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Sample records for extended performance handheld

  1. EXTENDED PERFORMANCE HANDHELD AND MOBILE SENSORS FOR REMOTE DETECTION OF NATURAL GAS LEAKS

    SciTech Connect

    Michael B. Frish; B. David Green; Richard T. Wainner; Francesca Scire-Scappuzzo; Paul Cataldi; Matthew C. Laderer

    2005-05-01

    This report summarizes work performed by Physical Sciences Inc. (PSI) to advance the state-of-the-art of surveying for leaks of natural gas from transmission and distribution pipelines. The principal project goal was to develop means of deploying on an automotive platform an improved version of the handheld laser-based standoff natural gas leak detector previously developed by PSI and known as the Remote Methane Leak Detector or RMLD. A laser beam which interrogates the air for methane is projected from a spinning turret mounted upon a van. As the van travels forward, the laser beam scans an arc to the front and sides of the van so as to survey across streets and to building walls from a moving vehicle. When excess methane is detected within the arc, an alarm is activated. In this project, we built and tested a prototype Mobile RMLD (MRMLD) intended to provide lateral coverage of 10 m and one lateral scan for every meter of forward motion at forward speeds up to 10 m/s. Using advanced detection algorithms developed as part of this project, the early prototype MRMLD, installed on the back of a truck, readily detected simulated gas leaks of 50 liters per hour. As a supplement to the originally planned project, PSI also participated in a DoE demonstration of several gas leak detection systems at the Rocky Mountain Oilfield Testing Center (RMOTC) during September 2004. Using a handheld RMLD upgraded with the advanced detection algorithms developed in this project, from within a moving vehicle we readily detected leaks created along the 7.4 mile route of a virtual gas transmission pipeline.

  2. High performance hand-held gas chromatograph

    SciTech Connect

    Yu, C.M.

    1998-04-28

    The Microtechnology Center of Lawrence Livermore National Laboratory has developed a high performance hand-held, real time detection gas chromatograph (HHGC) by Micro-Electro-Mechanical-System (MEMS) technology. The total weight of this hand-held gas chromatograph is about five lbs., with a physical size of 8{close_quotes} x 5{close_quotes} x 3{close_quotes} including carrier gas and battery. It consumes about 12 watts of electrical power with a response time on the order of one to two minutes. This HHGC has an average effective theoretical plate of about 40k. Presently, its sensitivity is limited by its thermal sensitive detector at PPM. Like a conventional G.C., this HHGC consists mainly of three major components: (1) the sample injector, (2) the column, and (3) the detector with related electronics. The present HHGC injector is a modified version of the conventional injector. Its separation column is fabricated completely on silicon wafers by means of MEMS technology. This separation column has a circular cross section with a diameter of 100 pm. The detector developed for this hand-held GC is a thermal conductivity detector fabricated on a silicon nitride window by MEMS technology. A normal Wheatstone bridge is used. The signal is fed into a PC and displayed through LabView software.

  3. Turbulence degradation and mitigation performance for handheld weapon ID

    NASA Astrophysics Data System (ADS)

    Espinola, Richard L.; Aghera, Sameer; Thompson, Roger; Miller, Jason

    2012-06-01

    Atmospheric turbulence can severely limit the range performance of state-of-the-art large aperture imaging sensor systems, specifically those intended for long range ground to ground target identification. Simple and cost-effective mitigation solutions which operate in real-time are desired. Software-based post-processing techniques are attractive as they lend themselves to easy implementation and integration into the back-end of existing sensor systems. Recently, various post-processing algorithms to mitigate turbulence have been developed and implemented in real-time hardware. To determine their utility in Army-relevant tactical scenarios, an assessment of the impact of the post processing on observer performance is required. In this paper, we test a set of representative turbulence mitigation algorithms on field collected data of human targets carrying various handheld objects in varying turbulence conditions. We use a controlled human perception test to assess handheld weapon identification performance before and after turbulence mitigation post-processing. In addition, novel image analysis tools are implemented to estimate turbulence strength from the scene. Results of this assessment will lead to recommendations on cost-effective turbulence mitigation strategies suitable for future sensor systems.

  4. Performance of new handheld IR camera using uncooled bolometer FPA

    NASA Astrophysics Data System (ADS)

    Sone, Takanori; Ohkawa, Norio; Kawashima, Yasuo; Matsui, Yasuji; Sugiura, Yosuke; Araki, Tomiharu; Kamozawa, Makoto; Ueno, Masashi; Kaneda, Osamu; Ishikawa, Tomohiro; Hata, Hisatoshi; Hashima, Kazuo; Nakagi, Yoshiyuki; Yamada, Akira; Kimata, Masafumi

    1996-06-01

    A camera using an uncooled infrared image sensor has been developed. This image sensor is a bolometer focal plane array (FPA), of which the readout circuit is designed to minimize the temperature drift or the pattern noise caused by the changes of the ambient temperature. The circuit has a bolometer for the load resistor, which has the same temperature coefficient of resistance as that of the pixel bolometer. Therefore the signal change induced by the temperature change of the FPA substrate is reduced because the resistance change of the load bolometer compensates for that of the pixel bolometer. The effectiveness of the drift- compensating circuit has been confirmed with a prototype handheld camera.

  5. Performance of a 6-Degree-of-Freedom Active Microsurgical Manipulator in Handheld Tasks

    PubMed Central

    Yang, Sungwook; Wells, Trent S.; MacLachlan, Robert A.; Riviere, Cameron N.

    2013-01-01

    This paper presents the first experimental results from human users of a new 6-degree-of-freedom handheld micromanipulator. This is the latest prototype of a fully-handheld system, known as “Micron,” which performs active compensation of hand tremor for microsurgery. The manipulator is a miniature Gough-Stewart platform incorporating linear ultrasonic motors that provide a cylindrical workspace 4 mm long and 4 mm wide. In addition, the platform allows the possibility of imposing a remote center of motion for controlling motion not only at the tip but also at the entry point in the sclera of the eye. We demonstrate hand tremor reduction in both static and dynamic micromanipulation tasks on a rubber pad. The handheld performance is also evaluated in an artificial eye model while imposing a remote center of motion. In all cases, hand tremor is significantly reduced. PMID:24111024

  6. Performance assessments of Android-powered military applications operating on tactical handheld devices

    NASA Astrophysics Data System (ADS)

    Weiss, Brian A.; Fronczek, Lisa; Morse, Emile; Kootbally, Zeid; Schlenoff, Craig

    2013-05-01

    Transformative Apps (TransApps) is a Defense Advanced Research Projects Agency (DARPA) funded program whose goal is to develop a range of militarily-relevant software applications ("apps") to enhance the operational-effectiveness of military personnel on (and off) the battlefield. TransApps is also developing a military apps marketplace to facilitate rapid development and dissemination of applications to address user needs by connecting engaged communities of endusers with development groups. The National Institute of Standards and Technology's (NIST) role in the TransApps program is to design and implement evaluation procedures to assess the performance of: 1) the various software applications, 2) software-hardware interactions, and 3) the supporting online application marketplace. Specifically, NIST is responsible for evaluating 50+ tactically-relevant applications operating on numerous Android™-powered platforms. NIST efforts include functional regression testing and quantitative performance testing. This paper discusses the evaluation methodologies employed to assess the performance of three key program elements: 1) handheld-based applications and their integration with various hardware platforms, 2) client-based applications and 3) network technologies operating on both the handheld and client systems along with their integration into the application marketplace. Handheld-based applications are assessed using a combination of utility and usability-based checklists and quantitative performance tests. Client-based applications are assessed to replicate current overseas disconnected (i.e. no network connectivity between handhelds) operations and to assess connected operations envisioned for later use. Finally, networked applications are assessed on handhelds to establish baselines of performance for when connectivity will be common usage.

  7. User-friendly tools on handheld devices for observer performance study

    NASA Astrophysics Data System (ADS)

    Matsumoto, Takuya; Hara, Takeshi; Shiraishi, Junji; Fukuoka, Daisuke; Abe, Hiroyuki; Matsusako, Masaki; Yamada, Akira; Zhou, Xiangrong; Fujita, Hiroshi

    2012-02-01

    ROC studies require complex procedures to select cases from many data samples, and to set confidence levels in each selected case to generate ROC curves. In some observer performance studies, researchers have to develop software with specific graphical user interface (GUI) to obtain confidence levels from readers. Because ROC studies could be designed for various clinical situations, it is difficult task for preparing software corresponding to every ROC studies. In this work, we have developed software for recording confidence levels during observer studies on tiny personal handheld devices such as iPhone, iPod touch, and iPad. To confirm the functions of our software, three radiologists performed observer studies to detect lung nodules by using public database of chest radiograms published by Japan Society of Radiological Technology. The output in text format conformed to the format for the famous ROC kit from the University of Chicago. Times required for the reading each case was recorded very precisely.

  8. Technologist-performed handheld screening breast US imaging: how is it performed and what are the outcomes to date?

    PubMed

    Berg, Wendie A; Mendelson, Ellen B

    2014-07-01

    Breast density-inform legislation is increasing the need for data on outcomes of tailored screening. Dense parenchyma can mask cancers, and denser tissue is also more likely to develop breast cancer than fatty tissue. Digital mammography is standard for women with dense breasts. Supplemental screening magnetic resonance imaging should be offered to women who meet high-risk criteria. Supplemental screening ultrasonographic (US) imaging may be appropriate in the much larger group of women with dense breasts. Both physician- and technologist-performed screening US imaging increases detection of node-negative invasive breast cancer. To meet anticipated demand in the United States, screening US images will most likely be acquired by trained technologists rather than physicians. While automated US offers standard documentation, there are few data on outcomes. US has been used diagnostically for decades to characterize masses seen by using mammography, but training specific to screening has been lacking. Standard approaches to training and documentation of technologist-performed handheld screening US imaging are needed. This article reviews the current status of technologist-performed handheld screening breast US imaging. PMID:24956046

  9. Extended Techniques in Trumpet Performance and Pedagogy

    ERIC Educational Resources Information Center

    Cherry, Amy K.

    2009-01-01

    The impetus for this study was the question of whether extended techniques are actually being taught in college trumpet studio settings as standard skills necessary on the instrument. The specific purposes of this document included: (1) catalogue the extended techniques available to today's trumpet performer, (2) reflect on their current use and…

  10. Design, calibration, and performance of MICROTOPS II handheld ozone monitor and Sun photometer

    NASA Astrophysics Data System (ADS)

    Morys, Marian; Mims, Forrest M., III; Hagerup, Scott; Anderson, Stanley E.; Baker, Aaron; Kia, Jesse; Walkup, Travis

    2001-07-01

    MICROTOPS II is a five-channel, handheld Sun photometer that can be configured to measure total ozone, total water vapor, or aerosol optical thickness at various wavelengths. The instrument measures 10×20×4.3 cm and weighs 600 g. A principal design goal was the measurement of total ozone to within 1% of ozone measurements made by much larger, heavier, and more expensive Dobson and Brewer spectrophotometers. This goal has been met for a maximum air mass of up to ˜2.5, as demonstrated by comparisons of MICROTOPS II and its immediate predecessor, Supertops, with Dobson and Brewer instruments at various locations. Conventional interference filters are subject to gradual and unpredictable degradation. MICROTOPS II avoids these problems by using highly stable ultraviolet filters manufactured with an ion deposition process. The 2.4 nm (FWHM) band pass of the UV filters was selected to balance noise and ozone measurement performance. The optical collimators and electronics of the instrument were carefully designed to optimize pointing accuracy, stray light rejection, thermal and long-term stability, signal-to-noise ratio, and data analysis. An internal microcomputer automatically calculates the total ozone column based on measurements at three UV wavelengths, the site's geographic coordinates, and universal time, altitude, and pressure. The coordinates can be entered manually or by a Global Positioning System (GPS) receiver. A built-in pressure transducer automatically measures pressure. MICROTOPS II saves in nonvolatile memory up to 800 scans of the raw and calculated data. Measurements can be read from a liquid crystal display or transferred to an external computer.

  11. Extended-performance thruster technology evaluation

    NASA Technical Reports Server (NTRS)

    Beattie, J. R.; Poeschel, R. L.; Bechtel, R. T.

    1978-01-01

    Two 30-cm ion thruster technology areas are investigated in support of the extended-performance thruster operation required for the Halley's comet rendezvous mission. These areas include an evaluation of the thruster performance and lifetime characteristics at increased specific impulse and power levels, and the design and evaluation of a high-voltage propellant electrical isolator. Experimental results are presented indicating that all elements of the thruster design function well at the higher specific impulse and power levels. It is shown that the only thruster modifications required for extended-performance operation are a respacing of the ion optics assembly and a redesign of the propellant isolators. Experimental results obtained from three isolator designs are presented, and it is concluded that the design and development of a high-voltage isolator is possible using existing technology.

  12. Handheld Searchlight

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Streamlite Inc. reengineered the NASA searchlight for commercial use. The brightest hand-held light yet produced is result of Xenon-arc lights developed as solar simulators at Johnson Space Center. Intense battery powered searchlight is rated a million candlepower - 50 times brighter than high beam headlights of a car, and weighs only 7 pounds. Lifetime of xenon lamp is at least 200 hours at maximum intensity. Retail cost is under $400.00. Company has introduced smaller unit in shape of a flashlight, produces 20,000 candlepower and costs approximately $60.00.

  13. Design, construction and performance of a portable handheld electrohydrodynamic multi-needle spray gun for biomedical applications.

    PubMed

    Sofokleous, Panagiotis; Stride, Eleanor; Bonfield, William; Edirisinghe, Mohan

    2013-01-01

    Electrohydrodynamic (EHD) processing has attracted substantial interest in the technological and pharmaceutical sectors in recent years. Given the complexity of the process, exploring new ideas for EHD electrospraying and electrospinning delivery is a challenge. In this article, the design, construction and testing of a portable handheld EHD multi-needle device are described to produce multifunctional particles and fibers. Solid and encapsulated polymer particles and fibers were generated in order to study the performance of the device. The intrinsic properties of the feed solution/suspension and the processing conditions were adjusted to ensure robustness of the process and give uniform and reproducible products, with diameters ranging from the sub-micrometer scale to a few micrometers. These products have a broad range of applications in many advanced industrial sectors e.g. drug delivery systems, wound dressing patches, low calorie food products and cosmetics. PMID:25428065

  14. Extended Driving Impairs Nocturnal Driving Performances

    PubMed Central

    Sagaspe, Patricia; Taillard, Jacques; Åkerstedt, Torbjorn; Bayon, Virginie; Espié, Stéphane; Chaumet, Guillaume; Bioulac, Bernard; Philip, Pierre

    2008-01-01

    Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3–5am, 1–5am and 9pm–5am) on open highway. Fourteen young healthy men (mean age [±SD] = 23.4 [±1.7] years) participated Inappropriate line crossings (ILC) in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3–5am) driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05) for the intermediate (1–5am) driving session and by 4.0 (CI, 1.7 to 9.4; P<.001) for the long (9pm–5am) driving session. Compared to the reference session (9–10pm), the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001), 15.4 (CI, 4.6 to 51.5; P<.001) and 24.3 (CI, 7.4 to 79.5; P<.001), respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05) and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01). At night, extended driving impairs driving performances and therefore should be limited. PMID:18941525

  15. Assessment of the performance of a handheld Raman device for potential use as a screening tool in evaluating medicines quality.

    PubMed

    Hajjou, Mustapha; Qin, Yanyan; Bradby, Sanford; Bempong, Daniel; Lukulay, Patrick

    2013-02-23

    The TruScan(®) handheld Raman device is used for testing finished pharmaceutical products in the field to detect counterfeit and substandard medicines. Present work reports on the device's ability to discriminate between a specific product and similar products from different manufacturers, unrelated medicines, and medicines with different strengths. This investigation evaluated its ability to differentiate between similar drug products of similar or different strengths, focusing on the specificity and precision of the testing. First, several units of the same medicine's dosage form were compared; then comparisons were made between unrelated products, similar products, and products with different strengths. The six pharmaceutical products used in testing were from commonly used analgesic, antimalarial, and antidiarrheal medicines. The results showed that the performance of the TruScan(®) device depends on the nature and the strength of the dosage form tested; while the device could be suitable for authentication of some finished pharmaceutical products and, hence, could be used to detect some counterfeit medicines, it could not be used to detect substandard medicines. Careful consideration should be given when using the device as a screening tool for counterfeit medicines. PMID:23245232

  16. Handheld computing in pathology

    PubMed Central

    Park, Seung; Parwani, Anil; Satyanarayanan, Mahadev; Pantanowitz, Liron

    2012-01-01

    Handheld computing has had many applications in medicine, but relatively few in pathology. Most reported uses of handhelds in pathology have been limited to experimental endeavors in telemedicine or education. With recent advances in handheld hardware and software, along with concurrent advances in whole-slide imaging (WSI), new opportunities and challenges have presented themselves. This review addresses the current state of handheld hardware and software, provides a history of handheld devices in medicine focusing on pathology, and presents future use cases for such handhelds in pathology. PMID:22616027

  17. A Foothold for Handhelds.

    ERIC Educational Resources Information Center

    Joyner, Amy

    2003-01-01

    Handheld computers provide students tremendous computing and learning power at about a 10th the cost of a regular computer. Describes the evolution of handhelds; provides some examples of their uses; and cites research indicating they are effective classroom tools that can improve efficiency and instruction. A sidebar lists handheld resources.…

  18. A Scaffolding Strategy to Develop Handheld Sensor-Based Vocabulary Games for Improving Students' Learning Motivation and Performance

    ERIC Educational Resources Information Center

    Huang, Yong-Ming; Huang, Yueh-Min

    2015-01-01

    Vocabulary is the foundation for students who learn a foreign language. Nevertheless, students may be bored by the painstaking process of rote learning. To this end, this study designed a handheld sensor-based vocabulary game based on a scaffolding strategy for improving students' motivation and achievement in vocabulary learning. On the one hand,…

  19. Performance, Accuracy, Data Delivery, and Feedback Methods in Order Selection: A Comparison of Voice, Handheld, and Paper Technologies

    ERIC Educational Resources Information Center

    Ludwig, Timothy D.; Goomas, David T.

    2007-01-01

    Field study was conducted in auto-parts after-market distribution centers where selectors used handheld computers to receive instructions and feedback about their product selection process. A wireless voice-interaction technology was then implemented in a multiple baseline fashion across three departments of a warehouse (N = 14) and was associated…

  20. Handheld Universal Diagnostic Sensor

    NASA Technical Reports Server (NTRS)

    Chan, Eugene

    2012-01-01

    The rHEALTH technology is designed to shrink an entire hospital testing laboratory onto a handheld device. A physician or healthcare provider performs the test by collecting a fingerstick of blood from a patient. The tiny volume of blood is inserted into the rHEALTH device. Inside the device is a microfluidic chip that contains small channels about the width of a human hair. These channels help move the blood and analyze the blood sample. The rHEALTH sensor uses proprietary reagents called nanostrips, which are nanoscale test strips that enable the clinical assays. The readout is performed by laser-induced fluorescence. Overall, the time from blood collection through analysis is less than a minute.

  1. Performance of a Multispectral Optoacoustic Tomography (MSOT) System equipped with 2D vs. 3D Handheld Probes for Potential Clinical Translation

    PubMed Central

    Neuschmelting, Volker; Burton, Neal C.; Lockau, Hannah; Urich, Alexander; Harmsen, Stefan; Ntziachristos, Vasilis; Kircher, Moritz F.

    2015-01-01

    A handheld approach to optoacoustic imaging is essential for the clinical translation. The first 2- and 3-dimensional handheld multispectral optoacoustic tomography (MSOT) probes featuring real-time unmixing have recently been developed. Imaging performance of both probes was determined in vitro and in a brain melanoma metastasis mouse model in vivo. T1-weighted MR images were acquired for anatomical reference. The limit of detection of melanoma cells in vitro was significantly lower using the 2D than the 3D probe. The signal decrease was more profound in relation to depth with the 3D versus the 2D probe. Both approaches were capable of imaging the melanoma tumors qualitatively at all time points. Quantitatively, the 2D approach enabled closer anatomical resemblance of the tumor compared to the 3D probe, particularly at depths beyond 3 mm. The 3D probe was shown to be superior for rapid 3D imaging and, thus, holds promise for more superficial target structures. PMID:27069872

  2. Performance map of a cluster detection test using extended power

    PubMed Central

    2013-01-01

    Background Conventional power studies possess limited ability to assess the performance of cluster detection tests. In particular, they cannot evaluate the accuracy of the cluster location, which is essential in such assessments. Furthermore, they usually estimate power for one or a few particular alternative hypotheses and thus cannot assess performance over an entire region. Takahashi and Tango developed the concept of extended power that indicates both the rate of null hypothesis rejection and the accuracy of the cluster location. We propose a systematic assessment method, using here extended power, to produce a map showing the performance of cluster detection tests over an entire region. Methods To explore the behavior of a cluster detection test on identical cluster types at any possible location, we successively applied four different spatial and epidemiological parameters. These parameters determined four cluster collections, each covering the entire study region. We simulated 1,000 datasets for each cluster and analyzed them with Kulldorff’s spatial scan statistic. From the area under the extended power curve, we constructed a map for each parameter set showing the performance of the test across the entire region. Results Consistent with previous studies, the performance of the spatial scan statistic increased with the baseline incidence of disease, the size of the at-risk population and the strength of the cluster (i.e., the relative risk). Performance was heterogeneous, however, even for very similar clusters (i.e., similar with respect to the aforementioned factors), suggesting the influence of other factors. Conclusions The area under the extended power curve is a single measure of performance and, although needing further exploration, it is suitable to conduct a systematic spatial evaluation of performance. The performance map we propose enables epidemiologists to assess cluster detection tests across an entire study region. PMID:24156765

  3. Development of a Minimum Performance Standard for Hand-Held Fire Extinguishers as a Replacement for Halon 1211 on Civilian Transport Category Aircraft

    NASA Astrophysics Data System (ADS)

    Webster, Harry

    2002-08-01

    One or more Halon 1211 hand-held fire extinguishers are specified in Federal Aviation Regulation (FAR) Part 25.851 as a requirement on transport category aircraft with 31 or more seats. Halon 1211 has been linked to the destruction of the ozone layer and production of new Halon 1211 has been halted per the Montreal Protocol in 1993. The phase out of Halon 1211, as the hand-held firefighting agent of choice, for civilian transport category aircraft has necessitated the development of a Minimum Performance Standard (MPS) to evaluate replacement agents. The purpose of the MPS is to insure that there is no reduction in safety, both in terms of effectiveness in fighting onboard fires and toxicity to the passengers and crew. The MPS specifies two new tests that replacement agents must pass in addition to requiring national certifications such as provided by Underwriters Laboratories. The first test evaluates the "flooding" characteristics of the agent against a hidden in-flight fire. This test determines the ability of a streaming agent to function as a flooding agent. The second test evaluates the performance of the agent in fighting a terrorist fire scenario and the associated toxicity hazard. This test measures the agent's ability to extinguish a triple-seat fire in an aircraft cabin under in-flight conditions and the toxicity characteristics of both the neat agent and the products of decomposition. This MPS will insure that the replacement agents will meet or exceed the performance of Halon 1211 both in fighting fires and maintaining a safe breathing environment in aircraft cabins.

  4. Handheld Computing in Medicine

    PubMed Central

    Fischer, Sandra; Stewart, Thomas E.; Mehta, Sangeeta; Wax, Randy; Lapinsky, Stephen E.

    2003-01-01

    Handheld computers have become a valuable and popular tool in various fields of medicine. A systematic review of articles was undertaken to summarize the current literature regarding the use of handheld devices in medicine. A variety of articles were identified, and relevant information for various medical fields was summarized. The literature search covered general information about handheld devices, the use of these devices to access medical literature, electronic pharmacopoeias, patient tracking, medical education, research, business management, e-prescribing, patient confidentiality, and costs as well as specialty-specific uses for personal digital assistants (PDAs). The authors concluded that only a small number of articles provide evidence-based information about the use of PDAs in medicine. The majority of articles provide descriptive information, which is nevertheless of value. This article aims to increase the awareness among physicians about the potential roles for handheld computers in medicine and to encourage the further evaluation of their use. PMID:12595403

  5. Handheld computing in medicine.

    PubMed

    Fischer, Sandra; Stewart, Thomas E; Mehta, Sangeeta; Wax, Randy; Lapinsky, Stephen E

    2003-01-01

    Handheld computers have become a valuable and popular tool in various fields of medicine. A systematic review of articles was undertaken to summarize the current literature regarding the use of handheld devices in medicine. A variety of articles were identified, and relevant information for various medical fields was summarized. The literature search covered general information about handheld devices, the use of these devices to access medical literature, electronic pharmacopoeias, patient tracking, medical education, research, business management, e-prescribing, patient confidentiality, and costs as well as specialty-specific uses for personal digital assistants (PDAs). The authors concluded that only a small number of articles provide evidence-based information about the use of PDAs in medicine. The majority of articles provide descriptive information, which is nevertheless of value. This article aims to increase the awareness among physicians about the potential roles for handheld computers in medicine and to encourage the further evaluation of their use. PMID:12595403

  6. Toward Extending the Educational Interpreter Performance Assessment to Cued Speech

    ERIC Educational Resources Information Center

    Krause, Jean C.; Kegl, Judy A.; Schick, Brenda

    2008-01-01

    The Educational Interpreter Performance Assessment (EIPA) is as an important research tool for examining the quality of interpreters who use American Sign Language or a sign system in classroom settings, but it is not currently applicable to educational interpreters who use Cued Speech (CS). In order to determine the feasibility of extending the…

  7. Handheld ultrasound array imaging device

    NASA Astrophysics Data System (ADS)

    Hwang, Juin-Jet; Quistgaard, Jens

    1999-06-01

    A handheld ultrasound imaging device, one that weighs less than five pounds, has been developed for diagnosing trauma in the combat battlefield as well as a variety of commercial mobile diagnostic applications. This handheld device consists of four component ASICs, each is designed using the state of the art microelectronics technologies. These ASICs are integrated with a convex array transducer to allow high quality imaging of soft tissues and blood flow in real time. The device is designed to be battery driven or ac powered with built-in image storage and cineloop playback capability. Design methodologies of a handheld device are fundamentally different to those of a cart-based system. As system architecture, signal and image processing algorithm as well as image control circuit and software in this device is deigned suitably for large-scale integration, the image performance of this device is designed to be adequate to the intent applications. To elongate the battery life, low power design rules and power management circuits are incorporated in the design of each component ASIC. The performance of the prototype device is currently being evaluated for various applications such as a primary image screening tool, fetal imaging in Obstetrics, foreign object detection and wound assessment for emergency care, etc.

