61 research outputs found

    An Empirical Study Comparing Unobtrusive Physiological Sensors for Stress Detection in Computer Work.

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    Several unobtrusive sensors have been tested in studies to capture physiological reactions to stress in workplace settings. Lab studies tend to focus on assessing sensors during a specific computer task, while in situ studies tend to offer a generalized view of sensors' efficacy for workplace stress monitoring, without discriminating different tasks. Given the variation in workplace computer activities, this study investigates the efficacy of unobtrusive sensors for stress measurement across a variety of tasks. We present a comparison of five physiological measurements obtained in a lab experiment, where participants completed six different computer tasks, while we measured their stress levels using a chest-band (ECG, respiration), a wristband (PPG and EDA), and an emerging thermal imaging method (perinasal perspiration). We found that thermal imaging can detect increased stress for most participants across all tasks, while wrist and chest sensors were less generalizable across tasks and participants. We summarize the costs and benefits of each sensor stream, and show how some computer use scenarios present usability and reliability challenges for stress monitoring with certain physiological sensors. We provide recommendations for researchers and system builders for measuring stress with physiological sensors during workplace computer use

    A usability study of physiological measurement in school using wearable sensors

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    Measuring psychophysiological signals of adolescents using unobtrusive wearable sensors may contribute to understanding the development of emotional disorders. This study investigated the feasibility of measuring high quality physiological data and examined the validity of signal processing in a school setting. Among 86 adolescents, a total of more than 410 h of electrodermal activity (EDA) data were recorded using a wrist-worn sensor with gelled electrodes and over 370 h of heart rate data were recorded using a chest-strap sensor. The results support the feasibility of monitoring physiological signals at school. We describe specific challenges and provide recommendations for signal analysis, including dealing with invalid signals due to loose sensors, and quantization noise that can be caused by limitations in analog-to-digital conversion in wearable devices and be mistaken as physiological responses. Importantly, our results show that using toolboxes for automatic signal preprocessing, decomposition, and artifact detection with default parameters while neglecting differences between devices and measurement contexts yield misleading results. Time courses of students' physiological signals throughout the course of a class were found to be clearer after applying our proposed preprocessing steps

    Towards Affective Chronometry:Exploring Smart Materials and Actuators for Real-time Representations of Changes in Arousal

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    Increasing HCI work on affective interfaces aimed to capture and communicate users’ emotions in order to support self-understanding. While most such interfaces employ traditional screen-based displays, more novel approaches have started to investigate smart materials and actuators based prototypes. In this paper, we describe our exploration of smart materials and actuators leveraging their temporal qualities as well as common metaphors for real-time representation of changes in arousal through visual and haptic modalities. This exploration provided rationale for the design and implementation of six novel wrist-worn prototypes evaluated with 12 users who wore them over 2 days. Our findings describe how people use them in daily life, and how their material-driven qualities such as responsiveness, duration, rhythm, inertia, aliveness and range shape people’s emotion identification, attribution, and regulation. Our findings led to four design implications including support for affective chronometry for both raise and decay time of emotional response, design for slowness, and for expressiveness

    Energy: A continuing bibliography with indexes, issue 39

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    This bibliography lists 1377 reports, articles and other documents introduced into the NASA scientific and technical information system from July 1, 1983 through September 30, 1983

