ ✔ ✔ Maximum fabric filter inlet temperature Continuous 1×minute...

Optimal use of electrophysiological indicators of muscular effort and fatigue

NASA Technical Reports Server (NTRS)

Updike, O. L.

1981-01-01

Electromyograms (EMG) from working muscles convey information on effort and fatigue. Their application, e.g., to assess the demands of vehicle control tasks, is complicated by the cooperative action of sets of muscles, by both intrinsic and imposed filtering, and by numerous other sources of variation. Fourier analyses of these noise like signals offer one approach to interpretation; downward spectral shifts accompany fatigue. Techniques are being sought (in both time and frequency domains) for further condensing the wideband EMG signals, while retaining essential information, into a concise 'state vector' usable in comparing control system designs.

Microprocessor controlled proof-mass actuator

NASA Technical Reports Server (NTRS)

Horner, Garnett C.

1987-01-01

The objective of the microprocessor controlled proof-mass actuator is to develop the capability to mount a small programmable device on laboratory models. This capability will allow research in the active control of flexible structures. The approach in developing the actuator will be to mount all components as a single unit. All sensors, electronic and control devices will be mounted with the actuator. The goal for the force output capability of the actuator will be one pound force. The programmable force actuator developed has approximately a one pound force capability over the usable frequency range, which is above 2 Hz.

Monolithic carrier-envelope phase-stabilization scheme.

PubMed

Fuji, Takao; Rauschenberger, Jens; Apolonski, Alexander; Yakovlev, Vladislav S; Tempea, Gabriel; Udem, Thomas; Gohle, Christoph; Hänsch, Theodor W; Lehnert, Walter; Scherer, Michael; Krausz, Ferenc

2005-02-01

A new scheme for stabilizing the carrier-envelope (CE) phase of a few-cycle laser pulse train is demonstrated. Self-phase modulation and difference-frequency generation in a single periodically poled lithium niobate crystal that transmits the main laser beam allows CE phase locking directly in the usable output. The monolithic scheme obviates the need for splitting off a fraction of the laser output for CE phase control, coupling into microstructured fiber, and separation and recombination of spectral components. As a consequence, the output yields 6-fs, 800-nm pulses with an unprecedented degree of short- and long-term reproducibility of the electric field waveform.

Interface Usability Across and Within EHR Vendors and Medical Settings: The Often Unexamined Need for Interface Similarities.

PubMed

Koppel, Ross; Kuziemsky, Craig

2017-01-01

Usability of health information technology (HIT), if considered at all, is usually focused on individual providers, settings and vendors. However, in light of transformative models of healthcare delivery such as collaborative care delivery that crosses providers and settings, we need to think of usability as a collective and constantly emerging process. To address this new reality we develop a matrix of usability that spans several dimensions and contexts, incorporating differing vendors, user, settings, disciplines, and display configurations. The matrix, while conceptual, extends existing work by providing the means for discussion of usability issues and needs beyond one setting and one user type.

Quantitative analysis of biological tissues using Fourier transform-second-harmonic generation imaging

NASA Astrophysics Data System (ADS)

Ambekar Ramachandra Rao, Raghu; Mehta, Monal R.; Toussaint, Kimani C., Jr.

2010-02-01

We demonstrate the use of Fourier transform-second-harmonic generation (FT-SHG) imaging of collagen fibers as a means of performing quantitative analysis of obtained images of selected spatial regions in porcine trachea, ear, and cornea. Two quantitative markers, preferred orientation and maximum spatial frequency are proposed for differentiating structural information between various spatial regions of interest in the specimens. The ear shows consistent maximum spatial frequency and orientation as also observed in its real-space image. However, there are observable changes in the orientation and minimum feature size of fibers in the trachea indicating a more random organization. Finally, the analysis is applied to a 3D image stack of the cornea. It is shown that the standard deviation of the orientation is sensitive to the randomness in fiber orientation. Regions with variations in the maximum spatial frequency, but with relatively constant orientation, suggest that maximum spatial frequency is useful as an independent quantitative marker. We emphasize that FT-SHG is a simple, yet powerful, tool for extracting information from images that is not obvious in real space. This technique can be used as a quantitative biomarker to assess the structure of collagen fibers that may change due to damage from disease or physical injury.

External morphology and calling song characteristics in Tibicen plebejus (Hemiptera: Cicadidae).

PubMed

Mehdipour, Maedeh; Sendi, Jalal Jalali; Zamanian, Hossein

2015-02-01

Tibicen plebejus is the largest cicada native to the ecosystem in northern Iran. The male cicada produces a loud calling song for attracting females from a long distance. It is presumed that the female selects a mate based on a combination of passive and active mechanisms, but it is not known if she selects for size, nor if the male's size correlates with any characteristic of the advertisement call. In this study, we report the relationship between calling song features and morphological characters in the male of T. plebejus. Research was conducted in northern Iran during the summer of 2010. Seventeen males were collected and their calling songs were recorded in a natural environment. Two morphological characters were measured: length and weight. Maximum, minimum and average of values of 10 key acoustic variables of the calling song were analyzed: phrase duration, phrase part 1, phrase part 2, number of phrases per minute, echeme duration, echeme period, interecheme interval, number of echeme per second, echeme/intereheme ratio, and dominant frequency. The data were tested for the level of association between morphology and acoustic variables using simple linear regression. In conclusion, in terms of song structure, three significant positive correlations existed between length and (1) mean echeme duration, (2) mean echeme/interecheme ratio, (3) maximum echeme/interecheme ratio. We found out also four significant negative correlations between both length and weight with (1) minimum interecheme intervals, (2) mean dominant frequency, (3) minimum dominant frequency, (4) maximum dominant frequency, and between weight and (1) minimum interecheme intervals, (2) mean dominant frequency, (3) minimum dominant frequency, (4) maximum dominant frequency. It can be found that larger males of T. plebejus produce songs of lower frequency and are less silent between echemes. Copyright © 2014 Académie des sciences. Published by Elsevier SAS. All rights reserved.

LATCH usability in vehicles.

DOT National Transportation Integrated Search

2012-04-01

This project investigated the usability of Lower Anchors and Tethers for CHildren (LATCH) hardware by measuring LATCH implementations in 98 2011 or 2010 model-year vehicles. ISO and SAE LATCH usability rating systems were used to assess all vehicles ...

Optimal behavior of viscoelastic flow at resonant frequencies.

PubMed

Lambert, A A; Ibáñez, G; Cuevas, S; del Río, J A

2004-11-01

The global entropy generation rate in the zero-mean oscillatory flow of a Maxwell fluid in a pipe is analyzed with the aim of determining its behavior at resonant flow conditions. This quantity is calculated explicitly using the analytic expression for the velocity field and assuming isothermal conditions. The global entropy generation rate shows well-defined peaks at the resonant frequencies where the flow displays maximum velocities. It was found that resonant frequencies can be considered optimal in the sense that they maximize the power transmitted to the pulsating flow at the expense of maximum dissipation.

Applying usability testing techniques to improve a health promotion website.

PubMed

Hinchliffe, Anetta; Mummery, W Kerry

2008-04-01

Use of the Internet for health promotion is increasing; however, the lack of published research regarding website usability suggests that health promotion websites are being developed without consultation with their users or formal evaluation. This study conducted usability testing of an existing health promotion website to inform modifications and to identify common usability themes that should be addressed by organisations developing or maintaining a health promotion website. A combination of qualitative and quantitative techniques were implemented during the usability testing sessions to gather data from users while completing tasks on the website. Techniques included performance measures (time taken), direct observation (participant observation) and subjective user preferences (questionnaire and interview). Improvements to the website were measured in terms of reduced problems reported, reduced time taken to complete tasks and increased subjective reports. Seven usability themes emerged from the data: design, feedback, format, instructions, navigation, terminology and learnability. This study demonstrates the application of usability testing to the design and modification of a health promotion website and illustrates the areas or themes that can be used as a framework for testing and modification.

National questionnaire study on clinical ICT systems proofs: physicians suffer from poor usability.

PubMed

Viitanen, Johanna; Hyppönen, Hannele; Lääveri, Tinja; Vänskä, Jukka; Reponen, Jarmo; Winblad, Ilkka

2011-10-01

In the health informatics field, usability studies typically focus on evaluating a single information system and involve a rather small group of end-users. However, little is known about the usability of clinical information and communication technology (ICT) environment in which healthcare professionals work daily. This paper aims at contributing to usability research and user-oriented development of healthcare technologies with three objectives: inform researchers and practitioners about the current state of usability of clinical ICT systems, increase the understanding of usability aspects specific for clinical context, and encourage a more holistic approach on studying usability issues in health informatics field. A national web questionnaire study was conducted in Finland in spring 2010 with 3929 physicians actively working in patient care. For the purposes of the study, we described three dimensions of clinical ICT system usability that reflect the physicians' viewpoint on system usage: (1) compatibility between clinical ICT systems and physicians' tasks, (2) ICT support for information exchange, communication and collaboration in clinical work, and (3) interoperability and reliability. The dimensions derive from the definitions of usability and clinical context of use analysis, and reflect the ability of ICT systems to have a positive impact on patient care by supporting physicians in achieving their goals with a pleasant user experience. The research data incorporated 32 statements with a five-point Likert-scale on physicians' experiences on usability of their currently used ICT systems and a summative question about school grade given to electronic health record (EHR) systems. Physicians' estimates of their EHR systems were very critical. With the rating scale from 4 or fail to 10 or excellent, the average of the grades varied from 6.1 to 8.4 dependent on the kind of facility the physician is working. Questionnaire results indicated several usability problems and deficiencies which considerably hindered the efficiency of clinical ICT use and physician's routine work. Systems lacked the appropriate features to support typical clinical tasks, such as decision making, prevention of medical errors, and review of a patient's treatment chart. The systems also required physicians to perform fixed sequences of steps and tasks, and poorly supported the documentation and retrieval of patient data. The findings on ICT support for collaboration showed mainly negative results, aside from collaboration between co-located physicians. In addition, the study results pointed out physicians suffering from system failures and a lack of integration between the systems. The described study and related results are unique in several ways. A national usability study with nearly 4000 respondents had not been conducted in other countries in which healthcare technologies are widely adopted. The questionnaire study provided a generalized picture about the usability problems, however, it should be noted that there were significant differences between legacy systems in use. Previously, researchers had not approached contextual aspects of usability the context of clinical work, where numerous systems are in use. The described usability dimensions and the presented study results can be considered as the first step towards conceptualizing ICT usability in the unique setting of clinical work. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Finite-Element Modelling of the Acoustic Input Admittance of the Newborn Ear Canal and Middle Ear.

PubMed

Motallebzadeh, Hamid; Maftoon, Nima; Pitaro, Jacob; Funnell, W Robert J; Daniel, Sam J

2017-02-01

Admittance measurement is a promising tool for evaluating the status of the middle ear in newborns. However, the newborn ear is anatomically very different from the adult one, and the acoustic input admittance is different than in adults. To aid in understanding the differences, a finite-element model of the newborn ear canal and middle ear was developed and its behaviour was studied for frequencies up to 2000 Hz. Material properties were taken from previous measurements and estimates. The simulation results were within the range of clinical admittance measurements made in newborns. Sensitivity analyses of the material properties show that in the canal model, the maximum admittance and the frequency at which that maximum admittance occurs are affected mainly by the stiffness parameter; in the middle-ear model, the damping is as important as the stiffness in influencing the maximum admittance magnitude but its effect on the corresponding frequency is negligible. Scaling up the geometries increases the admittance magnitude and shifts the resonances to lower frequencies. The results suggest that admittance measurements can provide more information about the condition of the middle ear when made at multiple frequencies around its resonance.

A Persuasive and Social mHealth Application for Physical Activity: A Usability and Feasibility Study

PubMed Central

Al Ayubi, Soleh U; Branch, Robert; Ding, Dan

2014-01-01

Background Advances in smartphones and the wide usage of social networking systems offer opportunities for the development of innovative interventions to promote physical activity. To that end, we developed a persuasive and social mHealth application designed to monitor and motivate users to walk more every day. Objective The objectives of this project were to conduct a focused review on the fundamental characteristics of mHealth for physical activity promotion, to develop an mHealth application that meets such characteristics, and to conduct a feasibility study to deploy the application in everyday life. Methods This project started as an analytical study to review the fundamental characteristics of the technologies used in physical activity monitoring and promotion. Then, it was followed by a technical development of the application. Next, a 4 week deployment was conducted where participants used the application as part of their daily life. A think-aloud method and in-depth semistructured interviews were conducted following the deployment. A qualitative description method was used to thematically analyze the interviews. Feasibility measures included, adherence to the program, user-system interactions, motivation to use, and experience with physical activity and online social interactions. Results There were seven fundamental characteristics of physical activity monitoring and promotion that were identified, which were then used as a foundation to develop the application. There were fourteen participants that enrolled in the application evaluation. The age range was from 24 to 45; body mass index ranged from 18.5 to 42.98, with 4 of the subjects falling into the category “obese”. Half of them were experienced with smartphones, and all were familiar with a social network system. There were thirteen participants that completed the study; one was excluded. Overall, participants gave high scores to almost all of the usability factors examined, with averages of 4.52 out of a 5.00 maximum. Over 29 days, participants used the application for a total of 119,380 minutes (average=7.57 hours/day/participant; SD 1.56). Conclusions Based on the fundamental characteristics, the application was successfully developed. The usability results suggest that the system is usable and user satisfaction was high. Deploying the application was shown to be feasible for the promotion of daily physical activity. PMID:25099928

A Persuasive and Social mHealth Application for Physical Activity: A Usability and Feasibility Study.

PubMed

Al Ayubi, Soleh U; Parmanto, Bambang; Branch, Robert; Ding, Dan

2014-05-22

Advances in smartphones and the wide usage of social networking systems offer opportunities for the development of innovative interventions to promote physical activity. To that end, we developed a persuasive and social mHealth application designed to monitor and motivate users to walk more every day. The objectives of this project were to conduct a focused review on the fundamental characteristics of mHealth for physical activity promotion, to develop an mHealth application that meets such characteristics, and to conduct a feasibility study to deploy the application in everyday life. This project started as an analytical study to review the fundamental characteristics of the technologies used in physical activity monitoring and promotion. Then, it was followed by a technical development of the application. Next, a 4 week deployment was conducted where participants used the application as part of their daily life. A think-aloud method and in-depth semistructured interviews were conducted following the deployment. A qualitative description method was used to thematically analyze the interviews. Feasibility measures included, adherence to the program, user-system interactions, motivation to use, and experience with physical activity and online social interactions. There were seven fundamental characteristics of physical activity monitoring and promotion that were identified, which were then used as a foundation to develop the application. There were fourteen participants that enrolled in the application evaluation. The age range was from 24 to 45; body mass index ranged from 18.5 to 42.98, with 4 of the subjects falling into the category "obese". Half of them were experienced with smartphones, and all were familiar with a social network system. There were thirteen participants that completed the study; one was excluded. Overall, participants gave high scores to almost all of the usability factors examined, with averages of 4.52 out of a 5.00 maximum. Over 29 days, participants used the application for a total of 119,380 minutes (average=7.57 hours/day/participant; SD 1.56). Based on the fundamental characteristics, the application was successfully developed. The usability results suggest that the system is usable and user satisfaction was high. Deploying the application was shown to be feasible for the promotion of daily physical activity.

Assessment of diet and physical activity of brazilian schoolchildren: usability testing of a web-based questionnaire.

PubMed

da Costa, Filipe Ferreira; Schmoelz, Camilie Pacheco; Davies, Vanessa Fernandes; Di Pietro, Patrícia Faria; Kupek, Emil; de Assis, Maria Alice Altenburg

2013-08-19

Information and communication technology (ICT) has been used with increasing frequency for the assessment of diet and physical activity in health surveys. A number of Web-based questionnaires have been developed for children and adolescents. However, their usability characteristics have scarcely been reported, despite their potential importance for improving the feasibility and validity of ICT-based methods. The objective of this study was to describe the usability evaluation of the Consumo Alimentar e Atividade Física de Escolares (CAAFE) questionnaire (Food Consumption and Physical Activity Questionnaire for schoolchildren), a new Web-based survey tool for the self-assessment of diet and physical activity by schoolchildren. A total of 114 schoolchildren aged 6 to 12 years took part in questionnaire usability testing carried out in computer classrooms at five elementary schools in the city of Florianopolis, Brazil. Schoolchildren used a personal computer (PC) equipped with software for recording what is on the computer screen and the children's speech during usability testing. Quantitative and qualitative analyses took into account objective usability metrics such as error counts and time to complete a task. Data on the main difficulties in accomplishing the task and the level of satisfaction expressed by the children were assessed by the observers using a standardized form and interviews with the children. Descriptive statistics and content analysis were used to summarize both the quantitative and the qualitative aspects of the data obtained. The mean time for completing the questionnaire was 13.7 minutes (SD 3.68). Compared to the children in 2nd or 3rd grades, those in 4th or 5th grades spent less time completing the questionnaire (median 12.4 vs 13.3 minutes, P=.022), asked for help less frequently (median 0 vs 1.0 count, P=.005), had a lower error count (median 2.0 vs 8.0 count, P<.001), and obtained a higher overall performance score (median 73.0 vs 68.0, P=.005). Children with a PC at home spent less time completing the questionnaire (median 12.3 vs 14.9 minutes, P<.001), had a lower overall error count (median 2.0 vs 9.0 count, P=.03), and had a higher performance score (median 72.0 vs 64.0, P=.005) compared to the children without a PC at home. The most common difficulty in completing the questionnaire was in using the scroll bar. The majority of children reported a positive evaluation (liked a lot or liked) for the four design elements, which were evaluated. The results of the present study provided feedback to improve the final version of the CAAFE questionnaire. Quantitative data showed minor errors and system failures, while qualitative data indicated that, overall, the children enjoyed the CAAFE questionnaire. Grade levels and PC use must be taken into account in Web-based tools designed for children.

A knitted garment using intarsia technique for Heart Rate Variability biofeedback: Evaluation of initial prototype.

PubMed

Abtahi, F; Ji, G; Lu, K; Rödby, K; Seoane, F

2015-01-01

Heart rate variability (HRV) biofeedback is a method based on paced breathing at specific rate called resonance frequency by giving online feedbacks from user respiration and its effect on HRV. Since the HRV is also influence by different factors like stress and emotions, stress related to an unfamiliar measurement device, cables and skin electrodes may cover the underling effect of such kind of intervention. Wearable systems are usually considered as intuitive solutions which are more familiar to the end-user and can help to improve usability and hence reducing the stress. In this work, a prototype of a knitted garment using intarsia technique is developed and evaluated. Results show the satisfactory level of quality for Electrocardiogram and thoracic electrical bioimpedance i.e. for respiration monitoring as a part of HRV biofeedback system. Using intarsia technique and conductive yarn for making the connection instead of cables will reduce the complexity of fabrication in textile production and hence reduce the final costs in a final commercial product. Further development of garment and Android application is ongoing and usability and efficiency of final prototype will be evaluated in detail.

Graphical content of medicinal package inserts: an exploratory study to evaluate potential legibility issues.

PubMed

Pires, Carla; Vigário, Marina; Cavaco, Afonso

2016-06-01

The graphical content of the Medicines Package Inserts (MPIs), such as illustrations and typographic features should be legible and appropriate, as required by international pharmaceutical regulations. To study: (1) the frequency and type of MPIs' key graphic elements, (2) their compliance with regulations and (3) how educated people understand them. Descriptive study: characterisation of the graphical content of 651 MPIs. Usability study: illustrations and tables (purposively selected) were evaluated with questionnaires in three groups of humanities undergraduates (illustrations only, illustrations plus text and text only). Descriptive study: illustrations and tables were respectively identified in 6.3% and 11.8% of the MPIs. The illustrations were mainly related to how to take/use the medicine. Non-recommended graphical representations were found (e.g. italic or underline). Usability test: legibility issues were identified, especially for the group of isolated illustrations. The scarce use of illustrations and tables possibly affected the legibility of the MPIs. Compulsory legibility tests are needed to guarantee the MPIs' proper use, thus contributing to a safe use of medicines. Overall, this study highlighted the need to carefully revise/assess the MPIs' design and probably increase health information experts' awareness on this issue. © 2015 Health Libraries Group.

47 CFR 74.637 - Emissions and emission limitations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... vestigial sideband AM video: On any frequency removed from the center frequency of the authorized band by... communications. Frequency Band (MHz) Maximum authorized bandwidth (MHz) 1,990 to 2,110 18 6,425 to 6,525 25 6,875...

47 CFR 74.637 - Emissions and emission limitations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... vestigial sideband AM video: On any frequency removed from the center frequency of the authorized band by... communications. Frequency Band (MHz) Maximum authorized bandwidth (MHz) 1,990 to 2,110 18 6,425 to 6,525 25 6,875...

47 CFR 74.637 - Emissions and emission limitations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... vestigial sideband AM video: On any frequency removed from the center frequency of the authorized band by... communications. Frequency Band (MHz) Maximum authorized bandwidth (MHz) 1,990 to 2,110 18 6,425 to 6,525 25 6,875...

47 CFR 74.637 - Emissions and emission limitations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... vestigial sideband AM video: On any frequency removed from the center frequency of the authorized band by... communications. Frequency Band (MHz) Maximum authorized bandwidth (MHz) 1,990 to 2,110 18 6,425 to 6,525 25 6,875...

47 CFR 74.637 - Emissions and emission limitations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... vestigial sideband AM video: On any frequency removed from the center frequency of the authorized band by... communications. Frequency Band (MHz) Maximum authorized bandwidth (MHz) 1,990 to 2,110 18 6,425 to 6,525 25 6,875...

Investigating the effect of m-commerce design usability on customers' trust

NASA Astrophysics Data System (ADS)

Hussain, Azham Bin; Mahmood, Alaa Thamer; Naser, Raed Kamil

2017-10-01

User experience may vary from one user to another based on the design characteristics for processing a certain task. Our review of the literature revealed that there is a noticeable lack of studies on the effect of mobile or m-commerce design usability on customers' trust to perform certain activities. We investigated the effect of m-commerce design usability in terms of navigability, supportability, readability, creditability, and content relevant. A close-ended questionnaire was distributed to 20 customers who were asked to perform some tasks. The result showed that majority of the participants found m-commerce design usability to influence their trust of the app. The mentioned usability elements were found to positively influence customers' trust except for supportability. Our findings provide some insights to the m-commerce designers and developers and extend the current understanding about the potential of design usability in explaining users' usage behavior.

Usability of Low-Cost Android Data Collection System for Community-Based Participatory Research.

PubMed

Salihu, Hamisu M; Salinas-Miranda, Abraham; Turner, DeAnne; King, Lindsey; Paothong, Arnut; Austin, Deborah; Berry, Estrellita Lo

2016-01-01

Android tablet computers can be valuable tools for data collection, but their usability has not been evaluated in community-based participatory research (CBPR). This article examines the usability of a low-cost bilingual touchscreen computerized survey system using Android tablets, piloted with a sample of 201 community residents in Tampa, Florida, from November 2013 to March 2014. Needs assessment questions were designed with the droidSURVEY software, and deployed using Android tablet computers. In addition, participants were asked questions about system usability. The mean system usability was 77.57 ± 17.66 (range, 0-100). The mean completion time for taking the 63 survey questions in the needs assessment was 23.11 ± 9.62 minutes. The survey completion rate was optimal (100%), with only 6.34% missingness per variable. We found no sociodemographic differences in usability scores. Our findings indicate that Android tablets could serve as useful tools in CBPR studies.

Usability engineering: domain analysis activities for augmented-reality systems

NASA Astrophysics Data System (ADS)

Gabbard, Joseph; Swan, J. E., II; Hix, Deborah; Lanzagorta, Marco O.; Livingston, Mark; Brown, Dennis B.; Julier, Simon J.

2002-05-01

This paper discusses our usability engineering process for the Battlefield Augmented Reality System (BARS). Usability engineering is a structured, iterative, stepwise development process. Like the related disciplines of software and systems engineering, usability engineering is a combination of management principals and techniques, formal and semi- formal evaluation techniques, and computerized tools. BARS is an outdoor augmented reality system that displays heads- up battlefield intelligence information to a dismounted warrior. The paper discusses our general usability engineering process. We originally developed the process in the context of virtual reality applications, but in this work we are adapting the procedures to an augmented reality system. The focus of this paper is our work on domain analysis, the first activity of the usability engineering process. We describe our plans for and our progress to date on our domain analysis for BARS. We give results in terms of a specific urban battlefield use case we have designed.

Frequency Domain Beamforming for a Deep Space Network Downlink Array

NASA Technical Reports Server (NTRS)

Navarro, Robert

2012-01-01

This paper describes a frequency domain beamformer to array up to 8 antennas of NASA's Deep Space Network currently in development. The objective of this array is to replace and enhance the capability of the DSN 70m antennas with multiple 34m antennas for telemetry, navigation and radio science use. The array will coherently combine the entire 500 MHz of usable bandwidth available to DSN receivers. A frequency domain beamforming architecture was chosen over a time domain based architecture to handle the large signal bandwidth and efficiently perform delay and phase calibration. The antennas of the DSN are spaced far enough apart that random atmospheric and phase variations between antennas need to be calibrated out on an ongoing basis in real-time. The calibration is done using measurements obtained from a correlator. This DSN Downlink Array expands upon a proof of concept breadboard array built previously to develop the technology and will become an operational asset of the Deep Space Network. Design parameters for frequency channelization, array calibration and delay corrections will be presented as well a method to efficiently calibrate the array for both wide and narrow bandwidth telemetry.