  8. Pyxis handheld polarimetric imager

    NASA Astrophysics Data System (ADS)

    Chenault, David B.; Pezzaniti, J. Larry; Vaden, Justin P.

    2016-05-01

    The instrumentation for measuring infrared polarization signatures has seen significant advancement over the last decade. Previous work has shown the value of polarimetric imagery for a variety of target detection scenarios including detection of manmade targets in clutter and detection of ground and maritime targets while recent work has shown improvements in contrast for aircraft detection and biometric markers. These data collection activities have generally used laboratory or prototype systems with limitations on the allowable amount of target motion or the sensor platform and usually require an attached computer for data acquisition and processing. Still, performance and sensitivity have been steadily getting better while size, weight, and power requirements have been getting smaller enabling polarimetric imaging for a greater or real world applications. In this paper, we describe Pyxis®, a microbolometer based imaging polarimeter that produces live polarimetric video of conventional, polarimetric, and fused image products. A polarization microgrid array integrated in the optical system captures all polarization states simultaneously and makes the system immune to motion artifacts of either the sensor or the scene. The system is battery operated, rugged, and weighs about a quarter pound, and can be helmet mounted or handheld. On board processing of polarization and fused image products enable the operator to see polarimetric signatures in real time. Both analog and digital outputs are possible with sensor control available through a tablet interface. A top level description of Pyxis® is given followed by performance characteristics and representative data.

  9. Social identity performance: extending the strategic side of SIDE.

    PubMed

    Klein, Olivier; Spears, Russell; Reicher, Stephen

    2007-02-01

    This article extends the social identity model of deindividuation effects (SIDE) by considering the various ways in which relations of visibility to an audience can affect the public expression of identity-relevant norms (identity performance). It is suggested that social identity performance can fulfill two general functions: Affirming, conforming, or strengthening individual or group identities (the identity consolidation function) and persuading audiences into adopting specific behaviors (the mobilization function). The authors report evidence supporting these two functions of identity performance both in intragroup and intergroup contexts. They argue that through these functions, social identity performance plays a major role in the elaboration and coordination of social action. Finally, and building on this framework, the authors consider the ways through which social identity performance can be used in the very construction of social identity. PMID:18453454

  10. Extended temperature performance of 120 Gbps midboard optical engine

    NASA Astrophysics Data System (ADS)

    Cornelius, Joshua R.; Baumer, Aaron M.; Zbinden, Eric J.; Langsam, David P.; Verdiell, Jean-Marc A.; Kozlovsky, William J.; Hazell, John F.; Eichhorn, Catherine M.; Lutz, Sharon M.; Mitcheltree, Thomas J.

    2016-03-01

    Industrial and military requirements for optics dictate the ability to operate reliably over a myriad of extreme environmental conditions such as extended temperature, increased shock and vibration, high particulate environments, etc. While it is paramount that the transceiver be able to maintain performance over these extreme conditions, considerations for the optical interconnects in the signal path are often overlooked. In general, optical performance tends to degrade as the operating temperature drifts from nominal conditions. Likewise, optical connector performance degrades at higher shock and vibration levels. As a result, optical products are generally limited to operating at case temperatures between 0 °C - 70 °C and struggle at high shock and vibration levels. In this paper we demonstrate the performance of the Samtec 12 channel FireFlyTM at 10 Gbps, -40 °C and 85 °C case temperature coupled with the expanded beam MXCTM connector from US Conec. Optical eye diagrams and receiver sensitivity for a link that includes 100 m of OM3 fiber, reliability results for transmitters operating at extended temperature, and shock and vibration data are presented.

  11. Miniaturized handheld hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Wu, Huawen; Haibach, Frederick G.; Bergles, Eric; Qian, Jack; Zhang, Charlie; Yang, William

    2014-05-01

    A miniaturized hyperspectral imager is enabled with image sensor integrated with dispersing elements in a very compact form factor, removing the need for expensive, moving, bulky and complex optics that have been used in conventional hyperspectral imagers for decades. The result is a handheld spectral imager that can be installed on miniature UAV drones or conveyor belts in production lines. Eventually, small handhelds can be adapted for use in outpatient medical clinics for point-of-care diagnostics and other in-field applications.

  12. Resistor array performance errors associated with extended targets

    NASA Astrophysics Data System (ADS)

    Sisko, R. Bryan; Marlow, Steven A.; Huber, August J.; Thompson, Rhoe A.

    2006-05-01

    In recent hardware-in-the-loop tests conducted in a cryogenic chamber, a dual band sensor observed radiometric anomalies for extended targets. In order to understand the radiometric errors associated with the infrared projection arrays, systematic measurements were performed at both cryogenic and ambient temperatures. Air Force Research Laboratory (AFRL) engineers have previously investigated an artifact observed in these arrays called "busbar robbing," but these observations were of square blocks of emitters and did not characterize radiometric accuracy of extended targets in a dynamic engagement scenario. It was discovered that when numerous emitters in a contiguous pattern are turned on, rather than scattered over the array, the "busbar robbing" effect causes the actual emitter outputs to be different from what you measure if you drive them to the same level with fewer pixels. When the emitters that are driven have some "aspect ratio" or elongated shape, then the effect is dependent on how this pattern is aligned with the emitter axes. The results of these experiments address the radiometric error that can be expected from the resistor array projectors for end game scenarios when a target becomes extended at both ambient and cryogenic temperatures.

  13. Medical, Psychophysiological, and Human Performance Problems During Extended EVA

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In this session, Session JP1, the discussion focuses on the following topics: New Developments in the Assessment of the Risk of Decompression Sickness in Null Gravity During Extravehicular Activity; The Dynamic of Physiological Reactions of Cosmonauts Under the Influence of Repeated EVA Workouts, The Russian Experience; Medical Emergencies in Space; The Evolution from 'Physiological Adequacy' to 'Physiological Tuning'; Five Zones of Symmetrical and Asymmetrical Conflicting Temperatures on the Human Body, Physiological Consequences; Human Performance and Subjective Perception in Nonuniform Thermal Conditions; The Hand as a Control System, Implications for Hand-Finger Dexterity During Extended EVA; and Understanding the Skill of Extravehicular Mass Handling.

  14. Handhelds, Testing and Teaching

    ERIC Educational Resources Information Center

    Technology & Learning, 2005

    2005-01-01

    Research shows that technology makes a difference in student motivation, engagement, and active learning. It also helps students develop critical thinking, collaboration, and problem-solving skills. Providing each student with his or her own computing device such as a Palm handheld computer and appropriate software can have a great impact. This…

  15. Vibration absorber modeling for handheld machine tool

    NASA Astrophysics Data System (ADS)

    Abdullah, Mohd Azman; Mustafa, Mohd Muhyiddin; Jamil, Jazli Firdaus; Salim, Mohd Azli; Ramli, Faiz Redza

    2015-05-01

    Handheld machine tools produce continuous vibration to the users during operation. This vibration causes harmful effects to the health of users for repeated operations in a long period of time. In this paper, a dynamic vibration absorber (DVA) is designed and modeled to reduce the vibration generated by the handheld machine tool. Several designs and models of vibration absorbers with various stiffness properties are simulated, tested and optimized in order to diminish the vibration. Ordinary differential equation is used to derive and formulate the vibration phenomena in the machine tool with and without the DVA. The final transfer function of the DVA is later analyzed using commercial available mathematical software. The DVA with optimum properties of mass and stiffness is developed and applied on the actual handheld machine tool. The performance of the DVA is experimentally tested and validated by the final result of vibration reduction.

  16. Extending the boundaries of family medicine to perform manual procedures.

    PubMed

    Bitterman, Haim; Vinker, Shlomo

    2014-01-01

    A recent survey by Menahem and colleagues revealed that 65% of the surveyed primary care physicians reported that they performed any minor surgical procedures, and 46% reported performance of any musculoskeletal injections. Lack of allocated time and lack of training were the main reported barriers confronting higher performance rates. Healthcare systems are shifting large chunks of traditional hospital-centered activities to competent and comprehensive community-based structures. These changes are very well aligned with key trends in modern consumerism that prefer a close to home availability of medical services. Minor surgical procedures and musculoskeletal injections are good examples of medical activities that had been performed mainly by hospital and community based specialists. The syllabus of specialty training in Family Medicine in Israel includes these skills and trainees should acquire them during the residency program. We estimate that hundreds of family physicians obtain different levels of such training. Yet, only few family physicians have allocated protected time for performance of the procedures. For the skilled physician, performance of such relatively simple procedures extends his professional boundaries and the comprehensiveness of his service. For the healthcare system the "extra effort" and investment needed for performance of minor surgical procedures in primary care clinics is small. The results of the present study reflect on wider issues of care delivery. This study highlights the need for formalized and documented training of family physicians together with allocation of managerial and technical requirements needed to encourage these and similar medically and economically justified endeavors that seem to be perfectly aligned with the wishes of healthcare consumers. PMID:25383180

  17. Extended performance solar electric propulsion thrust system design

    NASA Technical Reports Server (NTRS)

    Cake, J. E.; Hawthorne, E. I.; Poeschel, R. L.

    1978-01-01

    A thrust system design has been established for an extended performance technology, 6.4 kW, 4800 sec specific impulse ion thruster. The configuration is comprised of ten thrusters configured with a power management and control subsystem in a modular thrust system design. The system design approach is an adaptation of that previously established for the baseline technology 2.7 kW, 3000 sec specific impulse ion thruster. The power management and control subsystem design includes a combination of individual electronics for each thruster and a set of electronics with redundancy that are common to all thrusters. The thermal dissipation from all electronics is removed with a common heat pipe/radiator assembly.

  18. Handheld real-time PCR device.

    PubMed

    Ahrberg, Christian D; Ilic, Bojan Robert; Manz, Andreas; Neužil, Pavel

    2016-02-01

    Here we report one of the smallest real-time polymerase chain reaction (PCR) systems to date with an approximate size of 100 mm × 60 mm × 33 mm. The system is an autonomous unit requiring an external 12 V power supply. Four simultaneous reactions are performed in the form of virtual reaction chambers (VRCs) where a ≈200 nL sample is covered with mineral oil and placed on a glass cover slip. Fast, 40 cycle amplification of an amplicon from the H7N9 gene was used to demonstrate the PCR performance. The standard curve slope was -3.02 ± 0.16 cycles at threshold per decade (mean ± standard deviation) corresponding to an amplification efficiency of 0.91 ± 0.05 per cycle (mean ± standard deviation). The PCR device was capable of detecting a single deoxyribonucleic acid (DNA) copy. These results further suggest that our handheld PCR device may have broad, technologically-relevant applications extending to rapid detection of infectious diseases in small clinics. PMID:26753557

  19. VALIDATION OF ANSI N42.34 AMERICAN NATIONAL STANDARD PERFORMANCE CRITERIA FOR HAND-HELD INSTRUMENTS FOR THE DETECTION AND IDENTIFICATION OF RADIONUCLIDES

    SciTech Connect

    Lorier, T.

    2014-09-03

    SRNL’s validation of ANSI N42.34-D6 for the Domestic Nuclear Detection Office (DNDO) was performed utilizing one hand-held instrument (or RID) – the FLIR identiFINDER 2. Each section of the standard was evaluated via a walk-through or test. NOTE: In Table 1, W = walk-through and T = test, as directed by the Domestic Nuclear Detection Office (DNDO). For a walk-through, the experiment was either setup or reviewed for setup; for a test, the N42.34-D6 procedures were followed with some exceptions and comments noted. SRNL is not fully able to evaluate a RID against Sections 7 (Environmental), 8 (Electromagnetic), and 9 (Mechanical) of N42.34, so those portions of this validation were done in collaboration with Qualtest, Inc. in Orlando, Florida. The walk-throughs and tests of Sections 7, 8, and 9 were performed in Qualtest, Inc. facilities with SRNL providing radiological sources as necessary. Where applicable, assessment results and findings of the walk-throughs and tests were recorded on datasheets and a validation summary is provided. A general comment pertained to test requirements found in another standard and referenced in N42.34-D6. For example, step 1 of the test method in section 8.1.2 states “RF test set up information can be found in IEC 61000-4-3.” It is recommended that any information from other standards necessary for conducting the tests within N42.34 should be posted in N42.34 for simplicity and to prevent the user from having to peruse other documents. Another general comment, as noted by Qualtest, is that a tolerance reference is not listed for each test in sections 7-9. Overall, the N42.34-D6 was proven to be practicable, but areas for improvement and recommendations were identified for consideration prior to final ballot submittal.

  20. An Accelerometer-Based Handheld System to Reduce Breaks in Performance of Young Adults with Cognitive Impairments

    ERIC Educational Resources Information Center

    Chang, Yao-Jen; Chen, Shu-Fang; Lu, Zhi-Zhan

    2011-01-01

    This study assessed the possibility of training two individuals with cognitive impairments using a system that reduced breaks in performance. This study was carried out according to an ABAB sequence in which A represented the baseline and B represented intervention phases. Data showed that the two participants significantly increased their target…

  1. Cell Micromanipulation with an Active Handheld Micromanipulator

    PubMed Central

    Tabarés, Jaime Cuevas; MacLachlan, Robert A.; Ettensohn, Charles A.

    2012-01-01

    The paper describes the use of an active handheld micromanipulator, known as Micron, for micromanipulation of cells. The device enables users to manipulate objects on the order of tens of microns in size, with the natural ease of use of a fully handheld tool. Micron senses its own position using a purpose-built microscale optical tracker, estimates the erroneous or undesired component of hand motion, and actively corrects it by deflecting its own tool tip using piezoelectric actuators. Benchtop experiments in tip positioning show that active compensation can reduce positioning error by up to 51% compared to unaided performance. Preliminary experiments in bisection of sea urchin embryos exhibit an increased success rate when performed with the help of Micron. PMID:21096452

  2. Handheld CZT radiation detector

    SciTech Connect

    Murray, William S.; Butterfield, Kenneth B.; Baird, William

    2004-08-24

    A handheld CZT radiation detector having a CZT gamma-ray sensor, a multichannel analyzer, a fuzzy-logic component, and a display component is disclosed. The CZT gamma-ray sensor may be a coplanar grid CZT gamma-ray sensor, which provides high-quality gamma-ray analysis at a wide range of operating temperatures. The multichannel analyzer categorizes pulses produce by the CZT gamma-ray sensor into channels (discrete energy levels), resulting in pulse height data. The fuzzy-logic component analyzes the pulse height data and produces a ranked listing of radioisotopes. The fuzzy-logic component is flexible and well-suited to in-field analysis of radioisotopes. The display component may be a personal data assistant, which provides a user-friendly method of interacting with the detector. In addition, the radiation detector may be equipped with a neutron sensor to provide an enhanced mechanism of sensing radioactive materials.

  3. Handheld THz security imaging

    NASA Astrophysics Data System (ADS)

    Duling, Irl N.

    2016-05-01

    Terahertz energy, with its ability to penetrate clothing and non-conductive materials, has held much promise in the area of security scanning. Millimeter wave systems (300 GHz and below) have been widely deployed. These systems have used full two-dimensional surface imaging, and have resulted in privacy concerns. Pulsed terahertz imaging, can detect the presence of unwanted objects without the need for two-dimensional photographic imaging. With high-speed waveform acquisition it is possible to create handheld tools that can be used to locate anomalies under clothing or headgear looking exclusively at either single point waveforms or cross-sectional images which do not pose a privacy concern. Identification of the anomaly to classify it as a potential threat or a benign object is also possible.

  4. Handheld ultrasonic concealed weapon detector

    NASA Astrophysics Data System (ADS)

    Wild, Norbert C.; Doft, Frank; Breuner, Dennis; Felber, Franklin S.

    2001-02-01

    A handheld, battery-operated prototype of a concealed weapon detector has been built and tested. Designed to detect both metallic and non-metallic weapons, the sensor utilizes focused ultrasound (40 kHz frequency) to remotely detect concealed objects from beyond arm's length out to a range of about 12 feet (4 meters). The detector can be used in prison settings, by officers in the field to allow for stand-off frisking of suspects, and to supplement security at courthouse entrances and other monitored portals. The detector emits an audible alarm (with provision for an earphone jack) as well as a visible light-bar indicator when an object is detected. A high intensity aiming light, with momentary switch, allows the user to accurately determine the location of the concealed object. Current efforts are aimed at increasing the probability of detection, reducing the false-alarm rate, and extending the range of detectability out to 20 feet. Plans for accomplishing these tasks will be presented together with data showing the effective range and probability of detection for the present system.

  5. Normal neurocognitive performance after extended practice in patients with schizophrenia.

    PubMed

    Wexler, B E; Hawkins, K A; Rounsaville, B; Anderson, M; Sernyak, M J; Green, M F

    1997-08-29

    This study evaluated new methods for improving the performance of patients with schizophrenia on specific neurocognitive tasks. Patients (n = 22) practiced sustained perceptual, memory and motor tasks 5 times/week for 10 weeks. Tasks were initially easy enough for patients to do well, but were made gradually more difficult over the 10 weeks. Patients received base pay and performance-based monetary supplements. No coaching or ongoing instruction was provided, and performance gains were assumed to depend upon implicit learning. High functioning healthy controls (n = 5) were given the same tasks at difficulty levels comparable to those achieved by patients after 10 weeks of practice. After 10 weeks of practice, 16 of the 22 patients performed as well or better than the best control on the perceptual and memory tasks, and 11 patients performed within the range of control subjects on the motor task. Half of the patients retested 6 months after training maintained supranormal performance, while the others showed marked performance declines. Patients with schizophrenia appear to have greater potential for neurocognitive improvement, and potentially for employment, than generally appreciated. PMID:9323348

  6. Extending Our Understanding of Compliant Thermal Barrier Performance

    NASA Technical Reports Server (NTRS)

    Demange, Jeffrey J.; Finkbeiner, Joshua R.; Dunlap, Patrick H.

    2014-01-01

    Thermal barriers and seals are integral components in the thermal protection systems (TPS) of nearly all aerospace vehicles. They are used to minimize the flow of hot gases through interfaces and protect underlying temperature-sensitive components and systems. Although thermal barriers have been used extensively on many aerospace vehicles, the factors affecting their thermal and mechanical performance are not well-understood. Because of this, vehicle TPS designers are often left with little guidance on how to properly design and optimize these barriers. An ongoing effort to better understand thermal barrier performance and develop models and design tools is in progress at the NASA Glenn Research Center. Testing has been conducted to understand the degree to which insulation density influences structural performance and permeability. In addition, the development of both thermal and mechanical models is ongoing with the goal of providing an improved ability to design and implement these critical TPS components.

  7. Handheld Diffusion Test Cells

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This photo shows an individual cell from the Handheld Diffusion Test Cell (HH-DTC) apparatus flown on the Space Shuttle. Similar cells will be used in the Observable Protein Crystal Growth Apparatus (OPCGA) to be operated aboard the International Space Station (ISS). The principal investigator is Dr. Alex McPherson of the University of California, Irvine. Each individual cell comprises two sample chambers with a rotating center section that isolates the two from each other until the start of the experiment and after it is completed. The cells are made from optical-quality quartz glass to allow photography and interferometric observations. Each cell has a small light-emitting diode and lens to back-light the solution. In protein crystal growth experiments, a precipitating agent such as a salt solution is used to absorb and hold water but repel the protein molecules. This increases the concentration of protein until the molecules nucleate to form crystals. This cell is one of 96 that make up the experiment module portion of the OPCGA.

  8. Handheld Diffusion Test Cells

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This photo shows the Handheld Diffusion Test Cell (HH-DTC) apparatus flown on the Space Shuttle. Similar cells (inside the plastic box) will be used in the Observable Protein Crystal Growth Apparatus (OPCGA) to be operated aboard the International Space Station (ISS). The principal investigator is Dr. Alex McPherson of the University of California, Irvine. Each individual cell comprises two sample chambers with a rotating center section that isolates the two from each other until the start of the experiment and after it is completed. The cells are made from optical-quality quartz glass to allow photography and interferometric observations. Each cell has a small light-emitting diode and lens to back-light the solution. In protein crystal growth experiments, a precipitating agent such as a salt solution is used to absorb and hold water but repel the protein molecules. This increases the concentration of protein until the molecules nucleate to form crystals. This cell is one of 96 that make up the experiment module portion of the OPCGA.

  9. Handheld hyperspectral imager

    NASA Astrophysics Data System (ADS)

    Saari, Heikki; Aallos, Ville-Veikko; Holmlund, Christer; Malinen, Jouko; Mäkynen, Jussi

    2010-04-01

    VTT Technical Research Centre of Finland has developed a new low cost hand-held staring hyperspectral imager for applications previously blocked by high cost of the instrumentation. The system is compatible with standard video and microscope lenses. The instrument can record 2D spatial images at several wavelength bands simultaneously. The concept of the hyperspectral imager has been published in SPIE Proc. 7474. The prototype fits in an envelope of 100 mm x 60 mm x 40 mm and its weight is ca. 300 g. The benefits of the new device compared to Acousto-Optic Tunable filter (AOTF) or Liquid Crystal Tunable Filter (LCTF) devices are small size and weight, speed of wavelength tuning, high optical throughput, independence of polarization state of incoming light and capability to record three wavelengths simultaneously. The operational wavelength range with Silicon-based CCD or CMOS sensors is 200 - 1100 nm and spectral resolution is 2 - 10 nm @ FWHM. Similar IR imagers can be built using InGaAs, InSb or MCT imaging sensors. The spatial resolution of the prototype is 480 x 750 pixels. It contains control system and memory for the image data acquisition. It operates either autonomously recording hyperspectral data cubes continuously or controlled by a laptop computer. The prototype was configured as a hyperspectral microscope for the spectral range 400 - 700 nm. The design of the hyperspectral imager, characterization results and sample measurement results are presented.

  10. Seed vigour and crop establishment: extending performance beyond adaptation.

    PubMed

    Finch-Savage, W E; Bassel, G W

    2016-02-01

    Seeds are central to crop production, human nutrition, and food security. A key component of the performance of crop seeds is the complex trait of seed vigour. Crop yield and resource use efficiency depend on successful plant establishment in the field, and it is the vigour of seeds that defines their ability to germinate and establish seedlings rapidly, uniformly, and robustly across diverse environmental conditions. Improving vigour to enhance the critical and yield-defining stage of crop establishment remains a primary objective of the agricultural industry and the seed/breeding companies that support it. Our knowledge of the regulation of seed germination has developed greatly in recent times, yet understanding of the basis of variation in vigour and therefore seed performance during the establishment of crops remains limited. Here we consider seed vigour at an ecophysiological, molecular, and biomechanical level. We discuss how some seed characteristics that serve as adaptive responses to the natural environment are not suitable for agriculture. Past domestication has provided incremental improvements, but further actively directed change is required to produce seeds with the characteristics required both now and in the future. We discuss ways in which basic plant science could be applied to enhance seed performance in crop production. PMID:26585226

  11. At Ease in the Handheld World.

    ERIC Educational Resources Information Center

    Levinson, Eliot; Grohe, Barbara

    2001-01-01

    Provides educational decision-makers with an overview of the offerings and issues related to adopting handheld computers. Describes several handheld products available to schools, including: Palm, iPAQ, Mindsurf, Symbol Technologies, Texas Instruments, and Gateway Handspring Visor. Compares handhelds to PCs, in terms of functionality, operating…

  12. Extended Time Accommodations and the Mathematics Performance of Students with and without ADHD

    ERIC Educational Resources Information Center

    Lewandowski, Lawrence J.; Lovett, Benjamin J.; Parolin, Rosanne; Gordon, Michael; Codding, Robin S.

    2007-01-01

    Test accommodations such as extended time are presumed to reduce the impact of a disability, while not affecting test scores of the general population. This study examined the effects of an extended time (time and one-half) accommodation on the mathematics performance of fifth- to seventh-grade students with and without attention deficit…

  13. Hand-held medical robots.

    PubMed

    Payne, Christopher J; Yang, Guang-Zhong

    2014-08-01

    Medical robots have evolved from autonomous systems to tele-operated platforms and mechanically-grounded, cooperatively-controlled robots. Whilst these approaches have seen both commercial and clinical success, uptake of these robots remains moderate because of their high cost, large physical footprint and long setup times. More recently, researchers have moved toward developing hand-held robots that are completely ungrounded and manipulated by surgeons in free space, in a similar manner to how conventional instruments are handled. These devices provide specific functions that assist the surgeon in accomplishing tasks that are otherwise challenging with manual manipulation. Hand-held robots have the advantages of being compact and easily integrated into the normal surgical workflow since there is typically little or no setup time. Hand-held devices can also have a significantly reduced cost to healthcare providers as they do not necessitate the complex, multi degree-of-freedom linkages that grounded robots require. However, the development of such devices is faced with many technical challenges, including miniaturization, cost and sterility, control stability, inertial and gravity compensation and robust instrument tracking. This review presents the emerging technical trends in hand-held medical robots and future development opportunities for promoting their wider clinical uptake. PMID:24927713

  14. New Clothing for Handheld Devices

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2013-01-01

    Clothing is influenced by many factors, trends, and social happenings. Much of what is worn today had utilitarian roots in the past. In the activitiy presented in this article, students will have the opportunity to redesign clothing for new trends, in this case, the explosion of handheld electronic devices.

  15. Handheld Optical Coherence Tomography Scanner for Primary Care Diagnostics

    PubMed Central

    Jung, Woonggyu; Kim, Jeehyun; Jeon, Mansik; Chaney, Eric J.; Stewart, Charles N.