    USCID water management conference

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    Presented at Upgrading technology and infrastructure in a finance-challenged economy: a USCID water management conference held on March 23-26, 2010 in Sacramento, California.Due to multiple impacts being placed on the James Irrigation District (District) water supply, a study was performed to understand if the District could sustain its current operations. It was determined that the practices could continue but it would require capitally intensive improvements to the Districts infrastructure. Planned improvements include the construction of recharge basins for sustainability, installation of up to 16 groundwater wells and pumps, basin construction, pipeline installation, and construction of flow control and pumping structures. The improvements were estimated to cost approximately 9,000,000;acosttoohighfortheDistricttofundontheirown.Becauseoftheurgencyoftheproject,TheDistrictexploredmultipleopportunitiestofundtheproject.Thisincludedapplyingforloans,applyingforgrants,raisingwaterrates,andraisinglandassessments;allatthesametime.ToobtainloanmoneytheDistrictappliedforfundsthroughProposition82,distributedbytheDepartmentofWaterResources(DWR).Atthissametime,thedistrictpursuedloansthroughlocalbanks,whichprovidedachallengeconsideringtheunstablebankingindustry.Manycomponentsoftheprojectareproposedtobebuiltusinggrantfunding.FirstwasaChallengeGrantasprovidedbyUnitedStatesBureauofReclamation′s(USBR)Water2025program;providing9,000,000; a cost too high for the District to fund on their own. Because of the urgency of the project, The District explored multiple opportunities to fund the project. This included applying for loans, applying for grants, raising water rates, and raising land assessments; all at the same time. To obtain loan money the District applied for funds through Proposition 82, distributed by the Department of Water Resources (DWR). At this same time, the district pursued loans through local banks, which provided a challenge considering the unstable banking industry. Many components of the project are proposed to be built using grant funding. First was a Challenge Grant as provided by United States Bureau of Reclamation's (USBR) Water 2025 program; providing 300,000. Next was the USBR Field Services program; providing 25,000.Approximately25,000. Approximately 50,000 was utilized from the DWR Local Groundwater Assistance Program. In addition to these funds, Recovery Act funding became available for drought relief, where the District could obtain roughly $1,500,000. To generate further income the District approved a water rate increase. It was at this time when it became apparent that the Districts revenue source had become out of balance. The Land assessments were not enough to cover the operational overhead of the District. To rectify this issue, land assessments would need to be raised. This would require a proposition 218 election, which has been pursued. The intention of this paper is to discuss the multiple funding sources available to the District, how they were utilized, and problems that have been encountered

    USCID water management conference

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    Presented at Upgrading technology and infrastructure in a finance-challenged economy: a USCID water management conference held on March 23-26, 2010 in Sacramento, California.Includes bibliographical references.Water banks entail the recharge of periodically available excess surface water for storage underground and recovery when needed. Properly formulated, these projects are one of the most cost-effective water supply tools available. These projects are frequently located in rural areas due to availability of land and water. However, projects with capital programs of more than $10 million typically need to be funded with financing. Traditional financing mechanisms such as raising customer fees, bonding and state/federal grants are increasingly difficult to obtain. Therefore, many rural agencies pursue partnerships with urban water utilities that typically have more available capital. This approach, pioneered by Semitropic Water Storage District and Arvin-Edison Water Storage District in the 1990s, entails upfront payments (and annual operating fees) by the utilities in exchange for long-term leases of project capacity. The decision to use this funding approach must be made early in the project formulation because it requires that the project be sized and configured to meet both local and utility partner needs. Water utilities are only willing to enter into these partnerships if the project can increase their water supply reliability at a lower cost than other alternatives and only if three critical criteria have been met: 1) Lack of controversy as evidenced by tangible benefits to, oversight from and support by local stakeholders; 2) proven technical, regulatory and economic viability; and 3) operational flexibility and modularity, enabling construction in phases. A project should not be marketed before each element is in place. These requirements typically take several years and several million dollars to achieve

    USCID water management conference

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    Presented at Upgrading technology and infrastructure in a finance-challenged economy: a USCID water management conference held on March 23-26, 2010 in Sacramento, California.Includes bibliographical references.The Central Arizona Irrigation and Drainage District (CAIDD) began delivering water to users in 1989. Although designed for automatic control, the system was run manually until a homemade SCADA (Supervisory Control and Data Acquisition) system was developed by district employees. In 2002, problems with radio communication and limitations of the homemade SCADA system prompted CAIDD to begin the process of modernization. New spread-spectrum radios and RTUs (Remote Terminal Units) were purchased along with a commercial SCADA package (iFix by GE-IP). In 2005, CAIDD decided to pursue implementation of full automated control of a majority of district check gates. Currently, 125 gates are under remote manual supervisory control and 129 water levels are remotely monitored. CAIDD chose to implement SacMan (Software for Automated Canal Management) under development by the U.S. Arid Land Agricultural Research Center, Maricopa, AZ. The decision was made to only apply full automation at gates that had gate position sensors. Thus purchase and installation of gate position sensors have slowed implementation. To date, five lateral canals have been set up for full automatic control, where SacMan routes flow changes through the canal and uses downstream water level feedback control to correct for any errors that occur. The ditchrider only makes changes at the farm turnouts and district-operated wells. Automation of the Central Main canal has been tested in simulation. Control of this canal requires special treatment, as described in a companion paper. The district is waiting until enough of the canal is ready for automation before it turns automatic controls on 24/7, since this will require some operator training and remote oversight when problems occur. We hope this occurs in the summer of 2010
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