Automatic analysis of ciliary beat frequency using optical flow

NASA Astrophysics Data System (ADS)

Figl, Michael; Lechner, Manuel; Werther, Tobias; Horak, Fritz; Hummel, Johann; Birkfellner, Wolfgang

2012-02-01

Ciliary beat frequency (CBF) can be a useful parameter for diagnosis of several diseases, as e.g. primary ciliary dyskinesia. (PCD). CBF computation is usually done using manual evaluation of high speed video sequences, a tedious, observer dependent, and not very accurate procedure. We used the OpenCV's pyramidal implementation of the Lukas-Kanade algorithm for optical flow computation and applied this to certain objects to follow the movements. The objects were chosen by their contrast applying the corner detection by Shi and Tomasi. Discrimination between background/noise and cilia by a frequency histogram allowed to compute the CBF. Frequency analysis was done using the Fourier transform in matlab. The correct number of Fourier summands was found by the slope in an approximation curve. The method showed to be usable to distinguish between healthy and diseased samples. However there remain difficulties in automatically identifying the cilia, and also in finding enough high contrast cilia in the image. Furthermore the some of the higher contrast cilia are lost (and sometimes found) by the method, an easy way to distinguish the correct sub-path of a point's path have yet to be found in the case where the slope methods doesn't work.

Prostate Cancer on the Web-Expedient Tool for Patients' Decision-Making?

PubMed

Borgmann, Hendrik; Wölm, Jan-Henning; Vallo, Stefan; Mager, Rene; Huber, Johannes; Breyer, Johannes; Salem, Johannes; Loeb, Stacy; Haferkamp, Axel; Tsaur, Igor

2017-03-01

Many patients diagnosed with cancer search for health information on the Web. We aimed to assess the quality and reliability of online health information on prostate cancer. Google, Yahoo, and Bing were searched for the term "prostate cancer." After selecting the most frequented websites, quality was measured by DISCERN score, JAMA benchmark criteria, and presence of HONcode certification. Popularity was assessed by Alexa tool, while accessibility, usability, and reliability were investigated by LIDA tool. Readability was analyzed by Flesch-Kincaid Reading Grade Level and Automated Readability Index. All 13 selected websites were rated as being of high quality according to the DISCERN instrument (76.5 ± 2.6 out of 80 points). JAMA benchmark criteria were fulfilled by 87 % of websites, whereas only 37 % were certified by the HONcode. Median Alexa Traffic Rank was 2718 ranging from 7 to 679,038. Websites received 2.3 ± 0.5 daily pageviews per visitor and users spent an average of 2 min 58 s ± 39 sec on the website. Accessibility (92 ± 5 %) and usability (92 ± 3 %) scores were high and reliability (88 ± 8 %) moderate according to the LIDA tool. Flesch-Kincaid Grade Level was 7.9 ± 2.2, and Automated Readability Index was 7.5 ± 2.4, rating the websites as fairly difficult to read. In conclusion, quality, accessibility, and usability of websites on prostate cancer provided a high rating in the current analysis. These findings are encouraging in view of the growing frequency of patients' access of health information online.

User perspectives on the usability of a regional health information exchange

PubMed Central

Ho, Yun-Xian; Cala, Cather Marie; Blakemore, Dana; Chen, Qingxia; Frisse, Mark E; Johnson, Kevin B

2011-01-01

Objective We assessed the usability of a health information exchange (HIE) in a densely populated metropolitan region. This grant-funded HIE had been deployed rapidly to address the imminent needs of the patient population and the need to draw wider participation from regional entities. Design We conducted a cross-sectional survey of individuals given access to the HIE at participating organizations and examined some of the usability and usage factors related to the technology acceptance model. Measurements We probed user perceptions using the Questionnaire for User Interaction Satisfaction, an author-generated Trust scale, and user characteristic questions (eg, age, weekly system usage time). Results Overall, users viewed the system favorably (ratings for all usability items were greater than neutral (one-sample Wilcoxon test, p<0.0014, Bonferroni-corrected for 35 tests). System usage was regressed on usability, trust, and demographic and user characteristic factors. Three usability factors were positively predictive of system usage: overall reactions (p<0 0.01), learning (p<0.05), and system functionality (p<0.01). Although trust is an important component in collaborative relationships, we did not find that user trust of other participating healthcare entities was significantly predictive of usage. An analysis of respondents' comments revealed ways to improve the HIE. Conclusion We used a rapid deployment model to develop an HIE and found that perceptions of system usability were positive. We also found that system usage was predicted well by some aspects of usability. Results from this study suggest that a rapid development approach may serve as a viable model for developing usable HIEs serving communities with limited resources. PMID:21622933

Why Citizen Science Without Usability Testing Will Underperform

NASA Astrophysics Data System (ADS)

Romano, C.; Gay, P.; Owens, R.; Burlea, G.

2017-12-01

Citizen science projects must undergo usability testing and optimization if they are to meet their stated goals. This presentation will include video of usability tests conducted upon citizen science websites. Usability testing is essential to the success of online interaction, however, citizen science projects have just begun to include this critical activity. Interaction standards in citizen science lag behind those of commercial interests, and published research on this topic is limited. Since online citizen science is by definition, an exchange of information, a clear understanding of how users experience an online project is essential to informed decision-making. Usability testing provides that insight. Usability testing collects data via direct observation of a person while she interacts with a digital product, such as a citizen science website. The test participant verbalizes her thoughts while using the website or application; the moderator follows the participant and captures quantitative measurement of the participant's confidence of success as she advances through the citizen science project. Over 15 years of usability testing, we have observed that users who do not report a consistent sense of progress are likely to abandon a website after as few as three unrewarding interactions. Since citizen science is also a voluntary activity, ensuring seamless interaction for users is mandatory. Usability studies conducted on citizen science websites demonstrate that project teams frequently underestimate a user's need for context and ease of use. Without usability testing, risks to online citizen science projects include high bounce rate (users leave the website without taking any action), abandonment (of the website, tutorials, registration), misunderstanding instructions (causing disorientation and erroneous conclusions), and ultimately, underperforming projects.

Pattern mining of user interaction logs for a post-deployment usability evaluation of a radiology PACS client.

PubMed

Jorritsma, Wiard; Cnossen, Fokie; Dierckx, Rudi A; Oudkerk, Matthijs; van Ooijen, Peter M A

2016-01-01

To perform a post-deployment usability evaluation of a radiology Picture Archiving and Communication System (PACS) client based on pattern mining of user interaction log data, and to assess the usefulness of this approach compared to a field study. All user actions performed on the PACS client were logged for four months. A data mining technique called closed sequential pattern mining was used to automatically extract frequently occurring interaction patterns from the log data. These patterns were used to identify usability issues with the PACS. The results of this evaluation were compared to the results of a field study based usability evaluation of the same PACS client. The interaction patterns revealed four usability issues: (1) the display protocols do not function properly, (2) the line measurement tool stays active until another tool is selected, rather than being deactivated after one use, (3) the PACS's built-in 3D functionality does not allow users to effectively perform certain 3D-related tasks, (4) users underuse the PACS's customization possibilities. All usability issues identified based on the log data were also found in the field study, which identified 48 issues in total. Post-deployment usability evaluation based on pattern mining of user interaction log data provides useful insights into the way users interact with the radiology PACS client. However, it reveals few usability issues compared to a field study and should therefore not be used as the sole method of usability evaluation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Interdisciplinary development of manual and automated product usability assessments for older adults with dementia: lessons learned.

PubMed

Boger, Jennifer; Taati, Babak; Mihailidis, Alex

2016-10-01

The changes in cognitive abilities that accompany dementia can make it difficult to use everyday products that are required to complete activities of daily living. Products that are inherently more usable for people with dementia could facilitate independent activity completion, thus reducing the need for caregiver assistance. The objectives of this research were to: (1) gain an understanding of how water tap design impacted tap usability and (2) create an automated computerized tool that could assess tap usability. 27 older adults, who ranged from cognitively intact to advanced dementia, completed 1309 trials on five tap designs. Data were manually analyzed to investigate tap usability as well as used to develop an automated usability analysis tool. Researchers collaborated to modify existing techniques and to create novel ones to accomplish both goals. This paper presents lessons learned through the course of this research, which could be applicable in the development of other usability studies, automated vision-based assessments and the development of assistive technologies for cognitively impaired older adults. Collaborative interdisciplinary teamwork, which included older adult with dementia participants, was key to enabling innovative advances that achieved the projects' research goals. Implications for Rehabilitation Products that are implicitly familiar and usable by older adults could foster independent activity completion, potentially reducing reliance on a caregiver. The computer-based automated tool can significantly reduce the time and effort required to perform product usability analysis, making this type of analysis more feasible. Interdisciplinary collaboration can result in a more holistic understanding of assistive technology research challenges and enable innovative solutions.

Comparison of two kinds of interface, based on guided navigation or usability principles, for improving the adoption of computerized decision support systems: application to the prescription of antibiotics

PubMed Central

Tsopra, Rosy; Jais, Jean-Philippe; Venot, Alain; Duclos, Catherine

2014-01-01

Context It is important to consider the way in which information is presented by the interfaces of clinical decision support systems, to favor the adoption of these systems by physicians. Interface design can focus on decision processes (guided navigation) or usability principles. Objective The aim of this study was to compare these two approaches in terms of perceived usability, accuracy rate, and confidence in the system. Materials and methods We displayed clinical practice guidelines for antibiotic treatment via two types of interface, which we compared in a crossover design. General practitioners were asked to provide responses for 10 clinical cases and the System Usability Scale (SUS) for each interface. We assessed SUS scores, the number of correct responses, and the confidence level for each interface. Results SUS score and percentage confidence were significantly higher for the interface designed according to usability principles (81 vs 51, p=0.00004, and 88.8% vs 80.7%, p=0.004). The percentage of correct responses was similar for the two interfaces. Discussion/conclusion The interface designed according to usability principles was perceived to be more usable and inspired greater confidence among physicians than the guided navigation interface. Consideration of usability principles in the construction of an interface—in particular ‘effective information presentation’, ‘consistency’, ‘efficient interactions’, ‘effective use of language’, and ‘minimizing cognitive load’—seemed to improve perceived usability and confidence in the system. PMID:24008427

Frequency dependence of the maximum operating temperature for quantum-cascade lasers up to 5.4 THz

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wienold, M.; Humboldt Universität zu Berlin, Institut für Physik, Newtonstr. 15, 12489 Berlin; Deutsches Zentrum für Luft und Raumfahrt, Rutherfordstr. 2, 12489 Berlin

2015-11-16

We report on the observation of an approximately linear reduction in the maximum operating temperature with an increasing emission frequency for terahertz quantum-cascade lasers between 4.2 and 5.4 THz. These lasers are based on the same design type, but vary in period length and barrier height for the cascade structure. The sample emitting at the highest frequency around 5.4 THz can be operated in pulsed mode up to 56 K. We identify an additional relaxation channel for electrons by longitudinal optical phonon scattering from the upper to the lower laser level and increasing optical losses toward higher frequencies as major processes,more » leading to the observed temperature behavior.« less

2-Step Maximum Likelihood Channel Estimation for Multicode DS-CDMA with Frequency-Domain Equalization

NASA Astrophysics Data System (ADS)

Kojima, Yohei; Takeda, Kazuaki; Adachi, Fumiyuki

Frequency-domain equalization (FDE) based on the minimum mean square error (MMSE) criterion can provide better downlink bit error rate (BER) performance of direct sequence code division multiple access (DS-CDMA) than the conventional rake combining in a frequency-selective fading channel. FDE requires accurate channel estimation. In this paper, we propose a new 2-step maximum likelihood channel estimation (MLCE) for DS-CDMA with FDE in a very slow frequency-selective fading environment. The 1st step uses the conventional pilot-assisted MMSE-CE and the 2nd step carries out the MLCE using decision feedback from the 1st step. The BER performance improvement achieved by 2-step MLCE over pilot assisted MMSE-CE is confirmed by computer simulation.

Using Heuristic Evaluation to Improve Sepsis Alert Usability.

PubMed

Pertiwi, Ariani Arista Putri; Fraczkowski, Dan; Stogis, Sheryl L; Lopez, Karen Dunn

2018-06-01

Sepsis, life-threatening organ dysfunction in response to infection, is an alarmingly common and aggressive illness in US hospitals, especially for intensive care patients. Preventing sepsis deaths rests on the clinicians' ability to promptly recognize and treat sepsis. To aid early recognition, many organizations have employed clinician-facing electronic sepsis alert systems. However, the effectiveness of the alert relies on heavily on the visual interface, textual information, and overall usability. This article reports a usability inspection of a sepsis alert system. The authors found violations in 12 of the 14 usability principles and promote use of this method in practice to systematically identify usability problems. Copyright © 2018 Elsevier Inc. All rights reserved.

Field Evaluation of Programmable Thermostats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sachs, O.; Tiefenbeck, V.; Duvier, C.

2012-12-01

Prior research suggests that poor programmable thermostats usability may prevent their effective use to save energy. We hypothesized that home occupants with a high-usability thermostats would be more likely to use them to save energy than people with a basic thermostat. We randomly installed a high-usability thermostat in half the 77 apartments of an affordable housing complex, installing a basic thermostat in the other half. During the heating season, we collected space temperature and furnace on-off data to evaluate occupant interaction with the thermostats, foremost nighttime setbacks. We found that thermostat usability did not influence energy-saving behaviors, finding no significantmore » difference in temperature maintained among apartments with high- and low-usability thermostats.« less

Usability Evaluation of Multimedia Courseware (MEL-SindD)

NASA Astrophysics Data System (ADS)

Yussof, Rahmah Lob; Badioze Zaman, Halimah

Constructive evaluations on any software are needed to ensure the effectiveness and usability of the software. This assesment on the multimedia courseware is part of the researcher's study towards the development and usability of the early reading software for students with Down Syndrome (MEL-SindD). This paper will discuss the usability assesment of this courseware, the methods used for the evaluation as well as suitable approaches that can be deployed to evaluate the courseware effectiveness to disabled children.

A Usability Study of Users’ Perceptions Toward a Multimedia Computer-Assisted Learning Tool for Neuroanatomy

PubMed Central

Gould, Douglas J.; Terrell, Mark A.; Fleming, Jo

2015-01-01

This usability study evaluated users’ perceptions of a multimedia prototype for a new e-learning tool: Anatomy of the Central Nervous System: A Multimedia Course. Usability testing is a collection of formative evaluation methods that inform the developmental design of e-learning tools to maximize user acceptance, satisfaction, and adoption. Sixty-two study participants piloted the prototype and completed a usability questionnaire designed to measure two usability properties: program need and program applicability. Statistical analyses were used to test the hypothesis that the multimedia prototype was well designed and highly usable, it was perceived as: 1) highly needed across a spectrum of educational contexts, 2) highly applicable in supporting the pedagogical processes of teaching and learning neuroanatomy, and 3) was highly usable by all types of users. Three independent variables represented user differences: level of expertise (faculty vs. student), age, and gender. Analysis of the results supports the research hypotheses that the prototype was designed well for different types of users in various educational contexts and for supporting the pedagogy of neuroanatomy. In addition, the results suggest that the multimedia program will be most useful as a neuroanatomy review tool for health-professions students preparing for licensing or board exams. This study demonstrates the importance of integrating quality properties of usability with principles of human learning during the instructional design process for multimedia products. PMID:19177405

U.S.A.B.I.L.I.T.Y. Framework for Older Adults.

PubMed

Caboral-Stevens, Meriam; Whetsell, Martha V; Evangelista, Lorraine S; Cypress, Brigitte; Nickitas, Donna

2015-01-01

The purpose of the current study was to present a framework to determine potential usability of health websites by older adults. Review of the literature showed paucity of nursing theory related to the use of technology and usability, particularly in older adults. The Roy Adaptation Model, a widely used nursing theory, was chosen to provide framework for the new model. Technology constructs from the Technology Acceptance Model and United Theory of Acceptance and Use of Technology and behavioral control construct from the Theory of Planned Behavior were integrated into the construction of the derived model. The Use of Technology for Adaptation by Older Adults and/or Those With Limited Literacy (U.S.A.B.I.L.I.T.Y.) Model was constructed from the integration of diverse theoretical/conceptual perspectives. The four determinants of usability in the conceptual model include (a) efficiency, (b) learnability, (c) perceived user experience, and (d) perceived control. Because of the lack of well-validated survey questionnaires to measure these determinants, a U.S.A.B.I.L.I.T.Y. Survey was developed. A panel of experts evaluated face and content validity of the new instrument. Internal consistency of the new instrument was 0.96. Usability is key to accepting technology. The derived U.S.A.B.I.L.I.T.Y. framework could serve as a guide for nurses in formative evaluation of technology. Copyright 2015, SLACK Incorporated.

A Re-evaluation of Discarded Deceased Donor Kidneys in the UK: Are Usable Organs Still Being Discarded?

PubMed

Mittal, Shruti; Adamusiak, Anna; Horsfield, Catherine; Loukopoulos, Ioannis; Karydis, Nikolaos; Kessaris, Nicos; Drage, Martin; Olsburgh, Jonathon; Watson, Christopher Je; Callaghan, Chris J

2017-07-01

A significant proportion of procured deceased donor kidneys are subsequently discarded. The UK Kidney Fast-Track Scheme (KFTS) was introduced in 2012, enabling kidneys at risk of discard to be simultaneously offered to participating centers. We undertook an analysis of discarded kidneys to determine if unnecessary organ discard was still occurring since the KFTS was introduced. Between April and June 2015, senior surgeons independently inspected 31 consecutive discarded kidneys from throughout the United Kingdom. All kidneys were biopsied. Organs were categorized as usable, possibly usable pending histology, or not usable for implantation. After histology reports were available, final assessments of usability were made. There were 19 donors (6 donations after brain death, 13 donations after circulatory death), with a median (range) donor age of 67 (29-83) years and Kidney Donor Profile Index of 93 (19-100). Reasons for discard were variable. Only 3 discarded kidneys had not entered the KFTS. After initial assessment postdiscard, 11 kidneys were assessed as usable, with 9 kidneys thought to be possibly usable. Consideration of histological data reduced the number of kidneys thought usable to 10 (10/31; 32%). The KFTS scheme is successfully identifying organs at high risk of discard, though potentially transplantable organs are still being discarded. Analyses of discarded organs are essential to identify barriers to organ utilization and develop strategies to reduce unnecessary discard.

Cloud and convection frequencies over the southeast United States as related to small-scale geographic features

NASA Technical Reports Server (NTRS)

Gibson, Harold M.; Vonder Haar, Thomas H.

1990-01-01

Based on relatively high spatial and temporal resolution satelite data collected at 0700 CST and at each hour from 1000 CST to 1700 CST during the summer of 1986, cloud and convection variations over the area from Mississippi east to Georgia and from the Gulf of Mexico north to Tennessee are discussed. The data analyses show an average maximum cloud frequency over the land areas at 1400 local time and a maximum of deep convection one hour later. Both cloudiness and deep convection are found to be at a maximum during the nocturnal hours over the Gulf of Mexico. Cloud frequency shows a strong relationship to small terrain features. Small fresh water bodies have cloud minima relative to the surroundings in the afternoon hours. Higher, steep terrain shows cloud maxima and the adjacent lower terrain exhibits afternoon cloud minima due to a divergence of mountain breeze caused by the valley.

Preferred modes in jets: comparison between different measures of the receptivity

NASA Astrophysics Data System (ADS)

Garnaud, Xavier; Lesshafft, Lutz; Schmid, Peter J.; Huerre, Patrick

2012-11-01

The response of jets to frequency forcing is usually measured experimentally in terms of the maximum amplitude of velocity fluctuations reached along the axis (Crow & Champagne (1971)). In the present work, the preferred mode of isothermal jets is discussed in terms of the linear flow response to time-harmonic forcing (Trefethen et al. (1993)). The optimal frequency response is computed for different choices of the objective functional: the usual energy (L2) norm and the maximum amplitude over the entire domain (L∞ norm). The relevance and limitations of the different objective functionals are critically analyzed. Although the dominant flow structures are robustly identified in all cases, the measure of the flow response in terms of the maximum amplitude does not suffer from the continually slow axial growth of low frequency perturbations. The financial support of the EADS Foundation is gratefully acknowledged.

Magnitude and frequency of floods in Nebraska

USGS Publications Warehouse

Beckman, Emil W.

1976-01-01

Observed maximum flood peaks at 303 gaging stations with 13 or more years of record and significant peaks at 57 short-term stations and 31 miscellaneous sites are useful in designing flood-control works for maximum safety from flood damage. Comparison is made with maximum observed floods in the United States.

A study of the use of vibration and stress wave sensing for the detection of bearing failure

NASA Technical Reports Server (NTRS)

Ensor, L. C.; Feng, C. C.

1975-01-01

Results from an experimental study of vibrations and stress waves emitted from ball bearings are presented. Fatique tests were run with both high quality bearings and man faulted bearings, all of one size. Tests were instrumented with different sensors to detect the noises from 10 Hz to 1 MHz. Frequency spectrum plots are presented. The modulation characteristics of the ultrasonic noises were analyzed, and acoustic emission type measurements were conducted. Results are presented which show that there are usable acoustic signal levels even beyond 500 KHz. These signal levels are modulated by a low frequency carrier which is a function of the stress loading and acoustic transmissibility. The results were correlated to fault size in the bearings. The correlation shows that the sensor used for signals from 100 KHz to 1 MHz gave the best sensitivity and detected the generation of very small spalls or pits.

Determining Usability Versus Cost and Yields of a Regional Transport

NASA Technical Reports Server (NTRS)

Gvozdenovic, Slobodan

1999-01-01

Regional transports are designed to operate on air networks having the basic characteristics of short trip distances and low density passengers/cargo, i.e. small numbers of passengers per flight. Regional transports passenger capacity is from 10 to 100 seats and operate on routes from 350 to 1000 nautical miles (nm). In order to meet passenger requirements providing low fares and high or required number of frequencies, airlines must constantly monitor operational costs and keep them low. It is obvious that costs of operating aircraft must be lower than yield obtained by transporting passengers and cargo. The requirement to achieve favorable yield/cost ratio must provide the answer to the question of which aircraft will best meet a specific air network (Simpson, 1972). An air network is defined by the number of services, the trip distance of each service, and the number of flights (frequencies) per day and week.

Host-specific variation in infection by toxigenic fungi and contamination by mycotoxins in pearl millet and corn.

PubMed

Wilson, J P; Jurjevic, Z; Hanna, W W; Wilson, D M; Potter, T L; Coy, A E

2006-02-01

Pearl millet is widely consumed in regions of Africa and Asia, and is increasingly being grown as an alternative grain in drought-prone regions of the United States. Pearl millet and corn were grown in dryland conditions at Tifton, Georgia, USA and grains were compared for pre-harvest infection by potentially toxigenic fungi and contamination by mycotoxins. Corn hybrids Agripro 9909 and Pioneer 3146, and pearl millet Tifgrain 102 were grown in 2000 and 2001; pearl millet HGM 100 was included in the test in 2001. Hybrids were sown on multiple planting dates in each year to induce variation in flowering time. Host species differed in the frequency of isolation of potentially toxigenic fungal species in both years. Across years, corn hybrids were more prone to infection by Aspergillus flavus Link (maximum isolation frequency = 8.8%) and Fusarium moniliforme Sheldon sensu lato (maximum isolation frequency = 72.8%), with corresponding greater concentrations of aflatoxins (maximum concentration = 204.9 microg kg(-1)) and fumonisins (maximum concentration = 34,039 microg kg(-1)). Pearl millet was more prone to infection by F. semitectum Berk. & Ravenel (maximum isolation = 74.2%) and F. chlamydosporum Wollenweb & Reinking (maximum isolation = 33.0%), and contamination by moniliformin (maximum contamination = 92.1 microg kg(-1)). Beauvericin (maximum concentration = 414.6 microg kg(-1)) was present in both hosts. Planting date of corn affected aflatoxin and beauvericin contamination in 2000, and fumonisin concentration in 2001. The observed differences in mycotoxin contamination of the grains, which are likely due to host-specific differences in susceptibility to pre-harvest mycoflora, may affect food safety when the crops are grown under stress conditions.

Fast and Efficient Stochastic Optimization for Analytic Continuation

DOE PAGES

Bao, Feng; Zhang, Guannan; Webster, Clayton G; ...

2016-09-28

In this analytic continuation of imaginary-time quantum Monte Carlo data to extract real-frequency spectra remains a key problem in connecting theory with experiment. Here we present a fast and efficient stochastic optimization method (FESOM) as a more accessible variant of the stochastic optimization method introduced by Mishchenko et al. [Phys. Rev. B 62, 6317 (2000)], and we benchmark the resulting spectra with those obtained by the standard maximum entropy method for three representative test cases, including data taken from studies of the two-dimensional Hubbard model. Genearally, we find that our FESOM approach yields spectra similar to the maximum entropy results.more » In particular, while the maximum entropy method yields superior results when the quality of the data is strong, we find that FESOM is able to resolve fine structure with more detail when the quality of the data is poor. In addition, because of its stochastic nature, the method provides detailed information on the frequency-dependent uncertainty of the resulting spectra, while the maximum entropy method does so only for the spectral weight integrated over a finite frequency region. Therefore, we believe that this variant of the stochastic optimization approach provides a viable alternative to the routinely used maximum entropy method, especially for data of poor quality.« less

Effect of improving the usability of an e-learning resource: a randomized trial.