    2011-01-01

    The goal of this study is to develop an advanced point-of-care diagnostic instrument for use in a primary care office using handheld optical coherence tomography (OCT). This system has the potential to enable earlier detection of diseases and accurate image-based diagnostics. Our system was designed to be compact, portable, user-friendly, and fast, making it well suited for the primary care office setting. The unique feature of our system is a versatile handheld OCT imaging scanner which consists of a pair of computer-controlled galvanometer-mounted mirrors, interchangeable lens mounts, and miniaturized video camera. This handheld scanner has the capability to guide the physician in real time for finding suspicious regions to be imaged by OCT. In order to evaluate the performance and use of the handheld OCT scanner, the anterior chamber of a rat eye and in vivo human retina, cornea, skin, and tympanic membrane were imaged. Based on this feasibility study, we believe that this new type of handheld OCT device and system has the potential to be an efficient point-of-care imaging tool in primary care medicine. PMID:21134801

  16. Handheld optical coherence tomography scanner for primary care diagnostics.

    PubMed

    Jung, Woonggyu; Kim, Jeehyun; Jeon, Mansik; Chaney, Eric J; Stewart, Charles N; Boppart, Stephen A

    2011-03-01

    The goal of this study is to develop an advanced point-of-care diagnostic instrument for use in a primary care office using handheld optical coherence tomography (OCT). This system has the potential to enable earlier detection of diseases and accurate image-based diagnostics. Our system was designed to be compact, portable, user-friendly, and fast, making it well suited for the primary care office setting. The unique feature of our system is a versatile handheld OCT imaging scanner which consists of a pair of computer-controlled galvanometer-mounted mirrors, interchangeable lens mounts, and miniaturized video camera. This handheld scanner has the capability to guide the physician in real time for finding suspicious regions to be imaged by OCT. In order to evaluate the performance and use of the handheld OCT scanner, the anterior chamber of a rat eye and in vivo human retina, cornea, skin, and tympanic membrane were imaged. Based on this feasibility study, we believe that this new type of handheld OCT device and system has the potential to be an efficient point-of-care imaging tool in primary care medicine. PMID:21134801

  17. On-orbit performance of the Extended Gyrocompass Controller for the TOPEX/Poseidon spacecraft

    NASA Technical Reports Server (NTRS)

    Sanneman, P. A.; Lee, B. B.

    1993-01-01

    The paper describes the Earth Acquisition Mode Extended Gyrocompass Controller flown aboard the NASA-CNES TOPEX/Poseidon Attitude Determination and Control Subsystem spacecraft for providing highly accurate measurements of the surface elevations over all the ocean basins. Particular attention is given to the on-orbit performance of the Extended Gyrocompass Controller used during quaternion initialization and Update Filter convergence processing, both of these procedures requiring maintenance of the spacecraft attitude control and knowledge. The development of the Extended Gyrocompass control technique is reviewed, and the results of the on-orbit yaw attitude control and knowledge performance provided by this algorithm are presented.

  18. Performance status of a small robot-mounted or hand-held, solar-blind, standoff chemical, biological, and explosives (CBE) sensor

    NASA Astrophysics Data System (ADS)

    Hug, W. F.; Reid, R. D.; Bhartia, R.; Lane, A. L.

    2009-05-01

    Photon Systems and JPL are continuing development of a new technology robot-mounted or hand-held sensor for reagentless, short-range, standoff detection and identification of trace levels CBE materials on surfaces. This deep ultraviolet CBE sensor is the result of ongoing Army STTR and DTRA programs. The evolving 6 lb, 15W, lantern-size sensor can discriminate CBE from background clutter materials using a combination of deep UV excited resonance Raman (RR) and laser induced native fluorescence (LINF) emissions resulting from excitation by a new technology deep UV laser. Standoff excitation of suspicious packages, vehicles, persons, and other objects that may contain hazardous materials is accomplished using wavelengths below 250nm where RR and LINF emissions occupy distinctly different wavelength regions. This enables simultaneous detection of RR and LINF emissions with no spectral overlap or interference of LINF over RR or RR over LINF. The new eye-safe targeted ultraviolet chemical, biological, and explosives (TUCBE) sensor can detect and identify less than 1 μg/cm2 of explosives or 104 bacterial spores at 10 meters standoff, or 10 ng/cm2 of explosives or 102 bacterial spores/cm2 at 1 meter standoff. Detection and identification requires less than 1 ms and has a sample rate up to 20 Hz. Lower concentrations of contamination can be detected and identified as closer ranges and higher concentrations at longer ranges. The sensor is solar blind and can be operated in full daylight conditions as a result of excitation and detection in the deep UV and the use of a gated detection system.

  19. Texting while driving: is speech-based text entry less risky than handheld text entry?

    PubMed

    He, J; Chaparro, A; Nguyen, B; Burge, R J; Crandall, J; Chaparro, B; Ni, R; Cao, S

    2014-11-01

    Research indicates that using a cell phone to talk or text while maneuvering a vehicle impairs driving performance. However, few published studies directly compare the distracting effects of texting using a hands-free (i.e., speech-based interface) versus handheld cell phone, which is an important issue for legislation, automotive interface design and driving safety training. This study compared the effect of speech-based versus handheld text entries on simulated driving performance by asking participants to perform a car following task while controlling the duration of a secondary text-entry task. Results showed that both speech-based and handheld text entries impaired driving performance relative to the drive-only condition by causing more variation in speed and lane position. Handheld text entry also increased the brake response time and increased variation in headway distance. Text entry using a speech-based cell phone was less detrimental to driving performance than handheld text entry. Nevertheless, the speech-based text entry task still significantly impaired driving compared to the drive-only condition. These results suggest that speech-based text entry disrupts driving, but reduces the level of performance interference compared to text entry with a handheld device. In addition, the difference in the distraction effect caused by speech-based and handheld text entry is not simply due to the difference in task duration. PMID:25089769

  20. Hand-Held Ultrasonic Instrument for Reading Matrix Symbols

    NASA Technical Reports Server (NTRS)

    Schramm, Harry F.; Kula, John P.; Gurney, John W.; Lior, Ephraim D.

    2008-01-01

    A hand-held instrument that would include an ultrasonic camera has been proposed as an efficient means of reading matrix symbols. The proposed instrument could be operated without mechanical raster scanning. All electronic functions from excitation of ultrasonic pulses through final digital processing for decoding matrix symbols would be performed by dedicated circuitry within the single, compact instrument housing.

  1. Visual SLAM for Handheld Monocular Endoscope.

    PubMed

    Grasa, Óscar G; Bernal, Ernesto; Casado, Santiago; Gil, Ismael; Montiel, J M M

    2014-01-01

    Simultaneous localization and mapping (SLAM) methods provide real-time estimation of 3-D models from the sole input of a handheld camera, routinely in mobile robotics scenarios. Medical endoscopic sequences mimic a robotic scenario in which a handheld camera (monocular endoscope) moves along an unknown trajectory while observing an unknown cavity. However, the feasibility and accuracy of SLAM methods have not been extensively validated with human in vivo image sequences. In this work, we propose a monocular visual SLAM algorithm tailored to deal with medical image sequences in order to provide an up-to-scale 3-D map of the observed cavity and the endoscope trajectory at frame rate. The algorithm is validated over synthetic data and human in vivo sequences corresponding to 15 laparoscopic hernioplasties where accurate ground-truth distances are available. It can be concluded that the proposed procedure is: 1) noninvasive, because only a standard monocular endoscope and a surgical tool are used; 2) convenient, because only a hand-controlled exploratory motion is needed; 3) fast, because the algorithm provides the 3-D map and the trajectory in real time; 4) accurate, because it has been validated with respect to ground-truth; and 5) robust to inter-patient variability, because it has performed successfully over the validation sequences. PMID:24107925

  2. Dependence of Adaptive Cross-correlation Algorithm Performance on the Extended Scene Image Quality

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin

    2008-01-01

    Recently, we reported an adaptive cross-correlation (ACC) algorithm to estimate with high accuracy the shift as large as several pixels between two extended-scene sub-images captured by a Shack-Hartmann wavefront sensor. It determines the positions of all extended-scene image cells relative to a reference cell in the same frame using an FFT-based iterative image-shifting algorithm. It works with both point-source spot images as well as extended scene images. We have demonstrated previously based on some measured images that the ACC algorithm can determine image shifts with as high an accuracy as 0.01 pixel for shifts as large 3 pixels, and yield similar results for both point source spot images and extended scene images. The shift estimate accuracy of the ACC algorithm depends on illumination level, background, and scene content in addition to the amount of the shift between two image cells. In this paper we investigate how the performance of the ACC algorithm depends on the quality and the frequency content of extended scene images captured by a Shack-Hatmann camera. We also compare the performance of the ACC algorithm with those of several other approaches, and introduce a failsafe criterion for the ACC algorithm-based extended scene Shack-Hatmann sensors.

  3. Dependence of adaptive cross-correlation algorithm performance on the extended scene image quality

    NASA Astrophysics Data System (ADS)

    Sidick, Erkin

    2008-08-01

    Recently, we reported an adaptive cross-correlation (ACC) algorithm to estimate with high accuracy the shift as large as several pixels between two extended-scene sub-images captured by a Shack-Hartmann wavefront sensor. It determines the positions of all extended-scene image cells relative to a reference cell in the same frame using an FFT-based iterative image-shifting algorithm. It works with both point-source spot images as well as extended scene images. We have demonstrated previously based on some measured images that the ACC algorithm can determine image shifts with as high an accuracy as 0.01 pixel for shifts as large 3 pixels, and yield similar results for both point source spot images and extended scene images. The shift estimate accuracy of the ACC algorithm depends on illumination level, background, and scene content in addition to the amount of the shift between two image cells. In this paper we investigate how the performance of the ACC algorithm depends on the quality and the frequency content of extended scene images captured by a Shack-Hatmann camera. We also compare the performance of the ACC algorithm with those of several other approaches, and introduce a failsafe criterion for the ACC algorithm-based extended scene Shack-Hatmann sensors.

  4. Performance of Extended Local Clustering Organization (LCO) for Large Scale Job-Shop Scheduling Problem (JSP)

    NASA Astrophysics Data System (ADS)

    Konno, Yohko; Suzuki, Keiji

    This paper describes an approach to development of a solution algorithm of a general-purpose for large scale problems using “Local Clustering Organization (LCO)” as a new solution for Job-shop scheduling problem (JSP). Using a performance effective large scale scheduling in the study of usual LCO, a solving JSP keep stability induced better solution is examined. In this study for an improvement of a performance of a solution for JSP, processes to a optimization by LCO is examined, and a scheduling solution-structure is extended to a new solution-structure based on machine-division. A solving method introduced into effective local clustering for the solution-structure is proposed as an extended LCO. An extended LCO has an algorithm which improves scheduling evaluation efficiently by clustering of parallel search which extends over plural machines. A result verified by an application of extended LCO on various scale of problems proved to conduce to minimizing make-span and improving on the stable performance.

  5. Real-time focal stack compositing for handheld mobile cameras

    NASA Astrophysics Data System (ADS)

    Solh, Mashhour

    2013-03-01

    Extending the depth of field using a single lens camera on a mobile device can be achieved by capturing a set of images each focused at a different depth or focal stack then combine these samples of the focal stack to form a single all-in-focus image or an image refocused at a desired depth of field. Focal stack compositing in real time for a handheld mobile camera has many challenges including capturing, processing power, handshaking, rolling shutter artifacts, occlusion, and lens zoom effect. In this paper, we describe a system for a real time focal stack compositing system for handheld mobile device with an alignment and compositing algorithms. We will also show all-in-focus images captured and processed by a cell phone camera running on Android OS.

  6. An Evaluation of Student Performance Based Upon Utilization of Extended Opportunity Programs and Services.

    ERIC Educational Resources Information Center

    Lee, Clarence A.; West, John R.

    Disadvantaged students need more than financial support if they are to function well in a community college. The hypothesis of this study is that non-traditional students who take advantage of the total Extended Opportunity Programs and Services (EOPS) package will perform better academically than those who utilize only financial aid. A review of…

  7. School Reading Performance and the Extended School Day Policy in Florida. REL 2016-141

    ERIC Educational Resources Information Center

    Folsom, Jessica Sidler; Petscher, Yaacov; Osborne-Lampkin, La'Tara; Cooley, Stephan; Herrera, Sarah; Partridge, Mark; Smith, Kevin

    2016-01-01

    Florida law requires the 100 lowest performing elementary schools in reading to extend the school day by one hour to provide supplemental reading instruction. This study found that those schools were smaller than other elementary schools and served a higher proportion of racial/ethnic minority students and students eligible for the school lunch…

  8. Handheld advanced nucleic acid analyzer

    NASA Astrophysics Data System (ADS)

    Benett, William J.; Richards, James B.; Stratton, Paul; Hadley, Dean R.; Bodtker, Brian H.; Nasarabadi, Shanavaz L.; Milanovich, Fred P.; Mariella, Raymond P., Jr.; Koopman, Ronald P.; Belgrader, Philip

    2000-12-01

    There is a growing need for portable, lightweight, battery operated instruments capable of detecting and identifying bio-warfare and bio-terrorism agents in the field. To address this need, we have developed a handheld PCR instrument. LLNLs advanced thermal cycling technology and expertise with portable, field tested biological instrumentation, combined with the development of real-time, fluorescence based PCR assays, has enabled the development of a very portable, versatile, power efficient PCR instrument with a simplified operating system designed for use by first responders. The heart of the instrument is the sample module, which incorporates the advanced silicon thermal cycler developed at LLNL.

  9. Data for Users of Handheld Ion Mobility Spectrometers

    SciTech Connect

    Keith A. Daum; Sandra L. Fox

    2008-05-01

    Chemical detection technology end-user surveys conducted by Idaho National Laboratory (INL) in 2005 and 2007 indicated that first responders believed manufacturers’ claims for instruments sometimes were not supported in field applications, and instruments sometimes did not meet their actual needs. Based on these findings, the Department of Homeland Security (DHS) asked INL to conduct a similar survey for handheld ion mobility spectrometers (IMS), which are used by a broad community of first responders as well as for other applications. To better access this broad community, the INL used the Center for Technology Commercialization, Inc. (CTC), Public Safety Technology Center (PSTC) to set up an online framework to gather information from users of handheld IMS units. This framework (Survey Monkey) was then used to perform an online Internet survey, augmented by e-mail prompts, to get information from first responders and personnel from various agencies about their direct experience with handheld IMS units. Overall, 478 individuals responded to the survey. Of these, 174 respondents actually owned a handheld IMS. Performance and satisfaction data from these 174 respondents are captured in this report. The survey identified the following observations: • The most common IMS unit used by respondents was the Advanced Portable Detector (APD 2000), followed by ChemRae, Sabre 4000, Sabre 2000, Draeger Multi IMS, Chemical Agent Monitor-2, Chemical Agent Monitor, Vapor Tracer, and Vapor Tracer 2. • The primary owners were HazMat teams (20%), fire services (14%), local police (12%), and sheriffs’ departments (9%). • IMS units are seldom used as part of an integrated system for detecting and identifying chemicals but instead are used independently. • Respondents are generally confused about the capabilities of their IMS unit. This is probably a result of lack of training. • Respondents who had no training or fewer than 8 hours were not satisfied with the overall

  10. SWATH Mass Spectrometry Performance Using Extended Peptide MS/MS Assay Libraries.

    PubMed

    Wu, Jemma X; Song, Xiaomin; Pascovici, Dana; Zaw, Thiri; Care, Natasha; Krisp, Christoph; Molloy, Mark P

    2016-07-01

    The use of data-independent acquisition methods such as SWATH for mass spectrometry based proteomics is usually performed with peptide MS/MS assay libraries which enable identification and quantitation of peptide peak areas. Reference assay libraries can be generated locally through information dependent acquisition, or obtained from community data repositories for commonly studied organisms. However, there have been no studies performed to systematically evaluate how locally generated or repository-based assay libraries affect SWATH performance for proteomic studies. To undertake this analysis, we developed a software workflow, SwathXtend, which generates extended peptide assay libraries by integration with a local seed library and delivers statistical analysis of SWATH-quantitative comparisons. We designed test samples using peptides from a yeast extract spiked into peptides from human K562 cell lysates at three different ratios to simulate protein abundance change comparisons. SWATH-MS performance was assessed using local and external assay libraries of varying complexities and proteome compositions. These experiments demonstrated that local seed libraries integrated with external assay libraries achieve better performance than local assay libraries alone, in terms of the number of identified peptides and proteins and the specificity to detect differentially abundant proteins. Our findings show that the performance of extended assay libraries is influenced by the MS/MS feature similarity of the seed and external libraries, while statistical analysis using multiple testing corrections increases the statistical rigor needed when searching against large extended assay libraries. PMID:27161445

  11. Envisioning the Handheld-Centric Classroom

    ERIC Educational Resources Information Center

    Norris, Cathleen; Soloway, Elliot

    2004-01-01

    While appropriate as an initial focus, it is time that the educational community move beyond an emphasis on 1:1 computing (each child having his/her own personal computer) to a vision of a handheld-centric classroom, where each child not only has his/her own personal, handheld computer, but also has access to networked PCs, probeware, digital…

  12. Wireless Handhelds to Support Clinical Nursing Practicum

    ERIC Educational Resources Information Center

    Wu, Cheng-Chih; Lai, Chin-Yuan

    2009-01-01

    This paper reports our implementation and evaluation of a wireless handheld learning environment used to support a clinical nursing practicum course. The learning environment was designed so that nursing students could use handhelds for recording information, organizing ideas, assessing patients, and also for interaction and collaboration with…

  13. Handheld Computer Software for School Nurses

    ERIC Educational Resources Information Center

    Bergren, Martha Dewey; Murphy, Elizabeth Ann

    2005-01-01

    School nurses used computers in the 1980s, the Internet in the 1990s, and are embracing handheld computers in the first decade of the 21st century to improve their practice. The purpose of this article is to provide information about handheld computers and software applications that school nurses can use in day-to-day, emergency, and disaster…

  14. Handheld Computers: A Boon for Principals

    ERIC Educational Resources Information Center

    Brazell, Wayne

    2005-01-01

    As I reflect on my many years as an elementary school principal, I realize how much more effective I would have been if I had owned a wireless handheld computer. This relatively new technology can provide considerable assistance to today?s principals and recent advancements have increased its functions and capacity. Handheld computers are…

  15. Choosing a Hand-Held Inventory Device

    ERIC Educational Resources Information Center

    Green, Lois; Hughes, Janet; Neff, Verne; Notartomas, Trish

    2008-01-01

    In spring of 2006, a task force was charged to look at the feasibility of acquiring hand-held inventory devices for the Pennsylvania State University Libraries (PSUL). The task force's charge was not to look at the whole concept of doing an inventory, but rather to focus on the feasibility of acquiring hand-held devices to use in an inventory.…

  16. Characterization of desalination performance of CDI electrode materials using extended electroimpedance spectroscopy

    NASA Astrophysics Data System (ADS)

    Rios Perez, Carlos; Wilkes, Ellen; Hidrovo, Carlos

    2015-11-01

    A comprehensive characterization of porous materials developed for capacitive deionization (CDI) electrodes is very important for the future of this desalination technology. Traditional methods assess the adsorption performance of the electrodes using gas adsorption techniques and electrochemical tests. However, these results fail at comparing quantitatively the performance of different electrode materials. This presentation proposes using a combination of extended electroimpedance spectroscopy (EIS) tests and BET analysis to appraise the amount of salt adsorbed in a flow-by CDI system. The extended EIS experiments were analyzed using an equivalent circuit with three characteristic tiers that represent the dominant ionic migration processes with different time-scales: electro adsorption of ions in the micropores, migration of ion from bulk solution through macropores, adsorption of ions from the bulk solution. The results obtained show a very good agreement between characterization and desalination performance experiments for three commercial electrodes with different structure topology.

  17. Handheld erythema and bruise detector

    NASA Astrophysics Data System (ADS)

    Kong, Linghua; Sprigle, Stephen; Duckworth, Mark G.; Yi, Dingrong; Caspall, Jayme J.; Wang, Jiwu; Zhao, Futing

    2008-03-01

    Visual inspection of intact skin is commonly used when assessing persons for pressure ulcers and bruises. Melanin masks skin discoloration hindering visual inspection in people with darkly pigmented skin. The objective of the project is to develop a point of care technology capable of detecting erythema and bruises in persons with darkly pigmented skin. Two significant hardware components, a color filter array and illumination system have been developed and tested. The color filter array targets four defined wavelengths and has been designed to fit onto a CMOS sensor. The crafting process generates a multilayer film on a glass substrate using vacuum ion beam splitter and lithographic techniques. The illumination system is based upon LEDs and targets these same pre-defined wavelengths. Together, these components are being used to create a small, handheld multispectral imaging device. Compared to other multi spectral technologies (multi prisms, optical-acoustic crystal and others), the design provides simple, low cost instrumentation that has many potential multi spectral imaging applications which require a handheld detector.

  18. Video Browsing on Handheld Devices

    NASA Astrophysics Data System (ADS)

    Hürst, Wolfgang

    Recent improvements in processing power, storage space, and video codec development enable users now to playback video on their handheld devices in a reasonable quality. However, given the form factor restrictions of such a mobile device, screen size still remains a natural limit and - as the term "handheld" implies - always will be a critical resource. This is not only true for video but any data that is processed on such devices. For this reason, developers have come up with new and innovative ways to deal with large documents in such limited scenarios. For example, if you look at the iPhone, innovative techniques such as flicking have been introduced to skim large lists of text (e.g. hundreds of entries in your music collection). Automatically adapting the zoom level to, for example, the width of table cells when double tapping on the screen enables reasonable browsing of web pages that have originally been designed for large, desktop PC sized screens. A multi touch interface allows you to easily zoom in and out of large text documents and images using two fingers. In the next section, we will illustrate that advanced techniques to browse large video files have been developed in the past years, as well. However, if you look at state-of-the-art video players on mobile devices, normally just simple, VCR like controls are supported (at least at the time of this writing) that only allow users to just start, stop, and pause video playback. If supported at all, browsing and navigation functionality is often restricted to simple skipping of chapters via two single buttons for backward and forward navigation and a small and thus not very sensitive timeline slider.

  19. Extending the detectability index to quantitative imaging performance: applications in tomosynthesis and CT

    NASA Astrophysics Data System (ADS)

    Richard, Samuel; Chen, Baiyu; Samei, Ehsan

    2010-04-01

    This study aimed to extend Fourier-based imaging metrics for the modeling of quantitative imaging performance. Breast tomosynthesis was used as a platform for investigating acquisition and processing parameters (e.g., acquisition angle and dose) that can significantly affect 3D signal and noise, and consequently quantitative imaging performance. The detectability index was computed using the modulation transfer function and noise-power spectrum combined with a Fourier description of imaging task. Three imaging tasks were considered: detection, area estimation (in coronal slice), and volume estimation of a 4 mm diameter spherical target. Task functions for size estimation were generated by using measured performance of the maximum-likelihood estimator as training data. The detectability index computed with the size estimation tasks correlated well with precision measurements for area and volume estimation over a fairly broad range of imaging conditions and provided a meaningful figure of merit for quantitative imaging performance. Furthermore, results highlighted that optimal breast tomosynthesis acquisition parameters depend significantly on imaging task. Mass detection was optimal at an acquisition angle of 85° while area and volume estimation for the same mass were optimal at ~100° and 125° acquisition angles, respectively. These findings provide key initial validation that the Fourier-based detectability index extended to estimation tasks can represent a meaningful metric and predictor of quantitative imaging performance.

  20. Does the inclusion of protease inhibitors in the insemination extender affect rabbit reproductive performance?

    PubMed

    Casares-Crespo, L; Vicente, J S; Talaván, A M; Viudes-de-Castro, M P

    2016-03-15

    The bioavailability of buserelin acetate when added to the seminal dose appears to be determined by the activity of the existing aminopeptidases. Thus, the addition of aminopeptidase inhibitors to rabbit semen extenders could be a solution to decrease the hormone degradation. This study was conducted to evaluate the effect of the protease activity inhibition on rabbit semen quality parameters and reproductive performance after artificial insemination. Seminal quality was not affected by the incubation with protease inhibitors, being the values of motility, viability, and acrosome integrity not significantly different between the protease inhibitors and the control group. In addition, seminal plasma aminopeptidase activity was inhibited in a 55.1% by the protease inhibitors. On the other hand, regarding the effect of protease inhibitors on reproductive performance, our results showed that the presence of protease inhibitors affected the prolificacy rate (9.2 ± 0.26 and 9.3 ± 0.23 vs. 8.2 ± 0.22 total born per litter for negative control, positive control, and aminopeptidase inhibitors group, respectively; P < 0.05), having this group one kit less per delivery. We conclude that the addition of a wide variety of protease inhibitors in the rabbit semen extender negatively affects prolificacy rate. Therefore, the development of new extenders with specific aminopeptidase inhibitors would be one of the strategies to increase the bioavailability of GnRH analogues without affecting the litter size. PMID:26639641

  1. Performance Characterization of a Microchannel Liquid/Liquid Heat Exchanger Throughout an Extended Duration Life Test

    NASA Technical Reports Server (NTRS)

    Sheth, Rubik B.; Stephan, Ryan A.; Hawkins-Reynolds Ebony

    2011-01-01

    Liquid/Liquid Heat Exchangers (L/L HX) are an integral portion of any spacecraft active thermal control system. For this study the X-38 L/L HX was used as a baseline. As detailed in a previous ICES manuscript, NASA paired with Pacific Northwest National Laboratory to develop a Microchannel L/L HX (MHX). This microchannel HX was designed to meet the same performance characteristics as the aforementioned X-38 HX. The as designed Microchannel HX has a 26% and 60% reduction in mass and volume, respectively. Due to the inherently smaller flow passages the design team was concerned about fouling affecting performance during extended missions. To address this concern, NASA has developed a test stand and is currently performing an 18 month life test on the MHX. This report will detail the up-to-date performance of the MHX during life testing.

  2. Performance and field tests of a handheld Compton camera using 3-D position-sensitive scintillators coupled to multi-pixel photon counter arrays

    NASA Astrophysics Data System (ADS)

    Kishimoto, A.; Kataoka, J.; Nishiyama, T.; Fujita, T.; Takeuchi, K.; Okochi, H.; Ogata, H.; Kuroshima, H.; Ohsuka, S.; Nakamura, S.; Hirayanagi, M.; Adachi, S.; Uchiyama, T.; Suzuki, H.

    2014-11-01

    After the nuclear disaster in Fukushima, radiation decontamination has become particularly urgent. To help identify radiation hotspots and ensure effective decontamination operation, we have developed a novel Compton camera based on Ce-doped Gd3Al2Ga3O12 scintillators and multi-pixel photon counter (MPPC) arrays. Even though its sensitivity is several times better than that of other cameras being tested in Fukushima, we introduce a depth-of-interaction (DOI) method to further improve the angular resolution. For gamma rays, the DOI information, in addition to 2-D position, is obtained by measuring the pulse-height ratio of the MPPC arrays coupled to ends of the scintillator. We present the detailed performance and results of various field tests conducted in Fukushima with the prototype 2-D and DOI Compton cameras. Moreover, we demonstrate stereo measurement of gamma rays that enables measurement of not only direction but also approximate distance to radioactive hotspots.

  3. Effect of shortening kraft pulping integrated with extended oxygen delignification on biorefinery process performance of eucalyptus.

    PubMed

    Li, Jing; Zhang, Chunyun; Hu, Huichao; Chai, Xin-Sheng

    2016-02-01

    The aim of this work was to study the impact of shortening kraft pulping (KP) process integrated with extended oxygen delignification (OD) on the biorefinery process performance of eucalyptus. Data showed that using kraft pulps with high kappa number could improve the delignification efficiency of OD, reduce hexenuronic acid formation in kraft pulps. Pulp viscosity for a target kappa number of ∼10 was comparable to that obtained from conventional KP and OD process. The energy and alkali consumption in the integrated biorefinery process could be optimized when using a KP pulp with kappa number of ∼27. The process could minimize the overall methanol formation, but greater amounts of carbonate and oxalate were formed. The information from this study will be helpful to the future implementation of short-time KP integrated with extended OD process in actual pulp mill applications for biorefinery, aiming at further improvement in the biorefinery effectiveness of hardwood. PMID:26706725

  4. Augmented Reality Simulations on Handheld Computers

    ERIC Educational Resources Information Center

    Squire, Kurt; Klopfer, Eric

    2007-01-01

    Advancements in handheld computing, particularly its portability, social interactivity, context sensitivity, connectivity, and individuality, open new opportunities for immersive learning environments. This article articulates the pedagogical potential of augmented reality simulations in environmental engineering education by immersing students in…

  5. Development of a remote handheld cardiac arrhythmia monitor.

    PubMed

    Singh, Swaroop S; Hsiao, Henry S

    2006-01-01

    In this paper we present the design and development of a real-time remote handheld cardiac arrhythmic monitoring system (RCAM). A client-server model based on Internet protocols was used. ECG data was transmitted from the remote handheld client to a centralized server, where the QRS and premature ventricular contraction detection algorithms were implemented and graded depending on the number and pattern of PVCs present. The QRS sensitivity and specificity on ECG records from Physionet archives in absence of arrhythmia was 100% and 99.62%, while in presence of arrhythmia was 99.34% and 99.31%. The average 'negative time' measured on ventricular tachyarrhythmia records was 92 seconds. The RCAM can provide remote detection of cardiac abnormalities and give specific diagnosis and recommendations of actions to be taken immediately. The limitation due to the inability of the PDA to perform complex computations was overcome by the use of the remote server. PMID:17947043

  6. Extended performance solar electric propulsion thrust system study. Volume 2: Baseline thrust system

    NASA Technical Reports Server (NTRS)

    Poeschel, R. L.; Hawthorne, E. I.

    1977-01-01

    Several thrust system design concepts were evaluated and compared using the specifications of the most advanced 30- cm engineering model thruster as the technology base. Emphasis was placed on relatively high-power missions (60 to 100 kW) such as a Halley's comet rendezvous. The extensions in thruster performance required for the Halley's comet mission were defined and alternative thrust system concepts were designed in sufficient detail for comparing mass, efficiency, reliability, structure, and thermal characteristics. Confirmation testing and analysis of thruster and power-processing components were performed, and the feasibility of satisfying extended performance requirements was verified. A baseline design was selected from the alternatives considered, and the design analysis and documentation were refined. The baseline thrust system design features modular construction, conventional power processing, and a concentractor solar array concept and is designed to interface with the space shuttle.

  7. Extended performance solar electric propulsion thrust system study. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Poeschel, R. L.; Hawthorne, E. I.

    1977-01-01

    Several thrust system design concepts were evaluated and compared using the specifications of the most advanced 30 cm engineering model thruster as the technology base. The extensions in thruster performance required for the Halley's comet mission were defined and alternative thrust system concepts were designed. Confirmation testing and analysis of thruster and power-processing components were performed, and the feasibility of satisfying extended performance requirements was verified. A baseline design was selected from the alternatives considered, and the design analysis and documentation were refined. A program development plan was formulated that outlines the work structure considered necessary for developing, qualifying, and fabricating the flight hardware for the baseline thrust system within the time frame of a project to rendezvous with Halley's comet. An assessment was made of the costs and risks associated with a baseline thrust system as provided to the mission project under this plan. Critical procurements and interfaces were identified and defined. Results are presented.

  8. Extended performance solar electric propulsion thrust system study. Volume 4: Thruster technology evaluation

    NASA Technical Reports Server (NTRS)

    Poeschel, R. L.; Hawthorne, E. I.; Weisman, Y. C.; Frisman, M.; Benson, G. C.; Mcgrath, R. J.; Martinelli, R. M.; Linsenbardt, T. L.; Beattie, J. R.

    1977-01-01

    Several thrust system design concepts were evaluated and compared using the specifications of the most advanced 30 cm engineering model thruster as the technology base. Emphasis was placed on relatively high power missions (60 to 100 kW) such as a Halley's comet rendezvous. The extensions in thruster performance required for the Halley's comet mission were defined and alternative thrust system concepts were designed in sufficient detail for comparing mass, efficiency, reliability, structure, and thermal characteristics. Confirmation testing and analysis of thruster and power processing components were performed, and the feasibility of satisfying extended performance requirements was verified. A baseline design was selected from the alternatives considered, and the design analysis and documentation were refined. The baseline thrust system design features modular construction, conventional power processing, and a concentrator solar array concept and is designed to interface with the Space Shuttle.

  9. Deterioration of Neurobehavioral Performance in Resident Physicians During Repeated Exposure to Extended Duration Work Shifts

    PubMed Central

    Anderson, Clare; Sullivan, Jason P.; Flynn-Evans, Erin E.; Cade, Brian E.; Czeisler, Charles A.; Lockley, Steven W.

    2012-01-01

    Study Objectives: Although acute sleep loss during 24- to 30-h extended duration work shifts (EDWS) has been shown to impair the performance of resident physicians, little is known about the effects of cumulative sleep deficiency on performance during residency training. Chronic sleep restriction induces a gradual degradation of neurobehavioral performance and exacerbates the effects of acute sleep loss in the laboratory, yet the extent to which this occurs under real-world conditions is unknown. In this study, the authors quantify the time course of neurobehavioral deterioration due to repeated exposure to EDWS during a 3-week residency rotation. Design: A prospective, repeated-measures, within-subject design. Setting: Medical and cardiac intensive care units, Brigham and Women's Hospital, Boston, MA. Participants: Thirty-four postgraduate year one resident physicians (23 males; age 28.0 ± 1.83 (standard deviation) years) Measurements and Results: Residents working a 3-week Q3 schedule (24- to 30-h work shift starts every 3rd day), consisting of alternating 24- to 30-h (EDWS) and approximately 8-h shifts, underwent psychomotor vigilance testing before, during, and after each work shift. Mean response time, number of lapses, and slowest 10% of responses were calculated for each test. Residents also maintained daily sleep/wake/work logs. EDWS resulted in cumulative sleep deficiency over the 21-day rotation (6.3 h sleep obtained per day; average 2.3 h sleep obtained per extended shift). Response times deteriorated over a single 24- to 30-h shift (P < 0.0005), and also cumulatively with each successive EDWS: Performance on the fifth and sixth shift was significantly worse than on the first shift (P < 0.01). Controlling for time of day, there was a significant acute (time on shift) and chronic (successive EDWS) interaction on psychomotor vigilance testing response times (P < 0.05). Conclusions: Chronic sleep deficiency caused progressive degradation in residents

  10. Handheld interface for miniature sensors

    NASA Astrophysics Data System (ADS)

    Kedia, Sunny; Samson, Scott A.; Farmer, Andrew; Smith, Matthew C.; Fries, David; Bhansali, Shekhar

    2005-02-01

    Miniaturization of laboratory sensors has been enabled by continued evolution of technology. Field portable systems are often desired, because they reduce sample handling, provide rapid feedback capability, and enhance convenience. Fieldable sensor systems should include a method for initiating the analysis, storing and displaying the results, while consuming minimal power and being compact and portable. Low cost will allow widespread usage of these systems. In this paper, we discuss a reconfigurable Personal Data Assistant (PDA) based control and data collection system for use with miniature sensors. The system is based on the Handspring visor PDA and a custom designed motherboard, which connects directly to the PDA microprocessor. The PDA provides a convenient and low cost graphical user interface, moderate processing capability, and integrated battery power. The low power motherboard provides the voltage levels, data collection, and input/output (I/O) capabilities required by many MEMS and miniature sensors. These capabilities are relayed to connectors, where an application specific daughterboard is attached. In this paper, two applications are demonstrated. First, a handheld nucleic acid sequence-based amplification (NASBA) detection sensor consisting of a heated and optical fluorescence detection system is discussed. Second, an electrostatically actuated MEMS micro mirror controller is realized.

  11. Effects of extended lay-off periods on performance and operator trust under adaptable automation.

    PubMed

    Chavaillaz, Alain; Wastell, David; Sauer, Jürgen

    2016-03-01

    Little is known about the long-term effects of system reliability when operators do not use a system during an extended lay-off period. To examine threats to skill maintenance, 28 participants operated twice a simulation of a complex process control system for 2.5 h, with an 8-month retention interval between sessions. Operators were provided with an adaptable support system, which operated at one of the following reliability levels: 60%, 80% or 100%. Results showed that performance, workload, and trust remained stable at the second testing session, but operators lost self-confidence in their system management abilities. Finally, the effects of system reliability observed at the first testing session were largely found again at the second session. The findings overall suggest that adaptable automation may be a promising means to support operators in maintaining their performance at the second testing session. PMID:26603139

  12. Toward Automated Intraocular Laser Surgery Using a Handheld Micromanipulator

    PubMed Central

    Yang, Sungwook; MacLachlan, Robert A.; Riviere, Cameron N.

    2014-01-01

    This paper presents a technique for automated intraocular laser surgery using a handheld micromanipulator known as Micron. The novel handheld manipulator enables the automated scanning of a laser probe within a cylinder of 4 mm long and 4 mm in diameter. For the automation, the surface of the retina is reconstructed using a stereomicroscope, and then preplanned targets are placed on the surface. The laser probe is precisely located on the target via visual servoing of the aiming beam, while maintaining a specific distance above the surface. In addition, the system is capable of tracking the surface of the eye in order to compensate for any eye movement introduced during the operation. We compared the performance of the automated scanning using various control thresholds, in order to find the most effective threshold in terms of accuracy and speed. Given the selected threshold, we conducted the handheld operation above a fixed target surface. The average error and execution time are reduced by 63.6% and 28.5%, respectively, compared to the unaided trials. Finally, the automated laser photocoagulation was demonstrated also in an eye phantom, including compensation for the eye movement. PMID:25893135

  13. Analysis of Accuracy in Pointing with Redundant Hand-held Tools: A Geometric Approach to the Uncontrolled Manifold Method

    PubMed Central

    Campolo, Domenico; Widjaja, Ferdinan; Xu, Hong; Ang, Wei Tech; Burdet, Etienne

    2013-01-01

    This work introduces a coordinate-independent method to analyse movement variability of tasks performed with hand-held tools, such as a pen or a surgical scalpel. We extend the classical uncontrolled manifold (UCM) approach by exploiting the geometry of rigid body motions, used to describe tool configurations. In particular, we analyse variability during a static pointing task with a hand-held tool, where subjects are asked to keep the tool tip in steady contact with another object. In this case the tool is redundant with respect to the task, as subjects control position/orientation of the tool, i.e. 6 degrees-of-freedom (dof), to maintain the tool tip position (3dof) steady. To test the new method, subjects performed a pointing task with and without arm support. The additional dof introduced in the unsupported condition, injecting more variability into the system, represented a resource to minimise variability in the task space via coordinated motion. The results show that all of the seven subjects channeled more variability along directions not directly affecting the task (UCM), consistent with previous literature but now shown in a coordinate-independent way. Variability in the unsupported condition was only slightly larger at the endpoint but much larger in the UCM. PMID:23592956

  14. [Hand-held echocardiography in clinical practice].

    PubMed

    Mondillo, Sergio; Galderisi, Maurizio

    2005-05-01

    In the last years the industry has created echocardiographic portable machines of reduced size, available for a growing number of operators. After the first experiences of the '70s, hand-held echocardiography (HHE) is earned interesting commercial positions. The transportability of these machines allows to perform examinations outside the echo-lab and provides diagnostic information in heterogeneous locations such as intensive care unit, emergency room and outpatient structures, at the bedside and even in ambulance. HHE can be useful for detection of several pathologies including aortic aneurysms and left ventricular hypertrophy, regional wall motion abnormalities, pericardial and pleural effusion. To date, four main kinds of HHE can be distinguished: a first, high-cost variety, including miniaturized machines, equipped with instrumentations of standard echocardiography and even new softwares for tissue Doppler and myocardial contrast echocardiography; a second kind of machines of high level but not miniaturized; a third (intermediate level and low cost), and a fourth one (basic level and very low cost), including "cardioscopes" corresponding to the ultrasound stethoscope, able to complete efficaciously the clinical examination. The introduction of HHE opens controversy about its diagnostic accuracy, the opportunity to establish the clinical scenario where it should be utilized and the identification of the potential users and the needed competence level. Preliminary experiences show the possibility of improving and anticipating the diagnosis of several cardiac diseases but also the need to plan specific ultrasound training to avoid inappropriate use of HHE. PMID:15934422

  15. Performance Enhancement for a GPS Vector-Tracking Loop Utilizing an Adaptive Iterated Extended Kalman Filter

    PubMed Central

    Chen, Xiyuan; Wang, Xiying; Xu, Yuan

    2014-01-01

    This paper deals with the problem of state estimation for the vector-tracking loop of a software-defined Global Positioning System (GPS) receiver. For a nonlinear system that has the model error and white Gaussian noise, a noise statistics estimator is used to estimate the model error, and based on this, a modified iterated extended Kalman filter (IEKF) named adaptive iterated Kalman filter (AIEKF) is proposed. A vector-tracking GPS receiver utilizing AIEKF is implemented to evaluate the performance of the proposed method. Through road tests, it is shown that the proposed method has an obvious accuracy advantage over the IEKF and Adaptive Extended Kalman filter (AEKF) in position determination. The results show that the proposed method is effective to reduce the root-mean-square error (RMSE) of position (including longitude, latitude and altitude). Comparing with EKF, the position RMSE values of AIEKF are reduced by about 45.1%, 40.9% and 54.6% in the east, north and up directions, respectively. Comparing with IEKF, the position RMSE values of AIEKF are reduced by about 25.7%, 19.3% and 35.7% in the east, north and up directions, respectively. Compared with AEKF, the position RMSE values of AIEKF are reduced by about 21.6%, 15.5% and 30.7% in the east, north and up directions, respectively. PMID:25502124

  16. Performance-based seismic assessment of a large diameter extended pile shaft in a cohesionless soil

    NASA Astrophysics Data System (ADS)

    Ghotbi, Abdoul R.

    2015-03-01

    The seismic behavior of a large diameter extended pile shaft founded on a dense sandy site is investigated in this paper. First, a deterministic analysis is conducted including both nonlinear dynamic analysis (NDA) and pushover analysis to gain insights into the behavior of the pile and make sure an appropriate modeling technique is utilized. Then a probabilistic analysis is performed using the results of NDA for various demands. To this end a set of 40 pulse-like ground motions are picked and subsequently 40 nonlinear dynamic and pushover analyses are performed. The data obtained from NDA are used to generate probabilistic seismic demand model (PSDM) plots and consequently the median line and dispersion for each plot are computed. The NDA and pushover data are also plotted against each other to find out to what extent they are correlated. These operations are done for various engineering demand parameters (EDPs). A sensitivity analysis is done to pick the most appropriate intensity measure (IM) which would cause a minimum dispersion in PSDM plots out of 7 different IMs. Peak ground acceleration (PGA) is found to be the most appropriate IM. Pushover coefficient equations as a function of PGA are proposed which can be applied to the pushover analysis data to yield a better outcome with respect to the NDA. At the end, the pacific earthquake engineering research (PEER) center methodology is utilized to generate the fragility curves using the properties obtained from PSDM plots and considering various states of damage ranging from minor to severe. The extended pile shaft shows more vulnerability with a higher probability with respect to minor damage compared to severe damage.

  17. Ball Lens Fiber Optic Sensor based Smart Handheld Microsurgical Instrument.

    PubMed

    Song, Cheol; Gehlbach, Peter L; Kang, Jin U

    2013-03-20

    During freehand performance of vitreoretinal microsurgery the surgeon must perform precise and stable maneuvers that achieve surgical objectives and avoid surgical risk. Here, we present an improved smart handheld microsurgical tool which is based on a ball lens fiber optic sensor that utilizes common path swept source optical coherence tomography. Improvements include incorporation of a ball lens single mode fiber optic probe that increases the working angle of the tool to greater than 45 degrees; and increases the magnitude of the distance sensing signal through water. Also presented is a cutting function with an improved ergonomic design. PMID:24224076

  18. Ball Lens Fiber Optic Sensor based Smart Handheld Microsurgical Instrument

    PubMed Central

    Song, Cheol; Gehlbach, Peter L.; Kang, Jin U.

    2013-01-01

    During freehand performance of vitreoretinal microsurgery the surgeon must perform precise and stable maneuvers that achieve surgical objectives and avoid surgical risk. Here, we present an improved smart handheld microsurgical tool which is based on a ball lens fiber optic sensor that utilizes common path swept source optical coherence tomography. Improvements include incorporation of a ball lens single mode fiber optic probe that increases the working angle of the tool to greater than 45 degrees; and increases the magnitude of the distance sensing signal through water. Also presented is a cutting function with an improved ergonomic design. PMID:24224076

  19. ECCD performance analysis of future KSTAR ECH systems for extended applications

    NASA Astrophysics Data System (ADS)

    Sahu, B. B.; Bae, Y. S.; Jeong, J. H.; Joung, M.; Kwak, J. G.; Han, W. S.; Rhee, I.

    2014-10-01

    The ability of the KSTAR 170 GHz electron cyclotron (EC) wave launcher to drive a localized current is analyzed by means of the TORAY-GA ray-tracing code looking at extended physics application of the EC current drive (CD) in the KSTAR. Computation reveals that the EC-driven CD performance ( J CD), as compared to the plasma's boot-strap current ( J BS), i.e., the ratio J CD/ J BS, for the normalized minor radius, ρ > 0.5, is not good for the current design of the 1-MW 170-GHz launcher. Calculations at a lower frequency of 105 GHz have shown improved values for the J CD. Depending upon the launcher port's availability, computations are carried out to find the pivot position for future proposed launchers by optimizing the figures of merit at respective locations. These computations show that Z = +30 cm gives the maximum figure of merit. Computations also show a possible synergy between the two launchers, one pivoted at Z = +30 cm and the other at Z = -25.2 cm. The main aim of this study is to provide guidance for the design of both launchers in order to optimize their performance according to the physics application.

  20. Post-sleep inertia performance benefits of longer naps in simulated nightwork and extended operations.

    PubMed

    Mulrine, Hannah M; Signal, T Leigh; van den Berg, Margo J; Gander, Philippa H

    2012-11-01

    Operational settings involving shiftwork or extended operations require periods of prolonged wakefulness, which in conjunction with sleep loss and circadian factors, can have a negative impact on performance, alertness, and workplace safety. Napping has been shown to improve performance and alertness after periods of prolonged wakefulness and sleep loss. Longer naps may not only result in longer-lasting benefits but also increase the risk of sleep inertia immediately upon waking. The time course of performance after naps of differing durations is thus an important consideration in weighing the benefits and risks of napping in workplace settings. The objective of this study was to evaluate the effectiveness of nap opportunities of 20, 40, or 60 min for maintaining alertness and performance 1.5-6 h post-nap in simulated nightwork (P1) or extended operations (P2). Each protocol included 12 participants in a within-subjects design in a controlled laboratory environment. After a baseline 8 h time-in-bed, healthy young males (P1 mean age 25.1 yr; P2 mean age 23.2 yr) underwent either ≈ 20 h (P1) or ≈ 30 h (P2) of sleep deprivation on four separate occasions, followed by nap opportunities of 0, 20, 40, and 60 min. Sleep on the baseline night and during the naps was recorded polysomnographically. During the nap opportunities, sleep onset latency was short and sleep efficiency was high. A greater proportion of slow-wave sleep (SWS) was obtained in nap opportunities of 40 and 60 min compared with 20 min. Rapid eye movement (REM) sleep occurred infrequently. A subjective sleepiness rating (Karolinska Sleepiness Scale, KSS), 2-Back Working Memory Task (WMT), and Psychomotor Vigilance Task (PVT) were completed 1.5, 2, 2.5, 3, 4, 5, and 6 h post-nap. The slowest 10% of PVT responses were significantly faster after 40 and 60 min naps compared with a 20 min (P1) or no (P2) nap. There were significantly fewer PVT lapses after 40 and 60 min naps compared with no nap (P2), and

  1. Handheld computers in medicine: the way forward.

    PubMed

    Horsley, A; Forster, L

    2005-07-01

    Handheld computers are now a common sight in medicine, but there are scarce data on who actually uses them and what functions are found to be most useful. This is the first study of handheld computer use in a British hospital, and shows that there is already considerable use and acceptance of the technology, with 22 of 55 (40%) physicians possessing and using such a device. Doctors in training grades are more likely to make use of medical software, particularly textbooks, calculators, and formularies. The main barriers to greater use of this technology were cost of software and poor applicability to UK practice. PMID:15998828

  2. Hand-held multiple system gas chromatograph

    DOEpatents

    Yu, Conrad M.

    2001-01-01

    A multiple parallel hand-held gas chromatograph (GC) system which includes several independent GCs. Each independent GC has its own injector, separation column, detector and oven and the GCs are mounted in a light weight hand-held assembly. Each GC operates independently and simultaneously. Because of different coatings in different separation columns, different retention times for the same gas will be measured. Thus, for a GC system with multiple parallel GCs, the system can measure, in a short period, different retention times and provide a cross-reference in the determination of the measured gas and to become a two-dimensional system for direct field use.

  3. Advances in handheld FT-IR instrumentation

    NASA Astrophysics Data System (ADS)

    Arnó, Josep; Cardillo, Len; Judge, Kevin; Frayer, Maxim; Frunzi, Michael; Hetherington, Paul; Levy, Dustin; Oberndorfer, Kyle; Perec, Walter; Sauer, Terry; Stein, John; Zuidema, Eric

    2012-06-01

    FT-IR spectroscopy is the technology of choice to identify solid and liquid phase unknown samples. The challenges of ConOps (Concepts of Operation) in emergency response and military field applications require a significant redesign of the stationary FT-IR bench-top instruments typically used in laboratories. Specifically, field portable units require high levels of resistance against mechanical shock and chemical attack, ease of use in restrictive gear, quick and easy interpretation of results, and reduced size. In the last 20 years, FT-IR instruments have been re-engineered to fit in small suitcases for field portable use and recently further miniaturized for handheld operation. This article introduces the advances resulting from a project designed to overcome the challenges associated with miniaturizing FT-IR instruments. The project team developed a disturbance-corrected permanently aligned cube corner interferometer for improved robustness and optimized opto-mechanical design to maximize optical throughput and signal-to-noise ratios. Thermal management and heat flow were thoroughly modeled and studied to isolate sensitive components from heat sources and provide the widest temperature operation range. Similarly, extensive research on mechanical designs and compensation techniques to protect against shock and vibration will be discussed. A user interface was carefully created for military and emergency response applications to provide actionable information in a visual, intuitive format. Similar to the HazMatID family of products, state-of-the-art algorithms were used to quickly identify the chemical composition of complex samples based on the spectral information. This article includes an overview of the design considerations, tests results, and performance validation of the mechanical ruggedness, spectral, and thermal performance.

  4. 30 CFR 57.14116 - Hand-held power tools.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held power tools. 57.14116 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  5. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  6. 30 CFR 57.14116 - Hand-held power tools.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand-held power tools. 57.14116 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  7. 30 CFR 56.14116 - Hand-held power tools.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand-held power tools. 56.14116 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  8. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  9. 30 CFR 57.12033 - Hand-held electric tools.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held electric tools. 57.12033 Section 57.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12033 Hand-held electric tools. Hand-held electric tools shall not...

  10. 30 CFR 57.12033 - Hand-held electric tools.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held electric tools. 57.12033 Section 57.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12033 Hand-held electric tools. Hand-held electric tools shall not...

  11. 30 CFR 57.14116 - Hand-held power tools.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand-held power tools. 57.14116 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  12. 30 CFR 56.14116 - Hand-held power tools.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held power tools. 56.14116 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  13. 30 CFR 56.14116 - Hand-held power tools.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held power tools. 56.14116 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  14. 30 CFR 57.12033 - Hand-held electric tools.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held electric tools. 57.12033 Section 57.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12033 Hand-held electric tools. Hand-held electric tools shall not...

  15. 30 CFR 57.12033 - Hand-held electric tools.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand-held electric tools. 57.12033 Section 57.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12033 Hand-held electric tools. Hand-held electric tools shall not...

  16. 30 CFR 57.12033 - Hand-held electric tools.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand-held electric tools. 57.12033 Section 57.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Surface and Underground § 57.12033 Hand-held electric tools. Hand-held electric tools shall not...

  17. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  18. 30 CFR 57.14116 - Hand-held power tools.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held power tools. 57.14116 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  19. 30 CFR 57.14116 - Hand-held power tools.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held power tools. 57.14116 Section 57... Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  20. 30 CFR 56.14116 - Hand-held power tools.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand-held power tools. 56.14116 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  1. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  2. 30 CFR 56.14116 - Hand-held power tools.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held power tools. 56.14116 Section 56... Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills, disc sanders, grinders and circular and chain saws, when used in the hand-held mode shall be...