PubMed

Davids, Mogamat Razeen; Chikte, Usuf M E; Halperin, Mitchell L

2014-06-01

Optimizing the usability of e-learning materials is necessary to reduce extraneous cognitive load and maximize their potential educational impact. However, this is often neglected, especially when time and other resources are limited. We conducted a randomized trial to investigate whether a usability evaluation of our multimedia e-learning resource, followed by fixing of all problems identified, would translate into improvements in usability parameters and learning by medical residents. Two iterations of our e-learning resource [version 1 (V1) and version 2 (V2)] were compared. V1 was the first fully functional version and V2 was the revised version after all identified usability problems were addressed. Residents in internal medicine and anesthesiology were randomly assigned to one of the versions. Usability was evaluated by having participants complete a user satisfaction questionnaire and by recording and analyzing their interactions with the application. The effect on learning was assessed by questions designed to test the retention and transfer of knowledge. Participants reported high levels of satisfaction with both versions, with good ratings on the System Usability Scale and adjective rating scale. In contrast, analysis of video recordings revealed significant differences in the occurrence of serious usability problems between the two versions, in particular in the interactive HandsOn case with its treatment simulation, where there was a median of five serious problem instances (range: 0-50) recorded per participant for V1 and zero instances (range: 0-1) for V2 (P < 0.001). There were no differences in tests of retention or transfer of knowledge between the two versions. In conclusion, usability evaluation followed by a redesign of our e-learning resource resulted in significant improvements in usability. This is likely to translate into improved motivation and willingness to engage with the learning material. In this population of relatively high-knowledge participants, learning scores were similar across the two versions. Copyright © 2014 The American Physiological Society.

Effect of improving the usability of an e-learning resource: a randomized trial

PubMed Central

Chikte, Usuf M. E.; Halperin, Mitchell L.

2014-01-01

Optimizing the usability of e-learning materials is necessary to reduce extraneous cognitive load and maximize their potential educational impact. However, this is often neglected, especially when time and other resources are limited. We conducted a randomized trial to investigate whether a usability evaluation of our multimedia e-learning resource, followed by fixing of all problems identified, would translate into improvements in usability parameters and learning by medical residents. Two iterations of our e-learning resource [version 1 (V1) and version 2 (V2)] were compared. V1 was the first fully functional version and V2 was the revised version after all identified usability problems were addressed. Residents in internal medicine and anesthesiology were randomly assigned to one of the versions. Usability was evaluated by having participants complete a user satisfaction questionnaire and by recording and analyzing their interactions with the application. The effect on learning was assessed by questions designed to test the retention and transfer of knowledge. Participants reported high levels of satisfaction with both versions, with good ratings on the System Usability Scale and adjective rating scale. In contrast, analysis of video recordings revealed significant differences in the occurrence of serious usability problems between the two versions, in particular in the interactive HandsOn case with its treatment simulation, where there was a median of five serious problem instances (range: 0–50) recorded per participant for V1 and zero instances (range: 0–1) for V2 (P < 0.001). There were no differences in tests of retention or transfer of knowledge between the two versions. In conclusion, usability evaluation followed by a redesign of our e-learning resource resulted in significant improvements in usability. This is likely to translate into improved motivation and willingness to engage with the learning material. In this population of relatively high-knowledge participants, learning scores were similar across the two versions. PMID:24913451

Designing Telemedicine Systems for Geriatric Patients: A Review of the Usability Studies.

PubMed

Narasimha, Shraddhaa; Madathil, Kapil Chalil; Agnisarman, Sruthy; Rogers, Hunter; Welch, Brandon; Ashok, Aparna; Nair, Aswathi; McElligott, James

2017-06-01

One area where telemedicine may prove to be highly effective is in providing medical care to the geriatric population, an age group predicted to account for 20% of the population in the near future. However, even though telemedicine has certain advantages, the usability of these systems with this population merits investigation. This article reviews the literature published from 2000 to 2016 with the goal of analyzing the characteristics of usability-related studies conducted using geriatric participants and the subsequent usability challenges identified. Articles were found using Web of Knowledge and PubMed citation indexing portals using the keywords (1) Telemedicine* AND Geriatrics* (2) Telemedicine* AND Usability* (3) Telemedicine* AND Usability* AND Older Adults*. A total of 297 articles were obtained from the initial search. After further detailed screening, 16 articles were selected for review based on the inclusion criteria. Of these, 60% of the studies focused on the overall usability of telemedicine systems; 6.25% focused on the usability of a telepresence robot; 12.5% compared a face-to-face medical consultation with the use of telemedicine systems, and 25% focused on the study of other aspects of telemedicine in addition to its usability. Findings reported in the studies included high patient satisfaction with telemedicine in 31.25%, whereas another 31.25% indicated a high acceptance of this method of medical consultation. Care coordination in 6.25% of the studies; confidence in telemedicine in 6.25%; trust, privacy, and reliability in 6.25%; and increased convenience when compared to personal visits in 18.75% were also reported. This review suggests limited research providing scientifically valid and reproducible usability evaluation at various stages of telemedicine system development. Telemedicine system designers need to consider the age-related issues in cognition, perception, and behavior of geriatric patients while designing telemedicine applications. Future directions for research were developed based on the limitations as well as other results found in this systematic review.

Effect of font size, italics, and colour count on web usability.

PubMed

Bhatia, Sanjiv K; Samal, Ashok; Rajan, Nithin; Kiviniemi, Marc T

2011-04-01

Web usability measures the ease of use of a website. This study attempts to find the effect of three factors - font size, italics, and colour count - on web usability. The study was performed using a set of tasks and developing a survey questionnaire. We performed the study using a set of human subjects, selected from the undergraduate students taking courses in psychology. The data computed from the tasks and survey questionnaire were statistically analysed to find if there was any effect of font size, italics, and colour count on the three web usability dimensions. We found that for the student population considered, there was no significant effect of font size on usability. However, the manipulation of italics and colour count did influence some aspects of usability. The subjects performed better for pages with no italics and high italics compared to moderate italics. The subjects rated the pages that contained only one colour higher than the web pages with four or six colours. This research will help web developers better understand the effect of font size, italics, and colour count on web usability in general, and for young adults, in particular.

Web usability testing with a Hispanic medically underserved population.

PubMed

Moore, Mary; Bias, Randolph G; Prentice, Katherine; Fletcher, Robin; Vaughn, Terry

2009-04-01

Skilled website developers value usability testing to assure user needs are met. When the target audience differs substantially from the developers, it becomes essential to tailor both design and evaluation methods. In this study, researchers carried out a multifaceted usability evaluation of a website (Healthy Texas) designed for Hispanic audiences with lower computer literacy and lower health literacy. METHODS INCLUDED: (1) heuristic evaluation by a usability engineer, (2) remote end-user testing using WebEx software; and (3) face-to-face testing in a community center where use of the website was likely. Researchers found standard usability testing methods needed to be modified to provide interpreters, increased flexibility for time on task, presence of a trusted intermediary such as a librarian, and accommodation for family members who accompanied participants. Participants offered recommendations for website redesign, including simplified language, engaging and relevant graphics, culturally relevant examples, and clear navigation. User-centered design is especially important when website developers are not representative of the target audience. Failure to conduct appropriate usability testing with a representative audience can substantially reduce use and value of the website. This thorough course of usability testing identified improvements that benefit all users but become crucial when trying to reach an underserved audience.

Mobile Health Applications, in the Absence of an Authentic Regulation, Does the Usability Score Correlate with a Better Medical Reliability?

PubMed

Yasini, Mobin; Marchand, Guillaume

2015-01-01

Health-related mobile applications (apps) have been shown to improve the quality of health and patient care. Their use in clinical and health-related environments is becoming more considerable. The number of health-related apps available for download has considerably increased, while the regulatory position of this new industry is not well known. Despite this lack of regulation, measuring the usability score of these apps is not difficult. We compared two samples of twenty health-related applications each. One of the samples contained the apps with top-rated usability scores, and the other contained the apps with lowest-rated usability scores. We found that a good usability score correlates with a better medical reliability of the app's content (p<0.005). In the period in which a valid regulation is still lacking, calculation and attribution of usability scores to mobile applications could be used to identify apps with better medical quality. However, the usability score method ought to be rigorous and should not be rounded off with a simple five stars rating (as is the case in the classic app stores).

Measuring the Usability of Augmented Reality e-Learning Systems: A User-Centered Evaluation Approach

NASA Astrophysics Data System (ADS)

Pribeanu, Costin; Balog, Alexandru; Iordache, Dragoş Daniel

The development of Augmented Reality (AR) systems is creating new challenges and opportunities for the designers of e-learning systems. The mix of real and virtual requires appropriate interaction techniques that have to be evaluated with users in order to avoid usability problems. Formative usability aims at finding usability problems as early as possible in the development life cycle and is suitable to support the development of such novel interactive systems. This work presents an approach to the user-centered usability evaluation of an e-learning scenario for Biology developed on an Augmented Reality educational platform. The evaluation has been carried on during and after a summer school held within the ARiSE research project. The basic idea was to perform usability evaluation twice. In this respect, we conducted user testing with a small number of students during the summer school in order to get a fast feedback from users having good knowledge in Biology. Then, we repeated the user testing in different conditions and with a relatively larger number of representative users. In this paper we describe both experiments and compare the usability evaluation results.

Effect of font size, italics, and colour count on web usability

PubMed Central

Samal, Ashok; Rajan, Nithin; Kiviniemi, Marc T.

2013-01-01

Web usability measures the ease of use of a website. This study attempts to find the effect of three factors – font size, italics, and colour count – on web usability. The study was performed using a set of tasks and developing a survey questionnaire. We performed the study using a set of human subjects, selected from the undergraduate students taking courses in psychology. The data computed from the tasks and survey questionnaire were statistically analysed to find if there was any effect of font size, italics, and colour count on the three web usability dimensions. We found that for the student population considered, there was no significant effect of font size on usability. However, the manipulation of italics and colour count did influence some aspects of usability. The subjects performed better for pages with no italics and high italics compared to moderate italics. The subjects rated the pages that contained only one colour higher than the web pages with four or six colours. This research will help web developers better understand the effect of font size, italics, and colour count on web usability in general, and for young adults, in particular. PMID:24358055

Effect of misspecification of gene frequency on the two-point LOD score.

PubMed

Pal, D K; Durner, M; Greenberg, D A

2001-11-01

In this study, we used computer simulation of simple and complex models to ask: (1) What is the penalty in evidence for linkage when the assumed gene frequency is far from the true gene frequency? (2) If the assumed model for gene frequency and inheritance are misspecified in the analysis, can this lead to a higher maximum LOD score than that obtained under the true parameters? Linkage data simulated under simple dominant, recessive, dominant and recessive with reduced penetrance, and additive models, were analysed assuming a single locus with both the correct and incorrect dominance model and assuming a range of different gene frequencies. We found that misspecifying the analysis gene frequency led to little penalty in maximum LOD score in all models examined, especially if the assumed gene frequency was lower than the generating one. Analysing linkage data assuming a gene frequency of the order of 0.01 for a dominant gene, and 0.1 for a recessive gene, appears to be a reasonable tactic in the majority of realistic situations because underestimating the gene frequency, even when the true gene frequency is high, leads to little penalty in the LOD score.

FREQUENCY CONTENT OF CARTILAGE IMPACT FORCE SIGNAL REFLECTS ACUTE HISTOLOGIC STRUCTURAL DAMAGE.

PubMed

Heiner, Anneliese D; Martin, James A; McKinley, Todd O; Goetz, Jessica E; Thedens, Daniel R; Brown, Thomas D

2012-10-01

The objective of this study was to determine if acute cartilage impact damage could be predicted by a quantification of the frequency content of the impact force signal. Osteochondral specimens excised from bovine lateral tibial plateaus were impacted with one of six impact energies. Each impact force signal underwent frequency analysis, with the amount of higher-frequency content (percent of frequency spectrum above 1 KHz) being registered. Specimens were histologically evaluated to assess acute structural damage (articular surface cracking and cartilage crushing) resulting from the impact. Acute histologic structural damage to the cartilage had higher concordance with the high-frequency content measure than with other mechanical impact measures (delivered impact energy, impact maximum stress, and impact maximum stress rate of change). This result suggests that the frequency content of an impact force signal, specifically the proportion of higher-frequency components, can be used as a quick surrogate measure for acute structural cartilage injury. Taking advantage of this relationship could reduce the time and expense of histological processing needed to morphologically assess cartilage damage, especially for purposes of initial screening when evaluating new impaction protocols.

The Effects of a Mobile Phone Application on Quality of Life in Patients With Type 1 Diabetes Mellitus: A Randomized Controlled Trial.

PubMed

Drion, Iefke; Pameijer, Loes R; van Dijk, Peter R; Groenier, Klaas H; Kleefstra, Nanne; Bilo, Henk J G

2015-05-11

The combination of an increasing prevalence of diabetes mellitus and more people having access to smartphones creates opportunities for patient care. This study aims to investigate whether the use of the Diabetes Under Control (DBEES) mobile phone application, a digital diabetes diary, results in a change in quality of life for patients with type 1 diabetes mellitus (T1DM) compared with the standard paper diary. In this randomized controlled open-label trial, 63 patients with T1DM having access to a smartphone were assigned to the intervention group using the DBEES application (n = 31) or the control group using the standard paper diary (n = 32). Primary outcome was the change in quality of life, as measured by the RAND-36 questionnaire, between both groups. Secondary outcomes included diabetes-related distress (PAID), HbA1c, frequency of self-monitoring blood glucose, and the usability of the diabetes application (SUS). Patients had a median age (IQR) of 33 (21) years, diabetes duration of 17 (16) years, and an HbA1c of 62 ± 16 mmol/mol. No significant differences in the QOL, using the RAND-36, within and between both groups were observed after 3 months. Glycemic control, diabetes-related emotional distress, and frequency of self-monitoring of blood glucose remained within and between groups. Users reviewed the usability of DBEES with a 72 ± 20, on a range of 0-100. The use of the DBEES application in the management of patients with T1DM for 3 months yields no alterations in quality of life compared to the standard paper diary. © 2015 Diabetes Technology Society.

Numerical Simulations of the XR-5 Hall Thruster for Life Assessment at Different Operating Conditions

NASA Technical Reports Server (NTRS)

Lopez Ortega, Alejandro; Jorns, Benjamin A.; Mikellides, Ioannis G.; Hofer, Richard R.

2015-01-01

NASA's Jet Propulsion Laboratory has been investigating the applicability of Aerojet Rocketdyne's XR-5 thruster, a 4.5 kW class Hall thruster, for deep-space missions. Major considerations for qualifying the XR-5 for deep-space missions are demonstration of a wide throttling envelope and a usable life capability in excess of 10,000 h. Numerical simulations with the 2-D axisymmetric code Hall2De are employed to inform the qualification process by assessing erosion rates at the thruster surfaces in a wide range of throttling conditions without the need for conducting costly endurance testing. In previous work at JPL by Jorns et al., the anomalous collision frequency distribution for 11 different throttling conditions of the XR-5 spanning 0.3-4.5 kW were identified based on probe measurements of the electron temperature in the near plume region. In this paper, we provide estimates for the erosion rates at the channel walls and pole covers for the same 11 conditions. Uncertainties in the plasma measurements and in the anomalous collision frequency distribution are addressed by determining upper and lower bounds of the erosion rates. Results suggest that erosion of the walls only occurs in the last 5% of the acceleration channel and the rate of such erosion decreases as the geometry of the thruster changes in time due to magnetic shielding. A quasi-zero-erosion state is eventually achieved in all the examined throttling conditions. Examination of the results for pole surface erosion and estimated cathode life indicates that the XR-5 propellant throughput capability will exceed 700 kg, which provides 50% margin over the usable throughput capability of 466 kg as already demonstrated in wear testing.

Streaming flow from ultrasound contrast agents by acoustic waves in a blood vessel model.

PubMed

Cho, Eunjin; Chung, Sang Kug; Rhee, Kyehan

2015-09-01

To elucidate the effects of streaming flow on ultrasound contrast agent (UCA)-assisted drug delivery, streaming velocity fields from sonicated UCA microbubbles were measured using particle image velocimetry (PIV) in a blood vessel model. At the beginning of ultrasound sonication, the UCA bubbles formed clusters and translated in the direction of the ultrasound field. Bubble cluster formation and translation were faster with 2.25MHz sonication, a frequency close to the resonance frequency of the UCA. Translation of bubble clusters induced streaming jet flow that impinged on the vessel wall, forming symmetric vortices. The maximum streaming velocity was about 60mm/s at 2.25MHz and decreased to 15mm/s at 1.0MHz for the same acoustic pressure amplitude. The effect of the ultrasound frequency on wall shear stress was more noticeable. Maximum wall shear stress decreased from 0.84 to 0.1Pa as the ultrasound frequency decreased from 2.25 to 1.0MHz. The maximum spatial gradient of the wall shear stress also decreased from 1.0 to 0.1Pa/mm. This study showed that streaming flow was induced by bubble cluster formation and translation and was stronger upon sonication by an acoustic wave with a frequency near the UCA resonance frequency. Therefore, the secondary radiant force, which is much stronger at the resonance frequency, should play an important role in UCA-assisted drug delivery. Copyright © 2015 Elsevier B.V. All rights reserved.

Neuromuscular fatigue and recovery dynamics following prolonged continuous run at anaerobic threshold.

PubMed

Skof, B; Strojnik, V

2006-03-01

The aim of this study was to determine the influence of intensive aerobic running on some muscle contractile characteristics and the dynamics of their recovery during a 2 hour period afterwards. Seven well trained runners performed a 6 km run at anaerobic threshold (V(OBLA)). Knee torque during single twitch, low and high frequency electrical stimulation (ES), maximum voluntary knee extension, and muscle activation level test of the quadriceps femoris muscles were measured before and immediately after the run, and at several time points during a 120 minute interval that followed the run. After exercise, the mean (SE) maximum twitch torque (T(TW)) and torque at ES with 20 Hz (low frequency ES; T(F20)) dropped by 14.1 (5.1)% (p<0.05) and 20.6 (7.9)% (p<0.05) respectively, while torque at stimulation with 100 Hz (high frequency ES; T(F100)), maximum isometric knee extension torque (maximum voluntary contraction torque; T(MVC)), and activation level did not change significantly. Twitch contraction time was shortened by 8 (2)% (p<0.05). Ten minutes after the run, T(TW) was 40% higher than immediately after the run and 10% (p<0.05) higher than before the run. T(F20), T(F100), and T(MVC) remained lower for 60 minutes (p<0.05) than before the run. A 6 km continuous run at V(OBLA) caused peripheral fatigue by impairing excitation-contraction coupling. Twitch torque recovered very quickly. However, the process of torque restoration at maximum isometric knee extension torque and at high and low frequency ES took much longer.

36 CFR 1193.21 - Accessibility, usability, and compatibility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Accessibility, usability, and compatibility. 1193.21 Section 1193.21 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION... Accessibility, usability, and compatibility. Where readily achievable, telecommunications equipment and customer...

36 CFR 1193.21 - Accessibility, usability, and compatibility.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Accessibility, usability, and compatibility. 1193.21 Section 1193.21 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION... Accessibility, usability, and compatibility. Where readily achievable, telecommunications equipment and customer...

36 CFR 1193.21 - Accessibility, usability, and compatibility.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Accessibility, usability, and compatibility. 1193.21 Section 1193.21 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION... Accessibility, usability, and compatibility. Where readily achievable, telecommunications equipment and customer...

36 CFR 1193.21 - Accessibility, usability, and compatibility.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Accessibility, usability, and compatibility. 1193.21 Section 1193.21 Parks, Forests, and Public Property ARCHITECTURAL AND TRANSPORTATION... Accessibility, usability, and compatibility. Where readily achievable, telecommunications equipment and customer...

Usability testing of a prototype multi-user telehealth kiosk.

PubMed

Courtney, Karen L; Matthews, Judith T; McMillan, Julie M; Person Mecca, Laurel; Smailagic, Asim; Siewiorek, Daniel

2015-01-01

The overall purpose of this study was to learn how community-dwelling older adults would interact with our prototype multi-user telehealth kiosk and their views about its usability. Seven subjects participated in laboratory-based usability sessions to evaluate the physical design, appearance, functionality and perceived ease of use of a multi-user telehealth kiosk prototype. During usability testing participants recommended 18 new features (29% of comments), identified 15 software errors (23% of comments) and 29 user interface errors (47% of comments).

Evaluation of the Dual-Chamber Pen Design for the Injection of Exenatide Once Weekly for the Treatment of Type 2 Diabetes

PubMed Central

LaRue, Susan; Malloy, Jaret

2015-01-01

Background: Exenatide once weekly, an injectable glucagon-like peptide-1 receptor agonist, has been shown to reduce A1C, fasting glucose, and body weight in patients with type 2 diabetes. Exenatide 2.0 mg is dispersed in poly-(D,L-lactide-co-glycolide) polymer microspheres, which require resuspension in aqueous diluent before subcutaneous injection. A single-use, dual-chamber pen was developed to improve the convenience of exenatide once weekly delivery and tested following Food and Drug Administration (FDA) guidance. Methods: Design development goals were established, and validation tests (dose accuracy, torque/force requirements, usability, and ease-of-use) were performed. Dose accuracy was tested under a variety of conditions. After 10 exploratory studies in 329 patients, the final design’s usability and ease-of-use were tested in untrained health care practitioners (HCPs; n = 16) and untrained/trained patients (n = 30/17). Usability testing evaluated completion of multiple setup, dose preparation, and injection steps. Ease-of-use impression was assessed using a scale of 1−7 (1 = very difficult, 7 = very easy). Results: The dual-chamber pen successfully met development goals and delivered target volume (650 µL ± 10%) under tested conditions (mean 644.7–649.3 µL), with torque and force requirements below prespecified maximum values. In the final user study, most participants (≥87%) correctly completed pen setup, dose preparation, and injection steps. Mean ease-of-use scores were 5.8, 6.3, and 6.5 out of 7 in untrained HCPs, untrained patients, and trained patients, respectively. Conclusion: With self-education or minimal training, participants accurately and precisely suspended, mixed, and delivered exenatide-containing microspheres using the dual-chamber pen with high ease-of-use scores. The dual-chamber pen was FDA-approved in February 2014. PMID:25759181

The McMaster Optimal Aging Portal: Usability Evaluation of a Unique Evidence-Based Health Information Website.

PubMed

Barbara, Angela M; Dobbins, Maureen; Haynes, R Brian; Iorio, Alfonso; Lavis, John N; Raina, Parminder; Levinson, Anthony J

2016-05-11

Increasingly, older adults and their informal caregivers are using the Internet to search for health-related information. There is a proliferation of health information online, but the quality of this information varies, often based on exaggerated or dramatic findings, and not easily comprehended by consumers. The McMaster Optimal Aging Portal (Portal) was developed to provide Internet users with high-quality evidence about aging and address some of these current limitations of health information posted online. The Portal includes content for health professionals coming from three best-in-class resources (MacPLUS, Health Evidence, and Health Systems Evidence) and four types of content specifically prepared for the general public (Evidence Summaries, Web Resource Ratings, Blog Posts, and Twitter messages). Our objectives were to share the findings of the usability evaluation of the Portal with particular focus on the content features for the general public and to inform designers of health information websites and online resources for older adults about key usability themes. Data analysis included task performance during usability testing and qualitative content analyses of both the usability sessions and interviews to identify core themes. A total of 37 participants took part in 33 usability testing sessions and 21 focused interviews. Qualitative analysis revealed common themes regarding the Portal's strengths and challenges to usability. The strengths of the website were related to credibility, applicability, browsing function, design, and accessibility. The usability challenges included reluctance to register, process of registering, searching, terminology, and technical features. The study reinforced the importance of including end users during the development of this unique, dynamic, evidence-based health information website. The feedback was applied to iteratively improve website usability. Our findings can be applied by designers of health-related websites.