  3. 30 CFR 56.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving hand-held drills. 56.7053 Section 56.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from...

  4. Objective 1: Extend Life, Improve Performance, and Maintain Safety of the Current Fleet Implementation Plan

    SciTech Connect

    Robert Youngblood

    2011-02-01

    Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. By the year 2030, domestic demand for electrical energy is expected to grow to levels of 16 to 36% higher than 2007 levels. At the same time, most currently operating nuclear power plants will begin reaching the end of their 60 year operating licenses. Figure E 1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development (R&D) Roadmap has organized its activities in accordance with four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document describes how Objective 1 and the LWRS Program will be implemented. The existing U.S. nuclear fleet has a remarkable safety and performance record and today accounts for 70% of the low greenhouse

  5. Objective 1: Extend Life, Improve Performance, and Maintain Safety of the Current Fleet Implementation Plan

    SciTech Connect

    Robert Youngblood

    2011-01-01

    Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. By the year 2030, domestic demand for electrical energy is expected to grow to levels of 16 to 36% higher than 2007 levels. At the same time, most currently operating nuclear power plants will begin reaching the end of their 60 year operating licenses. Figure E 1 shows projected nuclear energy contribution to the domestic generating capacity. If current operating nuclear power plants do not operate beyond 60 years, the total fraction of generated electrical energy from nuclear power will begin to decline—even with the expected addition of new nuclear generating capacity. The oldest commercial plants in the United States reached their 40th anniversary in 2009. The U.S. Department of Energy Office of Nuclear Energy’s Research and Development (R&D) Roadmap has organized its activities in accordance with four objectives that ensure nuclear energy remains a compelling and viable energy option for the United States. The objectives are as follows: (1) develop technologies and other solutions that can improve the reliability, sustain the safety, and extend the life of the current reactors; (2) develop improvements in the affordability of new reactors to enable nuclear energy to help meet the Administration’s energy security and climate change goals; (3) develop sustainable nuclear fuel cycles; and (4) understand and minimize risks of nuclear proliferation and terrorism. The Light Water Reactor Sustainability (LWRS) Program is the primary programmatic activity that addresses Objective 1. This document describes how Objective 1 and the LWRS Program will be implemented. The existing U.S. nuclear fleet has a remarkable safety and performance record and today accounts for 70% of the low greenhouse

  6. Three-dimensional in vivo imaging by a handheld dual-axes confocal microscope

    PubMed Central

    Ra, Hyejun; Piyawattanametha, Wibool; Mandella, Michael J.; Hsiung, Pei-Lin; Hardy, Jonathan; Wang, Thomas D.; Contag, Christopher H.; Kino, Gordon S.; Solgaard, Olav

    2008-01-01

    We present a handheld dual-axes confocal microscope that is based on a two-dimensional microelectromechanical systems (MEMS) scanner. It performs reflectance and fluorescence imaging at 488 nm wavelength, with three-dimensional imaging capability. The fully packaged microscope has a diameter of 10 mm and acquires images at 4 Hz frame rate with a maximum field of view of 400 μm × 260 μm. The transverse and axial resolutions of the handheld probe are 1.7 μm and 5.8 μm, respectively. Capability to perform real time small animal imaging is demonstrated in vivo in transgenic mice. PMID:18545427

  7. Development of dual sensor hand-held detector

    NASA Astrophysics Data System (ADS)

    Sezgin, Mehmet

    2010-04-01

    In this paper hand-held dual sensor detector development requirements are considered dedicated to buried object detection. Design characteristics of such a system are categorized and listed. Hardware and software structures, ergonomics, user interface, environmental and EMC/EMI tests to be applied and performance test issues are studied. Main properties of the developed system (SEZER) are presented, which contains Metal Detector (MD) and Ground Penetrating Radar (GPR). The realized system has ergonomic structure and can detect both metallic and non-metallic buried objects. Moreover classification of target is possible if it was defined to the signal processing software in learning phase.

  8. Performance Enhancement of Pharmacokinetic Diffuse Fluorescence Tomography by Use of Adaptive Extended Kalman Filtering.

    PubMed

    Wang, Xin; Wu, Linhui; Yi, Xi; Zhang, Yanqi; Zhang, Limin; Zhao, Huijuan; Gao, Feng

    2015-01-01

    Due to both the physiological and morphological differences in the vascularization between healthy and diseased tissues, pharmacokinetic diffuse fluorescence tomography (DFT) can provide contrast-enhanced and comprehensive information for tumor diagnosis and staging. In this regime, the extended Kalman filtering (EKF) based method shows numerous advantages including accurate modeling, online estimation of multiparameters, and universal applicability to any optical fluorophore. Nevertheless the performance of the conventional EKF highly hinges on the exact and inaccessible prior knowledge about the initial values. To address the above issues, an adaptive-EKF scheme is proposed based on a two-compartmental model for the enhancement, which utilizes a variable forgetting-factor to compensate the inaccuracy of the initial states and emphasize the effect of the current data. It is demonstrated using two-dimensional simulative investigations on a circular domain that the proposed adaptive-EKF can obtain preferable estimation of the pharmacokinetic-rates to the conventional-EKF and the enhanced-EKF in terms of quantitativeness, noise robustness, and initialization independence. Further three-dimensional numerical experiments on a digital mouse model validate the efficacy of the method as applied in realistic biological systems. PMID:26089975

  9. Circadian Entrainment, Sleep-Wake Regulation and Neurobehavioral Performance During Extended Duration Space Flight

    NASA Technical Reports Server (NTRS)

    Czeisler, Charles A.

    1999-01-01

    Long-duration manned space flight requires crew members to maintain a high level of cognitive performance and vigilance while operating and monitoring sophisticated instrumentation. However, the reduction in the strength of environmental synchronizers in the space environment leads to misalignment of circadian phase among crew members, coupled with restricted time available to sleep, results in sleep deprivation and consequent deterioration of neurobehavioral function. Crew members are provided, and presently use, long-acting benzodiazepine hypnotics on board the current, relatively brief space shuttle missions to counteract such sleep disruption, a situation that is only likely to worsen during extended duration missions. Given the known carry-over effects of such compounds on daytime performance, together with the reduction in emergency readiness associated with their use at night, NASA has recognized the need to develop effective but safe countermeasures to allow crew members to obtain an adequate amount of sleep. Over the past eight years, we have successfully implemented a new technology for shuttle crew members involving bright light exposure during the pre-launch period to facilitate adaptation of the circadian timing system to the inversions of the sleep-wake schedule often required during dual shift missions. However for long duration space station missions it will be necessary to develop effective and attainable countermeasures that can be used chronically to optimize circadian entrainment. Our current research effort is to study the effects of light-dark cycles with reduced zeitgeber strength, such as are anticipated during long-duration space flight, on the entrainment of the endogenous circadian timing system and to study the effects of a countermeasure that consists of scheduled brief exposures to bright light on the human circadian timing system. The proposed studies are designed to address the following Specific Aims: (1) test the hypothesis that

  10. [The design of handheld fast ECG detector].

    PubMed

    Shi, Bo; Zhang, Genxuan; Tsau, Young

    2013-03-01

    A new handheld fast ECG detector based on low gain amplifier, the high resolution analog to digital converter, the real-time digital filter, fast P-QRS-T wave detection and abstraction algorithm was designed. The results showed that the ECG detector can meet the requirements of fast detecting heart rate and ECG P-QRS-T waveforms. PMID:23777065

  11. Trajectories in Operating a Handheld Tool

    ERIC Educational Resources Information Center

    Heuer, Herbert; Sulzenbruck, Sandra

    2009-01-01

    The authors studied the trajectories of the hand and of the tip of a handheld sliding first-order lever in aiming movements. With this kind of tool, straight trajectories of the hand are generally associated with curved trajectories of the tip of the lever and vice versa. Trajectories of the tip of the lever exhibited smaller deviations from…

  12. Handheld spectrometers: the state of the art

    NASA Astrophysics Data System (ADS)

    Crocombe, Richard A.

    2013-05-01

    "Small" spectrometers fall into three broad classes: small versions of laboratory instruments, providing data, subsequently processed on a PC; dedicated analyzers, providing actionable information to an individual operator; and process analyzers, providing quantitative or semi-quantitative information to a process controller. The emphasis of this paper is on handheld dedicated analyzers. Many spectrometers have historically been large, possible fragile, expensive and complicated to use. The challenge over the last dozen years, as instruments have moved into the field, has been to make spectrometers smaller, affordable, rugged, easy-to-use, but most of all capable of delivering actionable results. Actionable results can dramatically improve the efficiency of a testing process and transform the way business is done. There are several keys to this handheld spectrometer revolution. Consumer electronics has given us powerful mobile platforms, compact batteries, clearly visible displays, new user interfaces, etc., while telecomm has revolutionized miniature optics, sources and detectors. While these technologies enable miniature spectrometers themselves, actionable information has demanded the development of rugged algorithms for material confirmation, unknown identification, mixture analysis and detection of suspicious materials in unknown matrices. These algorithms are far more sophisticated than the `correlation' or `dot-product' methods commonly used in benchtop instruments. Finally, continuing consumer electronics advances now enable many more technologies to be incorporated into handheld spectrometers, including Bluetooth, wireless, WiFi, GPS, cameras and bar code readers, and the continued size shrinkage of spectrometer `engines' leads to the prospect of dual technology or `hyphenated' handheld instruments.

  13. Handheld standoff mine detection system (HSTAMIDS) field evaluation in Namibia

    NASA Astrophysics Data System (ADS)

    Doheny, Robert C.; Burke, Sean; Cresci, Roger; Ngan, Peter; Walls, Richard; Chernoff, Jeff

    2006-05-01

    The Humanitarian Demining Research and Development Program of the US Army RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD), under the direction of the Office of Assistant Secretary of Defense for Special Operations and Low-Intensity Conflict (OASD SO/LIC) and with participation from the International Test and Evaluation Program (ITEP) for humanitarian demining, conducted an in-country field evaluation of the Handheld Standoff Mine Detection System (HSTAMIDS) in the southern African country of Namibia. Participants included the US Humanitarian Demining Team of NVESD; ITEP personnel from several member countries; deminers from two non-governmental organizations in Angola, Menschen Gegen Minen (MgM) and HALO Trust; and CyTerra Corporation. The primary objectives were to demonstrate the performance of the U.S. Army's newest handheld multisensor mine detector, the HSTAMIDS, to the performance of the metal detector being used by local demining organizations and also to assess the performance of deminers using the HSTAMIDS after limited experience and training.

  14. Center of percussion of hand-held implements

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2004-05-01

    The center of percussion is commonly regarded as a sweet spot when referring to a baseball bat or a tennis racquet because it is assumed that there will be no sudden motion of the handle with respect to the hand if the corresponding axis of rotation passes through the hand. A problem with this interpretation is that the hand extends over a finite length of the handle and exerts an opposing reaction force on the handle. The hand also changes the total mass and moment of inertia of the system, while the arm restricts free motion of the hand. Experimental results are presented showing that the axis of rotation passes through the hand or the wrist for all the usual impact points on a hand-held implement. As a result, the impact point that feels best is usually the node of the fundamental vibration mode, not the center of percussion.

  15. Use of the handheld programmable calculator in the preparation of TPN solutions.

    PubMed

    DiDonato, L J

    1983-10-01

    A handheld programmable calculator was used to increase speed and decrease errors when calculating and labeling total parenteral nutrition formulations for pediatric patients. A program was developed and tested and an evaluation of the calculator vs. the manual method was performed. The time required to calculate total parenteral nutrition formulations decreased 50% and errors decreased from 3% to 0. Use of a handheld programmable calculator saves time and increases the accuracy of calculations and labels when preparing total parenteral nutrition formulations. The approximate total cost of the calculator, printer, and card reader is $1000. PMID:10310318

  16. Design of a handheld optical coherence microscopy endoscope

    NASA Astrophysics Data System (ADS)

    Korde, Vrushali R.; Liebmann, Erica; Barton, Jennifer K.

    2009-02-01

    Optical Coherence Microscopy (OCM) combines coherence gating, high numerical aperture optics, and a fiber core pinhole to provide high axial and lateral resolution with relatively large depth of imaging. We present a handheld rigid OCM endoscope with a 6 mm diameter tip, 1 mm scan width, and 1 mm imaging depth. This probe will allow noninvasive imaging of fine structural detail in vivo. X-Y scanning is performed distally with mirrors mounted to micro galvonometer scanners incorporated into the endoscope handle. Two scanning doublet lenses relay the stop from the galvonometers to the afocal relay stop. The endoscope optical design consists of an afocal Hopkins relay lens system and a 0.4 NA objective. To allow focusing at various depths in the tissue, the endoscope housing is designed in two pieces screwed together with a fine pitch threads. A small rotation of the outer housing moves the lenses proximal and distal relative to the window, causing the focal location in the tissue to change. The space between the final objective lens and the window is filled with distilled water to avoid misalignment of the focus and coherence gate. A knife edge test was performed and the line spread function FWHM was measured to be 2.25 μm. The MTF has at least 0.3 contrast at a 5 μm line pair. This rigid handheld OCM endoscope will be useful for application ranging from minimally invasive surgical imaging to assessing dysplasia and sun damage in skin.

  17. Mass spectra of proteins and other biomolecules recorded using a handheld instrument

    NASA Astrophysics Data System (ADS)

    Janfelt, Christian; Talaty, Nari; Mulligan, Christopher C.; Keil, Adam; Ouyang, Zheng; Cooks, R. Graham

    2008-12-01

    Proteins (myoglobin and cytochrome C), peptides (bradykinin and melittin), alkaloids in complex plant materials, and mixtures of phospholipids from a bacterial extract all give characteristic electrospray mass spectra using a handheld tandem mass spectrometer, Mini 10. The mass/charge range of the 10 kg Mini 10 was extended to m/z 2000 using resonant ion ejection at low frequency allowing analysis of proteins with molecular weights up to 17,000 Da. Fragmentation of peptides and proteins was observed.

  18. Handheld multispectral dual-axis confocal microscope for cervical cancer screening

    NASA Astrophysics Data System (ADS)

    Sarapukdee, Pongsak; Rattanavarin, Santi; Jarujareet, Ungkarn; Khemthongcharoen, Numfon; Jolivot, Romuald; Jung, Il Woong; López, Daniel; Mandella, Michael J.; Piyawattanametha, Wibool

    2013-03-01

    Our work demonstrates a MEMS based handheld dual-axis confocal microscope for cervical cancer screening. Imaging demonstration is performed with plant and animal tissue biopsies. The data is collected and displayed in real time with 2-5 Hz frame rates.

  19. Microfluidic MEMS hand-held flow cytometer

    NASA Astrophysics Data System (ADS)

    Grafton, Meggie M. G.; Maleki, Teimour; Zordan, Michael D.; Reece, Lisa M.; Byrnes, Ron; Jones, Alan; Todd, Paul; Leary, James F.

    2011-02-01

    Due to a number of recent technological advances, a hand-held flow cytometer can be achieved by use of semiconductor illuminators, optical sensors (all battery powered) and sensitive cell markers such as immuno-quantum dot (Qdot) labels. The specific application described is of a handheld blood analyzer that can quickly process a drop of whole, unfractionated human peripheral blood by real-time, on-chip magnetic separation of white blood cells (WBCs) and red blood cells (RBCs) and further fluorescence analysis of Qdot labeled WBC subsets. Various microfluidic patterns were fabricated in PDMS and used to characterize flow of single cells and magnetic deflection of magnetically labeled cells. An LED excitation, avalanche photodiode detection system (SensL Technologies, Ltd., Cork, Ireland) was used for immuno-Qdot detection of WBC subsets. A static optical setup was used to determine the sensitivity of the detection system. In this work we demonstrate: valve-less, on-chip magnetic sorting of immunomagnetically labeled white blood cells, bright Qdot labeling of lymphocytes, and counting of labeled white blood cells. Comparisons of these results with conventional flow cytometric analyses are reported. Sample preparation efficiency was determined by labeling of isolated white blood cells. Appropriate flow rates were determined for optical detection and confirmed with flowing particles. Several enabling technologies required for a truly portable, battery powered, hand-held flow cytometer for use in future point-of-care diagnostic devices have been demonstrated. The combining of these technologies into an integrated handheld instrument is in progress and results on whole blood cell analysis are to be reported in another paper.

  20. A Proposal for Job Descriptions and Performance Standards for Webster University Extended Campus Support Staff.

    ERIC Educational Resources Information Center

    King, John R., III

    A survey was conducted of all Webster University (Missouri) Extended Campus site directors (N=37) addressing the duties they associated with support staff positions at their sites. The directors were asked to assign relative importance in the duty rankings they listed and to show the job titles used for the positions at their sites. The 16…

  1. The Impact of Extended Time on SAT® Test Performance. Research Report No. 2005-8. ETS RR-05-20

    ERIC Educational Resources Information Center

    Mandinach, Ellen B.; Bridgeman, Brent; Cahalan-Laitusis, Cara; Trapani, Catherine

    2005-01-01

    The effects of extended time on SAT Reasoning Test™ performance are examined. The study explored the impact of providing standard time, time and a half (1.5 time) with and without specified section breaks, and double time without specified section breaks on the verbal and mathematics sections of the SAT®. Differences among ability, disability, and…

  2. Leadership Practices that Contribute to Extended Presidential Tenure and the Development of High-Performing Community Colleges

    ERIC Educational Resources Information Center

    Poole, David

    2012-01-01

    The purpose of this mixed methods study was to identify and better understand leadership styles and practices that contribute to extended presidential tenure and the development of high-performing community colleges. Profiles were developed drawing from the six California community college chancellors, presidents, and superintendent/presidents who…

  3. Micron: an Actively Stabilized Handheld Tool for Microsurgery

    PubMed Central

    MacLachlan, Robert A.; Becker, Brian C.; Tabarés, Jaime Cuevas; Podnar, Gregg W.; Lobes, Louis A.; Riviere, Cameron N.

    2011-01-01

    We describe the design and performance of a hand-held actively stabilized tool to increase accuracy in micro-surgery or other precision manipulation. It removes involuntary motion such as tremor by actuating the tip to counteract the effect of the undesired handle motion. The key components are a three-degree-of-freedom piezoelectric manipulator that has 400 μm range of motion, 1 N force capability, and bandwidth over 100 Hz, and an optical position measurement subsystem that acquires the tool pose with 4 μm resolution at 2000 samples/s. A control system using these components attenuates hand motion by at least 15 dB (a fivefold reduction). By considering the effect of the frequency response of Micron on the human visual feedback loop, we have developed a filter that reduces unintentional motion, yet preserves intuitive eye-hand coordination. We evaluated the effectiveness of Micron by measuring the accuracy of the human/machine system in three simple manipulation tasks. Handheld testing by three eye surgeons and three non-surgeons showed a reduction in position error of between 32% and 52%, depending on the error metric. PMID:23028266

  4. Military GPS handheld display development: past, present, and future

    NASA Astrophysics Data System (ADS)

    Shiel, Alicia P.; Smothers, Andrew D.

    1998-09-01

    The military Precision Lightweight Global Positioning System (GPS) Receiver or 'PLGR' hand-held product eliminated many technical barriers to bring a low cost 'commercial' transflective display to be a standard military issue. This low cost display, combined with silicone keypad, provides a human interface that has been extremely successful at a current rate of 190 units built per day. With the PLGR and more recent PLGR-II success in meeting the challenges of the military GPS market with a low-cost display, the PLGR is now a platform to provide affordable military-commercial display solutions for the future. The paper will provide technical background on the display provided for the initial GPS hand- held award and the technology changes that were based on the voice of the customer. The display performance in the areas of contrast, Night Vision Goggle (NVG) compatibility, backlighting, and off axis viewability will be presented. Current and future challenges in hand-held and vehicular GPS products will also be presented with possible applications of new display technologies.

  5. A hand-held EPR scanner for transcutaneous oximetry

    NASA Astrophysics Data System (ADS)

    Wolfson, Helen; Ahmad, Rizwan; Twig, Ygal; Blank, Aharon; Kuppusamy, Periannan

    2015-03-01

    Cutaneous (skin) oxygenation is an important prognostic factor for the treatment of chronic wounds, skin cancer, diabetes side effects, and limb amputation. Currently, there are no reliable methods for measuring this parameter. Oximetry, using electron paramagnetic resonance (EPR) spectroscopy, is emerging as a potential tool for clinical oximetry, including cutaneous applications. The problem with EPR oximetry, however, is that the conventional EPR design requires the use of a large magnet that can generate homogeneous field across the sample, making it unattractive for clinical practice. We present a novel approach that makes use of a miniature permanent magnet, combined with a small microwave resonator, to enable the acquisition of EPR signals from paramagnetic species placed on the skin. The instrumentation consists of a hand-held, modular, cylindrical probehead with overall dimensions of 36-mm diameter and 24-mm height, with 150-g weight. The probehead includes a Halbach array of 16 pieces (4×4×8 mm3) of Sm-Co permanent magnet and a loop-gap resonator (2.24 GHz). Preliminary measurements using a Hahn-echo pulse sequence (800 echos in 20 ms) showed a signalto- noise ratio of ~70 compared to ~435 in a homogenous magnet under identical settings. Further work is in progress to improve the performance of the probehead and to optimize the hand-held system for clinical use

  6. Semiautomated Intraocular Laser Surgery using Handheld Instruments

    PubMed Central

    Becker, Brian C.; MacLachlan, Robert A.; Lobes, Louis A.; Riviere, Cameron N.

    2011-01-01

    Background and Objective In laser retinal photocoagulation, hundreds of dot-like burns are applied. We introduce a robot-assisted technique to enhance the accuracy and reduce the tedium of the procedure. Materials and Methods Laser burn locations are overlaid on preoperative retinal images using common patterns such as grids. A stereo camera/monitor setup registers and displays the planned burn locations overlaid on real-time video. Using an active handheld micromanipulator, a 7×7 grid of burns spaced 650 μm apart is applied to both paper slides and porcine retina in vitro using 30 ms laser pulses at 532 nm. Two scenarios were tested: unaided, in which the micromanipulator is inert and the laser fires at a fixed frequency, and aided, in which the micromanipulator actively targets burn locations and the laser fires automatically upon target acquisition. Error is defined as the distance from the center of the observed burn mark to the preoperatively selected target location. Results An experienced retinal surgeon performed trials with and without robotic assistance, on both paper slides and porcine retina in vitro. In the paper slide experiments at an unaided laser repeat rate of 0.5 Hz, error was 125±62 μm with robotic assistance and 149±76 μm without (p < 0.005), and trial duration was 70±8 s with robotic assistance and 97±7 s without (p < 0.005). At a repeat rate of 1.0 Hz, error was 129±69 μm with robotic assistance and 166±91 μm without (p < 0.005), and trial duration was 26±4 s with robotic assistance and 47±1 s without (p < 0.005). At a repeat rate of 2.0 Hz on porcine retinal tissue, error was 123±69 μm with robotic assistance and 203±104 μm without (p < 0.005). Conclusion Robotic assistance can increase the accuracy of laser photocoagulation while reducing the duration of the operation. PMID:20333740

  7. Power and entropy generation of an extended irreversible Brayton cycle: optimal parameters and performance

    NASA Astrophysics Data System (ADS)

    Herrera, Carlos A.; Sandoval, Jairo A.; Rosillo, Miguel E.

    2006-08-01

    Finite time thermodynamics is used to solve a new model of an extended Brayton cycle with variable-temperature heat reservoirs and finite size heat exchangers. The model takes into account external and internal entropy generation and handles heat recovery and heat leaks to the environment in a novel way. The extended system considerations are very important for minimizing entropy generation and maximizing second law efficiency, profit and ecological criterion. An optimization analysis was developed on this new model to determine its maximum power and minimum entropy generation, and amid the most important findings were the global maximum net power, global minimum entropy generation, optimum global heat exchangers size distribution, best working fluid specific heat ratio and optimal fluid heat capacities, some of these never having been published previously.

  8. Handheld Micromanipulation with Vision-Based Virtual Fixtures

    PubMed Central

    Becker, Brian C.; MacLachlan, Robert A.; Hager, Gregory D.; Riviere, Cameron N.

    2011-01-01

    Precise movement during micromanipulation becomes difficult in submillimeter workspaces, largely due to the destabilizing influence of tremor. Robotic aid combined with filtering techniques that suppress tremor frequency bands increases performance; however, if knowledge of the operator's goals is available, virtual fixtures have been shown to greatly improve micromanipulator precision. In this paper, we derive a control law for position-based virtual fixtures within the framework of an active handheld micromanipulator, where the fixtures are generated in real-time from microscope video. Additionally, we develop motion scaling behavior centered on virtual fixtures as a simple and direct extension to our formulation. We demonstrate that hard and soft (motion-scaled) virtual fixtures outperform state-of-the-art tremor cancellation performance on a set of artificial but medically relevant tasks: holding, move-and-hold, curve tracing, and volume restriction. PMID:23275860

  9. Physician order entry of ultrasound examination with handheld wireless terminal

    NASA Astrophysics Data System (ADS)

    Matsuya, Shiro; Onogi, Yuzo; Shinohara, Nobuo; Yamaguchi, Izumi; Watanabe, Hiroki; Ohe, Kazuhiko; Yamaguchi, Kenichi; Niidome, Takuro; Oyama, Hiroshi

    2004-04-01

    Although our hospital has an electronic order entry system, physician order entries must be performed using one of a limited number of terminals which are located in places like nurse stations. Due to this limitation, the mobility of the ultrasound machine cannot be fully exploited if a physician wants to perform a mobile ultrasound examination far from an entry terminal. In addition, this situation increases the possibility that a physician will fail to issue a paper voucher of the examination. In an attempt to resolve these problems, we have developed a mobile physician order entry system that incorporates ultrasound machines equipped with handheld wireless terminals, which use the 802.11b standard and the bandwidth is 11 Mbps. This is an efficient way to order ultrasound examination entries because physicians can register entries at any location in a hospital ward. In addition, the proposed system is a reliable method by which to attach images upon ultrasound examination entry.

  10. 76 FR 22918 - In the Matter of Certain Handheld Electronic Computing Devices, Related Software, and Components...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... COMMISSION In the Matter of Certain Handheld Electronic Computing Devices, Related Software, and Components... States after importation of certain handheld electronic computing devices, related software, and... importation of certain handheld electronic computing devices, related software, and components thereof...

  11. Risk based in vitro performance assessment of extended release abuse deterrent formulations.

    PubMed

    Xu, Xiaoming; Gupta, Abhay; Al-Ghabeish, Manar; Calderon, Silvia N; Khan, Mansoor A

    2016-03-16

    High strength extended release opioid products, which are indispensable tools in the management of pain, are associated with serious risks of unintentional and potentially fatal overdose, as well as of misuse and abuse that might lead to addiction. The issue of drug abuse becomes increasingly prominent when the dosage forms can be readily manipulated to release a high amount of opioid or to extract the drug in certain products or solvents. One approach to deter opioid drug abuse is by providing novel abuse deterrent formulations (ADF), with properties that may be viewed as barriers to abuse of the product. However, unlike regular extended release formulations, assessment of ADF technologies are challenging, in part due to the great variety of formulation designs available to achieve deterrence of abuse by oral, parenteral, nasal and respiratory routes. With limited prior history or literature information, and lack of compendial standards, evaluation and regulatory approval of these novel drug products become increasingly difficult. The present article describes a risk-based standardized in-vitro approach that can be utilized in general evaluation of abuse deterrent features for all ADF products. PMID:26784976

  12. Hand-held UXO Discriminator

    SciTech Connect

    Gasperikova, E.; Smith, J.T.; Kappler, K.N.; Ratti, A.; Morrison, H.F.; Becker, A.

    2010-04-01

    With prior funding (UX-1225, MM-0437, and MM-0838), we have successfully designed and built a cart-mounted Berkeley UXO Discriminator (BUD) and demonstrated its performance at various test sites (e.g., Gasperikova et al., 2007, 2009). It is a multi-transmitter multi-receiver active electromagnetic system that is able to discriminate UXO from scrap at a single measurement position, hence eliminates equirement of a very accurate sensor location. The cart-mounted system comprises of three orthogonal transmitters and eight pairs of differenced receivers (Smith et al., 2007). Receiver coils are located on ymmetry lines through the center of the system and see identical fields during the on-time of the pulse in all of the transmitter coils. They can then be wired in opposition to produce zero output during the n-ime of the pulses in three orthogonal transmitters. Moreover, this configuration dramatically reduces noise in the measurements by canceling the background electromagnetic fields (these fields are uniform ver the scale of the receiver array and are consequently nulled by the differencing operation), and by canceling the noise contributed by the tilt of the receivers in the Earth's magnetic field, and therefore reatly enhances receivers sensitivity to the gradients of the target.

  13. Effect of flow on the acoustic performance of extended reaction lined ducts

    NASA Technical Reports Server (NTRS)

    Hersh, A. S.; Walker, B.

    1983-01-01

    A model is developed for the effects of uniform and boundary-layer mean flow on the attenuation and propagation of harmonically excited sound waves in an extended reaction lined cylindrical duct. A duct geometry consisting of an annular outer region of bulk material surrounding an inner cylinder of air is utilized. A numerical solution is obtained for the coupled wave equations governing the motion of the sound in both the inner and annular regions. It is found that the numerically predicted attenuation and propagations constants are in excellent agreement with measured values using Kevlar as the liner material for plane-wave mode (O,O) excitation over a wide range of mean flows and sound frequency. The boundary-layer effects are determined to be unimportant, at least for plane-wave sound. In addition, numerical studies indicate small differences between the use of either the radial velocity or the radial displacement boundary conditions.

  14. Diagnostic Capability of Comprehensive Handheld vs Transthoracic Echocardiography

    PubMed Central

    Cullen, Michael W.; Blauwet, Lori A.; Vatury, Ori M.; Mulvagh, Sharon L.; Behrenbeck, Thomas R.; Scott, Christopher G.; Pellikka, Patricia A.

    2014-01-01

    Objective To assess the diagnostic capability of handheld echocardiography (HHE) compared with transthoracic echocardiography (TTE) performed and evaluated by experienced sonographers and expert echocardiographers. Patients and Methods We conducted a prospective study of adult outpatients undergoing comprehensive TTE from July 9, 2012, through April 3, 2013. Experienced sonographers performed a detailed, standardized examination with a handheld ultrasound device (Vscan; GE Healthcare) that included 2-dimensional and color Doppler images from standard imaging windows. TTE and HHE images were independently interpreted by expert echocardiographers to whom the other study was masked. Agreement between the standard TTE and the HHE reports was analyzed. Results The study group contained 190 patients (mean [SD] age, 62 [17] years; 49% male). κ Values were 0.52 for left ventricular (LV) enlargement, 0.52 for right ventricular enlargement, 0.62 for regional wall motion abnormalities, 0.73 for aortic stenosis, and 0.61 for mitral regurgitation. Lin concordance correlation coefficients ranged from 0.89 for LV end-systolic diameter to 0.78 for LV end-diastolic diameter. In 51 patients (27%), echocardiographic findings were discordant between HHE and standard TTE. The most common discordant finding was the presence vs absence of any regional wall motion abnormalities. In discordant cases, HHE tended to underestimate, rather than overestimate, the severity of abnormal findings. Conclusion HHE in experienced hands shows moderate correlation with standard TTE, but discordant findings were present in 27% of patients. HHE, even when performed and interpreted by experienced operators, should not be used as a surrogate for standard TTE. PMID:24684783

  15. Handheld magnetic sensor for measurement of tension

    NASA Astrophysics Data System (ADS)

    Singal, K.; Rajamani, R.

    2012-04-01

    This letter develops an analytical formulation for measurement of tension in a string using a handheld sensor. By gently pushing the sensor against the string, the tension in the string can be obtained. An experimental sensor prototype is constructed to verify the analytical formulation. The centimeter-sized prototype utilizes three moving pistons and magnetic field based measurements of their positions. Experimental data show that the sensor can accurately measure tension on a bench top rig. The developed sensor could be useful in a variety of orthopedic surgical procedures, including knee replacement, hip replacement, ligament repair, shoulder stabilization, and tendon repair.

  16. Hand-held and automated breast ultrasound

    SciTech Connect

    Bassett, L.W.; Gold, R.H.; Kimme-Smith, C.

    1985-01-01

    The book is a guide for physicians and technologists who use US as an adjunct to mammography; it carefully outlines the pros and cons of US of the breast and its role in the diagnosis of benign and malignant diseases. After an introduction that discusses the philosophy of breast US, the chapters cover the physics of US and instrumentation (both hand-held transducers as well as automated water path scanners), then proceed to a discussion of the normal breast. Sections on benign disorders, malignant lesions, and pitfalls of diagnosis are followed by quiz cases.

  17. Performance, durability and low temperature evaluation of sunflower oil as a diesel fuel extender

    SciTech Connect

    Baranescu, R.A.; Lusco, J.J.

    1982-01-01

    The paper presents the results of a research project to evaluate performance and durability of direct injection turbocharged diesel engines using sunflower oil and blends thereof. Alcaline refined sunflower oil and three different blends of sunflower oil and diesel fuel were comparatively tested against No. 2 diesel fuel for: physical and chemical characteristics, fuel injection system performance, short term engine performance, propensity to nozzle deposits buildup, limited durability operation and low temperature starting capability. Results are presented for the various phases of the project and correlations between the fuel characteristics and engine accept-ability are discussed. 19 figures, 2 tables.

  18. Extended performance electric propulsion power processor design study. Volume 2: Technical summary

    NASA Technical Reports Server (NTRS)

    Biess, J. J.; Inouye, L. Y.; Schoenfeld, A. D.

    1977-01-01

    Electric propulsion power processor technology has processed during the past decade to the point that it is considered ready for application. Several power processor design concepts were evaluated and compared. Emphasis was placed on a 30 cm ion thruster power processor with a beam power rating supply of 2.2KW to 10KW for the main propulsion power stage. Extension in power processor performance were defined and were designed in sufficient detail to determine efficiency, component weight, part count, reliability and thermal control. A detail design was performed on a microprocessor as the thyristor power processor controller. A reliability analysis was performed to evaluate the effect of the control electronics redesign. Preliminary electrical design, mechanical design and thermal analysis were performed on a 6KW power transformer for the beam supply. Bi-Mod mechanical, structural and thermal control configurations were evaluated for the power processor and preliminary estimates of mechanical weight were determined.

  19. Measuring critical care air support teams' performance during extended periods of duty.

    PubMed

    Lamb, Di

    2010-01-01

    The Royal Air Force (RAF) Critical Care Air Support Teams (CCASTs) aeromedically evacuate seriously injured service personnel. Long casualty evacuation chains create logistical constraints that must be considered when aeromedically evacuating patients. One constraint is the length of a CCAST mission and its potential effect on team member performance. Despite no evidence of patient care compromise, the RAF has commissioned a study to investigate whether CCAST mission length influences performance. Describing and understanding the role of a CCAST enabled fatigue to be defined. Factors essential to studying fatigue were then identified that were used to develop a theoretical model for designing a study to measure the effects of fatigue on CCAST performance. Relevant factors include the patient's clinical condition, team members' cognition and vigilance levels, and the occupational aviation environment. Further factors influencing overall performance include the duration and complexity of patient interventions, mission length, circadian influences, and fatigue countermeasures. PMID:20683231

  20. Extended pressure range performance of Kaiser/Marquardt 490N thruster

    NASA Astrophysics Data System (ADS)

    Ellison, J. R.; Kreiner, K. B.

    1993-06-01

    The performance of INTELSAT VI Reboost Program Liquid Apogee Motor (LAM) is studied using both ground and flight testing results. Ground testing based on an INTELSAT VI qualification unit, S/N 002A, was performed at the Kaiser Marquardt facility in California in 1991. Data obtained from the F-603 flight show that the R4-D 490 N LAM is susceptible to a dynamic combustion instability mode, called chugging, when operated at a low inlet pressure with helium saturated propellants.

  1. Handheld multispectral fluorescence lifetime imaging system for in vivo applications.

    PubMed

    Cheng, Shuna; Cuenca, Rodrigo M; Liu, Boang; Malik, Bilal H; Jabbour, Joey M; Maitland, Kristen C; Wright, John; Cheng, Yi-Shing Lisa; Jo, Javier A

    2014-03-01

    There is an increasing interest in the application of fluorescence lifetime imaging (FLIM) for medical diagnosis. Central to the clinical translation of FLIM technology is the development of compact and high-speed clinically compatible systems. We present a handheld probe design consisting of a small maneuverable box fitted with a rigid endoscope, capable of continuous lifetime imaging at multiple emission bands simultaneously. The system was characterized using standard fluorescent dyes. The performance was then further demonstrated by imaging a hamster cheek pouch in vivo, and oral mucosa tissue both ex vivo and in vivo, all using safe and permissible exposure levels. Such a design can greatly facilitate the evaluation of FLIM for oral cancer imaging in vivo. PMID:24688824

  2. Toward Standard Usability Questionnaires for Handheld Augmented Reality.

    PubMed

    Santos, Marc Ericson C; Polvi, Jarkko; Taketomi, Takafumi; Yamamoto, Goshiro; Sandor, Christian; Kato, Hirokazu

    2015-01-01

    Usability evaluations are important to improving handheld augmented reality (HAR) systems. However, no standard questionnaire considers perceptual and ergonomic issues found in HAR. The authors performed a systematic literature review to enumerate these issues. Based on these issues, they created a HAR usability scale that consists of comprehensibility and manipulability scales. These scales measure general system usability, ease of understanding the information presented, and ease of handling the device. The questionnaires' validity and reliability were evaluated in four experiments, and the results show that the questionnaires consistently correlate with other subjective and objective measures of usability. The questionnaires also have good reliability based on the Cronbach's alpha. Researchers and professionals can directly use these questionnaires to evaluate their own HAR applications or modify them with the insights presented in this article. PMID:26416363

  3. Design and Analysis of 6 DOF Handheld Micromanipulator.

    PubMed

    Yang, Sungwook; Maclachlan, Robert A; Riviere, Cameron N

    2012-12-31

    This paper presents the design and analysis of a handheld manipulator for vitreoretinal microsurgery and other biomedical applications. The design involves a parallel micromanipulator utilizing six piezoelectric linear actuators, combining compactness with a large range of motion and relatively high stiffness. Given the available force of the actuators, the overall dimension of the micromanipulator was optimized considering realistic external loads on a remote center of motion representing the point of expected contact with the sclera of the eye during microsurgery. Based on optimization and workspace analysis, a benchtop version of the micromanipulator was built with a base diameter of 25 mm and a height of 50 mm. It provides a hemispherical workspace of 4.0 mm diameter at the tool tip. The manipulation performance of the constructed manipulator was measured under a lateral load applied at the remote center of motion. The micromanipulator tolerated side loads up to 200 mN. PMID:24649394

  4. A Smart Haptic Hand-Held Device for Neurosurgical Microdissection.

    PubMed

    Payne, Christopher J; Marcus, Hani J; Yang, Guang-Zhong

    2015-09-01

    Microneurosurgery requires dexterity, precision and delicate force application in order to be carried out safely and effectively. Neurosurgeons must apply sufficient force in order to carry out microsurgical procedures effectively but not excessive force such that iatrogenic injury occurs. This paper presents a smart hand-held microsurgical instrument that indicates to the surgeon when a force-threshold has been exceeded by providing vibrotactile feedback. Many existing haptic-feedback systems, particularly master-slave robotic platforms, are large, highly complex, and costly. By comparison, the proposed device is compact, fail-safe and low cost. Two psychophysical user studies were carried out to assess the proposed vibrotactile force-threshold feedback system. A cadaveric pilot study was carried out to evaluate the device in a microdissection task. In all the studies performed, the haptic dissector device has shown to be effective in providing real-time feedback in terms of force application during microsurgical tasks. PMID:25631207

  5. Comparative Geometrical Investigations of Hand-Held Scanning Systems

    NASA Astrophysics Data System (ADS)

    Kersten, T. P.; Przybilla, H.-J.; Lindstaedt, M.; Tschirschwitz, F.; Misgaiski-Hass, M.

    2016-06-01

    An increasing number of hand-held scanning systems by different manufacturers are becoming available on the market. However, their geometrical performance is little-known to many users. Therefore the Laboratory for Photogrammetry & Laser Scanning of the HafenCity University Hamburg has carried out geometrical accuracy tests with the following systems in co-operation with the Bochum University of Applied Sciences (Laboratory for Photogrammetry) as well as the Humboldt University in Berlin (Institute for Computer Science): DOTProduct DPI-7, Artec Spider, Mantis Vision F5 SR, Kinect v1 + v2, Structure Sensor and Google's Project Tango. In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data were acquired by measurement with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M). The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

  6. Self-contained, hand-held optical spectrometer

    SciTech Connect

    Baird, W.; Nogar, N.S.

    1994-12-31

    The authors describe the design(s) and performance of a self-contained, portable (hand-held) optical spectrometer. The current instrument is based on a miniaturized monochromator, diode array detector, Peltier cooler and microprocessor control. It can be used either in absorption mode, or in a fluorescence-excitation mode (using an on-board UV penlamp). The unit contains an on-board computer, control pad and LCD display, and can write data to a demountable data key. On-board batteries allow operation for up to three hours in data acquisition mode, or up to twenty-four hours in stand-by mode. The instrument may couple to the sample either fiber-optically, or directly with a light-tight coupling unit. The authors also describe second generation instruments incorporating monolithic optical devices and/or interference filters. In general, these instruments can be made more compact, but at some cost in versatility and information content.

  7. Evaluation of a Handheld Data Collection Interface for Science Learning

    ERIC Educational Resources Information Center

    Parr, Cynthia Sims; Jones, Tricia; Songer, Nancy Butler

    2004-01-01

    Despite a rise in the use of handheld computers in classrooms, meaningful learning with personal digital assistant (PDA) technology remains poorly studied. This article reports results from an evaluation of customized handheld data collection software, the BioKIDS Sequence, which was used during an 8-week biodiversity curriculum unit by 5th and…

  8. A Cognitive Style Perspective to Handheld Devices: Customization vs. Personalization

    ERIC Educational Resources Information Center

    Hsieh, Chen-Wei; Chen, Sherry Y.

    2016-01-01

    Handheld devices are widely applied to support open and distributed learning, where students are diverse. On the other hand, customization and personalization can be applied to accommodate students' diversities. However, paucity of research compares the effects of customization and personalization in the context of handheld devices. To this end, a…

  9. Handheld Technology Acceptance in Radiologic Science Education and Training Programs

    ERIC Educational Resources Information Center

    Powers, Kevin Jay

    2012-01-01

    The purpose of this study was to explore the behavioral intention of directors of educational programs in the radiologic sciences to adopt handheld devices to aid in managing student clinical data. Handheld devices were described to participants as a technology representing a class of mobile electronic devices including, but not limited to,…

  10. Code Talk: Student Discourse and Participation with Networked Handhelds

    ERIC Educational Resources Information Center

    White, Tobin

    2006-01-01

    This study explores the potential of networked handheld computers to support collaborative problem solving in small groups. Drawing on data from a middle school mathematics classroom equipped with a wireless handheld network, I argue that the sharing of mathematical objects through interactive devices broadens the "bandwidth" of classroom…

  11. Learning Object Design Considerations for Small-Screen Handheld Devices

    ERIC Educational Resources Information Center

    Churchill, Daniel; Hedberg, John

    2008-01-01

    The key limitation of handheld technology for the delivery of learning objects is the small screen that is available for effective display. The smallness of the screen not only adversely affects the clarity, but it also negatively impacts on the acceptance and integration of this potentially useful technology in education. Handheld devices are…

  12. Educational Uses of Handheld Devices: What Are the Consequences?

    ERIC Educational Resources Information Center

    Song, Yanjie

    2007-01-01

    Handheld devices are being used increasingly in schools and higher education. Many researchers assume that the use of these devices will exert considerable impact on educational practices. However, to date, it appears that such use has not been sustainable and transferable. The impact of educational uses of handheld devices does not yet seem…

  13. 30 CFR 57.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving hand-held drills. 57.7053 Section 57.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Rotary Jet Piercing Drilling-Surface and Underground § 57.7053 Moving hand-held drills. Before...

  14. 30 CFR 57.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving hand-held drills. 57.7053 Section 57.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Rotary Jet Piercing Drilling-Surface and Underground § 57.7053 Moving hand-held drills. Before...

  15. 30 CFR 57.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving hand-held drills. 57.7053 Section 57.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Rotary Jet Piercing Drilling-Surface and Underground § 57.7053 Moving hand-held drills. Before...

  16. 30 CFR 57.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Moving hand-held drills. 57.7053 Section 57.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Rotary Jet Piercing Drilling-Surface and Underground § 57.7053 Moving hand-held drills. Before...

  17. 30 CFR 57.7053 - Moving hand-held drills.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving hand-held drills. 57.7053 Section 57.7053 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Rotary Jet Piercing Drilling-Surface and Underground § 57.7053 Moving hand-held drills. Before...

  18. A framework for performance measurement in university using extended network data envelopment analysis (DEA) structures

    NASA Astrophysics Data System (ADS)

    Kashim, Rosmaini; Kasim, Maznah Mat; Rahman, Rosshairy Abd

    2015-12-01

    Measuring university performance is essential for efficient allocation and utilization of educational resources. In most of the previous studies, performance measurement in universities emphasized the operational efficiency and resource utilization without investigating the university's ability to fulfill the needs of its stakeholders and society. Therefore, assessment of the performance of university should be separated into two stages namely efficiency and effectiveness. In conventional DEA analysis, a decision making unit (DMU) or in this context, a university is generally treated as a black-box which ignores the operation and interdependence of the internal processes. When this happens, the results obtained would be misleading. Thus, this paper suggest an alternative framework for measuring the overall performance of a university by incorporating both efficiency and effectiveness and applies network DEA model. The network DEA models are recommended because this approach takes into account the interrelationship between the processes of efficiency and effectiveness in the system. This framework also focuses on the university structure which is expanded from the hierarchical to form a series of horizontal relationship between subordinate units by assuming both intermediate unit and its subordinate units can generate output(s). Three conceptual models are proposed to evaluate the performance of a university. An efficiency model is developed at the first stage by using hierarchical network model. It is followed by an effectiveness model which take output(s) from the hierarchical structure at the first stage as a input(s) at the second stage. As a result, a new overall performance model is proposed by combining both efficiency and effectiveness models. Thus, once this overall model is realized and utilized, the university's top management can determine the overall performance of each unit more accurately and systematically. Besides that, the result from the network

  19. Infrared detection, recognition and identification of handheld objects

    NASA Astrophysics Data System (ADS)

    Adomeit, Uwe

    2012-10-01

    A main criterion for comparison and selection of thermal imagers for military applications is their nominal range performance. This nominal range performance is calculated for a defined task and standardized target and environmental conditions. The only standardization available to date is STANAG 4347. The target defined there is based on a main battle tank in front view. Because of modified military requirements, this target is no longer up-to-date. Today, different topics of interest are of interest, especially differentiation between friend and foe and identification of humans. There is no direct way to differentiate between friend and foe in asymmetric scenarios, but one clue can be that someone is carrying a weapon. This clue can be transformed in the observer tasks detection: a person is carrying or is not carrying an object, recognition: the object is a long / medium / short range weapon or civil equipment and identification: the object can be named (e. g. AK-47, M-4, G36, RPG7, Axe, Shovel etc.). These tasks can be assessed experimentally and from the results of such an assessment, a standard target for handheld objects may be derived. For a first assessment, a human carrying 13 different handheld objects in front of his chest was recorded at four different ranges with an IR-dual-band camera. From the recorded data, a perception experiment was prepared. It was conducted with 17 observers in a 13-alternative forced choice, unlimited observation time arrangement. The results of the test together with Minimum Temperature Difference Perceived measurements of the camera and temperature difference and critical dimension derived from the recorded imagery allowed defining a first standard target according to the above tasks. This standard target consist of 2.5 / 3.5 / 5 DRI line pairs on target, 0.24 m critical size and 1 K temperature difference. The values are preliminary and have to be refined in the future. Necessary are different aspect angles, different

  20. Thermal performance sensitivity studies in support of material modeling for extended storage of used nuclear fuel

    SciTech Connect

    Cuta, Judith M.; Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.

    2013-08-15

    The work reported here is an investigation of the sensitivity of component temperatures of a storage system, including fuel cladding temperatures, in response to age-related changes that could degrade the design-basis thermal behavior of the system. Three specific areas of interest were identified for this study. • degradation of the canister backfill gas from pure helium to a mixture of air and helium, resulting from postulated leakage due to stress corrosion cracking (SCC) of canister welds • changes in surface emissivity of system components, resulting from corrosion or other aging mechanisms, which could cause potentially significant changes in temperatures and temperature distributions, due to the effect on thermal radiation exchange between components • changes in fuel and basket temperatures due to changes in fuel assembly position within the basket cells in the canister The purpose of these sensitivity studies is to provide a realistic example of how changes in the physical properties or configuration of the storage system components can affect temperatures and temperature distributions. The magnitudes of these sensitivities can provide guidance for identifying appropriate modeling assumptions for thermal evaluations extending long term storage out beyond 50, 100, 200, and 300 years.

  1. Extended reach drilling advancements dramatically improve performance on Bass Strait wells

    SciTech Connect

    Santostefano, V.; Krepp, A.N.

    1994-12-31

    Esso Australia Ltd. (EAL) has been drilling deviated wells in Bass Strait since 1968. Recent technological developments have been employed on the Mackerel Infill Drilling Project, that have significantly improved EAL`s ability to drill Long Reach (LR)/Extended Reach (ER) wells more economically and consistently. The more notable achievements have been: advancements in hole condition reporting, utilizing torque and drag monitoring; the successful use of non-rotating drillpipe rubbers to reduce surface torque to acceptable levels; deeper casing setting depths, to minimize torque and drag, and to reduce time-dependent hole problems; the use of inhibitive/encapsulating mud systems for control of reactive clays/shales; and use of wellbore stability modeling. These advancements have helped EAL to drill 50% greater meterage than was expected in 1993, at 16% lower cost per meter. This paper chronicles the engineering decisions behind these advancements, their applications in the field, the success/failure story on Mackerel to date, and how these developments have been incorporated in EAL`s future well planning.

  2. Extending Validated Human Performance Models to Explore NextGen Concepts

    NASA Technical Reports Server (NTRS)

    Gore, Brian Francis; Hooey, Becky Lee; Mahlstedt, Eric; Foyle, David C.

    2012-01-01

    To meet the expected increases in air traffic demands, NASA and FAA are researching and developing Next Generation Air Transportation System (NextGen) concepts. NextGen will require substantial increases in the data available to pilots on the flight deck (e.g., weather,wake, traffic trajectory predictions, etc.) to support more precise and closely coordinated operations (e.g., self-separation, RNAV/RNP, and closely spaced parallel operations, CSPOs). These NextGen procedures and operations, along with the pilot's roles and responsibilities, must be designed with consideration of the pilot's capabilities and limitations. Failure to do so will leave the pilots, and thus the entire aviation system, vulnerable to error. A validated Man-machine Integration and design Analysis System (MIDAS) v5 model was extended to evaluate anticipated changes to flight deck and controller roles and responsibilities in NextGen approach and Land operations. Compared to conditions when the controllers are responsible for separation on decent to land phase of flight, the output from these model predictions suggest that the flight deck response time to detect the lead aircraft blunder will decrease, pilot scans to the navigation display will increase, and workload will increase.

  3. High Performance Plasma Operation on DIII-D During Extended Periods Without Boronization

    SciTech Connect

    West, W P; Groth, M; Hyatt, A W; Jackson, G L; Wade, M R; Greenfield, C M; Politzer, P A

    2007-06-27

    High performance plasmas, including both hybrid and advanced tokamak (AT) bench-mark discharges, were shown to be highly repeatable in DIII-D over 6000 plasma-seconds of operation during the 2006 campaign with no intervening boron depositions or high temperature bakes. Hybrid and AT discharges with identical control targets were repeated after the initial boronization at the beginning of the 2006 campaign, and again just before and after a second boronization near the end of the 2006 campaign. After a long entry vent between the 2006 and 2007 campaigns, similar discharges were again repeated after the standard high temperature baking and plasma cleanup, but prior to a boronization. Performance metrics, such as {beta}, confinement quality, and density control, were extremely well repeated. A low performance daily reference shot (DRS) was also established as a routine monitor of impurity influx. Over the 2006 campaign, the DRS database indicated little to no secular increase in impurity content. Oxygen content and Ni line emission were higher after the intervening vent, but were still minor contributors to plasma contamination. This indicates that erosion of boron films used for wall conditioning will not be a limitation to establishing long pulse high performance discharges in the new generation of superconducting tokamaks if graphite is used as the primary plasma facing material. These results contrast with recent work in devices using high-Z metallic plasma facing materials, where very frequent refreshing of boron films is required for high performance plasma operation.