The McMaster Optimal Aging Portal: Usability Evaluation of a Unique Evidence-Based Health Information Website

PubMed Central

Dobbins, Maureen; Haynes, R. Brian; Iorio, Alfonso; Lavis, John N; Raina, Parminder

2016-01-01

Background Increasingly, older adults and their informal caregivers are using the Internet to search for health-related information. There is a proliferation of health information online, but the quality of this information varies, often based on exaggerated or dramatic findings, and not easily comprehended by consumers. The McMaster Optimal Aging Portal (Portal) was developed to provide Internet users with high-quality evidence about aging and address some of these current limitations of health information posted online. The Portal includes content for health professionals coming from three best-in-class resources (MacPLUS, Health Evidence, and Health Systems Evidence) and four types of content specifically prepared for the general public (Evidence Summaries, Web Resource Ratings, Blog Posts, and Twitter messages). Objective Our objectives were to share the findings of the usability evaluation of the Portal with particular focus on the content features for the general public and to inform designers of health information websites and online resources for older adults about key usability themes. Methods Data analysis included task performance during usability testing and qualitative content analyses of both the usability sessions and interviews to identify core themes. Results A total of 37 participants took part in 33 usability testing sessions and 21 focused interviews. Qualitative analysis revealed common themes regarding the Portal’s strengths and challenges to usability. The strengths of the website were related to credibility, applicability, browsing function, design, and accessibility. The usability challenges included reluctance to register, process of registering, searching, terminology, and technical features. Conclusions The study reinforced the importance of including end users during the development of this unique, dynamic, evidence-based health information website. The feedback was applied to iteratively improve website usability. Our findings can be applied by designers of health-related websites. PMID:27170443

Detection of main tidal frequencies using least squares harmonic estimation method

NASA Astrophysics Data System (ADS)

Mousavian, R.; Hossainali, M. Mashhadi

2012-11-01

In this paper the efficiency of the method of Least Squares Harmonic Estimation (LS-HE) for detecting the main tidal frequencies is investigated. Using this method, the tidal spectrum of the sea level data is evaluated at two tidal stations: Bandar Abbas in south of Iran and Workington on the eastern coast of the UK. The amplitudes of the tidal constituents at these two tidal stations are not the same. Moreover, in contrary to the Workington station, the Bandar Abbas tidal record is not an equispaced time series. Therefore, the analysis of the hourly tidal observations in Bandar Abbas and Workington can provide a reasonable insight into the efficiency of this method for analyzing the frequency content of tidal time series. Furthermore, applying the method of Fourier transform to the Workington tidal record provides an independent source of information for evaluating the tidal spectrum proposed by the LS-HE method. According to the obtained results, the spectrums of these two tidal records contain the components with the maximum amplitudes among the expected ones in this time span and some new frequencies in the list of known constituents. In addition, in terms of frequencies with maximum amplitude; the power spectrums derived from two aforementioned methods are the same. These results demonstrate the ability of LS-HE for identifying the frequencies with maximum amplitude in both tidal records.

Usability of a New Writing Assistive Device for Persons with Cervical Spinal Cord Injury.

PubMed

Lim, MyungJoon; Park, Jiyoung; Lee, Kuem Ju; Kweon, Hyosun; Kim, Byungchul; Cho, Kyujin; Choi, Hyun

2015-01-01

The hand function for persons with cervical spinal cord injury (PCSCI) is most frequently cause difficulties in leading normal lives. The purpose of this study was to test the usability of a new writing assistive device (NWAD) for PCSCI. To access its usability, the authors design usability testing method and test the NWAD to five individuals with cervical spinal cord injury. From the usability testing, we have found number of issues that lead us to key design concept about developing the NWAD. The NWAD will be redesigned based on the result of the present study. We expect that the NWAD will help PCSCI use their affected hand better and improve the level of independence and quality of life.

A physiological frequency-position map of the chinchilla cochlea.

PubMed

Müller, Marcus; Hoidis, Silvi; Smolders, Jean W T

2010-09-01

Accumulating evidence indicates that mammalian cochlear frequency-position maps (location of maximum vibration of the basilar membrane as a function of frequency) depend on the physiological condition of the inner ear. Cochlear damage desensitizes the ear, after the damage the original location of maximum vibration is tuned to a lower sound frequency. This suggests that frequency-position maps, derived from such desensitized ears, are shifted to lower frequencies, corresponding to a shift of the basilar membrane vibration pattern towards the base for a given stimulus frequency. To test this hypothesis, we re-mapped the cochlear frequency-position map in the chinchilla. We collected frequency-position data from chinchillas in normal physiological condition ("physiological map") and compared these to data previously established from sound overexposed ears ("anatomical map"). The characteristic frequency (CF) of neurons in the cochlear nucleus was determined. Horse-radish peroxidase (HRP) or biocytin (BCT) were injected iontophoretically to trace auditory nerve fibers towards their innervation site in the organ of Corti. The relationship between distance from the base (d, percent) and frequency (f, kHz) was described best by a simple exponential function: d = 61.2 - 42.2 x log(f). The slope of the function was 2.55 mm/octave. Compared to the "anatomical map", the "physiological map" was shifted by about 0.3 octaves to higher frequencies corresponding to a shift of the basilar membrane vibration pattern of 0.8 mm towards the apex for a given stimulus frequency. Our findings affirm that frequency-position maps in the mammalian cochlea depend on the condition of the inner ear. Damage-induced desensitization in mammalian inner ears results in similar shifts of CF (about 0.5 octaves) but different shifts of the maximum of the vibration pattern towards the base at given frequencies, dependent on the mapping constant of the species, longer basilar membranes showing a larger basal shift. Furthermore, the results substantiate the notion that "crowding" at lower frequencies appears to be a specialization rather than a general feature. Copyright (c) 2010 Elsevier B.V. All rights reserved.

A Usability Case Study Using TREC and ZPRISE.

ERIC Educational Resources Information Center

Downey, Laura L.; Tice, Dawn M.

1999-01-01

Examines the challenges involved in conducting an informal usability case study based on the introduction of a new information-retrieval system to experienced users. Identifies problems users were having with TREC (Text Retrieval Conference) and examines the usability of the new ZPRISE interface. (Author/LRW)

7 CFR 42.102 - Definitions, general.

Code of Federal Regulations, 2014 CFR

2014-01-01

... the serviceability, including appearance as well as usability, of the container for its intended.... A defect that seriously affects, or is likely to seriously affect, the usability of the container... materially affect, the usability of the container for its intended purpose. (c) Minor defect. A defect that...

Dimensions for hearing-impaired mobile application usability model

NASA Astrophysics Data System (ADS)

Nathan, Shelena Soosay; Hussain, Azham; Hashim, Nor Laily; Omar, Mohd Adan

2017-10-01

This paper discuss on the dimensions that has been derived for the hearing-impaired mobile applications usability model. General usability model consist of general dimension for evaluating mobile application however requirements for the hearing-impaired are overlooked and often scanted. This led towards mobile application developed for the hearing-impaired are left unused. It is also apparent that these usability models do not consider accessibility dimensions according to the requirement of the special users. This complicates the work of usability practitioners as well as academician that practices research usability when application are developed for the specific user needs. To overcome this issue, dimension chosen for the hearing-impaired are ensured to be align with the real need of the hearing-impaired mobile application. Besides literature studies, requirements for the hearing-impaired mobile application have been identified through interview conducted with hearing-impaired mobile application users that were recorded as video outputs and analyzed using Nvivo. Finally total of 6 out of 15 dimensions gathered are chosen for the proposed model and presented.

Developing Analytical Inspection Criteria for Health IT Personnel with Minimum Training in Cognitive Ergonomics: A Practical Solution to EHR Improving EHR Usability

PubMed Central

Zhang, Zhen; Franklin, Amy; Walji, Muhammad; Zhang, Jiajie; Gong, Yang

2014-01-01

EHR usability has been identified as a major barrier to care quality optimization. One major challenge of improving EHR usability is the lack of systematic training in usability or cognitive ergonomics for EHR designers/developers in the vendor community and EHR analysts making significant configurations in healthcare organizations. A practical solution is to provide usability inspection tools that can be easily operationalized by EHR analysts. This project is aimed at developing a set of usability tools with demonstrated validity and reliability. We present a preliminary study of a metric for cognitive transparency and an exploratory experiment testing its validity in predicting the effectiveness of action-effect mapping. Despite the pilot nature of both, we found high sensitivity and specificity of the metric and higher response accuracy within a shorter time for users to determine action-effect mappings in transparent user interface controls. We plan to expand the sample size in our empirical study. PMID:25954439

Usability and acceptability of balance exergames in older adults: A scoping review.

PubMed

Nawaz, Ather; Skjæret, Nina; Helbostad, Jorunn Lægdheim; Vereijken, Beatrix; Boulton, Elisabeth; Svanaes, Dag

2016-12-01

Serious games (exergames) have the potential to be effective for postural balance and increasing muscle strength. Several games have been developed to increase physical fitness and balance among older adults. However, it is unclear to which degree usability and acceptability of exergames for older adults have been evaluated. The aim of this study was to summarize usability evaluation and acceptability of studies in older adults. We conducted a scoping review on studies focusing on usability of exergames for older adults. The result shows that older adults consider usability and acceptability of exercise video games good. The review shows that longitudinal studies mainly use off-the-shelf exergame and evaluated game effectiveness and acceptability, whereas cross-sectional studies focus on interactional experience. Studies varied in their approaches to measure usability and acceptability of exergames for older adults. There is a need for a systematic developmental approach to involve older adults in development of exergames for longitudinal studies. © The Author(s) 2015.

A usability evaluation toolkit for In-Vehicle Information Systems (IVISs).

PubMed

Harvey, Catherine; Stanton, Neville A; Pickering, Carl A; McDonald, Mike; Zheng, Pengjun

2011-05-01

Usability must be defined specifically for the context of use of the particular system under investigation. This specific context of use should also be used to guide the definition of specific usability criteria and the selection of appropriate evaluation methods. There are four principles which can guide the selection of evaluation methods, relating to the information required in the evaluation, the stage at which to apply methods, the resources required and the people involved in the evaluation. This paper presents a framework for the evaluation of usability in the context of In-Vehicle Information Systems (IVISs). This framework guides designers through defining usability criteria for an evaluation, selecting appropriate evaluation methods and applying those methods. These stages form an iterative process of design-evaluation-redesign with the overall aim of improving the usability of IVISs and enhancing the driving experience, without compromising the safety of the driver. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Usability and Culture as Two of the Value Criteria for Evaluating the Artifact

NASA Astrophysics Data System (ADS)

Kurosu, Masaaki

In this paper, the conceptual framework of the Artifact Development Analysis (ADA) and its relationship to the usability engineering are outlined. The ADA analyses the significance of all artifacts including hardware, software, humanware and system. Its viewpoint extends both in temporal and spatial dimensions. In short, it deals with the diversity of the artifact and casts the questions "why it is so" and "why it is not so". In this respect, the ADA is related to the usability engineering as one of the value attitudes. The usability engineering puts emphasis on effectiveness and efficiency. The usability is not always the value criterion of highest importance and some people sometimes put more emphasis on other criteria such as the aesthetic aspect, the cost, etc. Based on the findings of ADA, we should focus on the extent where the usability can provide the core satisfaction and we should also summarize the guideline on how the artifact should be designed.

A Method for Automated Detection of Usability Problems from Client User Interface Events

PubMed Central

Saadawi, Gilan M.; Legowski, Elizabeth; Medvedeva, Olga; Chavan, Girish; Crowley, Rebecca S.

2005-01-01

Think-aloud usability analysis provides extremely useful data but is very time-consuming and expensive to perform because of the extensive manual video analysis that is required. We describe a simple method for automated detection of usability problems from client user interface events for a developing medical intelligent tutoring system. The method incorporates (1) an agent-based method for communication that funnels all interface events and system responses to a centralized database, (2) a simple schema for representing interface events and higher order subgoals, and (3) an algorithm that reproduces the criteria used for manual coding of usability problems. A correction factor was empirically determining to account for the slower task performance of users when thinking aloud. We tested the validity of the method by simultaneously identifying usability problems using TAU and manually computing them from stored interface event data using the proposed algorithm. All usability problems that did not rely on verbal utterances were detectable with the proposed method. PMID:16779121

Situated Usability Testing for Security Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greitzer, Frank L.

2011-03-02

While usability testing is well established, assessing the usability of security software, tools, or methods deserves more careful consideration. It has been argued that dealing with security has become too difficult for individuals or organizations to manage effectively or to use conveniently. As difficult as it is for system administrators and developers to deal with, security is even more challenging for casual users. Indeed, it is much too easy for casual/home users to configure the security of their systems in non-optimal ways that leave their systems inadvertently insecure. This is exacerbated by the fact that casual users are focused onmore » matters other than security, and likely would prefer not even to think about security. This brief report argues that when security and/or privacy are part of the equation, traditional methods for usability testing should be re-considered. The purpose of this brief report is to argue for and outline a method associated with a new approach to usability testing for examining usable security issues.« less

Usability in product design--the importance and need for systematic assessment models in product development--Usa-Design Model (U-D) ©.

PubMed

Merino, Giselle Schmidt Alves Díaz; Teixeira, Clarissa Stefani; Schoenardie, Rodrigo Petry; Merino, Eugenio Andrés Diáz; Gontijo, Leila Amaral

2012-01-01

In product design, human factors are considered as an element of differentiation given that today's consumer demands are increasing. Safety, wellbeing, satisfaction, health, effectiveness, efficiency, and other aspects must be effectively incorporated into the product development process. This work proposes a usability assessment model that can be incorporated as an assessment tool. The methodological approach is settled in two stages. First a literature review focus specifically on usability and developing user-centred products. After this, a model of usability named Usa-Design (U-D©) is presented. Consisted of four phases: understanding the use context, pre-preliminary usability assessment (efficiency/effectiveness/satisfaction); assessment of usability principles and results, U-D© features are modular and flexible, allowing principles used in Phase 3 to be changed according to the needs and scenario of each situation. With qualitative/quantitative measurement scales of easy understanding and application, the model results are viable and applicable throughout all the product development process.

Relationship Between Frequency and Deflection Angle in the DNA Prism

PubMed Central

Chen, Zhen; Dorfman, Kevin D.

2013-01-01

The DNA prism is a modification of the standard pulsed-field electrophoresis protocol to provide a continuous separation, where the DNA are deflected at an angle that depends on their molecular weight. The standard switchback model for the DNA prism predicts a monotonic increase in the deflection angle as a function of the frequency for switching the field until a plateau regime is reached. However, experiments indicate that the deflection angle achieves a maximum value before decaying to a size-independent value at high frequencies. Using Brownian dynamics simulations, we show that the maximum in the deflection angle is related to the reorientation time for the DNA and the decay in deflection angle at high frequencies is due to inadequate stretching. The generic features of the dependence of the deflection angle on molecular weight, switching frequency, and electric field strength explain a number of experimental phenomena. PMID:23410375

Usability Assessment of the Missouri Cancer Registry's Published Interactive Mapping Reports: Round One.

PubMed

Ben Ramadan, Awatef Ahmed; Jackson-Thompson, Jeannette; Schmaltz, Chester Lee

2017-08-04

 Many users of spatial data have difficulty interpreting information in health-related spatial reports. The Missouri Cancer Registry and Research Center (MCR-ARC) has produced interactive reports for several years. These reports have never been tested for usability.  The aims of this study were to: (1) conduct a multi-approach usability testing study to understand ease of use (user friendliness) and user satisfaction; and (2) evaluate the usability of MCR-ARC's published InstantAtlas reports.   An institutional review board (IRB) approved mixed methodology usability testing study using a convenience sample of health professionals. A recruiting email was sent to faculty in the Master of Public Health program and to faculty and staff in the Department of Health Management and Informatics at the University of Missouri-Columbia. The study included 7 participants. The test included a pretest questionnaire, a multi-task usability test, and the System Usability Scale (SUS). Also, the researchers collected participants' comments about the tested maps immediately after every trial. Software was used to record the computer screen during the trial and the participants' spoken comments. Several performance and usability metrics were measured to evaluate the usability of MCR-ARC's published mapping reports. Of the 10 assigned tasks, 6 reached a 100% completion success rate, and this outcome was relative to the complexity of the tasks. The simple tasks were handled more efficiently than the complicated tasks. The SUS score ranged between 20-100 points, with an average of 62.7 points and a median of 50.5 points. The tested maps' effectiveness outcomes were better than the efficiency and satisfaction outcomes. There was a statistically significant relationship between the subjects' performance on the study test and the users' previous experience with geographic information system (GIS) tools (P=.03). There were no statistically significant relationships between users' performance and satisfaction and their education level, work type, or previous experience in health care (P>.05). There were strong positive correlations between the three measured usability elements. The tested maps should undergo an extensive refining and updating to overcome all the discovered usability issues and meet the perspectives and needs of the tested maps' potential users. The study results might convey the perspectives of academic health professionals toward GIS health data. We need to conduct a second-round usability study with public health practitioners and cancer professionals who use GIS tools on a routine basis. Usability testing should be conducted before and after releasing MCR-ARC's maps in the future. ©Awatef Ahmed Ben Ramadan, Jeannette Jackson-Thompson, Chester Lee Schmaltz. Originally published in JMIR Human Factors (http://humanfactors.jmir.org), 04.08.2017.

Usability Assessment of the Missouri Cancer Registry’s Published Interactive Mapping Reports: Round One

PubMed Central

Jackson-Thompson, Jeannette; Schmaltz, Chester Lee

2017-01-01

Background  Many users of spatial data have difficulty interpreting information in health-related spatial reports. The Missouri Cancer Registry and Research Center (MCR-ARC) has produced interactive reports for several years. These reports have never been tested for usability. Objective  The aims of this study were to: (1) conduct a multi-approach usability testing study to understand ease of use (user friendliness) and user satisfaction; and (2) evaluate the usability of MCR-ARC’s published InstantAtlas reports. Methods   An institutional review board (IRB) approved mixed methodology usability testing study using a convenience sample of health professionals. A recruiting email was sent to faculty in the Master of Public Health program and to faculty and staff in the Department of Health Management and Informatics at the University of Missouri-Columbia. The study included 7 participants. The test included a pretest questionnaire, a multi-task usability test, and the System Usability Scale (SUS). Also, the researchers collected participants’ comments about the tested maps immediately after every trial. Software was used to record the computer screen during the trial and the participants’ spoken comments. Several performance and usability metrics were measured to evaluate the usability of MCR-ARC’s published mapping reports. Results Of the 10 assigned tasks, 6 reached a 100% completion success rate, and this outcome was relative to the complexity of the tasks. The simple tasks were handled more efficiently than the complicated tasks. The SUS score ranged between 20-100 points, with an average of 62.7 points and a median of 50.5 points. The tested maps’ effectiveness outcomes were better than the efficiency and satisfaction outcomes. There was a statistically significant relationship between the subjects’ performance on the study test and the users’ previous experience with geographic information system (GIS) tools (P=.03). There were no statistically significant relationships between users’ performance and satisfaction and their education level, work type, or previous experience in health care (P>.05). There were strong positive correlations between the three measured usability elements. Conclusions The tested maps should undergo an extensive refining and updating to overcome all the discovered usability issues and meet the perspectives and needs of the tested maps’ potential users. The study results might convey the perspectives of academic health professionals toward GIS health data. We need to conduct a second-round usability study with public health practitioners and cancer professionals who use GIS tools on a routine basis. Usability testing should be conducted before and after releasing MCR-ARC’s maps in the future. PMID:28778842

Multi-factor evaluation indicator method for the risk assessment of atmospheric and oceanic hazard group due to the attack of tropical cyclones

NASA Astrophysics Data System (ADS)

Qi, Peng; Du, Mei

2018-06-01

China's southeast coastal areas frequently suffer from storm surge due to the attack of tropical cyclones (TCs) every year. Hazards induced by TCs are complex, such as strong wind, huge waves, storm surge, heavy rain, floods, and so on. The atmospheric and oceanic hazards cause serious disasters and substantial economic losses. This paper, from the perspective of hazard group, sets up a multi-factor evaluation method for the risk assessment of TC hazards using historical extreme data of concerned atmospheric and oceanic elements. Based on the natural hazard dynamic process, the multi-factor indicator system is composed of nine natural hazard factors representing intensity and frequency, respectively. Contributing to the indicator system, in order of importance, are maximum wind speed by TCs, attack frequency of TCs, maximum surge height, maximum wave height, frequency of gusts ≥ Scale 8, rainstorm intensity, maximum tidal range, rainstorm frequency, then sea-level rising rate. The first four factors are the most important, whose weights exceed 10% in the indicator system. With normalization processing, all the single-hazard factors are superposed by multiplying their weights to generate a superposed TC hazard. The multi-factor evaluation indicator method was applied to the risk assessment of typhoon-induced atmospheric and oceanic hazard group in typhoon-prone southeast coastal cities of China.

Dynamic impedance compensation for wireless power transfer using conjugate power

NASA Astrophysics Data System (ADS)

Liu, Suqi; Tan, Jianping; Wen, Xue

2018-02-01

Wireless power transfer (WPT) via coupled magnetic resonances has been in development for over a decade. However, the frequency splitting phenomenon occurs in the over-coupled region. Thus, the output power of the two-coil system achieves the maximum output power at the two splitting angular frequencies, and not at the natural resonant angular frequency. According to the maximum power transfer theorem, the impedance compensation method was adopted in many WPT projects. However, it remains a challenge to achieve the maximum output power and transmission efficiency in a fixed-frequency mode. In this study, dynamic impedance compensation for WPT was presented by utilizing the compensator within a virtual three-coil WPT system. First, the circuit model was established and transfer characteristics of a system were studied by utilizing circuit theories. Second, the power superposition of the WPT system was carefully researched. When a pair of compensating coils was inserted into the transmitter loop, the conjugate power of the compensator loop was created via magnetic coupling of the two compensating coils that insert into the transmitter loop. The mechanism for dynamic impedance compensation for wireless power transfer was then provided by investigating a virtual three-coil WPT system. Finally, the experimental circuit of a virtual three-coil WPT system was designed, and experimental results are consistent with the theoretical analysis, which achieves the maximum output power and transmission efficiency.

Continuity vs. the Crowd-Tradeoffs Between Continuous and Intermittent Citizen Hydrology Streamflow Observations.

PubMed

Davids, Jeffrey C; van de Giesen, Nick; Rutten, Martine

2017-07-01

Hydrologic data has traditionally been collected with permanent installations of sophisticated and accurate but expensive monitoring equipment at limited numbers of sites. Consequently, observation frequency and costs are high, but spatial coverage of the data is limited. Citizen Hydrology can possibly overcome these challenges by leveraging easily scaled mobile technology and local residents to collect hydrologic data at many sites. However, understanding of how decreased observational frequency impacts the accuracy of key streamflow statistics such as minimum flow, maximum flow, and runoff is limited. To evaluate this impact, we randomly selected 50 active United States Geological Survey streamflow gauges in California. We used 7 years of historical 15-min flow data from 2008 to 2014 to develop minimum flow, maximum flow, and runoff values for each gauge. To mimic lower frequency Citizen Hydrology observations, we developed a bootstrap randomized subsampling with replacement procedure. We calculated the same statistics, and their respective distributions, from 50 subsample iterations with four different subsampling frequencies ranging from daily to monthly. Minimum flows were estimated within 10% for half of the subsample iterations at 39 (daily) and 23 (monthly) of the 50 sites. However, maximum flows were estimated within 10% at only 7 (daily) and 0 (monthly) sites. Runoff volumes were estimated within 10% for half of the iterations at 44 (daily) and 12 (monthly) sites. Watershed flashiness most strongly impacted accuracy of minimum flow, maximum flow, and runoff estimates from subsampled data. Depending on the questions being asked, lower frequency Citizen Hydrology observations can provide useful hydrologic information.

Sound absorption study on acoustic panel from kapok fiber and egg tray

NASA Astrophysics Data System (ADS)

Kaamin, Masiri; Mahir, Nurul Syazwani Mohd; Kadir, Aslila Abd; Hamid, Nor Baizura; Mokhtar, Mardiha; Ngadiman, Norhayati

2017-12-01

Noise also known as a sound, especially one that is loud or unpleasant or that causes disruption. The level of noise can be reduced by using sound absorption panel. Currently, the market produces sound absorption panel, which use synthetic fibers that can cause harmful effects to the health of consumers. An awareness of using natural fibers from natural materials gets attention of some parties to use it as a sound absorbing material. Therefore, this study was conducted to investigate the potential of sound absorption panel using egg trays and kapok fibers. The test involved in this study was impedance tube test which aims to get sound absorption coefficient (SAC). The results showed that there was good sound absorption at low frequency from 0 Hz up to 900 Hz where the maximum absorption coefficient was 0.950 while the maximum absorption at high frequencies was 0.799. Through the noise reduction coefficient (NRC), the material produced NRC of 0.57 indicates that the materials are very absorbing. In addition, the reverberation room test was carried out to get the value of reverberation time (RT) in unit seconds. Overall this panel showed good results at low frequencies between 0 Hz up to 1500 Hz. In that range of frequency, the maximum reverberation time for the panel was 3.784 seconds compared to the maximum reverberation time for an empty room was 5.798 seconds. This study indicated that kapok fiber and egg tray as the material of absorption panel has a potential as environmental and cheap products in absorbing sound at low frequency.

An increased rectal maximum tolerable volume and long anal canal are associated with poor short-term response to biofeedback therapy for patients with anismus with decreased bowel frequency and normal colonic transit time.