  4. Clear differences in hand-held dermoscopes.

    PubMed

    Blum, Andreas; Jaworski, Simone

    2006-12-01

    In order to correctly evaluate melanocytic and non-melanocytic skin tumors using a hand-held dermoscope, it is essential to have adequate magnification and illumination to allow the differential structures to be clearly seen. One example of a dysplastic compound melanocytic nevus and a thin malignant melanoma were examined with five different handheld dermoscopes (Heine Delta 10, Heine Delta 20, Dermogenius and Dermlite Foto 37 with and without glass plate) in order to assess the image quality. The magnification was identical in all dermoscopes. In the newer dermoscopes (Heine Delta 20, Dermogenius and Dermlite Foto 37 with and without glass plate) the light sources were clearly improved, as now 6 or 24 LEDs, respectively, are employed. This distinctly improved the image quality with regard to color and visible differential structures compared to the dermoscope (Heine Delta 10) with only one light source. Clear differences is assessing differential structures were seen in one dermoscope (Dermlite Foto 37 without glass plate). Using this dermoscope without any glass plate or liquid between the dermoscope and the skin, exophytic tumors were better visualized in a three-dimensional fashion but fewer differential structures were seen. PMID:17176414

  5. A hand-held immaterial volumetric display

    NASA Astrophysics Data System (ADS)

    Sand, Antti; Rakkolainen, Ismo

    2014-03-01

    We have created an ultralight, movable, "immaterial" fogscreen. It is based on the fogscreen mid-air imaging technology. The hand-held unit is roughly the size and weight of an ordinary toaster. If the screen is tracked, it can be swept in the air to create mid-air slices of volumetric objects, or to show augmented reality (AR) content on top of real objects. Interfacing devices and methodologies, such as hand and gesture trackers, camera-based trackers and object recognition, can make the screen interactive. The user can easily interact with any physical object or virtual information, as the screen is permeable. Any real objects can be seen through the screen, instead of e.g., through a video-based augmented reality screen. It creates a mixed reality setup where both the real world object and the augmented reality content can be viewed and interacted with simultaneously. The hand-held mid-air screen can be used e.g., as a novel collaborating or classroom tool for individual students or small groups.

  6. Damage-Mitigating Control of Space Propulsion Systems for High Performance and Extended Life

    NASA Technical Reports Server (NTRS)

    Ray, Asok; Wu, Min-Kuang

    1994-01-01

    A major goal in the control of complex mechanical system such as spacecraft rocket engine's advanced aircraft, and power plants is to achieve high performance with increased reliability, component durability, and maintainability. The current practice of decision and control systems synthesis focuses on improving performance and diagnostic capabilities under constraints that often do not adequately represent the materials degradation. In view of the high performance requirements of the system and availability of improved materials, the lack of appropriate knowledge about the properties of these materials will lead to either less than achievable performance due to overly conservative design, or over-straining of the structure leading to unexpected failures and drastic reduction of the service life. The key idea in this report is that a significant improvement in service life could be achieved by a small reduction in the system dynamic performance. The major task is to characterize the damage generation process, and then utilize this information in a mathematical form to synthesize a control law that would meet the system requirements and simultaneously satisfy the constraints that are imposed by the material and structural properties of the critical components. The concept of damage mitigation is introduced for control of mechanical systems to achieve high performance with a prolonged life span. A model of fatigue damage dynamics is formulated in the continuous-time setting, instead of a cycle-based representation, for direct application to control systems synthesis. An optimal control policy is then formulated via nonlinear programming under specified constraints of the damage rate and accumulated damage. The results of simulation experiments for the transient upthrust of a bipropellant rocket engine are presented to demonstrate efficacy of the damage-mitigating control concept.

  7. Density, Expectation, and Extended Task Performance: An Experiment in the Natural Environment.

    ERIC Educational Resources Information Center

    Glassman, Joel B.; And Others

    1978-01-01

    The effects of density and expectation on academic performance and ratings of spatial and social satisfaction were investigated. Grade point averages and satisfaction measures compiled during the academic quarter were significantly negatively affected by exposure to density, demonstrating that density led to both greater dissatisfaction and more…

  8. Image Quality Characteristics of Handheld Display Devices for Medical Imaging

    PubMed Central

    Yamazaki, Asumi; Liu, Peter; Cheng, Wei-Chung; Badano, Aldo

    2013-01-01

    Handheld devices such as mobile phones and tablet computers have become widespread with thousands of available software applications. Recently, handhelds are being proposed as part of medical imaging solutions, especially in emergency medicine, where immediate consultation is required. However, handheld devices differ significantly from medical workstation displays in terms of display characteristics. Moreover, the characteristics vary significantly among device types. We investigate the image quality characteristics of various handheld devices with respect to luminance response, spatial resolution, spatial noise, and reflectance. We show that the luminance characteristics of the handheld displays are different from those of workstation displays complying with grayscale standard target response suggesting that luminance calibration might be needed. Our results also demonstrate that the spatial characteristics of handhelds can surpass those of medical workstation displays particularly for recent generation devices. While a 5 mega-pixel monochrome workstation display has horizontal and vertical modulation transfer factors of 0.52 and 0.47 at the Nyquist frequency, the handheld displays released after 2011 can have values higher than 0.63 at the respective Nyquist frequencies. The noise power spectra for workstation displays are higher than 1.2×10−5 mm2 at 1 mm−1, while handheld displays have values lower than 3.7×10−6 mm2. Reflectance measurements on some of the handheld displays are consistent with measurements for workstation displays with, in some cases, low specular and diffuse reflectance coefficients. The variability of the characterization results among devices due to the different technological features indicates that image quality varies greatly among handheld display devices. PMID:24236113

  9. Do Handheld Devices Facilitate Face-to-Face Collaboration? Handheld Devices with Large Shared Display Groupware to Facilitate Group Interactions

    ERIC Educational Resources Information Center

    Liu, Chen-Chung; Kao, L.-C.

    2007-01-01

    One-to-one computing environments change and improve classroom dynamics as individual students can bring handheld devices fitted with wireless communication capabilities into the classrooms. However, the screens of handheld devices, being designed for individual-user mobile application, limit promotion of interaction among groups of learners. This…

  10. Extending the SAFRAN meteorological analysis system to the Iberian Peninsula and the Balearic Islands. Analysis of its performance and applications.

    NASA Astrophysics Data System (ADS)

    Quintana-Seguí, Pere; Míguez-Macho, Gonzalo; Llasat, María del Carmen

    2015-04-01

    Within the FP7 eartH2Observe project we are studying the ability of different LSMs to simulate the processes of drought on the Iberian Peninsula. In order to perform our simulations we need a good atmospheric forcing dataset that covers the whole area of study at the right resolution (5 km in hour case). Currently, in Spain, there are some high resolution datasets, but none of them have all the variables necessary to run a LSM. Thus, we decided to extend the SAFRAN meteorological analysis system to the whole Iberian Peninsula and the Balearic Islands. SAFRAN uses optimal interpolation to analyze the variables of interest using all available observed data (from AEMET's network) and a first guess (ERA-Interim). SAFRAN, which was developed by Météo France to force its LSMs (CROCUS for snow, ISBA and SURFEX for hydrological studies), was recently extended to the Ebro basin in a pilot study that covered only three years. In eartH2Observe we are extending it to cover the 1995-2007 period. This period is not long enough to study climate variability, but it already useful to a range of studies that need a decade long dataset. In the future, we plan to extend SAFRAN to a period that covers several decades. We present the SAFRAN analysis system, its main features and its performance in the study area. In addition, we also present a first comparison with alternative databases in the context of the eartH2Observe Spanish Case Study. In the future, we expect SAFRAN to be useful, not only to large scale hydrology projects, but also to a large range of projects simulating land surface processes for other purposes. SAFRAN will also be useful as reference dataset for downscaling climate simulations. Thus, we also discuss these applications.

  11. Extended performance electric propulsion power processor design study. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Biess, J. J.; Inouye, L. Y.; Schoenfeld, A. D.

    1977-01-01

    Several power processor design concepts were evaluated and compared. Emphasis was placed on a 30cm ion thruster power processor with a beam supply rating of 2.2kW to 10kW. Extensions in power processor performance were defined and were designed in sufficient detail to determine efficiency, component weight, part count, reliability and thermal control. Preliminary electrical design, mechanical design, and thermal analysis were performed on a 6kW power transformer for the beam supply. Bi-Mod mechanical, structural, and thermal control configurations were evaluated for the power processor, and preliminary estimates of mechanical weight were determined. A program development plan was formulated that outlines the work breakdown structure for the development, qualification and fabrication of the power processor flight hardware.

  12. Productivity enhancements using hand-held computers: a case study.

    PubMed

    Bruns, B J

    1991-01-01

    In closing, the benefits of computerizing the equipment control information system have been assessed qualitatively and, to an extent, quantitatively. We have seen a drastic improvement in the operation of the clinical engineering department. Equipment repair and inspection results are readily accessible for technician use. Equipment service reports are typed and easy to read. Accountability of repair parts are immediately available for restocking and financial needs. Feedback reports are generated on a regular and timely basis. We have shown a reduction of around 12 minutes in the inspection procedure. This time has been directly linked to the automation of the inspection process using hand-held computers. The cost of automation was inexpensive, as the hand-held computers cost around 500 dollars per unit. Currently, the devices are used by any technician who performs inspections outside the department. The units time the inspection process and record the inspection result. We have interfaced the units to portable bar-code printers that produce an inspection label on-site. In the future, bar-code wands and guns will be used to streamline the data entry process of the inspection. A reduction in the number of incorrectly typed ECNs will improve the integrity of the database. The use of bar-codes will eventually spread to the parts' system. This will improve tracking, ordering, and inventorying repair parts. The plan is to improve the documentation of these parts and ease the analysis of new equipment needs, manufacturer reliability, and contract evaluations. At the present, we are addressing the problem of preparation time.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2032064

  13. Hand-held echocardiography: its use and usefulness.

    PubMed

    Mondillo, Sergio; Giannotti, Giovanna; Innelli, Pasquale; Ballo, Pier Carlo; Galderisi, Maurizio

    2006-07-28

    In recent years, several echocardiographic hand-held devices have been developed and are now available for a growing number of cardiologists. After the first clinical use 25 years ago, hand-held echocardiography (HHE) is now earning important commercial positions. Their transportability permits echo performance out the echo-labs and offers the possibility to make diagnosis in intensive care unit, emergency room, outpatient clinic, at the bedside, and even in ambulance. Experiences in the clinical setting have demonstrated the ability of HHE to detect multiple diseases including abdominal aortic aneurysms, left ventricular hypertrophy, regional wall motion abnormalities, pericardial and pleural effusions. At the present time, four varieties of HHE have to be recognized: the first includes high-cost, miniaturized machines, similar to the most advanced instrumentations, provided by new tools and imaging transfer systems; a second intermediate, middle-cost variety encompasses devices corresponding to standard echocardiography, but not miniaturized; according to the definition of the American Society of Echocardiography, a third and a fourth category comprise machines of weight lower than 2.7 kg, battery supplied and appropriately defined as "portable cardioschopes", which can be utilized as a technical refinement of physical examination. The use of HHE opens main controversy concerning their diagnostic accuracy, the opportunity to establish in which clinical settings they should be used and the identification of both potential users and required competence level. Preliminary experiences show the possibility to improve and anticipate diagnosis of several cardiovascular diseases but also the need to plan specific ultrasound training to avoid incorrect use of HHE. PMID:16087257

  14. Damage-mitigating control of space propulsion systems for high performance and extended life

    NASA Technical Reports Server (NTRS)

    Ray, Asok; Wu, Min-Kuang; Dai, Xiaowen; Carpino, Marc; Lorenzo, Carl F.

    1993-01-01

    Calculations are presented showing that a substantial improvement in service life of a reusable rocket engine can be achieved by an insignificant reduction in the system dynamic performance. The paper introduces the concept of damage mitigation and formulates a continuous-time model of fatigue damage dynamics. For control of complex mechanical systems, damage prediction and damage mitigation are carried out based on the available sensory and operational information such that the plant can be inexpensively maintained and safely and efficiently steered under diverse operating conditions. The results of simulation experiments are presented for transient operations of a reusable rocket engine.

  15. An extended life and performance test of a low-power arcjet

    NASA Technical Reports Server (NTRS)

    Curran, Francis M.; Haag, Thomas W.

    1988-01-01

    An automated, cyclic life test was performed to demonstrate the reliability and endurance of a low power dc cycle arcjet thruster. Over 1000 hr and 500 on-off cycles were accumulated which would represent the requirements for about 15 years of on-orbit lifetime. A hydrogen/nitrogen propellant mixture was used to simulate decomposed hydrazine propellant and the power level was nominally 1.2 kW after the burn-in period. The arcjet operated in a very repeatable fashion from cycle to cycle. The steady state voltage increased by approximately 6 V over the first 300 hr, and then by only 3 V through the remainder of the test. Thrust measurements taken before, during, and after the test verified that the thruster performed in a consistent fashion throughout the tests at a specific impulse of 450 to 460 sec. Post-test component evaluation revealed limited erosion on both the anode and cathode. Other thruster components, including graphite seals, appeared undamaged.

  16. Using Automated Code Generation to Support High Performance Extended MHD Integration in OpenGGCM

    NASA Astrophysics Data System (ADS)

    Germaschewski, K.; Raeder, J.

    2011-10-01

    Automatic code generation is a technique that takes the specification of an algorithm at a high abstraction level and turns it into a well-tuned computer code. For finite-volume / finite-difference based discretizations, this higher abstraction level can be a stencil computation. At the backend, the code generator features modules which generate optimal code for specific hardware architectures, for example conventional architectures (x86) using SIMD instructions (e.g. SSE2), or heterogeneous architectures like the Cell processor or GPGPUs. The definition of the computation is agnostic to the actual hardware used, as a high-performance implementation tailored to the specific architecture will be generated automatically. The OpenGGCM code, a global magnetosphere model, has been converted to use an automatically generated implementation of its magnetohydrodynamics (MHD) integrator. The new version enables us to take advantage of the Cell processor's computational capability and also shows performance improvements of up to 2.3× on a conventional Intel processor. The code generation approach also facilitated the recent extension of the MHD model to incorporate Hall physics.

  17. Damage-mitigating control of a reusable rocket engine for high performance and extended life

    NASA Technical Reports Server (NTRS)

    Ray, Asok; Dai, Xiaowen

    1995-01-01

    The goal of damage mitigating control in reusable rocket engines is to achieve high performance with increased durability of mechanical structures such that functional lives of the critical components are increased. The major benefit is an increase in structural durability with no significant loss of performance. This report investigates the feasibility of damage mitigating control of reusable rocket engines. Phenomenological models of creep and thermo-mechanical fatigue damage have been formulated in the state-variable setting such that these models can be combined with the plant model of a reusable rocket engine, such as the Space Shuttle Main Engine (SSME), for synthesizing an optimal control policy. Specifically, a creep damage model of the main thrust chamber wall is analytically derived based on the theories of sandwich beam and viscoplasticity. This model characterizes progressive bulging-out and incremental thinning of the coolant channel ligament leading to its eventual failure by tensile rupture. The objective is to generate a closed form solution of the wall thin-out phenomenon in real time where the ligament geometry is continuously updated to account for the resulting deformation. The results are in agreement with those obtained from the finite element analyses and experimental observation for both Oxygen Free High Conductivity (OFHC) copper and a copper-zerconium-silver alloy called NARloy-Z. Due to its computational efficiency, this damage model is suitable for on-line applications of life prediction and damage mitigating control, and also permits parametric studies for off-line synthesis of damage mitigating control systems. The results are presented to demonstrate the potential of life extension of reusable rocket engines via damage mitigating control. The control system has also been simulated on a testbed to observe how the damage at different critical points can be traded off without any significant loss of engine performance. The research work

  18. Extending single mode performance of all-solid large-mode-area single trench fiber.

    PubMed

    Jain, D; Jung, Y; Nunez-Velazquez, M; Sahu, J K

    2014-12-15

    We report a novel "single trench fiber" design for mode area scaling of the fundamental mode while offering effective single mode operation for a compact fiber laser device. This fiber design allows very high suppression of the higher order modes by offering high loss and power delocalization. It has the advantages of low cost and easy fabrication thanks to all solid fiber design, cylindrical symmetry, and higher refractive index of core as that of the cladding. A Yb-doped single trench fiber with a 40 µm core diameter has been fabricated from modified chemical vapor deposition process in conjunction with solution-doping offering an effective mode area of as large as ~1,000 µm(2) at 1,060 nm for the bend radius of 20 cm. Detailed characterizations confirm a robust single mode behavior of the fiber. Comparative analysis with other fiber designs shows significant performance enhancement of effective single mode operation suitable for fiber laser applications. PMID:25607057

  19. Extending PowerPack for Profiling and Analysis of High Performance Accelerator-Based Systems

    SciTech Connect

    Li, Bo; Chang, Hung-Ching; Song, Shuaiwen; Su, Chun-Yi; Meyer, Timmy; Mooring, John; Cameron, Kirk

    2014-12-01

    Accelerators offer a substantial increase in efficiency for high-performance systems offering speedups for computational applications that leverage hardware support for highly-parallel codes. However, the power use of some accelerators exceeds 200 watts at idle which means use at exascale comes at a significant increase in power at a time when we face a power ceiling of about 20 megawatts. Despite the growing domination of accelerator-based systems in the Top500 and Green500 lists of fastest and most efficient supercomputers, there are few detailed studies comparing the power and energy use of common accelerators. In this work, we conduct detailed experimental studies of the power usage and distribution of Xeon-Phi-based systems in comparison to the NVIDIA Tesla and at SandyBridge.

  20. Caffeine administration at night during extended wakefulness effectively mitigates performance impairment but not subjective assessments of fatigue and sleepiness.

    PubMed

    Paech, Gemma M; Banks, Siobhan; Pajcin, Maja; Grant, Crystal; Johnson, Kayla; Kamimori, Gary H; Vedova, Chris B Della

    2016-06-01

    The current study investigated the effects of repeated caffeine administration on performance and subjective reports of sleepiness and fatigue during 50h extended wakefulness. Twenty-four, non-smokers aged 22.5±2.9y (mean±SD) remained awake for two nights (50h) in a controlled laboratory environment. During this period, 200mg of caffeine or placebo gum was administered at 01:00, 03:00, 05:00 and 07:00 on both nights (total of 800mg/night). Neurobehavioral performance and subjective reports were assessed throughout the wake period. Caffeine improved performance compared to placebo, but did not affect overall ratings of subjective sleepiness and fatigue. Performance and sleepiness worsened with increasing time awake for both conditions. However, caffeine slowed performance impairments such that after 50h of wakefulness performance was better following caffeine administration compared to placebo. Caffeine also slowed the increase in subjective sleepiness and performance ratings, but only during the first night of wakefulness. After two nights of sleep deprivation, there was no difference in sleepiness ratings between the two conditions. These results demonstrate that strategic administration of caffeine effectively mitigates performance impairments associated with 50h wakefulness but does not improve overall subjective assessments of sleepiness, fatigue and performance. Results indicate that while performance impairment is alleviated, individuals may continue to report feelings of sleepiness. Individuals who use caffeine as a countermeasure in sustained operations may feel as though caffeine is not effective despite impairments in objective performance being largely mitigated. PMID:27061779

  1. Correlation and Agreement of Handheld Spirometry with Laboratory Spirometry in Allogeneic Hematopoietic Cell Transplant Recipients.

    PubMed

    Cheng, Guang-Shing; Campbell, Angela P; Xie, Hu; Stednick, Zach; Callais, Cheryl; Leisenring, Wendy M; Englund, Janet A; Chien, Jason W; Boeckh, Michael

    2016-05-01

    Early detection of subclinical lung function decline may help identify allogeneic hematopoietic cell transplant (HCT) recipients who are at increased risk for late noninfectious pulmonary complications, including bronchiolitis obliterans syndrome. We evaluated the use of handheld spirometry in this population. Allogeneic HCT recipients enrolled in a single-center observational trial performed weekly spirometry with a handheld spirometer for 1 year after transplantation. Participants performed pulmonary function tests in an outpatient laboratory setting at 3 time points: before transplantation, at day 80 after transplantation, and at 1 year after transplantation. Correlation between the 2 methods was assessed by Pearson and Spearman correlations; agreement was assessed using Bland-Altman plots. A total of 437 subjects had evaluable pulmonary function tests. Correlation for forced expiratory volume in 1 second (FEV1) was r = .954 (P < .0001) at day 80 and r = .931 (P < .0001) at 1 year when the handheld and laboratory tests were performed within 1 day of each other. Correlation for handheld forced expiratory volume in 6 seconds (FEV6) with laboratory forced vital capacity was r = .914 (P < .0001) at day 80 and r = .826 (P < .0001) at 1 year. The bias, or the mean difference (handheld minus laboratory), for FEV1 at day 80 and 1 year was -.13 L (limits of agreement, -.63 to .37) and -.10 L (limits of agreement, -.77 to .56), respectively. FEV6 showed greater bias at day 80 (-.51 L [limits of agreement, -1.44 to .42]) and 1 year (-.40 L [limits of agreement, -1.81 to 1.01]). Handheld spirometry correlated well with laboratory spirometry after allogeneic HCT and may be useful for self-monitoring of patients for early identification of airflow obstruction. PMID:26748162

  2. Low cost booster and high performance orbit injection propulsion extended abstract

    NASA Technical Reports Server (NTRS)

    Sackheim, R. L.

    1994-01-01

    Space transportation is currently a major element of cost for communications satellite systems. For every dollar spent in manufacturing the satellite, somewhere between 1 and 3 dollars must be spent to launch the satellite into its initial operational orbit. This also makes the weight of the satellite a very critical cost factor because it is important to maximize the useful payload that is placed into orbit to maximize the return on the original investment. It seems apparent then, that tremendous economic advantage for satellite communications systems can be gained from improvements in two key highly leveraged propulsion areas. The first and most important economic improvement can be achieved by significantly lowering the cost of today's launch vehicles. The second gain that would greatly benefit the communications satellite business position is to increase both the useful (payload) weight placed into the orbit and the revenue generating lifetime of the satellite on-orbit. The point of this paper is to first explain that these two goals can best be achieved by cost reduction and performance increasing advancements in rocket propulsion for both the launch vehicle and for the satellite on-board apogee insertion and on-orbit velocity control systems.

  3. Compact handheld digital holographic microscopy system development

    NASA Astrophysics Data System (ADS)

    Singh, Vijay Raj; Sui, Liansheng; Asundi, Anand

    2009-12-01

    Development of a commercial prototype of reflection handheld digital holographic microscope system is presented in this paper. The concept is based on lensless magnification using diverging wave geometry and the miniaturized optical design which provides a compact packaged system. The optical geometry design provides the same curvature of object and reference waves and thus phase aberration is automatically compensated. The basic methodology of the system is developed and it further explored for 3D imaging, static deflection and vibration measurements applications. Based on the developed methodology an user-friendly software is developed suitable for industrial shop floor environment. The applications of the system are presented for 3D imaging, static deflection measurement and vibration analysis of MEMS samples. The developed system is well suitable for the testing of MEMS and Microsystems samples, with full-field and real-time features, for static and dynamic inspection and characterization and to monitor micro-fabrication process.

  4. Compact handheld digital holographic microscopy system development

    NASA Astrophysics Data System (ADS)

    Singh, Vijay Raj; Sui, Liansheng; Asundi, Anand

    2010-03-01

    Development of a commercial prototype of reflection handheld digital holographic microscope system is presented in this paper. The concept is based on lensless magnification using diverging wave geometry and the miniaturized optical design which provides a compact packaged system. The optical geometry design provides the same curvature of object and reference waves and thus phase aberration is automatically compensated. The basic methodology of the system is developed and it further explored for 3D imaging, static deflection and vibration measurements applications. Based on the developed methodology an user-friendly software is developed suitable for industrial shop floor environment. The applications of the system are presented for 3D imaging, static deflection measurement and vibration analysis of MEMS samples. The developed system is well suitable for the testing of MEMS and Microsystems samples, with full-field and real-time features, for static and dynamic inspection and characterization and to monitor micro-fabrication process.

  5. Optical links in handheld multimedia devices

    NASA Astrophysics Data System (ADS)

    van Geffen, S.; Duis, J.; Miller, R.

    2008-04-01

    Ever emerging applications in handheld multimedia devices such as mobile phones, laptop computers, portable video games and digital cameras requiring increased screen resolutions are driving higher aggregate bitrates between host processor and display(s) enabling services such as mobile video conferencing, video on demand and TV broadcasting. Larger displays and smaller phones require complex mechanical 3D hinge configurations striving to combine maximum functionality with compact building volumes. Conventional galvanic interconnections such as Micro-Coax and FPC carrying parallel digital data between host processor and display module may produce Electromagnetic Interference (EMI) and bandwidth limitations caused by small cable size and tight cable bends. To reduce the number of signals through a hinge, the mobile phone industry, organized in the MIPI (Mobile Industry Processor Interface) alliance, is currently defining an electrical interface transmitting serialized digital data at speeds >1Gbps. This interface allows for electrical or optical interconnects. Above 1Gbps optical links may offer a cost effective alternative because of their flexibility, increased bandwidth and immunity to EMI. This paper describes the development of optical links for handheld communication devices. A cable assembly based on a special Plastic Optical Fiber (POF) selected for its mechanical durability is terminated with a small form factor molded lens assembly which interfaces between an 850nm VCSEL transmitter and a receiving device on the printed circuit board of the display module. A statistical approach based on a Lean Design For Six Sigma (LDFSS) roadmap for new product development tries to find an optimum link definition which will be robust and low cost meeting the power consumption requirements appropriate for battery operated systems.