PubMed

Rhee, P L; Choi, M S; Kim, Y H; Son, H J; Kim, J J; Koh, K C; Paik, S W; Rhee, J C; Choi, K W

2000-10-01

Biofeedback is an effective therapy for a majority of patients with anismus. However, a significant proportion of patients still failed to respond to biofeedback, and little has been known about the factors that predict response to biofeedback. We evaluated the factors associated with poor response to biofeedback. Biofeedback therapy was offered to 45 patients with anismus with decreased bowel frequency (less than three times per week) and normal colonic transit time. Any differences in demographics, symptoms, and parameters of anorectal physiologic tests were sought between responders (in whom bowel frequency increased up to three times or more per week after biofeedback) and nonresponders (in whom bowel frequency remained less than three times per week). Thirty-one patients (68.9 percent) responded to biofeedback and 14 patients (31.1 percent) did not. Anal canal length was longer in nonresponders than in responders (4.53 +/- 0.5 vs. 4.08 +/- 0.56 cm; P = 0.02), and rectal maximum tolerable volume was larger in nonresponders than in responders. (361 +/- 87 vs. 302 +/- 69 ml; P = 0.02). Anal canal length and rectal maximum tolerable volume showed significant differences between responders and nonresponders on multivariate analysis (P = 0.027 and P = 0.034, respectively). This study showed that a long anal canal and increased rectal maximum tolerable volume are associated with poor short-term response to biofeedback for patients with anismus with decreased bowel frequency and normal colonic transit time.

Polarized components of C=O vibrations Raman spectra for ethylacetate, acetone, and aggregation of molecules

NASA Astrophysics Data System (ADS)

Tukhvatullin, F. H.; Jumabaev, A.; Tashkenbaev, U. N.; Hushvaktov, H. A.; Absanov, A. A.

2002-11-01

For liquid ethylacetate the frequency maximums for parallel (I|| (v)) and perpendicular (I\\highmod(v)) polarized components of C=O vibrations band in Raman spectra are differed on 5.3 cm-1. At dilution ethylacetate in CCl4 and heptane or heating in this difference is decreased by displacement of I|| (v) maximum to the I\\highmod(v) maximum. In polar solvent, nitrometane, the picture is different - the frequency maxima difference is decreased though the displacement of I\\highmod(v) band maximum to the I|| (v)one. The results were explained by the complexity of C=O vibration bands, and existence within the band of two lines with the different depolarization ratio. The complexity of the band is the result existence in liquid ethylacetate the monomer molecules and molecular aggregations.

Laser plasma instability experiments with KrF lasersa)

NASA Astrophysics Data System (ADS)

Weaver, J. L.; Oh, J.; Afeyan, B.; Phillips, L.; Seely, J.; Feldman, U.; Brown, C.; Karasik, M.; Serlin, V.; Aglitskiy, Y.; Mostovych, A. N.; Holland, G.; Obenschain, S.; Chan, L.-Y.; Kehne, D.; Lehmberg, R. H.; Schmitt, A. J.; Colombant, D.; Velikovich, A.

2007-05-01

Deleterious effects of laser-plasma instability (LPI) may limit the maximum laser irradiation that can be used for inertial confinement fusion. The short wavelength (248nm), large bandwidth, and very uniform illumination available with krypton-fluoride (KrF) lasers should increase the maximum usable intensity by suppressing LPI. The concomitant increase in ablation pressure would allow implosion of low-aspect-ratio pellets to ignition with substantial gain (>20) at much reduced laser energy. The proposed KrF-laser-based Fusion Test Facility (FTF) would exploit this strategy to achieve significant fusion power (150MW) with a rep-rate system that has a per pulse laser energy well below 1 MJ. Measurements of LPI using the Nike KrF laser are presented at and above intensities needed for the FTF (I˜2×1015W/cm2). The results to date indicate that LPI is indeed suppressed. With overlapped beam intensity above the planar, single beam intensity threshold for the two-plasmon decay instability, no evidence of instability was observed via measurements of 3/2ωo and 1/2ωo harmonic emissions.

Temperature distributions and thermal stresses in a graded zirconia/metal gas path seal system for aircraft gas turbine engines

NASA Technical Reports Server (NTRS)

Taylor, C. M.; Bill, R. C.

1978-01-01

A ceramic/metallic aircraft gas turbine outer gas path seal designed for improved engine performance was studied. Transient temperature and stress profiles in a test seal geometry were determined by numerical analysis. During a simulated engine deceleration cycle from sea-level takeoff to idle conditions, the maximum seal temperature occurred below the seal surface, therefore the top layer of the seal was probably subjected to tensile stresses exceeding the modulus of rupture. In the stress analysis both two- and three-dimensional finite element computer programs were used. Predicted trends of the simpler and more easily usable two-dimensional element programs were borne out by the three-dimensional finite element program results.

7 CFR 42.102 - Definitions, general.

Code of Federal Regulations, 2011 CFR

2011-01-01

... freedom from defects which affect the serviceability, including appearance as well as usability, of the..., the usability of the container for its intended purpose. (b) Major defect. A defect that materially affects, or is likely to materially affect, the usability of the container for its intended purpose. (c...

Evaluating Web Usability

ERIC Educational Resources Information Center

Snider, Jean; Martin, Florence

2012-01-01

Web usability focuses on design elements and processes that make web pages easy to use. A website for college students was evaluated for underutilization. One-on-one testing, focus groups, web analytics, peer university review and marketing focus group and demographic data were utilized to conduct usability evaluation. The results indicated that…

Using participative inquiry in usability analysis to align a development team's mental model with its users' needs

NASA Technical Reports Server (NTRS)

Kneifel, A. A.; Guerrero, C.

2003-01-01

In this web site usability case study, two methods of participative inquiry are used to align a development team's objectives with their users' needs and to promote the team awareness of the benefit of qualitative usability analysis.

7 CFR 42.102 - Definitions, general.

Code of Federal Regulations, 2013 CFR

2013-01-01

... freedom from defects which affect the serviceability, including appearance as well as usability, of the..., the usability of the container for its intended purpose. (b) Major defect. A defect that materially affects, or is likely to materially affect, the usability of the container for its intended purpose. (c...

7 CFR 42.102 - Definitions, general.

Code of Federal Regulations, 2012 CFR

2012-01-01

... freedom from defects which affect the serviceability, including appearance as well as usability, of the..., the usability of the container for its intended purpose. (b) Major defect. A defect that materially affects, or is likely to materially affect, the usability of the container for its intended purpose. (c...

36 CFR § 1193.21 - Accessibility, usability, and compatibility.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Accessibility, usability, and compatibility. § 1193.21 Section § 1193.21 Parks, Forests, and Public Property ARCHITECTURAL AND... § 1193.21 Accessibility, usability, and compatibility. Where readily achievable, telecommunications...

Automatic Modulation Classification of Common Communication and Pulse Compression Radar Waveforms using Cyclic Features

DTIC Science & Technology

2013-03-01

intermediate frequency LFM linear frequency modulation MAP maximum a posteriori MATLAB® matrix laboratory ML maximun likelihood OFDM orthogonal frequency...spectrum, frequency hopping, and orthogonal frequency division multiplexing ( OFDM ) modulations. Feature analysis would be a good research thrust to...determine feature relevance and decide if removing any features improves performance. Also, extending the system for simulations using a MIMO receiver or

Feasibility and Effectiveness of Nutritional Telemonitoring for Home Care Clients: A Pilot Study.

PubMed

van Doorn-van Atten, Marije N; Haveman-Nies, Annemien; Heery, Daniel; de Vries, Jeanne H M; de Groot, Lisette C P G M

2018-06-01

Undernutrition has unfavorable consequences for health and quality of life. This pilot study aimed to evaluate the feasibility of a telemonitoring intervention to improve the nutritional status of community-dwelling older adults. The study involved a one-group pretest post-test design, complemented by a qualitative study. The 3-month intervention included 20 Dutch home care clients aged >65 years and consisted of nutritional telemonitoring, television messages, and dietary advice. A process evaluation provided insight into intervention delivery and acceptability. Changes in behavioral determinants, diet quality, appetite, nutritional status, physical functioning, and quality of life were assessed. Researchers and health care professionals implemented the intervention as intended and health care professionals accepted the intervention well. However, 9 participants dropped out, and participants' acceptance was low, mainly due to the low usability of the telemonitoring television channel. Adherence to the telemonitoring measurements was good, although participants needed more help from nurses than anticipated. Participants increased compliance to several Dutch dietary guidelines and no effects on nutritional status, physical functioning, and quality of life were found. Successful telemonitoring of nutritional parameters in community-dwelling older adults starts with optimal usability and acceptability by older adults and their health care professionals. This pilot study provides insight into how to optimize telemonitoring interventions for older adults for maximum impact on behavior and health.

Aversive tension of adolescents with anorexia nervosa in daily course: a case-controlled and smartphone-based ambulatory monitoring trial.

PubMed

Kolar, David Raphael; Bürger, Arne; Hammerle, Florian; Jenetzky, Ekkehart

2014-04-23

Monitoring and reduction of aversive tension is a core issue in dialectical behaviour therapy of patients. It has been shown that aversive tension is increased in adult borderline personality disorder and is linked to low emotion labelling ability. However, until now there is no documented evidence that patients with anorexia nervosa suffer from aversive tension as well. Furthermore the usability of a smartphone application for ambulatory monitoring purposes has not been sufficiently explored. We compare the mean and maximum self-reported aversive tension in 20 female adolescents (12-19 years) with anorexia nervosa in outpatient treatment with 20 healthy controls. They are required to answer hourly, over a 2-day period, that is, about 30 times, four short questions on their smartphone, which ensures prompt documentation without any recall bias. At the close out, the participants give a structured usability feedback on the application and the procedure. The achieved result of this trial has direct relevance for efficient therapy strategies and is a prerequisite for trials regarding dialectical behaviour therapy in anorexia nervosa. The results will be disseminated through peer-review publications. The ethics committee of the regional medical association in Mainz, Germany approved the study protocol under the reference number 837.177.13. The trial is registered at the German clinical trials registration under the reference number DRKS00005228.

First results of mapping sporadic E with a passive observing network

NASA Astrophysics Data System (ADS)

Rice, D. D.; Sojka, J. J.; Eccles, J. V.; Raitt, J. W.; Brady, J. J.; Hunsucker, R. D.

2011-12-01

Sporadic E (Es) can have dramatic effects on communications in the HF and low VHF range, producing over-the-horizon propagation for signals normally restricted to line-of-sight, and sometimes blocking F region propagation of signals in the lower HF range. Measuring the E region winds believed to produce Es is difficult, and no practical means of predicting Es occurrence currently exists other than statistical models. We describe a low-cost observing network based on software-controlled receivers that continuously watches for Es in near-real time using oblique HF propagation from existing transmitters. Results from an 11-day pilot campaign in July 2008 demonstrated that even a limited number of receivers in the network can readily determine the presence and extent of Es patches. These observations indicate that Es often develops quickly over regions of several hundred kilometers rather than gradually drifting across an area. These widespread Es “blooms” have been observed near winter solstice and occasionally at other times of the year; their lifetime depends on the season but can be several hours during the summer. The current network allows the extent of Es in portions of North America to be evaluated: the geographical distribution of Es and bounds on the density of the layer are inferred from its effects on the ionospheric maximum usable frequency (MUF). This study demonstrates quantitatively that Es mapping can provide information about Es layer geographical growth and decay. The observed sudden widespread Es blooms are space weather events that can have significant impact on HF/lower VHF communications and propagation model predictions.

Investigation of radio astronomy image processing techniques for use in the passive millimetre-wave security screening environment

NASA Astrophysics Data System (ADS)

Taylor, Christopher T.; Hutchinson, Simon; Salmon, Neil A.; Wilkinson, Peter N.; Cameron, Colin D.

2014-06-01

Image processing techniques can be used to improve the cost-effectiveness of future interferometric Passive MilliMetre Wave (PMMW) imagers. The implementation of such techniques will allow for a reduction in the number of collecting elements whilst ensuring adequate image fidelity is maintained. Various techniques have been developed by the radio astronomy community to enhance the imaging capability of sparse interferometric arrays. The most prominent are Multi- Frequency Synthesis (MFS) and non-linear deconvolution algorithms, such as the Maximum Entropy Method (MEM) and variations of the CLEAN algorithm. This investigation focuses on the implementation of these methods in the defacto standard for radio astronomy image processing, the Common Astronomy Software Applications (CASA) package, building upon the discussion presented in Taylor et al., SPIE 8362-0F. We describe the image conversion process into a CASA suitable format, followed by a series of simulations that exploit the highlighted deconvolution and MFS algorithms assuming far-field imagery. The primary target application used for this investigation is an outdoor security scanner for soft-sided Heavy Goods Vehicles. A quantitative analysis of the effectiveness of the aforementioned image processing techniques is presented, with thoughts on the potential cost-savings such an approach could yield. Consideration is also given to how the implementation of these techniques in CASA might be adapted to operate in a near-field target environment. This may enable a much wider usability by the imaging community outside of radio astronomy and thus would be directly relevant to portal screening security systems in the microwave and millimetre wave bands.

Evaluating Usability in a Distance Digital Systems Laboratory Class

ERIC Educational Resources Information Center

Kostaras, N.; Xenos, M.; Skodras, A. N.

2011-01-01

This paper presents the usability evaluation of a digital systems laboratory class offered to distance-learning students. It details the way in which students can participate remotely in such a laboratory, the methodology employed in the usability assessment of the laboratory infrastructure (hardware and software), and also outlines the main…

A Usability Evaluation of Academic Virtual Reference Services

ERIC Educational Resources Information Center

Chow, Anthony S.; Croxton, Rebecca A.

2014-01-01

This study examined the usability of five virtual reference services--instant messenger chat, e-mail, telephone, text messaging, and Skype videoconferencing--by having 31 undergraduate and graduate students evaluate the usability of the virtual reference services of two different universities. The study's results suggest that user preference and…

An Online Social Constructivist Course: Toward a Framework for Usability Evaluations

ERIC Educational Resources Information Center

Phillips, Alana S.; Sheffield, Anneliese; Moore, Michelle; Robinson, Heather A.

2016-01-01

There is a need for a holistic usability evaluation framework that accommodates social constructivist online courses. Social knowledge construction may not be adequately evaluated using current frameworks. This qualitative research study examined the usability needs of a social constructivist online course. Data from an online course were analyzed…

A Call for Bioimaging Software Usability

PubMed Central

Carpenter, Anne E.; Kamentsky, Lee; Eliceiri, Kevin W.

2013-01-01

Bioimaging software developed in a research setting often fails to be widely used by the scientific community. We suggest that, to maximize both the public’s and researchers’ investments, usability should be a more highly valued goal. We describe specific characteristics of usability towards which bioimaging software projects should aim. PMID:22743771

Training Teachers and Serving Students: Applying Usability Testing in Writing Programs

ERIC Educational Resources Information Center

McGovern, Heather

2007-01-01

Teachers often test course materials by using them in class. Usability testing provides an alternative: teachers receive student feedback and revise materials "before" teaching a class. Case studies based on interviews and observations with two teaching assistants who usability tested materials before teaching introductory technical writing…

Usability Assessment of E-Café Operational Management Simulation Game

ERIC Educational Resources Information Center

Chang, Chiung-sui; Huang, Ya-Ping

2013-01-01

To ensure the quality of digital simulation game, we utilized the usability evaluation heuristic in the design and development processes of e-café operational management game-based learning material for students. The application of usability evaluations during this study is described. Additionally, participant selection, data collection and…

Users Views about the Usability of Digital Libraries

ERIC Educational Resources Information Center

Koohang, Alex; Ondracek, James

2005-01-01

This study examined users' views about the usability of digital libraries' current and perceived importance. Age, gender, prior experience with the Internet, college status, and digital library proficiency are the independent variables. Users' current views about the usability of digital libraries and users perceived importance of digital library…

A systematic review of usability test metrics for mobile video streaming apps

NASA Astrophysics Data System (ADS)

Hussain, Azham; Mkpojiogu, Emmanuel O. C.

2016-08-01

This paper presents the results of a systematic review regarding the usability test metrics for mobile video streaming apps. In the study, 238 studies were found, but only 51 relevant papers were eventually selected for the review. The study reveals that time taken for video streaming and the video quality were the two most popular metrics used in the usability tests for mobile video streaming apps. Besides, most of the studies concentrated on the usability of mobile TV as users are switching from traditional TV to mobile TV.

Task-specific usability requirements of electronic medical records systems: Lessons learned from a national survey of end-users.

PubMed

Farzandipour, Mehrdad; Meidani, Zahra; Riazi, Hossein; Sadeqi Jabali, Monireh

2018-09-01

There are various approaches to evaluating the usability of electronic medical record (EMR) systems. User perspectives are an integral part of evaluation. Usability evaluations efficiently and effectively contribute to user-centered design and supports tasks and increase user satisfaction. This study determined the main usability requirements for EMRs by means of an end-user survey. A mixed-method strategy was conducted in three phases. A qualitative approach was employed to collect and formulate EMR usability requirements using the focus group method and the modified Delphi technique. Classic Delphi technique was used to evaluate the proposed requirements among 380 end-users in Iran. The final list of EMR usability requirements was verified and included 163 requirements divided into nine groups. The highest rates of end-user agreement relate to EMR visual clarity (3.65 ± 0.61), fault tolerance (3.58 ± 0.56), and suitability for learning (3.55 ± 0.54). The lowest end-user agreement was for auditory presentation (3.18 ± 0.69). The highest and lowest agreement among end-users was for visual clarity and auditory presentation by EMRs, respectively. This suggests that user priorities in determination of EMR usability and their understanding of the importance of the types of individual tasks and context characteristics differ.

A literature review about usability evaluation methods for e-learning platforms.

PubMed

Freire, Luciana Lopes; Arezes, Pedro Miguel; Campos, José Creissac

2012-01-01

The usability analysis of information systems has been the target of several research studies over the past thirty years. These studies have highlighted a great diversity of points of view, including researchers from different scientific areas such as Ergonomics, Computer Science, Design and Education. Within the domain of information ergonomics, the study of tools and methods used for usability evaluation dedicated to E-learning presents evidence that there is a continuous and dynamic evolution of E-learning systems, in many different contexts -academics and corporative. These systems, also known as LMS (Learning Management Systems), can be classified according to their educational goals and their technological features. However, in these systems the usability issues are related with the relationship/interactions between user and system in the user's context. This review is a synthesis of research project about Information Ergonomics and embraces three dimensions, namely the methods, models and frameworks that have been applied to evaluate LMS. The study also includes the main usability criteria and heuristics used. The obtained results show a notorious change in the paradigms of usability, with which it will be possible to discuss about the studies carried out by different researchers that were focused on usability ergonomic principles aimed at E-learning.

Usability of online psychoeducation for siblings of people with psychosis.

PubMed

Sin, Jacqueline; Henderson, Claire; Norman, Ian

2014-10-01

The E Sibling Project aims to address the needs of siblings of individuals affected by psychosis through provision of a comprehensive online intervention. The online intervention comprises four core elements, including: information on psychosis; various coping and promoting well-being strategies; siblings' blogs and discussion forum with peers; and an "Ask the Experts" function. After the intervention-prototype was developed, we tested its feasibility, usability and acceptability by siblings. We evaluated the usability of the intervention-prototype using a non-randomised usability study with siblings of individuals diagnosed with psychosis. The usability study adapted Poulson et al's framework to collect subjective feedback from participants on ease of use, perceived usefulness and acceptability, together with objective usage data on the intervention. Twenty siblings were recruited to the usability test; 19 tried out the resource-prototype over a 4-week period and 17 completed the online evaluation after using the intervention. In total, 906 page-views were made by the participants and each spent about two hours using the resource. Participants evaluated the intervention as helpful, relevant and useful in terms of content, design and usability. Developments are needed to improve the navigation and intuitiveness of the resource. Using an internet-based information-giving and peer support intervention to promote wellbeing and coping is feasible and acceptable to siblings of people with psychosis.

The STEP database through the end-users eyes--USABILITY STUDY.

PubMed

Salunke, Smita; Tuleu, Catherine

2015-08-15

The user-designed database of Safety and Toxicity of Excipients for Paediatrics ("STEP") is created to address the shared need of drug development community to access the relevant information of excipients effortlessly. Usability testing was performed to validate if the database satisfies the need of the end-users. Evaluation framework was developed to assess the usability. The participants performed scenario based tasks and provided feedback and post-session usability ratings. Failure Mode Effect Analysis (FMEA) was performed to prioritize the problems and improvements to the STEP database design and functionalities. The study revealed several design vulnerabilities. Tasks such as limiting the results, running complex queries, location of data and registering to access the database were challenging. The three critical attributes identified to have impact on the usability of the STEP database included (1) content and presentation (2) the navigation and search features (3) potential end-users. Evaluation framework proved to be an effective method for evaluating database effectiveness and user satisfaction. This study provides strong initial support for the usability of the STEP database. Recommendations would be incorporated into the refinement of the database to improve its usability and increase user participation towards the advancement of the database. Copyright © 2015 Elsevier B.V. All rights reserved.

How Do Clinical Information Systems Affect the Cognitive Demands of General Practitioners?: Usability Study with a Focus on Cognitive Workload.

PubMed

Ariza, Ferran; Kalra, Dipak; Potts, Henry Ww

2015-11-20

Clinical information systems in the National Health Service do not need to conform to any explicit usability requirements. Poor usability can increase the mental workload experienced by clinicians and cause fatigue, increase error rates and impact the overall patient safety. Mental workload can be used as a measure of usability. To assess the subjective cognitive workload experienced by general practitioners (GPs) with their systems. To raise awareness of the importance of usability in system design among users, designers, developers and policymakers. We used a modified version of the NASA Task Load Index, adapted for web. We developed a set of common clinical scenarios and computer tasks on an online survey. We emailed the study link to 199 clinical commissioning groups and 1,646 GP practices in England. Sixty-seven responders completed the survey. The respondents had spent an average of 17 years in general practice, had experience of using a mean of 1.5 GP computer systems and had used their current system for a mean time of 6.7 years. The mental workload score was not different among systems. There were significant differences among the task scores, but these differences were not specific to particular systems. The overall score and task scores were related to the length of experience with their present system. Four tasks imposed a higher mental workload on GPs: 'repeat prescribing', 'find episode', 'drug management' and 'overview records'. Further usability studies on GP systems should focus on these tasks. Users, policymakers, designers and developers should remain aware of the importance of usability in system design.What does this study add?• Current GP systems in England do not need to conform to explicit usability requirements. Poor usability can increase the mental workload of clinicians and lead to errors.• Some clinical computer tasks incur more cognitive workload than others and should be considered carefully during the design of a system.• GPs did not report overall very high levels of subjective cognitive workload when undertaking common clinical tasks with their systems.• Further usability studies on GP systems should focus on the tasks incurring higher cognitive workload.• Users, policymakers, and designers and developers should remain aware of the importance of usability in system design.

Efficient waveform tomography for lithospheric imaging: implications for realistic, two-dimensional acquisition geometries and low-frequency data

NASA Astrophysics Data System (ADS)

Brenders, A. J.; Pratt, R. G.

2007-01-01

We provide a series of numerical experiments designed to test waveform tomography under (i) a reduction in the number of input data frequency components (`efficient' waveform tomography), (ii) sparse spatial subsampling of the input data and (iii) an increase in the minimum data frequency used. These results extend the waveform tomography results of a companion paper, using the same third-party, 2-D, wide-angle, synthetic viscoelastic seismic data, computed in a crustal geology model 250 km long and 40 km deep, with heterogeneous P-velocity, S-velocity, density and Q-factor structure. Accurate velocity models were obtained using efficient waveform tomography and only four carefully selected frequency components of the input data: 0.8, 1.7, 3.6 and 7.0 Hz. This strategy avoids the spectral redundancy present in `full' waveform tomography, and yields results that are comparable with those in the companion paper for an 88 per cent decrease in total computational cost. Because we use acoustic waveform tomography, the results further justify the use of the acoustic wave equation in calculating P-wave velocity models from viscoelastic data. The effect of using sparse survey geometries with efficient waveform tomography were investigated for both increased receiver spacing, and increased source spacing. Sampling theory formally requires spatial sampling at maximum interval of one half-wavelength (2.5 km at 0.8 Hz): For data with receivers every 0.9 km (conforming to this criterion), artefacts in the tomographic images were still minimal when the source spacing was as large as 7.6 km (three times the theoretical maximum). Larger source spacings led to an unacceptable degradation of the results. When increasing the starting frequency, image quality was progressively degraded. Acceptable image quality within the central portion of the model was nevertheless achieved using starting frequencies up to 3.0 Hz. At 3.0 Hz the maximum theoretical sample interval is reduced to 0.67 km due to the decreased wavelengths; the available sources were spaced every 5.0 km (more than seven times the theoretical maximum), and receivers were spaced every 0.9 km (1.3 times the theoretical maximum). Higher starting frequencies than 3.0 Hz again led to unacceptable degradation of the results.

Cluster analysis based on dimensional information with applications to feature selection and classification

NASA Technical Reports Server (NTRS)

Eigen, D. J.; Fromm, F. R.; Northouse, R. A.

1974-01-01

A new clustering algorithm is presented that is based on dimensional information. The algorithm includes an inherent feature selection criterion, which is discussed. Further, a heuristic method for choosing the proper number of intervals for a frequency distribution histogram, a feature necessary for the algorithm, is presented. The algorithm, although usable as a stand-alone clustering technique, is then utilized as a global approximator. Local clustering techniques and configuration of a global-local scheme are discussed, and finally the complete global-local and feature selector configuration is shown in application to a real-time adaptive classification scheme for the analysis of remote sensed multispectral scanner data.

User Interface Problems of a Nationwide Inpatient Information System: A Heuristic Evaluation.

PubMed

Atashi, Alireza; Khajouei, Reza; Azizi, Amirabbas; Dadashi, Ali

2016-01-01

While studies have shown that usability evaluation could uncover many design problems of health information systems, the usability of health information systems in developing countries using their native language is poorly studied. The objective of this study was to evaluate the usability of a nationwide inpatient information system used in many academic hospitals in Iran. Three trained usability evaluators independently evaluated the system using Nielsen's 10 usability heuristics. The evaluators combined identified problems in a single list and independently rated the severity of the problems. We statistically compared the number and severity of problems identified by HIS experienced and non-experienced evaluators. A total of 158 usability problems were identified. After removing duplications 99 unique problems were left. The highest mismatch with usability principles was related to "Consistency and standards" heuristic (25%) and the lowest related to "Flexibility and efficiency of use" (4%). The average severity of problems ranged from 2.4 (Major problem) to 3.3 (Catastrophe problem). The experienced evaluator with HIS identified significantly more problems and gave higher severities to problems (p<0.02). Heuristic Evaluation identified a high number of usability problems in a widely used inpatient information system in many academic hospitals. These problems, if remain unsolved, may waste users' and patients' time, increase errors and finally threaten patient's safety. Many of them can be fixed with simple redesign solutions such as using clear labels and better layouts. This study suggests conducting further studies to confirm the findings concerning effect of evaluator experience on the results of Heuristic Evaluation.

User Interface Problems of a Nationwide Inpatient Information System: A Heuristic Evaluation

PubMed Central

Atashi, Alireza; Azizi, Amirabbas; Dadashi, Ali

2016-01-01

Summary Introduction While studies have shown that usability evaluation could uncover many design problems of health information systems, the usability of health information systems in developing countries using their native language is poorly studied. The objective of this study was to evaluate the usability of a nationwide inpatient information system used in many academic hospitals in Iran. Material and Methods Three trained usability evaluators independently evaluated the system using Nielsen’s 10 usability heuristics. The evaluators combined identified problems in a single list and independently rated the severity of the problems. We statistically compared the number and severity of problems identified by HIS experienced and non-experienced evaluators. Results A total of 158 usability problems were identified. After removing duplications 99 unique problems were left. The highest mismatch with usability principles was related to “Consistency and standards” heuristic (25%) and the lowest related to “Flexibility and efficiency of use” (4%). The average severity of problems ranged from 2.4 (Major problem) to 3.3 (Catastrophe problem). The experienced evaluator with HIS identified significantly more problems and gave higher severities to problems (p<0.02). Discussion Heuristic Evaluation identified a high number of usability problems in a widely used inpatient information system in many academic hospitals. These problems, if remain unsolved, may waste users’ and patients’ time, increase errors and finally threaten patient’s safety. Many of them can be fixed with simple redesign solutions such as using clear labels and better layouts. This study suggests conducting further studies to confirm the findings concerning effect of evaluator experience on the results of Heuristic Evaluation. PMID:27081409

Evaluating Usability of Radiology Information Systems in Hospitals of Tabriz University of Medical Sciences.

PubMed

Rezaei-Hachesu, Peyman; Pesianian, Esmaeil; Mohammadian, Mohsen

2016-02-01

Radiology information system (RIS) in order to reduce workload and improve the quality of services must be well-designed. Heuristic evaluation is one of the methods that understand usability problems with the least time, cost and resources. The aim of present study is to evaluate the usability of RISs in hospitals. This is a cross-sectional descriptive study (2015) that uses heuristic evaluation method to evaluate the usability of RIS used in 3 hospitals of Tabriz city. The data are collected using a standard checklist based on 13 principles of Nielsen Heuristic evaluation method. Usability of RISs was investigated based on the number of components observed from Nielsen principles and problems of usability based on the number of non-observed components as well as non-existent or unrecognizable components. by evaluation of RISs in each of the hospitals 1, 2 and 3, total numbers of observed components were obtained as 173, 202 and 196, respectively. It was concluded that the usability of RISs in the studied population, on average and with observing 190 components of the 291 components related to the 13 principles of Nielsen is 65.41 %. Furthermore, problems of usability were obtained as 26.35%. The established and visible nature of some components such as response time of application, visual feedbacks, colors, view and design and arrangement of software objects cause more attention to these components as principal components in designing UI software. Also, incorrect analysis before system design leads to a lack of attention to secondary needs like Help software and security issues.

Applying heuristic evaluation to improve the usability of a telemedicine system.

PubMed

Tang, Zhihua; Johnson, Todd R; Tindall, R Douglas; Zhang, Jiajie

2006-02-01

The development of a telemedicine system should not only take advantage of technological advances but also pay close attention to users and the human issues involved. In this paper we examine the utility of heuristic evaluation in improving the usability of a digital emergency medical services (EMS) system equipped on an ambulance. The digital EMS system used advanced communication technologies to help remotely located trauma specialists gain access to patient data in real-time and direct life-saving measures in a timely fashion. To improve its usability, three experts inspected prototypes of the system according to 14 software usability heuristics. The analyses revealed information on the prevalence, severity, and nature of heuristic violations in the user interface design. The results were subsequently utilized to guide the iterative software design process. A comparison between two consecutive prototypes showed that the second design had only half as many usability violations as the first prototype and had considerable improvement in a number of usability heuristic categories. The validity of heuristic evaluation was examined in an ethnographic study of paramedics using a prototype of the system in their work environment. Users' task performances partially verified heuristic evaluation results. However, they also revealed problems that were not identified in heuristic evaluation but only became prominent during field observation. In conclusion, we argue that usability should be given high priority in the development of a telemedicine system, and that heuristic evaluation can be an effective and efficient way to identify usability problems in the early stage of software development.

The acoustical cues to sound location in the Guinea pig (cavia porcellus)

PubMed Central

Greene, Nathanial T; Anbuhl, Kelsey L; Williams, Whitney; Tollin, Daniel J.

2014-01-01

There are three main acoustical cues to sound location, each attributable to space-and frequency-dependent filtering of the propagating sound waves by the outer ears, head, and torso: Interaural differences in time (ITD) and level (ILD) as well as monaural spectral shape cues. While the guinea pig has been a common model for studying the anatomy, physiology, and behavior of binaural and spatial hearing, extensive measurements of their available acoustical cues are lacking. Here, these cues were determined from directional transfer functions (DTFs), the directional components of the head-related transfer functions, for eleven adult guinea pigs. In the frontal hemisphere, monaural spectral notches were present for frequencies from ~10 to 20 kHz; in general, the notch frequency increased with increasing sound source elevation and in azimuth toward the contralateral ear. The maximum ITDs calculated from low-pass filtered (2 kHz cutoff frequency) DTFs were ~250 µs, whereas the maximum ITD measured with low frequency tone pips was over 320 µs. A spherical head model underestimates ITD magnitude under normal conditions, but closely approximates values when the pinnae were removed. Interaural level differences (ILDs) strongly depended on location and frequency; maximum ILDs were < 10 dB for frequencies < 4 kHz and were as large as 40 dB for frequencies > 10 kHz. Removal of the pinna reduced the depth and sharpness of spectral notches, altered the acoustical axis, and reduced the acoustical gain, ITDs, and ILDs; however, spectral shape features and acoustical gain were not completely eliminated, suggesting a substantial contribution of the head and torso in altering the sounds present at the tympanic membrane. PMID:25051197

Performance Investigation of Millimeter Wave Generation Reliant on Stimulated Brillouin Scattering

NASA Astrophysics Data System (ADS)

Tickoo, Sheetal; Gupta, Amit

2018-04-01

In this work, photonic method of generating the millimeter waves has been done based on Brillouin scattering effect in optical fiber. Here different approaches are proposed to get maximum frequency shift in mm-wave region using only pumps, radio signals with Mach-Zehnder modulator. Moreover for generated signal validation, signals modulated and send to both wired and wireless medium in optical domain. It is observed that maximum shift of 300 GHz is realized using 60 GHz input sine wave. Basically a frequency doubler is proposed which double shift of input frequency and provide better SNR. For the future generation network system, the generation of millimeter waves makes them well reliable for the transmission of the data.

A frequency doubled pressure-tunable oscillator-amplifier dye laser system

NASA Technical Reports Server (NTRS)

Moriarty, A.; Heaps, W.; Davis, D. D.

1976-01-01

A tunable high-repetition-rate oscillator-amplifier dye-laser system is reported. The dye laser described was longitudinally pumped with the second harmonic of a Nd-YAG laser operating at 10 Hz. Using three Faraday-Perot etalons and pressure tuning, a maximum fundamental output power of the order of 6 MW with a corresponding spectral width of less than 0.003 nm at 564 nm was obtained. The fundamental at 564 nm was frequency doubled to give a maximum power level of 0.6 MW of second-harmonic output power with a spectral width less than 0.0015 nm at 282 nm. Frequency stability could be maintained to within approximately 15% of the line-width.

Variability of the occurrence frequency of solar flares as a function of peak hard X-ray rate

NASA Technical Reports Server (NTRS)

Bai, T.

1993-01-01

We study the occurrence frequency of solar flares as a function of the hard X-ray peak count rate, using observations of the Solar Maximum Mission. The size distributions are well represented by power-law distributions with negative indices. As a better alternative to the conventional method, we devise a maximum likelihood method of determining the power-law index of the size distribution. We find that the power-law index of the size distribution changes with time and with the phase of the 154-day periodicity. The size distribution is steeper during the maximum years of solar cycle 21 (1980 and 1981) than during the declining phase (1982-1984). The size distribution, however, is flatter during the maximum phase of the 154-day periodicity than during the minimum phase. The implications of these findings are discussed.

New Options for Usability Testing Projects in Business Communication Courses

ERIC Educational Resources Information Center

Jameson, Daphne A.

2013-01-01

The increasing availability of recording technologies makes it easier to include usability testing projects in business communication courses. Usability testing is a method of discovering whether people can navigate, read, and understand a print or electronic communication well enough to achieve a particular purpose in a reasonable time frame.…

Collecting and Applying Usability Data from Distance Learners

ERIC Educational Resources Information Center

Mitchell, Emily; West, Brandon

2017-01-01

Growth of their college's off-campus and online course offerings led librarians at SUNY Oswego to run usability tests with off-campus students to compensate for a lack of responses from this population during earlier usability testing. Constraints on testing with off-campus students included lack of funding and librarian time, as well as…

Evaluation of Usability Utilizing Markov Models

ERIC Educational Resources Information Center

Penedo, Janaina Rodrigues; Diniz, Morganna; Ferreira, Simone Bacellar Leal; Silveira, Denis S.; Capra, Eliane

2012-01-01

Purpose: The purpose of this paper is to analyze the usability of a remote learning system in its initial development phase, using a quantitative usability evaluation method through Markov models. Design/methodology/approach: The paper opted for an exploratory study. The data of interest of the research correspond to the possible accesses of users…

Adding Users to the Website Design Process

ERIC Educational Resources Information Center

Tomeo, Megan L.

2012-01-01

Alden Library began redesigning its website over a year ago. Throughout the redesign process the students, faculty, and staff that make up the user base were added to the conversation by utilizing several usability test methods. This article focuses on the usability testing conducted at Alden Library and delves into future usability testing, which…

Effect of Improving the Usability of an E-Learning Resource: A Randomized Trial

ERIC Educational Resources Information Center

Davids, Mogamat Razeen; Chikte, Usuf M. E.; Halperin, Mitchell L.

2014-01-01

Optimizing the usability of e-learning materials is necessary to reduce extraneous cognitive load and maximize their potential educational impact. However, this is often neglected, especially when time and other resources are limited. We conducted a randomized trial to investigate whether a usability evaluation of our multimedia e-learning…

The Virtual Anatomy Laboratory: Usability Testing to Improve an Online Learning Resource for Anatomy Education

ERIC Educational Resources Information Center

Doubleday, Eldridge G.; O'Loughlin, Valerie D.; Doubleday, Alison F.

2011-01-01

An increasing number of instructors are seeking to provide students with online anatomy resources. Many researchers have attempted to identify associations between resource use and student learning but few studies discuss the importance of usability testing in resource design and modification. Usability testing provides information about ease of…

Training Software Developers and Designers to Conduct Usability Evaluations

ERIC Educational Resources Information Center

Skov, Mikael Brasholt; Stage, Jan

2012-01-01

Many efforts to improve the interplay between usability evaluation and software development rely either on better methods for conducting usability evaluations or on better formats for presenting evaluation results in ways that are useful for software designers and developers. Both of these approaches depend on a complete division of work between…

The Relationship between National Culture and the Usability of an E-Learning System

ERIC Educational Resources Information Center

Downey, Steve; Wentling, Rose Mary; Wentling, Tim; Wadsworth, Andrew

2004-01-01

This study sought to measure the relationship between national culture and the usability of an e-Learning system by using Hofstede's cultural dimensions and Nielson's usability attributes. The study revealed that high uncertainty avoidance cultures found the system more frustrating to use. The study also revealed that individuals from cultures…

Grappling with Distributed Usability: A Cultural-Historical Examination of Documentation Genres Over Four Decades.

ERIC Educational Resources Information Center

Spinuzzi, Clay

2001-01-01

Describes and illustrates a distributed approach to usability (envisioning usability across the genres, practices, uses, and goals of a given activity) using a four-decade examination of a traffic accident location and analysis system. Uses the theoretical framework of "genre ecologies" to show how communities of users interact with…

Design and Usability of Digital Libraries: Case Studies in the Asia Pacific

ERIC Educational Resources Information Center

Theng, Yin-Leng, Ed.; Foo, Schubert, Ed.

2005-01-01

This book showcases some of the best digital library practices from organizations in the Asia Pacific. Particular emphasis has been placed on the design, use and usability of digital libraries. Not only are digital libraries examined, but related technologies, the management of knowledge in digital libraries, and the associated usability and…

Usability Studies and User-Centered Design in Digital Libraries

ERIC Educational Resources Information Center

Comeaux, David J.

2008-01-01

Digital libraries continue to flourish. At the same time, the principles of user-centered design and the practice of usability testing have been growing in popularity, spreading their influence into the library sphere. This article explores the confluence of these two trends by surveying the current literature on usability studies of digital…

Earning the Stamp of Approval: How To Achieve Optimal Usability.

ERIC Educational Resources Information Center

Makar, Susan

2003-01-01

Describes the redesign of the Web site at the virtual library of the NIST (National Institute of Standards and Technology). Discusses usability problems with the original site, including navigation difficulties; focus groups to determine user needs; usability testing for the new Web site; and the importance of customer input. (LRW)

Using Eye Trackers for Usability Evaluation of Health Information Technology: A Systematic Literature Review

PubMed Central

Yang, Yushi

2015-01-01

Background Eye-tracking technology has been used to measure human cognitive processes and has the potential to improve the usability of health information technology (HIT). However, it is still unclear how the eye-tracking method can be integrated with other traditional usability methodologies to achieve its full potential. Objective The objective of this study was to report on HIT evaluation studies that have used eye-tracker technology, and to envision the potential use of eye-tracking technology in future research. Methods We used four reference databases to initially identify 5248 related papers, which resulted in only 9 articles that met our inclusion criteria. Results Eye-tracking technology was useful in finding usability problems in many ways, but is still in its infancy for HIT usability evaluation. Limited types of HITs have been evaluated by eye trackers, and there has been a lack of evaluation research in natural settings. Conclusions More research should be done in natural settings to discover the real contextual-based usability problems of clinical and mobile HITs using eye-tracking technology with more standardized methodologies and guidance. PMID:27026079

Internationalization and localization: evaluating and testing a Website for Asian users.

PubMed

Rau, Pei-Luen Patrick; Liang, Sheau-Farn Max

2003-01-15

The objective of this study was to combine internationalization and localization of Websites and improvement of Website usability with user-centred design methods. This study designed for internationalization and localization of Websites for Asian users, and implemented usability engineering into every phase of Website usability testing, based on the internationalization and localization perspectives of the honeywell.com/your home Website. The first step was to develop the usage scenarios. Three Asian usability specialists carried out one heuristic evaluation session for the current honeywell.com/your home Website. The usability problems were analysed and possible solutions to these problems were discussed. In the next phase, cluster analysis was utilized to test current information architecture. The results provided options for future information architecture development for this Website. Finally, a performance measurement test was conducted to investigate the performance for Asian users. Based on the results, suggestions for improving the Website usability from the localization perspective were provided. The results demonstrate the user-centred design (UCD) approach and stress international and local issues in Website development to Website designers.

The Cultural Evolution of Human Communication Systems in Different Sized Populations: Usability Trumps Learnability

PubMed Central

Fay, Nicolas; Ellison, T. Mark

2013-01-01

This study examines the intergenerational transfer of human communication systems. It tests if human communication systems evolve to be easy to learn or easy to use (or both), and how population size affects learnability and usability. Using an experimental-semiotic task, we find that human communication systems evolve to be easier to use (production efficiency and reproduction fidelity), but harder to learn (identification accuracy) for a second generation of naïve participants. Thus, usability trumps learnability. In addition, the communication systems that evolve in larger populations exhibit distinct advantages over those that evolve in smaller populations: the learnability loss (from the Initial signs) is more muted and the usability benefits are more pronounced. The usability benefits for human communication systems that evolve in a small and large population is explained through guided variation reducing sign complexity. The enhanced performance of the communication systems that evolve in larger populations is explained by the operation of a content bias acting on the larger pool of competing signs. The content bias selects for information-efficient iconic signs that aid learnability and enhance usability. PMID:23967243

Connection between competence, usability, environment and risk of falls in elderly adults.

PubMed

Leiva-Caro, José Alex; Salazar-González, Bertha Cecilia; Gallegos-Cabriales, Esther Carlota; Gómez-Meza, Marco Vinicio; Hunter, Kathleen F

2015-01-01

To determine connections between competence, usability, environment and risk of falls in elderly adults. Correlational descriptive study, 123 elderly adults, both male and female, aged 70 years and older were included. Data was collected via the Tinetti Scale, CESD-7 Scale, Montreal Cognitive Assessment, Usability Questionnaire on Housing and Housing Enabler; and sociodemographic and health background certificate data. For data analysis, descriptive and inferential statistics were used, multivariate linear and logistic regression models were adjusted. 42.0% of the elderly adults had presented with falls, with a higher prevalence in women, and in the group of 70-75 years. The physical environment of the house, gait, and usability were set as risk factors for falls. A negative relationship between usability and depressive symptoms, cognitive health, balance, gait, the social and physical environment was found, p <0.05; and a strong positive correlation between walking and balance, p <0.05. This study helps to better understand the phenomenon of falling, to find a connection between usability with the risk of falls, and other variables.

Connection between competence, usability, environment and risk of falls in elderly adults

PubMed Central

Leiva-Caro, José Alex; Salazar-González, Bertha Cecilia; Gallegos-Cabriales, Esther Carlota; Gómez-Meza, Marco Vinicio; Hunter, Kathleen F.

2015-01-01

Objective: to determine connections between competence, usability, environment and risk of falls in elderly adults. Method: correlational descriptive study, 123 elderly adults, both male and female, aged 70 years and older were included. Data was collected via the Tinetti Scale, CESD-7 Scale, Montreal Cognitive Assessment, Usability Questionnaire on Housing and Housing Enabler; and sociodemographic and health background certificate data. For data analysis, descriptive and inferential statistics were used, multivariate linear and logistic regression models were adjusted. Results: 42.0% of the elderly adults had presented with falls, with a higher prevalence in women, and in the group of 70-75 years. The physical environment of the house, gait, and usability were set as risk factors for falls. A negative relationship between usability and depressive symptoms, cognitive health, balance, gait, the social and physical environment was found, p <0.05; and a strong positive correlation between walking and balance, p <0.05. Conclusion: this study helps to better understand the phenomenon of falling, to find a connection between usability with the risk of falls, and other variables. PMID:26626006

The cultural evolution of human communication systems in different sized populations: usability trumps learnability.

PubMed

Fay, Nicolas; Ellison, T Mark

2013-01-01

This study examines the intergenerational transfer of human communication systems. It tests if human communication systems evolve to be easy to learn or easy to use (or both), and how population size affects learnability and usability. Using an experimental-semiotic task, we find that human communication systems evolve to be easier to use (production efficiency and reproduction fidelity), but harder to learn (identification accuracy) for a second generation of naïve participants. Thus, usability trumps learnability. In addition, the communication systems that evolve in larger populations exhibit distinct advantages over those that evolve in smaller populations: the learnability loss (from the Initial signs) is more muted and the usability benefits are more pronounced. The usability benefits for human communication systems that evolve in a small and large population is explained through guided variation reducing sign complexity. The enhanced performance of the communication systems that evolve in larger populations is explained by the operation of a content bias acting on the larger pool of competing signs. The content bias selects for information-efficient iconic signs that aid learnability and enhance usability.

The Imperative of Solving Nurses' Usability Problems With Health Information Technology.

PubMed

Staggers, Nancy; Elias, Beth L; Makar, Ellen; Alexander, Gregory L

2018-04-01

Health information technology (IT) usability issues are a key concern for nurse executives and nurses. The aims of this study are to understand usability pain points faced by nurses regarding the use of health IT, identify their impact and importance, discuss responsibilities, and develop possible solutions to improve the health IT-user experience for nurses. Twenty-seven experts were interviewed including nursing leaders, informaticists, executives, engineers, researchers, and human factors experts across acute care, long-term care, and vendor settings. Semistructured questions guided the interviews, and content analysis was used to identify themes. Four themes emerged: 1) user experience pain points, 2) importance of the issues, 3) the responsibility gap, and 4) acting on usability issues. Nurses continue to endure significant health IT-usability issues that negatively impact patients, nurses, and healthcare organizations. Solutions include enhancing the voice of nursing at the national and local levels, creating a digital strategy for nursing, providing incentives to improve usability in health IT, and accelerating the understanding of nurses' work intended to inform and translate nurses' work into health IT design.

The influence of socio-cultural background and product value in usability testing.

PubMed

Sonderegger, Andreas; Sauer, Juergen

2013-05-01

This article examines the influence of socio-cultural background and product value on different outcomes of usability tests. A study was conducted in two different socio-cultural regions, Switzerland and East Germany, which differed in a number of aspects (e.g. economic power, price sensitivity and culture). Product value (high vs. low) was varied by manipulating the price of the product. Sixty-four test participants were asked to carry out five typical user tasks in the context of coffee machine usage, measuring performance, perceived usability, and emotion. The results showed that in Switzerland, high-value products were rated higher in usability than low-value products whereas in East Germany, high-value products were evaluated lower in usability. A similar interaction effect of socio-cultural background and product value was observed for user emotion. Implications are that the outcomes of usability tests do not allow for a simple transfer across cultures and that the mediating influence of perceived product value needs to be taken into consideration. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Prediction of scour depth in gravel bed rivers using radio frequency IDs : application to the Skagit River.

DOT National Transportation Integrated Search

2013-10-01

The overarching goal of the proposed research was to develop, test and verify a robust system based on the Low Frequency (134.2 : kHz), passive Radio Frequency Identification (RFID) technology to be ultimately used for determining the maximum scour d...

The CO2 laser frequency stability measurements

NASA Technical Reports Server (NTRS)

Johnson, E. H., Jr.

1973-01-01

Carbon dioxide laser frequency stability data are considered for a receiver design that relates to maximum Doppler frequency and its rate of change. Results show that an adequate margin exists in terms of data acquisition, Doppler tracking, and bit error rate as they relate to laser stability and transmitter power.

Evaluating input device usability as a function of task difficulty in a tracking task.

PubMed

Rupp, Michael A; Oppold, Paul; McConnell, Daniel S

2015-01-01

Game controllers are emerging as a preferred choice for the manual control of unmanned vehicles, but an understanding of their usability characteristics has yet to emerge. We compared the usability of an Xbox 360 game controller in a dual task situation using MATB II to the traditional joystick and keyboard interface in two experiments. In the first experiment, performance with the game controller was associated with fewer tracking errors. In a second experiment, we trained users on the devices, and found that even after training the game controller was still associated with fewer tracking errors as well as higher usability and lower workload ratings. These results are consistent with the idea that game controllers are highly usable input devices and do not require high mental workload to operate, thus making them suitable for complex control tasks.

Varactor diode assembly with low parasitic reactances

NASA Technical Reports Server (NTRS)

Dickens, L. E.

1975-01-01

Development of varactor diode assembly overcomes parasitic reactances of conventional varactor packages. In specially constructed assembly very high idler-frequency to signal-frequency ratios are used to obtain low-noise operation over maximum bandwidth.

Enhancement-mode GaAs metal-oxide-semiconductor high-electron-mobility transistors with atomic layer deposited Al2O3 as gate dielectric

NASA Astrophysics Data System (ADS)

Lin, H. C.; Yang, T.; Sharifi, H.; Kim, S. K.; Xuan, Y.; Shen, T.; Mohammadi, S.; Ye, P. D.

2007-11-01

Enhancement-mode GaAs metal-oxide-semiconductor high-electron-mobility transistors (MOS-HEMTs) with ex situ atomic-layer-deposited Al2O3 as gate dielectrics are studied. Maximum drain currents of 211 and 263mA/mm are obtained for 1μm gate-length Al2O3 MOS-HEMTs with 3 and 6nm thick gate oxide, respectively. C-V characteristic shows negligible hysteresis and frequency dispersion. The gate leakage current density of the MOS-HEMTs is 3-5 orders of magnitude lower than the conventional HEMTs under similar bias conditions. The drain current on-off ratio of MOS-HEMTs is ˜3×103 with a subthreshold swing of 90mV/decade. A maximum cutoff frequency (fT) of 27.3GHz and maximum oscillation frequency (fmax) of 39.9GHz and an effective channel mobility of 4250cm2/Vs are measured for the 1μm gate-length Al2O3 MOS-HEMT with 6nm gate oxide. Hooge's constant measured by low frequency noise spectral density characterization is 3.7×10-5 for the same device.

A low-frequency MEMS piezoelectric energy harvester with a rectangular hole based on bulk PZT film

NASA Astrophysics Data System (ADS)

Tian, Yingwei; Li, Guimiao; Yi, Zhiran; Liu, Jingquan; Yang, Bin

2018-06-01

This paper presents a high performance piezoelectric energy harvester (PEH) with a rectangular hole to work at low-frequency. This PEH used thinned bulk PZT film on flexible phosphor bronze, and its structure included piezoelectric layer, supporting layer and proof mass to reduce the resonant frequency of the device. Here, thinned bulk PZT thick film was used as piezoelectric layer due to its high piezoelectric coefficient. A Phosphor bronze was deployed as supporting layer because it had better flexibility compared to silicon and could work under high acceleration ambient with good durability. The maximum open-circuit voltage of the PEH was 15.7 V at low resonant frequency of 34.3 Hz when the input vibration acceleration was 1.5 g (g = 9.81 m/s2). Moreover, the maximum output power, the output power density and the actually current at the same acceleration were 216.66 μW, 1713.58 μW/cm3 and 170 μA, respectively, when the optimal matched resistance of 60 kΩ was connected. The fabricated PEH scavenged the vibration energy of the vacuum compression pump and generated the maximum output voltage of 1.19 V.

Solar activity and oscillation frequency splittings

NASA Technical Reports Server (NTRS)

Woodard, M. F.; Libbrecht, K. G.

1993-01-01

Solar p-mode frequency splittings, parameterized by the coefficients through order N = 12 of a Legendre polynomial expansion of the mode frequencies as a function of m/L, were obtained from an analysis of helioseismology data taken at Big Bear Solar Observatory during the 4 years 1986 and 1988-1990 (approximately solar minimum to maximum). Inversion of the even-index splitting coefficients confirms that there is a significant contribution to the frequency splittings originating near the solar poles. The strength of the polar contribution is anti correlated with the overall level or solar activity in the active latitudes, suggesting a relation to polar faculae. From an analysis of the odd-index splitting coefficients we infer an uppor limit to changes in the solar equatorial near-surface rotatinal velocity of less than 1.9 m/s (3 sigma limit) between solar minimum and maximum.

On the consideration of scaling properties of extreme rainfall in Madrid (Spain) for developing a generalized intensity-duration-frequency equation and assessing probable maximum precipitation estimates

NASA Astrophysics Data System (ADS)

Casas-Castillo, M. Carmen; Rodríguez-Solà, Raúl; Navarro, Xavier; Russo, Beniamino; Lastra, Antonio; González, Paula; Redaño, Angel

2018-01-01

The fractal behavior of extreme rainfall intensities registered between 1940 and 2012 by the Retiro Observatory of Madrid (Spain) has been examined, and a simple scaling regime ranging from 25 min to 3 days of duration has been identified. Thus, an intensity-duration-frequency (IDF) master equation of the location has been constructed in terms of the simple scaling formulation. The scaling behavior of probable maximum precipitation (PMP) for durations between 5 min and 24 h has also been verified. For the statistical estimation of the PMP, an envelope curve of the frequency factor ( k m ) based on a total of 10,194 station-years of annual maximum rainfall from 258 stations in Spain has been developed. This curve could be useful to estimate suitable values of PMP at any point of the Iberian Peninsula from basic statistical parameters (mean and standard deviation) of its rainfall series. [Figure not available: see fulltext.

Biofeedback in Partial Weight Bearing: Usability of Two Different Devices from a Patient's and Physical Therapist's Perspective.

PubMed

van Lieshout, Remko; Pisters, Martijn F; Vanwanseele, Benedicte; de Bie, Rob A; Wouters, Eveline J; Stukstette, Mirelle J

2016-01-01

Partial weight bearing is frequently instructed by physical therapists in patients after lower-limb trauma or surgery. The use of biofeedback devices seems promising to improve the patient's compliance with weight-bearing instructions. SmartStep and OpenGo-Science are biofeedback devices that provide real-time feedback. For a successful implementation, usability of the devices is a critical aspect and should be tested from a user's perspective. To describe the usability from the physical therapists' and a patients' perspective of Smartstep and OpenGo-Science to provide feedback on partial weight bearing during supervised rehabilitation of patients after lower-limb trauma or surgery. In a convergent mixed-methods design, qualitative and quantitative data were collected. Usability was subdivided into user performance, satisfaction and acceptability. Patients prescribed with partial weight bearing and their physical therapists were asked to use SmartStep and OpenGo-Science during supervised rehabilitation. Usability was qualitatively tested by a think-aloud method and a semi-structured interview and quantitatively tested by the System-Usability-Scale (SUS) and closed questions. For the qualitative data thematic content analyses were used. Nine pairs of physical therapists and their patients participated. The mean SUS scores for patients and physical therapists were for SmartStep 70 and 53, and for OpenGo-Science 79 and 81, respectively. Scores were interpreted with the Curved Grading Scale. The qualitative data showed that there were mixed views and perceptions from patients and physical therapists on satisfaction and acceptability. This study gives insight in the usability of two biofeedback devices from the patient's and physical therapist's perspective. The overall usability from both perspectives seemed to be acceptable for OpenGo-Science. For SmartStep, overall usability seemed only acceptable from the patient's perspective. The study findings could help clinicians to decide which biofeedback device is appropriate for their given situation and provide information for future development of biofeedback devices.

Engaging Community Stakeholders to Evaluate the Design, Usability, and Acceptability of a Chronic Obstructive Pulmonary Disease Social Media Resource Center

PubMed Central

Chaney, Beth; Chaney, Don; Paige, Samantha; Payne-Purvis, Caroline; Tennant, Bethany; Walsh-Childers, Kim; Sriram, PS; Alber, Julia

2015-01-01

Background Patients with chronic obstructive pulmonary disease (COPD) often report inadequate access to comprehensive patient education resources. Objective The purpose of this study was to incorporate community-engagement principles within a mixed-method research design to evaluate the usability and acceptability of a self-tailored social media resource center for medically underserved patients with COPD. Methods A multiphase sequential design (qual → QUANT → quant + QUAL) was incorporated into the current study, whereby a small-scale qualitative (qual) study informed the design of a social media website prototype that was tested with patients during a computer-based usability study (QUANT). To identify usability violations and determine whether or not patients found the website prototype acceptable for use, each patient was asked to complete an 18-item website usability and acceptability questionnaire, as well as a retrospective, in-depth, semistructured interview (quant + QUAL). Results The majority of medically underserved patients with COPD (n=8, mean 56 years, SD 7) found the social media website prototype to be easy to navigate and relevant to their self-management information needs. Mean responses on the 18-item website usability and acceptability questionnaire were very high on a scale of 1 (strongly disagree) to 5 (strongly agree) (mean 4.72, SD 0.33). However, the majority of patients identified several usability violations related to the prototype’s information design, interactive capabilities, and navigational structure. Specifically, 6 out of 8 (75%) patients struggled to create a log-in account to access the prototype, and 7 out of 8 patients (88%) experienced difficulty posting and replying to comments on an interactive discussion forum. Conclusions Patient perceptions of most social media website prototype features (eg, clickable picture-based screenshots of videos, comment tools) were largely positive. Mixed-method stakeholder feedback was used to make design recommendations, categorize usability violations, and prioritize potential solutions for improving the usability of a social media resource center for COPD patient education. PMID:25630449

SU-F-T-249: Application of Human Factors Methods: Usability Testing in the Radiation Oncology Environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Warkentin, H; Bubric, K; Giovannetti, H

2016-06-15

Purpose: As a quality improvement measure, we undertook this work to incorporate usability testing into the implementation procedures for new electronic documents and forms used by four affiliated radiation therapy centers. Methods: A human factors specialist provided training in usability testing for a team of medical physicists, radiation therapists, and radiation oncologists from four radiotherapy centers. A usability testing plan was then developed that included controlled scenarios and standardized forms for qualitative and quantitative feedback from participants, including patients. Usability tests were performed by end users using the same hardware and viewing conditions that are found in the clinical environment.more » A pilot test of a form used during radiotherapy CT simulation was performed in a single department; feedback informed adaptive improvements to the electronic form, hardware requirements, resource accessibility and the usability testing plan. Following refinements to the testing plan, usability testing was performed at three affiliated cancer centers with different vault layouts and hardware. Results: Feedback from the testing resulted in the detection of 6 critical errors (omissions and inability to complete task without assistance), 6 non-critical errors (recoverable), and multiple suggestions for improvement. Usability problems with room layout were detected at one center and problems with hardware were detected at one center. Upon amalgamation and summary of the results, three key recommendations were presented to the document’s authors for incorporation into the electronic form. Documented inefficiencies and patient safety concerns related to the room layout and hardware were presented to administration along with a request for funding to purchase upgraded hardware and accessories to allow a more efficient workflow within the simulator vault. Conclusion: By including usability testing as part of the process when introducing any new document or procedure into clinical use, associated risks can be identified and mitigated before patient care and clinical workflow are impacted.« less

Modeling of postural stability borders during heel-toe rocking.

PubMed

Murnaghan, Chantelle D; Elston, Beth; Mackey, Dawn C; Robinovitch, Stephen N

2009-08-01

To maintain balance during movements such as bending and reaching, the CNS must generate muscle forces to counteract destabilizing torques produced by gravitational (position-dependent) and inertial (acceleration-dependent) forces. This may create a trade-off between the attainable frequency and amplitude of movements. We used experiments and mathematical modeling to examine this relationship during the task of heel-toe rocking. During the experiments, participants (n=15) rocked about the ankles in the sagittal plane with maximum attainable amplitude at a frequency of 0.33 Hz or 0.66 Hz. As the frequency doubled, the maximum anterior position of the whole-body centre-of-gravity (COG) with respect to the ankle decreased by 11% of foot length (from 11.9 cm (S.D. 1.6) to 9.2 cm (S.D. 1.2); p<0.001), the minimum anterior position of the COG increased by 8% of foot length (from 1.6 cm to 3.5 cm in front on the ankle; p<0.0005), and the ankle stiffness increased from 787 Nm/rad (S.D. 156) to 1625 Nm/rad (S.D. 339). However, there was no difference between conditions in the maximum anterior position of the COP (p=0.51), the minimum anterior position of the COP (p=0.23), or the peak ankle torque (p=0.39). An inverted pendulum model driven by a rotational spring predicted the measured ankle stiffness to within 0.9% (S.D. 6.8), and the maximum anterior COG position to within 1.2% (S.D. 4.0). These results indicate that COG amplitude decreases with increasing rocking frequency, due to (a) invariability in peak ankle torque and (b) the need to allocate torque between gravitational and inertial components, the latter of which scales with the square of frequency.

Determining Usability Versus Cost and Yields of a Regional Transport

NASA Technical Reports Server (NTRS)

Gvozdenovic, Slobodan

1999-01-01

Regional transports are designed to operate on air networks having the basic characteristics of short trip distances and low density passengers/cargo, i.e. small numbers of passengers per flight. Regional transports passenger capacity is from 10 to 100 seats and operate on routes from 350 to 1000 nautical miles (nm). An air network operated by regional transports has the following characteristics: (1) connecting regional centers; (2) operating on low density passengers/cargo flow services with minimum two frequencies per day; (3) operating on high density passengers/cargo flow with more than two frequencies per day; and (4) operating supplemental services whenever market demands in order to help bigger capacity aircraft already operating the same routes. In order to meet passenger requirements providing low fares and high or required number of frequencies, airlines must constantly monitor operational costs and keep them low. It is obvious that costs of operating aircraft must be lower than yield obtained by transporting passengers and cargo. The requirement to achieve favorable yield/cost ratio must provide the answer to the question of which aircraft will best meet a specific air network. An air network is defined by the number of services, the trip distance of each service, and the number of flights (frequencies) per day and week.

Development, Construction, and Content Validation of a Questionnaire to Test Mobile Shower Commode Usability

PubMed Central

Theodoros, Deborah G.; Russell, Trevor G.

2015-01-01

Background: Usability is an emerging domain of outcomes measurement in assistive technology provision. Currently, no questionnaires exist to test the usability of mobile shower commodes (MSCs) used by adults with spinal cord injury (SCI). Objective: To describe the development, construction, and initial content validation of an electronic questionnaire to test mobile shower commode usability for this population. Methods: The questionnaire was constructed using a mixed-methods approach in 5 phases: determining user preferences for the questionnaire’s format, developing an item bank of usability indicators from the literature and judgement of experts, constructing a preliminary questionnaire, assessing content validity with a panel of experts, and constructing the final questionnaire. Results: The electronic Mobile Shower Commode Assessment Tool Version 1.0 (eMAST 1.0) questionnaire tests MSC features and performance during activities identified using a mixed-methods approach and in consultation with users. It confirms that usability is complex and multidimensional. The final questionnaire contains 25 questions in 3 sections. The eMAST 1.0 demonstrates excellent content validity as determined by a small sample of expert clinicians. Conclusion: The eMAST 1.0 tests usability of MSCs from the perspective of adults with SCI and may be used to solicit feedback during MSC design, assessment, prescription, and ongoing use. Further studies assessing the eMAST’s psychometric properties, including studies with users of MSCs, are needed. PMID:25762862

Pre-post evaluation of physicians' satisfaction with a redesigned electronic medical record system.

PubMed

Jaspers, Monique W M; Peute, Linda W P; Lauteslager, Arnaud; Bakker, Piet J M

2008-01-01

Physicians' acceptance of Electronic Medical Record Systems (EMRs) is closely related to their usability. Knowledge about end-users' opinions on usability of an EMR system may contribute to planning for the next phase of the usability cycle of the system. A demand for integration of new functionalities, such as computerized order entry and an electronic patient status led to redesign of our EMR system, which had been in use for over 8 years at the Academic Medical Center of Amsterdam. The aim of this study was to understand whether the redesigned EMR system was an improvement of the earlier EMR and which system aspects accounted for user satisfaction and which did not. We conducted a formative pre- and post usability evaluation of our former and redesigned EMR system. For the assessment of both system versions' usability, we distributed two standardized usability questionnaires among 150 clinicians who routinely had used the older EMR system and had been working with its newer version for 6 weeks. Though overall user satisfaction was relatively high for both EMR systems, screen layout and interaction structure proved less easy to work with in the newer EMR system. The new EMR system however was more appreciated because of its enhanced functionality, capabilities and likeable user-interface. The results point to a number of actions that might be useful in future usability improvement efforts of our EMR system and other EMRs.

Developing a quit smoking website that is usable by people with severe mental illnesses.

PubMed

Ferron, Joelle C; Brunette, Mary F; McHugo, Gregory J; Devitt, Timothy S; Martin, Wendy M; Drake, Robert E

2011-01-01

Evidence-based treatments may be delivered in computerized, web-based formats. This strategy can deliver the intervention consistently with minimal treatment provider time and cost. However, standard web sites may not be usable by people with severe mental illnesses who may experience cognitive deficits and low computer experience. This manuscript reports on the iterative development and usability testing of a website designed to educate and motivate adults with severe mental illnesses to engage in smoking cessation activities. Three phases of semi-structured interviews were performed with participants after they used the program and combined with information from screen-recorded usability data. T-tests compared the differences between uses of the first computer program version and a later version. Iteratively conducted usability tests demonstrated an increased ease of use from the first to the last version of the website through significant improvement in the percentage of unproductive clicking along with fewer questions asked about how to use the program. The improvement in use of the website resulted from changes such as: integrating a mouse tutorial, increasing font sizes, and increasing button sizes. The website usability recommendations provide some guidelines for interventionists developing web tools for people who experience serious psychiatric disabilities. In general, insights from the study highlight the need for thoughtful design and usability testing when creating a website for people with severe mental illness.

Usability evaluation and adaptation of the e-health Personal Patient Profile-Prostate decision aid for Spanish-speaking Latino men.

PubMed

Berry, Donna L; Halpenny, Barbara; Bosco, Jaclyn L F; Bruyere, John; Sanda, Martin G

2015-07-24

The Personal Patient Profile-Prostate (P3P), a web-based decision aid, was demonstrated to reduce decisional conflict in English-speaking men with localized prostate cancer early after initial diagnosis. The purpose of this study was to explore and enhance usability and cultural appropriateness of a Spanish P3P by Latino men with a diagnosis of prostate cancer. P3P was translated to Spanish and back-translated by three native Spanish-speaking translators working independently. Spanish-speaking Latino men with a diagnosis of localized prostate cancer, who had made treatment decisions in the past 24 months, were recruited from two urban clinical care sites. Individual cognitive interviews were conducted by two bilingual research assistants as each participant used the Spanish P3P. Notes of user behavior, feedback, and answers to direct questions about comprehension, usability and perceived usefulness were analyzed and categorized. Seven participants with a range of education levels identified 25 unique usability issues in navigation, content comprehension and completeness, sociocultural appropriateness, and methodology. Revisions were prioritized to refine the usability and cultural and linguistic appropriateness of the decision aid. Usability issues were discovered that are potential barriers to effective decision support. Successful use of decision aids requires adaptation and testing beyond translation. Our findings led to revisions further refining the usability and linguistic and cultural appropriateness of Spanish P3P.

Dynamic Behaviour and Seismic Response of Ground Supported Cylindrical Water Tanks

NASA Astrophysics Data System (ADS)

Asha, Joseph; Glory, Joseph

2018-05-01

Liquid storage tank such as in water distribution systems, petroleum plants etc., constitute a vital component of life line systems. Reducing earthquake effects on liquid storage tanks, to minimize the environmental and economic impact of these effects, have always been an important engineering concern. In this paper, the dynamic behavior of cylindrical ground supported concrete water tanks with different aspect ratios is investigated using finite element software ANSYS. The natural frequencies and modal responses are obtained for impulsive and convective modes of vibration. The natural frequency of vibration of the tank is observed to be the lowest at maximum water depth. The fundamental impulsive frequency increases as water level reduces and for water level less than 1/3 of tank height, there is significantly no change in impulsive frequency. The effect of wall flexibility on dynamic behavior of the tank is investigated by performing the modal analysis of flexible and rigid tanks. For a partially filled tank, the results of the present study are of significant relevance. The response of the tank to the transient loading as horizontal ground motion of El Centro earthquake is studied for various water heights. As the height of water on the tank increases, the ultimate maximum seismic response parameters are also observed to be increased. The location of maximum hoop stress varies in accordance with the variations in input ground motion and water fill condition whereas shear and bending moment are maximum at the base.

Evaluation of the reliability, usability, and applicability of AMSTAR, AMSTAR 2, and ROBIS: protocol for a descriptive analytic study.

PubMed

Gates, Allison; Gates, Michelle; Duarte, Gonçalo; Cary, Maria; Becker, Monika; Prediger, Barbara; Vandermeer, Ben; Fernandes, Ricardo M; Pieper, Dawid; Hartling, Lisa

2018-06-13

Systematic reviews (SRs) of randomised controlled trials (RCTs) can provide the best evidence to inform decision-making, but their methodological and reporting quality varies. Tools exist to guide the critical appraisal of quality and risk of bias in SRs, but evaluations of their measurement properties are limited. We will investigate the interrater reliability (IRR), usability, and applicability of A MeaSurement Tool to Assess systematic Reviews (AMSTAR), AMSTAR 2, and Risk Of Bias In Systematic reviews (ROBIS) for SRs in the fields of biomedicine and public health. An international team of researchers at three collaborating centres will undertake the study. We will use a random sample of 30 SRs of RCTs investigating therapeutic interventions indexed in MEDLINE in February 2014. Two reviewers at each centre will appraise the quality and risk of bias in each SR using AMSTAR, AMSTAR 2, and ROBIS. We will record the time to complete each assessment and for the two reviewers to reach consensus for each SR. We will extract the descriptive characteristics of each SR, the included studies, participants, interventions, and comparators. We will also extract the direction and strength of the results and conclusions for the primary outcome. We will summarise the descriptive characteristics of the SRs using means and standard deviations, or frequencies and proportions. To test for interrater reliability between reviewers and between the consensus agreements of reviewer pairs, we will use Gwet's AC 1 statistic. For comparability to previous evaluations, we will also calculate weighted Cohen's kappa and Fleiss' kappa statistics. To estimate usability, we will calculate the mean time to complete the appraisal and to reach consensus for each tool. To inform applications of the tools, we will test for statistical associations between quality scores and risk of bias judgments, and the results and conclusions of the SRs. Appraising the methodological and reporting quality of SRs is necessary to determine the trustworthiness of their conclusions. Which tool may be most reliably applied and how the appraisals should be used is uncertain; the usability of newly developed tools is unknown. This investigation of common (AMSTAR) and newly developed (AMSTAR 2, ROBIS) tools will provide empiric data to inform their application, interpretation, and refinement.

Usability Evaluation of the Student Centered e-Learning Environment

ERIC Educational Resources Information Center

Junus, Inas Sofiyah; Santoso, Harry Budi; Isal, R. Yugo K.; Utomo, Andika Yudha

2015-01-01

Student Centered e-Learning Environment (SCeLE) has substantial roles to support learning activities at Faculty of Computer Science, Universitas Indonesia (Fasilkom UI). Although it has been utilized for about 10 years, the usability aspect of SCeLE as an e-Learning system has not been evaluated. Therefore, the usability aspects of SCeLE Fasilkom…

Patterns for Success: A Lesson in Usable Design from U.S. Patent Records.

ERIC Educational Resources Information Center

Durack, Katherine T.

1997-01-01

Investigates the design history of women's household sewing patterns as that history is recorded in United States Patent Records. Finds that the history of home sewing patterns illustrates a key aspect of usable design: the interrelationship between a device and its documentation and the way changes to both enhance overall product usability. (RS)

Usability Assessment of Educational Software by Students: Case of "?Pón-Ìm?`" in Osun State, Nigeria

ERIC Educational Resources Information Center

Tijani, O. K.

2016-01-01

This study investigated usability of educational software: case of "?pón-Ìm?`" in Osun state, Nigeria. Specifically, the study investigated influences of gender and school locations on students' assessment of "?pón-Ìm?`" Technology Enhanced Learning System (OTELS) based on selected usability parameters. 701 students were…

An Examination of Usability of a Virtual Environment for Students Enrolled in a College of Agriculture

ERIC Educational Resources Information Center

Murphrey, Theresa Pesl; Rutherford, Tracy A.; Doerfert, David L.; Edgar, Leslie D.; Edgar, Don W.

2014-01-01

Educational technology continues to expand with multi-user virtual environments (e.g., Second Life™) being the latest technology. Understanding a virtual environment's usability can enhance educational planning and effective use. Usability includes the interaction quality between an individual and the item being assessed. The purpose was to assess…

User-Centered Design and Usability Testing of a Web Site: An Illustrative Case Study.

ERIC Educational Resources Information Center

Corry, Michael D.; Frick, Theodore W.; Hansen, Lisa

1997-01-01

Presents an overview of user-centered design and usability testing. Describes a Web site evaluation project at a university, the iterative process of rapid prototyping and usability testing, and how the findings helped to improve the design. Discusses recommendations for university Web site design and reflects on problems faced in usability…

The Influence of Product Aesthetics and User State in Usability Testing

ERIC Educational Resources Information Center

Sauer, Juergen; Sonderegger, Andreas

2011-01-01

An empirical study examined the effects of two influencing factors in usability tests on user performance and usability ratings. Product aesthetics (high vs. low) as the main independent factor and prior usage event (positive vs. negative) as a subsidiary independent factor were varied in a between-participants design. 60 participants took part in…

Evaluating the Usability of a Museum Web Site.

ERIC Educational Resources Information Center

Harms, Ilse; Schweibenz, Werner

This paper presents a research project conducted by the Department of Information Science in cooperation with the Saarland Museum, the art museum of the Federal State of Saarland, Germany. The study had two aims. The first was to evaluate some methods of usability engineering for the Web, and the second was to evaluate the usability of the…

A Usability Study of Users' Perceptions toward a Multimedia Computer-Assisted Learning Tool for Neuroanatomy

ERIC Educational Resources Information Center

Gould, Douglas J.; Terrell, Mark A.; Fleming, Jo

2008-01-01

This usability study evaluated users' perceptions of a multimedia prototype for a new e-learning tool: Anatomy of the Central Nervous System: A Multimedia Course. Usability testing is a collection of formative evaluation methods that inform the developmental design of e-learning tools to maximize user acceptance, satisfaction, and adoption.…

The Relationship between National Culture and the Usability of an E-Learning System

ERIC Educational Resources Information Center

Adeoye, Blessing; Wentling, Rose Mary

2007-01-01

The purpose of this study was to investigate possible relationships between national culture and the usability of an e-learning system. The theoretical frameworks that were used to guide this study were Hofstede's (1980) cultural dimensions, and Nielson's (1993) usability attributes. The sample for this study was composed of 24 international…

Navigation in the electronic health record: A review of the safety and usability literature.

PubMed

Roman, Lisette C; Ancker, Jessica S; Johnson, Stephen B; Senathirajah, Yalini

2017-03-01

Inefficient navigation in electronic health records has been shown to increase users' cognitive load, which may increase potential for errors, reduce efficiency, and increase fatigue. However, navigation has received insufficient recognition and attention in the electronic health record (EHR) literature as an independent construct and contributor to overall usability. Our aims in this literature review were to (1) assess the prevalence of navigation-related topics within the EHR usability and safety research literature, (2) categorize types of navigation actions within the EHR, (3) capture relationships between these navigation actions and usability principles, and (4) collect terms and concepts related to EHR navigation. Our goal was to improve access to navigation-related research in usability. We applied scoping literature review search methods with the assistance of a reference librarian to identify articles published since 1996 that reported evaluation of the usability or safety of an EHR user interface via user test, analytic methods, or inspection methods. The 4336 references collected from MEDLINE, EMBASE, Engineering Village, and expert referrals were de-duplicated and screened for relevance, and navigation-related concepts were abstracted from the 21 articles eligible for review using a standard abstraction form. Of the 21 eligible articles, 20 (95%) mentioned navigation in results and discussion of usability evaluations. Navigation between pages of the EHR was the more frequently documented type of navigation (86%) compared to navigation within a single page (14%). Navigation actions (e.g., scrolling through a medication list) were frequently linked to specific usability heuristic violations, among which flexibility and efficiency of use, recognition rather than recall, and error prevention were most common. Discussion of navigation was prevalent in results across all types of evaluation methods among the articles reviewed. Navigating between multiple screens was frequently identified as a usability barrier. The lack of standard terminology created some challenges to identifying and comparing articles. We observed that usability researchers are frequently capturing navigation-related issues even in articles that did not explicitly state navigation as a focus. Capturing and synthesizing the literature on navigation is challenging because of the lack of uniform vocabulary. Navigation is a potential target for normative recommendations for improved interaction design for safer systems. Future research in this domain, including development of normative recommendations for usability design and evaluation, will be facilitated by development of a standard terminology for describing EHR navigation. Copyright © 2017 Elsevier Inc. All rights reserved.

Determination of sound types and source levels of airborne vocalizations by California sea lions, Zalophus californianus, in rehabilitation at the Marine Mammal Center in Sausalito, California

NASA Astrophysics Data System (ADS)

Schwalm, Afton Leigh

California sea lions (Zalophus californianus) are a highly popular and easily recognized marine mammal in zoos, aquariums, circuses, and often seen by ocean visitors. They are highly vocal and gregarious on land. Surprisingly, little research has been performed on the vocalization types, source levels, acoustic properties, and functions of airborne sounds used by California sea lions. This research on airborne vocalizations of California sea lions will advance the understanding of this aspect of California sea lions communication, as well as examine the relationship between health condition and acoustic behavior. Using a PhillipsRTM digital recorder with attached microphone and a calibrated RadioShackRTM sound pressure level meter, acoustical data were recorded opportunistically on California sea lions during rehabilitation at The Marine Mammal Center in Sausalito, CA. Vocalizations were analyzed using frequency, time, and amplitude variables with Raven Pro: Interactive Sound Analysis Software Version 1.4 (The Cornell Lab of Ornithology, Ithaca, NY). Five frequency, three time, and four amplitude variables were analyzed for each vocalization. Differences in frequency, time, and amplitude variables were not significant by sex. The older California sea lion group produced vocalizations that were significantly lower in four frequency variables, significantly longer in two time variables, significantly higher in calibrated maximum and minimum amplitude variables, and significantly lower in frequency at maximum and minimum amplitude compared with pups. Six call types were identified: bark, goat, growl/grumble, bark/grumble, bark/growl, and grumble/moan. The growl/grumble call was higher in dominant beginning, ending, and minimum frequency, as well as in the frequency at maximum amplitude compared with the bark, goat, bark/grumble calls in the first versus last vocalization sample. The goat call was significantly higher in first harmonic interval than any other call type in the all vocalizations sample. The "fate" of a sea lion was categorized as: released, placed at another facility, remained at TMMC, euthanized, or died. To determine if acoustic features could be used to assess the recovery of a pup, the acoustic features of a pup's first recorded vocalization were compared with the frequency, time, and amplitude of the last vocalization recorded (i.e., before it was released or placed at another facility). In addition, all first vocalizations were pooled and all last vocalizations were pooled for acoustic analysis, regardless of their fate. Released pups had shorter duration calls, a greater first harmonic interval, and a higher dominant maximum frequency than either pups that died or pups remaining at TMMC. Released pups had a higher frequency at maximum and minimum amplitude compared to dead and remaining pups. Pups that died had significantly lower dominant ending frequency and a lower dominant minimum frequency than released or remaining pups. These results were supported by other studies on different species of otariids, phocids, and cetaceans. The preliminary analyses presented in this thesis holds promise that with additional data acoustic features of California sea lion airborne vocalizations could indicate sex, age, and possibly health condition or the potential for release.

Applying User-Centered Design Methods to the Development of an mHealth Application for Use in the Hospital Setting by Patients and Care Partners.

PubMed

Couture, Brittany; Lilley, Elizabeth; Chang, Frank; DeBord Smith, Ann; Cleveland, Jessica; Ergai, Awatef; Katsulis, Zachary; Benneyan, James; Gershanik, Esteban; Bates, David W; Collins, Sarah A

2018-04-01

 Developing an optimized and user-friendly mHealth application for patients and family members in the hospital environment presents unique challenges given the diverse patient population and patients' various states of well-being.  This article describes user-centered design methods and results for developing the patient and family facing user interface and functionality of MySafeCare, a safety reporting tool for hospitalized patients and their family members.  Individual and group usability sessions were conducted with specific testing scenarios for participants to follow to test the usability and functionality of the tool. Participants included patients, family members, and Patient and Family Advisory Council (PFAC) members. Engagement rounds were also conducted on study units and lessons learned provided additional information to the usability work. Usability results were aligned with Nielsen's Usability Heuristics.  Eleven patients and family members and 25 PFAC members participated in usability testing and over 250 patients and family members were engaged during research team rounding. Specific themes resulting from the usability testing sessions influenced the changes made to the user interface design, workflow functionality, and terminology.  User-centered design should focus on workflow functionality, terminology, and user interface issues for mHealth applications. These themes illustrated issues aligned with four of Nielsen's Usability Heuristics: match between system and the real world, consistency and standards, flexibility and efficiency of use, and aesthetic and minimalist design. We identified workflow and terminology issues that may be specific to the use of an mHealth application focused on safety and used by hospitalized patients and their families. Schattauer GmbH Stuttgart.

How you spend your pennies ... factors affecting the efficiency of human waste disposal systems (re-usable and disposable) and their cost.

PubMed

Rollnick, M

1991-05-01

Both re-usable and disposable systems have their merits and problems. The disposable system, being fully integrated, appears to be steadily gaining market share compared with the re-usable system. Since its introduction, the success of the re-usable system has been limited by the use of pans not designed for automatic processing. Where the 'perfection' pan has been superseded by 'open' shaped receptacles and those used in commode chairs, cleaning effectiveness can be improved by a factor of 10. For this and other reasons, nursing involvement in the re-usable system can be high while the 'perfection' pan is in use. A work study exercise to compare nursing involvement in re-usable and disposable systems is under way. When selecting a human waste disposal system for any site, it is vital that all disciplines discuss and decide objectives. The equipment usage, space, site conditions, availability and quality of supplies (eg water, electricity), the costs of maintenance, nursing time and other expenditure must be considered. The disposable system is capable of high process rates (more than double that of the fastest re-usable system). Its capital cost is currently about 1,000 pounds less than an average re-usable system, but in the busiest wards, revenue costs may be higher. In such wards the space for disposable receptacle storage can be as much as five to ten times machine volume. The design of macerators is generally simpler (having less components) than washer-disinfectors. Monitoring and maintenance involvement are likewise expected to be lower, particularly in hospitals with modern drainage systems.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of heuristic and cognitive walkthrough usability evaluation methods for evaluating health information systems.

PubMed

Khajouei, Reza; Zahiri Esfahani, Misagh; Jahani, Yunes

2017-04-01

There are several user-based and expert-based usability evaluation methods that may perform differently according to the context in which they are used. The objective of this study was to compare 2 expert-based methods, heuristic evaluation (HE) and cognitive walkthrough (CW), for evaluating usability of health care information systems. Five evaluators independently evaluated a medical office management system using HE and CW. We compared the 2 methods in terms of the number of identified usability problems, their severity, and the coverage of each method. In total, 156 problems were identified using the 2 methods. HE identified a significantly higher number of problems related to the "satisfaction" attribute ( P  = .002). The number of problems identified using CW concerning the "learnability" attribute was significantly higher than those identified using HE ( P  = .005). There was no significant difference between the number of problems identified by HE, based on different usability attributes ( P  = .232). Results of CW showed a significant difference between the number of problems related to usability attributes ( P  < .0001). The average severity of problems identified using CW was significantly higher than that of HE ( P  < .0001). This study showed that HE and CW do not differ significantly in terms of the number of usability problems identified, but they differ based on the severity of problems and the coverage of some usability attributes. The results suggest that CW would be the preferred method for evaluating systems intended for novice users and HE for users who have experience with similar systems. However, more studies are needed to support this finding. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Quantifying usability: an evaluation of a diabetes mHealth system on effectiveness, efficiency, and satisfaction metrics with associated user characteristics.

PubMed

Georgsson, Mattias; Staggers, Nancy

2016-01-01

Mobile health (mHealth) systems are becoming more common for chronic disease management, but usability studies are still needed on patients' perspectives and mHealth interaction performance. This deficiency is addressed by our quantitative usability study of a mHealth diabetes system evaluating patients' task performance, satisfaction, and the relationship of these measures to user characteristics. We used metrics in the International Organization for Standardization (ISO) 9241-11 standard. After standardized training, 10 patients performed representative tasks and were assessed on individual task success, errors, efficiency (time on task), satisfaction (System Usability Scale [SUS]) and user characteristics. Tasks of exporting and correcting values proved the most difficult, had the most errors, the lowest task success rates, and consumed the longest times on task. The average SUS satisfaction score was 80.5, indicating good but not excellent system usability. Data trends showed males were more successful in task completion, and younger participants had higher performance scores. Educational level did not influence performance, but a more recent diabetes diagnosis did. Patients with more experience in information technology (IT) also had higher performance rates. Difficult task performance indicated areas for redesign. Our methods can assist others in identifying areas in need of improvement. Data about user background and IT skills also showed how user characteristics influence performance and can provide future considerations for targeted mHealth designs. Using the ISO 9241-11 usability standard, the SUS instrument for satisfaction and measuring user characteristics provided objective measures of patients' experienced usability. These could serve as an exemplar for standardized, quantitative methods for usability studies on mHealth systems. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association.

Towards Usable E-Health. A Systematic Review of Usability Questionnaires.

PubMed

Sousa, Vanessa E C; Dunn Lopez, Karen

2017-05-10

The use of e-health can lead to several positive outcomes. However, the potential for e-health to improve healthcare is partially dependent on its ease of use. In order to determine the usability for any technology, rigorously developed and appropriate measures must be chosen. To identify psychometrically tested questionnaires that measure usability of e-health tools, and to appraise their generalizability, attributes coverage, and quality. We conducted a systematic review of studies that measured usability of e-health tools using four databases (Scopus, PubMed, CINAHL, and HAPI). Non-primary research, studies that did not report measures, studies with children or people with cognitive limitations, and studies about assistive devices or medical equipment were systematically excluded. Two authors independently extracted information including: questionnaire name, number of questions, scoring method, item generation, and psychometrics using a data extraction tool with pre-established categories and a quality appraisal scoring table. Using a broad search strategy, 5,558 potentially relevant papers were identified. After removing duplicates and applying exclusion criteria, 35 articles remained that used 15 unique questionnaires. From the 15 questionnaires, only 5 were general enough to be used across studies. Usability attributes covered by the questionnaires were: learnability (15), efficiency (12), and satisfaction (11). Memorability (1) was the least covered attribute. Quality appraisal showed that face/content (14) and construct (7) validity were the most frequent types of validity assessed. All questionnaires reported reliability measurement. Some questionnaires scored low in the quality appraisal for the following reasons: limited validity testing (7), small sample size (3), no reporting of user centeredness (9) or feasibility estimates of time, effort, and expense (7). Existing questionnaires provide a foundation for research on e-health usability. However, future research is needed to broaden the coverage of the usability attributes and psychometric properties of the available questionnaires.

Usability and feasibility of health IT interventions to enhance Self-Care for Lymphedema Symptom Management in breast cancer survivors.

PubMed

Fu, Mei R; Axelrod, Deborah; Guth, Amber A; Wang, Yao; Scagliola, Joan; Hiotis, Karen; Rampertaap, Kavita; El-Shammaa, Nardin

2016-09-01

The-Optimal-Lymph-Flow health IT system (TOLF) is a patient-centered, web-and-mobile-based educational and behavioral health IT system focusing on safe, innovative, and pragmatic self-care strategies for lymphedema symptom management. The purpose of this study was to evaluate usability, feasibility, and acceptability of TOLF among the end-user of breast cancer survivors. Two types of usability testing were completed with 30 breast cancer survivors: heuristic evaluation and end-user testing. Each participant was asked to think aloud while completing a set of specified tasks designed to explicate and freely explore the system features. A heuristic evaluation checklist, the Perceived Ease of Use and Usefulness Questionnaire, and The Post Study System Usability Questionnaire were used to evaluate usability of the system. Open-ended questions were used to gather qualitative data. Quantitative data were analyzed using descriptive statistics and qualitative data were summarized thematically. Breast cancer survivors were very satisfied with the system: 90% (n = 27) rated the system having no usability problems; 10% (n = 3) noted minor cosmetic problems: spelling errors or text font size. The majority of participants 96.6% (n = 29) strongly agreed that the system was easy to use and effective in helping to learn about lymphedema, symptoms and self-care strategies. Themes from the qualitative data included empowerment, high quality information, loving avatar simulation videos, easy accessibility, and user-friendliness. This usability study provided evidence on breast cancer survivor's acceptance and highly positive evaluation of TOLF's usability as well as feasibility of using technologically-driven delivery model to enhance self-care strategies for lymphedema symptom management.

Quantifying usability: an evaluation of a diabetes mHealth system on effectiveness, efficiency, and satisfaction metrics with associated user characteristics

PubMed Central

Staggers, Nancy

2016-01-01

Objective Mobile health (mHealth) systems are becoming more common for chronic disease management, but usability studies are still needed on patients’ perspectives and mHealth interaction performance. This deficiency is addressed by our quantitative usability study of a mHealth diabetes system evaluating patients’ task performance, satisfaction, and the relationship of these measures to user characteristics. Materials and Methods We used metrics in the International Organization for Standardization (ISO) 9241-11 standard. After standardized training, 10 patients performed representative tasks and were assessed on individual task success, errors, efficiency (time on task), satisfaction (System Usability Scale [SUS]) and user characteristics. Results Tasks of exporting and correcting values proved the most difficult, had the most errors, the lowest task success rates, and consumed the longest times on task. The average SUS satisfaction score was 80.5, indicating good but not excellent system usability. Data trends showed males were more successful in task completion, and younger participants had higher performance scores. Educational level did not influence performance, but a more recent diabetes diagnosis did. Patients with more experience in information technology (IT) also had higher performance rates. Discussion Difficult task performance indicated areas for redesign. Our methods can assist others in identifying areas in need of improvement. Data about user background and IT skills also showed how user characteristics influence performance and can provide future considerations for targeted mHealth designs. Conclusion Using the ISO 9241-11 usability standard, the SUS instrument for satisfaction and measuring user characteristics provided objective measures of patients’ experienced usability. These could serve as an exemplar for standardized, quantitative methods for usability studies on mHealth systems. PMID:26377990

Surface waters of Elk Creek basin in southwestern Oklahoma

USGS Publications Warehouse

Westfall, A.O.

1963-01-01

The purpose of this study is to (1) determine the average discharge during a period that is representative of average streamflow conditions, (2) determine the range of discharge, and (3) determine the storage required to supplement natural flows during drought periods. Elk Creek drains 587 square miles of the North Fork Red River basin. The climate is subhumid, and precipitation averages about 23 inches per year. The average discharge at the gaging station near Hobart is 50 cfs (cubic feet per second) or 36,200 acre-feet per year during a 19-year base period, water years 1938-56. The yearly average discharge ranged from 4.6 cfs in 1940 to 146 cfs in 1957. Maximum runoff generally occurs during May and June. The maximum monthly runoff was 64,520 acre-feet in May 1957. The maximum yearly runoff was 105,500 acre-feet in 1957. There is no sustained base flow in the basin. Severe droughts occurred in 1938-40 and 1952-56. The most extended drought occurred from June 1951 to March 1957, during which time there was a prolonged period of no flow of 182 days in 1954-55. A usable storage of 28,000 acre-feet would have been required to provide a regulated discharge of 1,500 acre-feet per month throughout these drought periods. (available as photostat copy only)

Using iMCFA to Perform the CFA, Multilevel CFA, and Maximum Model for Analyzing Complex Survey Data.

PubMed

Wu, Jiun-Yu; Lee, Yuan-Hsuan; Lin, John J H

2018-01-01

To construct CFA, MCFA, and maximum MCFA with LISREL v.8 and below, we provide iMCFA (integrated Multilevel Confirmatory Analysis) to examine the potential multilevel factorial structure in the complex survey data. Modeling multilevel structure for complex survey data is complicated because building a multilevel model is not an infallible statistical strategy unless the hypothesized model is close to the real data structure. Methodologists have suggested using different modeling techniques to investigate potential multilevel structure of survey data. Using iMCFA, researchers can visually set the between- and within-level factorial structure to fit MCFA, CFA and/or MAX MCFA models for complex survey data. iMCFA can then yield between- and within-level variance-covariance matrices, calculate intraclass correlations, perform the analyses and generate the outputs for respective models. The summary of the analytical outputs from LISREL is gathered and tabulated for further model comparison and interpretation. iMCFA also provides LISREL syntax of different models for researchers' future use. An empirical and a simulated multilevel dataset with complex and simple structures in the within or between level was used to illustrate the usability and the effectiveness of the iMCFA procedure on analyzing complex survey data. The analytic results of iMCFA using Muthen's limited information estimator were compared with those of Mplus using Full Information Maximum Likelihood regarding the effectiveness of different estimation methods.

Influence of the oscillation frequency of different side-to-side toothbrushes on noncontact biofilm removal.

PubMed

Schmidt, Julia C; Astasov-Frauenhoffer, Monika; Waltimo, Tuomas; Weiger, Roland; Walter, Clemens

2018-01-22

The objective of this study was to investigate the influence of different oscillation frequencies of three powered toothbrushes with side-to-side action for noncontact biofilm removal in an artificial interdental space model. A three-species biofilm (Porphyromonas gingivalis, Fusobacterium nucleatum and Streptococcus sanguinis) was formed in vitro on protein-coated titanium disks using a flow chamber system combined with a static biofilm growth model. The oscillation frequencies of three commercial side-to-side toothbrushes were evaluated by means of a dose response. The frequency was decreased in steps (100, 85, 70, 55, and 40%). Subsequently, the biofilm-coated substrates were exposed to the side-to-side toothbrushes. The biofilm volumes were measured using volumetric analyses (Imaris 8.1.2) with confocal laser scanning microscope images (Zeiss LSM700). Compared to maximum oscillation frequency (100%), lower oscillation frequencies (up to 40%) resulted in reduced median percentages of biofilm reduction (median biofilm reduction up to 53% for maximum oscillation frequency, and up to 13% for 40% oscillation frequency) (p ≥ 0.03). In addition, decreasing the oscillation frequencies of the side-to-side toothbrushes showed an enhanced variety in the results of repeated experiments. The oscillation frequency of the tested side-to-side toothbrushes affected the biofilm reduction in an interdental space model. Within a toothbrush, higher oscillation frequencies may lead to beneficial effects on interdental biofilm removal by noncontact brushing.

40 CFR Table 3 to Subpart Hhh of... - Operating Parameters To Be Monitored and Minimum Measurement and Recording Frequencies

Code of Federal Regulations, 2010 CFR

2010-07-01

... rural HMIWI HMIWI a with dry scrubber followed by fabric filter HMIWI a with wet scrubber HMIWI a with dry scrubber followed by fabric filter and wet scrubber Maximum operating parameters: Maximum charge rate Once per charge Once per charge ✔ ✔ ✔ ✔ Maximum fabric filter inlet temperature Continuous Once...

Useful to Usable (U2U): Transforming Climate Variability and Change Information for Cereal Crop Producers

NASA Astrophysics Data System (ADS)

Niyogi, D.; Andresen, J.

2011-12-01

Corn and soybean production contributes over $100 billion annually to the U.S. economy, most of which comes from the intensely cultivated corn-belt region of the Midwest. Successful crop production in this region is highly dependent on favorable temperatures and appropriate precipitation patters, making this industry vulnerable to changes in climate patterns. Though predictive models are constantly improving, there are gaps in our understanding of how different management practices can be used to help farmers adapt to changes in climate while maintaining economic viability. Furthermore, currently available tools and models are not meeting producers' needs, and little is known about the types of information they would like to access. Useful to Usable (U2U): Transforming Climate Variability and Change Information for Cereal Crop Producers is an integrated research and extension project that seeks to improve the resilience and profitability of farms in the North Central Region amid variable climate change through the development and dissemination of improved decision support tools, resource materials, and training. The goal is to work closely with producers to help them make better long-term plans on what, when and where to plant, and also how to manage crops for maximum yields and minimum environmental damage. The U2U team is composed of a uniquely qualified group of climatologists, crop modelers, agronomists, economists, and social scientists from 10 partner universities across the Midwest. Over the span of 5 years, collaborators will complete tasks associated with 5 objectives that will enhance the usability of climate information for the agricultural community and lead to more sustainable farming operations. First the team will produce research on the biophysical and economic impacts of different climate scenarios on corn and soybean yields in the North Central Region (objective 1) and conduct complementary research to understand how producers and advisors are likely to use this information (objective 2). Based on these findings, decision support tools (DSTs) and training materials will be developed to effectively deliver climate information to stakeholders (objective 3). Next, DSTs will be piloted in a four-state region (Indiana, Iowa, Nebraska, and Michigan) to help improve tools and evaluate effectiveness (objective 4). After several iterations with stakeholders to ensure the usability and utility of the tools, the program will be extended to all twelve states in the region (objective 5). Decision support tools, along with training products, surveys, feedback mechanisms and collaborative social tools, will be supported using the NSF-funded and Purdue University developed HUBzero web-based technology.

Evidence-based Heuristics for Evaluating Demands on eHealth Literacy and Usability in a Mobile Consumer Health Application.

PubMed

Monkman, Helen; Griffith, Janessa; Kushniruk, Andre W

2015-01-01

Heuristic evaluations have proven to be valuable for identifying usability issues in systems. Commonly used sets of heuritics exist; however, they may not always be the most suitable, given the specific goal of the analysis. One such example is seeking to evaluate the demands on eHealth literacy and usability of consumer health information systems. In this study, eight essential heuristics and three optional heuristics subsumed from the evidence on eHealth/health literacy and usability were tested for their utility in assessing a mobile blood pressure tracking application (app). This evaluation revealed a variety of ways the design of the app could both benefit and impede users with limited eHealth literacy. This study demonstrated the utility of a low-cost, single evaluation approach for identifying both eHealth literacy and usability issues based on existing evidence in the literature.

Usability Laboratory Test of a Novel Mobile Homecare Application with Experienced Home Help Service Staff

PubMed Central

Scandurra, I; Hägglund, M; Koch, S; Lind, M

2008-01-01

Using participatory design, we developed and deployed a mobile Virtual Health Record (VHR) on a personal digital assistant (PDA) together with experienced homecare staff. To assess transferability to a second setting and usability when used by novice users with limited system education the application was tested in a usability lab. Eight participants from another homecare district performed tasks related to daily homecare work using the VHR. Test protocols were analyzed with regard to effectiveness, potential usability problems and user satisfaction. Usability problems having impact on system performance and contextual factors affecting system transferability were uncovered. Questionnaires revealed that the participants frequently used computers, but never PDAs. Surprisingly there were only minor differences in input efficiency between novice and experienced users. The participants were overall satisfied with the application. However, transfer to another district can not be performed, unless by means of careful field observations of contextual differences. PMID:19415140

Development and evaluation of RAMP I - a practitioner's tool for screening of musculoskeletal disorder risk factors in manual handling.

PubMed

Lind, Carl Mikael; Forsman, Mikael; Rose, Linda Maria

2017-10-16

RAMP I is a screening tool developed to support practitioners in screening for work-related musculoskeletal disorder risk factors related to manual handling. RAMP I, which is part of the RAMP tool, is based on research-based studies combined with expert group judgments. More than 80 practitioners participated in the development of RAMP I. The tool consists of dichotomous assessment items grouped into seven categories. Acceptable reliability was found for a majority of the assessment items for 15 practitioners who were given 1 h of training. The usability evaluation points to RAMP I being usable for screening for musculoskeletal disorder risk factors, i.e., usable for assessing risks, being usable as a decision base, having clear results and that the time needed for an assessment is acceptable. It is concluded that RAMP I is a usable tool for practitioners.