  6. Acute Physiological and Thermoregulatory Responses to Extended Interval Training in Endurance Runners: Influence of Athletic Performance and Age

    PubMed Central

    García-Pinillos, Felipe; Soto-Hermoso, Víctor Manuel; Latorre-Román, Pedro Ángel

    2015-01-01

    This study aimed to describe the acute impact of extended interval training (EIT) on physiological and thermoregulatory levels, as well as to determine the influence of athletic performance and age effect on the aforementioned response in endurance runners. Thirty-one experienced recreational male endurance runners voluntarily participated in this study. Subjects performed EIT on an outdoor running track, which consisted of 12 runs of 400 m. The rate of perceived exertion, physiological response through the peak and recovery heart rate, blood lactate, and thermoregulatory response through tympanic temperature, were controlled. A repeated measures analysis revealed significant differences throughout EIT in examined variables. Cluster analysis grouped according to the average performance in 400 m runs led to distinguish between athletes with a higher and lower sports level. Cluster analysis was also performed according to age, obtaining an older group and a younger group. The one-way analysis of variance between groups revealed no significant differences (p≥0.05) in the response to EIT. The results provide a detailed description of physiological and thermoregulatory responses to EIT in experienced endurance runners. This allows a better understanding of the impact of a common training stimulus on the physiological level inducing greater accuracy in the training prescription. Moreover, despite the differences in athletic performance or age, the acute physiological and thermoregulatory responses in endurance runners were similar, as long as EIT was performed at similar relative intensity. PMID:26839621

  7. Application of a Constant Gain Extended Kalman Filter for In-Flight Estimation of Aircraft Engine Performance Parameters

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L.; Litt, Jonathan S.

    2005-01-01

    An approach based on the Constant Gain Extended Kalman Filter (CGEKF) technique is investigated for the in-flight estimation of non-measurable performance parameters of aircraft engines. Performance parameters, such as thrust and stall margins, provide crucial information for operating an aircraft engine in a safe and efficient manner, but they cannot be directly measured during flight. A technique to accurately estimate these parameters is, therefore, essential for further enhancement of engine operation. In this paper, a CGEKF is developed by combining an on-board engine model and a single Kalman gain matrix. In order to make the on-board engine model adaptive to the real engine s performance variations due to degradation or anomalies, the CGEKF is designed with the ability to adjust its performance through the adjustment of artificial parameters called tuning parameters. With this design approach, the CGEKF can maintain accurate estimation performance when it is applied to aircraft engines at offnominal conditions. The performance of the CGEKF is evaluated in a simulation environment using numerous component degradation and fault scenarios at multiple operating conditions.

  8. Acute Physiological and Thermoregulatory Responses to Extended Interval Training in Endurance Runners: Influence of Athletic Performance and Age.

    PubMed

    García-Pinillos, Felipe; Soto-Hermoso, Víctor Manuel; Latorre-Román, Pedro Ángel

    2015-12-22

    This study aimed to describe the acute impact of extended interval training (EIT) on physiological and thermoregulatory levels, as well as to determine the influence of athletic performance and age effect on the aforementioned response in endurance runners. Thirty-one experienced recreational male endurance runners voluntarily participated in this study. Subjects performed EIT on an outdoor running track, which consisted of 12 runs of 400 m. The rate of perceived exertion, physiological response through the peak and recovery heart rate, blood lactate, and thermoregulatory response through tympanic temperature, were controlled. A repeated measures analysis revealed significant differences throughout EIT in examined variables. Cluster analysis grouped according to the average performance in 400 m runs led to distinguish between athletes with a higher and lower sports level. Cluster analysis was also performed according to age, obtaining an older group and a younger group. The one-way analysis of variance between groups revealed no significant differences (p≥0.05) in the response to EIT. The results provide a detailed description of physiological and thermoregulatory responses to EIT in experienced endurance runners. This allows a better understanding of the impact of a common training stimulus on the physiological level inducing greater accuracy in the training prescription. Moreover, despite the differences in athletic performance or age, the acute physiological and thermoregulatory responses in endurance runners were similar, as long as EIT was performed at similar relative intensity. PMID:26839621

  9. Evaluating change in user error when using ruggedized handheld devices.

    PubMed

    Cannon, Angela Brooke; Strawderman, Lesley; Burch, Reuben

    2015-11-01

    The increasing number of handheld mobile devices used today and the increasing dependency on them in the workplace makes understanding how users interact with these devices critical. This study seeks to understand how user error changes based on user age as well as input content type on ruggedized handheld devices. Participants completed data entry tasks of word and character input on two different devices, a physical keypad and touchscreen device. The number of errors and types of error, corrected and permanent were collected for each participant. Based on results on the study, touchscreen devices proved to be the optimal ruggedized handheld device to minimize user error. PMID:26154226

  10. Applications of GIS and a Handheld XRF for Mapping Cu and Pb Contaminations in Abandoned Mine Areas

    NASA Astrophysics Data System (ADS)

    Lee, H.; Choi, Y.; Yi, H.; Kim, D. H.

    2014-12-01

    In this study, we used a handheld X-Ray Fluorescence (XRF) and Geographic Information Systems (GIS) to create soil contamination maps regarding Cu and Pb around abandoned mining areas. The Busan abandoned mine in Korea was selected as a study area. Digital Elevation Models (DEMs)-based Terrain analysis was performed to identify locations for investigating the soil contamination. At the locations, Cu and Pb contaminations were investigated by using the handheld XRF. The field investigation data were inputted into GIS and utilized to create soil contamination maps using the ordinary kriging method (one of the geostatistical interpolation techniques used in GIS). High concentrations of Cu and Pb were shown at the waste and tailings dumps around abandoned mine openings. As a result, we could know that the method for creating soil contamination maps using a handheld and GIS can be utilized effectively.

  11. An analysis of sweep patterns for a handheld demining system

    NASA Astrophysics Data System (ADS)

    Wilson, J. N.; Gader, P. D.; Ho, K. C.; Mazhar, R.

    2006-05-01

    Handheld sensors are commonly used to assist in landmine location and removal. A number of computer systems aimed at assisting humans in discriminating between buried mines and other objects have been developed. Each such system requires some protocol that involves sweeping the sensor over a region of ground using some set of patterns to search for objects (detection) and determine the nature of those objects (discrimination). The work reported here is an effort to determine an acceptable sweep pattern for mine/nonmine discrimination that provides good performance while still being simple for the operator to use. The paper describes a series of data collections and case studies employing a combined radar and metal detection sensor. The system was evaluated first using a robotic operator and later human operators. We discuss the application of a supervised learning system discriminator to each data set, and evaluate discrimination performance. We found that using a relatively simple sweep pattern, computer algorithms can achieve better discrimination performance than an expert human operator, and that (at least up to ten sweeps) our computer algorithm performs better with more sweeps over target.

  12. HANDHELD DETAIL OF BRIDGE IN FORMER LOCATION SPANNING GANARGUA CREEK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    HANDHELD DETAIL OF BRIDGE IN FORMER LOCATION SPANNING GANARGUA CREEK (MACEDON, NY), VIEW FROM SOUTHEAST. - Aldrich Towing-Path Change Bridge, Spanning New York State Heritage Trail, Aqueduct Park (moved from Macedon, NY), Palmyra, Wayne County, NY

  13. How do students with dyslexia perform in extended matching questions, short answer questions and observed structured clinical examinations?

    PubMed

    Gibson, Sandra; Leinster, Samuel

    2011-08-01

    There are an increasing number of students with learning difficulties attending university, and currently much debate about the suitability and ability of students with dyslexia at both medical school and once they graduate into clinical practice. In this study we describe the performance of students with dyslexia compared to fellow students in extended matching questions (EMQ), short answer question (SAQ) and observed structured clinical examinations (OSCE) and discuss the implications of differences identified. End of year assessment results for 5 cohorts of medical students were analysed. Students with dyslexia did less well overall in all assessment types in year 1 but this difference was not evident in later years. Dyslexic students who were allowed extra time in written assessments did better than dyslexic students who did not have their assessment concessions in place. When station type within OSCE assessments was analysed students with dyslexia did less well in both examination skills and data interpretation stations in years 1, 2 & 3. In conclusion, differences in performance in written assessments are only evident early in training and may be partly due to delayed adjustment to medical school or implementation of assessment concessions. Performance in individual OSCE stations is dependent on station type. Why students with specific learning difficulties (SpLDs) perform less well in examination skills and data analysis OSCE stations requires further investigation. PMID:21249518

  14. Computer implemented method, and apparatus for controlling a hand-held tool

    NASA Technical Reports Server (NTRS)

    Wagner, Kenneth William (Inventor); Taylor, James Clayton (Inventor)

    1999-01-01

    The invention described here in is a computer-implemented method and apparatus for controlling a hand-held tool. In particular, the control of a hand held tool is for the purpose of controlling the speed of a fastener interface mechanism and the torque applied to fasteners by the fastener interface mechanism of the hand-held tool and monitoring the operating parameters of the tool. The control is embodied in intool software embedded on a processor within the tool which also communicates with remote software. An operator can run the tool, or through the interaction of both software, operate the tool from a remote location, analyze data from a performance history recorded by the tool, and select various torque and speed parameters for each fastener.

  15. SkinScan©: A PORTABLE LIBRARY FOR MELANOMA DETECTION ON HANDHELD DEVICES.

    PubMed

    Wadhawan, Tarun; Situ, Ning; Lancaster, Keith; Yuan, Xiaojing; Zouridakis, George

    2011-03-30

    We have developed a portable library for automated detection of melanoma termed SkinScan© that can be used on smartphones and other handheld devices. Compared to desktop computers, embedded processors have limited processing speed, memory, and power, but they have the advantage of portability and low cost. In this study we explored the feasibility of running a sophisticated application for automated skin cancer detection on an Apple iPhone 4. Our results demonstrate that the proposed library with the advanced image processing and analysis algorithms has excellent performance on handheld and desktop computers. Therefore, deployment of smartphones as screening devices for skin cancer and other skin diseases can have a significant impact on health care delivery in underserved and remote areas. PMID:21892382

  16. Developing an SDK of usability-engineered handheld evaluation aid.

    PubMed

    Hsu, Chiao-Ling; Chang, Polun

    2007-01-01

    Handheld devices are useful tools to collect date at practice settings. However, it takes time and is very challenging for healthcare professionals to design a usability-engineered system. This study is to upgrade our practically-proven easy to use and effective handheld systems to an SDK. The SDK are composed of Excel-based form designer and Palm-based template. We have successfully tested the prototype in developing a 407-question homecare evaluation support system. PMID:18694082

  17. Electronic, Hand-Held, Wireless Text-And-Graphics Viewer

    NASA Technical Reports Server (NTRS)

    Palumbo, Daniel L.

    1994-01-01

    Proposed electronic, hand-held, wireless viewer presents written material to reader in way that closely resembles that of paper reading material. Viewer presents text and graphics like those normally found in books, newspapers, and magazines. Its hand-held and wireless features enable it to be used in positions and areas where books and magazines are normally used. Device consists primarily of two parts: the receiver/information store and viewing screen.

  18. Automated Hand-Held UXO Detection, Classification & Discrimination Sensor

    SciTech Connect

    Bell, Thomas H.

    2000-06-12

    The research focused on procedures for target discrimination and classification using hand-held EMI sensors. The idea is to have a small, portable sensor that can be operated in a sweep or similar pattern in front of the operator, and that is capable of distinguishing between buried UXO and clutter on the spot. Curing Phase 1, we developed the processing techniques for distinguishing between buried UXO and clutter using the EM61-HH hand-held metal detector.

  19. High-Tech versus Low-Tech Instructional Strategies: A Comparison of Clickers and Handheld Response Cards

    ERIC Educational Resources Information Center

    Fallon, Marianne; Forrest, Stacey L.

    2011-01-01

    Although the use of clickers (classroom response systems) has been widely investigated, fewer studies directly compared outcomes for clickers with other active response methods, such as handheld response cards. We measured students' test performance and their self-reported anxiety and hope for upcoming tests after attending review sessions for an…

  20. Preliminary fire extinguishing tests with handheld bottles: A comparison of extinguishing compounds

    NASA Astrophysics Data System (ADS)

    Guastavino, T. M.; Fann, F.

    1990-01-01

    In 1982, the Federal Aviation Administration (FAA) Technical Center completed a test and evaluation project on use of handheld extinguishers in transport category aircraft. Some of the tests involved the comparative effectiveness of handheld extinguishers in a specific fire scenario: a triple non-fireblocked aircraft seat ignited with gasoline. The test work included the identification and quantification of effluent gas species produced by the fire and the extinguishing chemicals. The comparative effectiveness of the extinguishers used in the above tests and some newer systems in two distinct fire tests are described. The first test is the crib test used by Underwriters Laboratory, Inc. to rate handheld estinguishers. The second test is the same seat test used in the earlier work. The tests employed aircraft approved water extinguishers and Halon 1211 extinguishers as benchmarks. New formulations using surfactants and extinguishing powders in aqueous solutions were tested against the benchmark performance levels. In these tests, certain new solutions were able to meet or exceed the performance of the benchmark agents.

  1. A hand-held micro surgical device for contact force regulation against involuntary movements.

    PubMed

    Seulki Kyeong; Dongjune Chang; Yunjoo Kim; Gwang Min Gu; Seungkey Lee; Soohoa Jeong; Jung Kim

    2015-08-01

    Involuntary movements such as heart beating in surgical environment and surgeon's tremor disturb a micro surgical manipulation and cause a risk of patient wound. Although the delicate operation is performed by a skilled surgeon, the sensitivity of the surgeon is limited to quantify the range of safe contact forces. In this paper, we developed a compact hand-held surgical device to maintain a required contact force to maintain a required contact force using a custom force sensor and a linear delta mechanism. The custom optical force sensor measured the contact force of the device tip and the linear delta mechanism compensated undesired forces to maintain a consistent contact force. The proposed device is consisted of force sensing unit and actuating unit. The device was improved from our previous Linear Delta mechanism based prototype in terms of size, weight, and force sensing capability. The developed device was validated by investigation of contact force accuracy in a fixed condition and a hand-held condition. In hand-held condition, the visual feedback of the current contact force was provided, and the performance of the contact force regulation was investigated by comparing the root mean square (RMS) contact force errors and standard deviation in with and without control cases. The fluctuation (less than 50 mN) of the force regulation control of the device showed the feasibility of the device for the use in delicate operations. PMID:26736400

  2. Demonstration Report: Handheld UXO Discriminator, SERDP No. MR-1667

    SciTech Connect

    Gasperikova, E.

    2010-09-01

    In 2003, the Defense Science Board observed: 'The problem is that instruments that can detect the buried UXOs also detect numerous scrap metal objects and other artifacts, which leads to an enormous amount of expensive digging. Typically 100 holes may be dug before a real UXO is unearthed! The Task Force assessment is that much of this wasteful digging can be eliminated by the use of more advanced technology instruments that exploit modern digital processing and advanced multi-mode sensors to achieve an improved level of discrimination of scrap from UXOs.' In keeping with these remarks and with prior funding (UX-1225, MM-0437, and MM-0838), the LBNL group has successfully designed and built the cart-mounted Berkeley UXO Discriminator (BUD) and demonstrated its performance at various test sites (cf. Gasperikova et al., 2007, 2008, and 2009). Because hand-held systems have the advantage of being lightweight, compact, portable, and deployable under most site conditions, they are particularly useful in areas of dense vegetation or challenging terrain. In heavily wooded areas or areas with steep or uneven terrain, hand-held sensors may be the only suitable device for UXO detection and discrimination because it can be carried through spaces that the operator could walk through or at least approach. Furthermore, it is desirable to find and characterize a metallic object without the need to accurately locate the sensors at multiple positions around the target. The ideal system would thus locate and characterize the target from a single position of the sensor and indicate to the operator where to flag the target for subsequent study. Based on these considerations, we designed and built a sensor package in a shape of a 14-in (0.35 m) cube. This hand-held prototype incorporates the key features of the cart-mounted system - (a) three orthogonal transmitters and ten pairs of receivers, and (b) difference or gradient measurements that significantly reduce the ambient and motion

  3. Performance of high-convergence, layered DT implosions with extended-duration pulses at the National Ignition Facility.

    PubMed

    Smalyuk, V A; Atherton, L J; Benedetti, L R; Bionta, R; Bleuel, D; Bond, E; Bradley, D K; Caggiano, J; Callahan, D A; Casey, D T; Celliers, P M; Cerjan, C J; Clark, D; Dewald, E L; Dixit, S N; Döppner, T; Edgell, D H; Edwards, M J; Frenje, J; Gatu-Johnson, M; Glebov, V Y; Glenn, S; Glenzer, S H; Grim, G; Haan, S W; Hammel, B A; Hartouni, E P; Hatarik, R; Hatchett, S; Hicks, D G; Hsing, W W; Izumi, N; Jones, O S; Key, M H; Khan, S F; Kilkenny, J D; Kline, J L; Knauer, J; Kyrala, G A; Landen, O L; Le Pape, S; Lindl, J D; Ma, T; MacGowan, B J; Mackinnon, A J; MacPhee, A G; McNaney, J; Meezan, N B; Moody, J D; Moore, A; Moran, M; Moses, E I; Pak, A; Parham, T; Park, H-S; Patel, P K; Petrasso, R; Ralph, J E; Regan, S P; Remington, B A; Robey, H F; Ross, J S; Spears, B K; Springer, P T; Suter, L J; Tommasini, R; Town, R P; Weber, S V; Widmann, K

    2013-11-22

    Radiation-driven, low-adiabat, cryogenic DT layered plastic capsule implosions were carried out on the National Ignition Facility (NIF) to study the sensitivity of performance to peak power and drive duration. An implosion with extended drive and at reduced peak power of 350 TW achieved the highest compression with fuel areal density of ~1.3±0.1 g/cm2, representing a significant step from previously measured ~1.0 g/cm2 toward a goal of 1.5 g/cm2. Future experiments will focus on understanding and mitigating hydrodynamic instabilities and mix, and improving symmetry required to reach the threshold for thermonuclear ignition on NIF. PMID:24313493

  4. Mammographic interpretation training: how useful is handheld technology?

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Gale, Alastair G.; Scott, Hazel

    2008-03-01

    In the UK a national self-assessment scheme (PERFORMS) for mammographers is undertaken as part of the National Health Search Breast Screening Programme. Where appropriate, further training is suggested to improve performance. Ideally, such training would be on-demand; that is whenever and wherever an individual decides to undertake it. To use a portable device for such a purpose would be attractive on many levels. However, it is not known whether handheld technology can be used effectively for viewing mammographic images. Previous studies indicate the potential for viewing medical images with fairly low spatial resolution (e.g. CT, MRI) on PDAs. In this study, we set out to investigate factors that might affect the feasibility of using PDAs as a training technology for examining large, high resolution mammographic images. Two studies are reported: 20 mammographers examined a series of mammograms presented on a PDA, specifying the location of any abnormality. Secondly, a group of technologists examined a series of mammograms presented at different sizes and resolutions to mimic presentation on a PDA and their eye movements were recorded. The results indicate the potential for using PDAs to show such large, high resolution images if suitable Human-computer Interaction (HCI) techniques are employed.

  5. Pulsed photoacoustic flow imaging with a handheld system

    NASA Astrophysics Data System (ADS)

    van den Berg, Pim J.; Daoudi, Khalid; Steenbergen, Wiendelt

    2016-02-01

    Flow imaging is an important technique in a range of disease areas, but estimating low flow speeds, especially near the walls of blood vessels, remains challenging. Pulsed photoacoustic flow imaging can be an alternative since there is little signal contamination from background tissue with photoacoustic imaging. We propose flow imaging using a clinical photoacoustic system that is both handheld and portable. The system integrates a linear array with 7.5 MHz central frequency in combination with a high-repetition-rate diode laser to allow high-speed photoacoustic imaging-ideal for this application. This work shows the flow imaging performance of the system in vitro using microparticles. Both two-dimensional (2-D) flow images and quantitative flow velocities from 12 to 75 mm/s were obtained. In a transparent bulk medium, flow estimation showed standard errors of ˜7% the estimated speed; in the presence of tissue-realistic optical scattering, the error increased to 40% due to limited signal-to-noise ratio. In the future, photoacoustic flow imaging can potentially be performed in vivo using fluorophore-filled vesicles or with an improved setup on whole blood.

  6. Task technical and QA plan: Thermal effects study: To evaluate saltstone properties associated with performance criteria as a function of extended exposure to temperatures typical of adiabatic curing

    SciTech Connect

    Orebaugh, E.G.

    1990-06-15

    The task to evaluate saltstone properties associated with performance criteria as a function of extended exposure to temperatures typical of adiabatic curing is described in this document and involves extension of previous qualification studies for DWPF Saltstone formulations.

  7. Portable Handheld Optical Window Inspection Device

    NASA Technical Reports Server (NTRS)

    Ihlefeld, Curtis; Dokos, Adam; Burns, Bradley

    2010-01-01

    The Portable Handheld Optical Window Inspection Device (PHOWID) is a measurement system for imaging small defects (scratches, pits, micrometeor impacts, and the like) in the field. Designed primarily for window inspection, PHOWID attaches to a smooth surface with suction cups, and raster scans a small area with an optical pen in order to provide a three-dimensional image of the defect. PHOWID consists of a graphical user interface, motor control subsystem, scanning head, and interface electronics, as well as an integrated camera and user display that allows a user to locate minute defects before scanning. Noise levels are on the order of 60 in. (1.5 m). PHOWID allows field measurement of defects that are usually done in the lab. It is small, light, and attaches directly to the test article in any orientation up to vertical. An operator can scan a defect and get useful engineering data in a matter of minutes. There is no need to make a mold impression for later lab analysis.

  8. Use of handheld computers in clinical practice: a systematic review

    PubMed Central

    2014-01-01

    Background Many healthcare professionals use smartphones and tablets to inform patient care. Contemporary research suggests that handheld computers may support aspects of clinical diagnosis and management. This systematic review was designed to synthesise high quality evidence to answer the question; Does healthcare professionals’ use of handheld computers improve their access to information and support clinical decision making at the point of care? Methods A detailed search was conducted using Cochrane, MEDLINE, EMBASE, PsycINFO, Science and Social Science Citation Indices since 2001. Interventions promoting healthcare professionals seeking information or making clinical decisions using handheld computers were included. Classroom learning and the use of laptop computers were excluded. Two authors independently selected studies, assessed quality using the Cochrane Risk of Bias tool and extracted data. High levels of data heterogeneity negated statistical synthesis. Instead, evidence for effectiveness was summarised narratively, according to each study’s aim for assessing the impact of handheld computer use. Results We included seven randomised trials investigating medical or nursing staffs’ use of Personal Digital Assistants. Effectiveness was demonstrated across three distinct functions that emerged from the data: accessing information for clinical knowledge, adherence to guidelines and diagnostic decision making. When healthcare professionals used handheld computers to access clinical information, their knowledge improved significantly more than peers who used paper resources. When clinical guideline recommendations were presented on handheld computers, clinicians made significantly safer prescribing decisions and adhered more closely to recommendations than peers using paper resources. Finally, healthcare professionals made significantly more appropriate diagnostic decisions using clinical decision making tools on handheld computers compared to colleagues

  9. A Data-Driven Design Evaluation Tool for Handheld Device Soft Keyboards

    PubMed Central

    Trudeau, Matthieu B.; Sunderland, Elsie M.; Jindrich, Devin L.; Dennerlein, Jack T.

    2014-01-01

    Thumb interaction is a primary technique used to operate small handheld devices such as smartphones. Despite the different techniques involved in operating a handheld device compared to a personal computer, the keyboard layouts for both devices are similar. A handheld device keyboard that considers the physical capabilities of the thumb may improve user experience. We developed and applied a design evaluation tool for different geometries of the QWERTY keyboard using a performance evaluation model. The model utilizes previously collected data on thumb motor performance and posture for different tap locations and thumb movement directions. We calculated a performance index (PITOT, 0 is worst and 2 is best) for 663 designs consisting in different combinations of three variables: the keyboard's radius of curvature (R) (mm), orientation (O) (°), and vertical location on the screen (L). The current standard keyboard performed poorly (PITOT = 0.28) compared to other designs considered. Keyboard location (L) contributed to the greatest variability in performance out of the three design variables, suggesting that designers should modify this variable first. Performance was greatest for designs in the middle keyboard location. In addition, having a slightly upward curve (R = −20 mm) and orientated perpendicular to the thumb's long axis (O = −20°) improved performance to PITOT = 1.97. Poorest performances were associated with placement of the keyboard's spacebar in the bottom right corner of the screen (e.g., the worst was for R = 20 mm, O = 40°, L =  Bottom (PITOT = 0.09)). While this evaluation tool can be used in the design process as an ergonomic reference to promote user motor performance, other design variables such as visual access and usability still remain unexplored. PMID:25211465

  10. A hand-held electronic tongue based on fluorometry for taste assessment of tea.

    PubMed

    Chang, Kuang-Hua; Chen, Richie L C; Hsieh, Bo-Chuan; Chen, Po-Chung; Hsiao, Hsien-Yi; Nieh, Chi-Hua; Cheng, Tzong-Jih

    2010-12-15

    A hand-held electronic tongue was developed for determining taste levels of astringency and umami in tea infusions. The sensing principles are based on quenching the fluorescence of 3-aminophthalate by tannin, and the fluorogenic reaction of o-phthalaldehyde (OPA) with amino acids to determine astringency and umami levels, respectively. Both reactions were measured by a single fluorescence sensing system with same excitation and emission wavelengths (340/425 nm). This work describes in detail the design, fabrication, and performance evaluation of a hand-held fluorometer with an ultra-violet light emitted diode (UVLED) and a photo-detector with a filter built-in. The dimension and the weight of proposed electronic tongue prototype are only 120×60×65 mm(3) and 150 g, respectively. The detection limits of this prototype for theanine and tannic acid were 0.2 μg/ml and 1 μg/ml, respectively. Correlation coefficients of this prototype compared with a commercial fluorescence instrument are both higher than 0.995 in determinations of tannin acid and theanine. Linear detection ranges of the hand-held fluorometer for tannic acid and theanine are 1-20 μg/ml and 0.2-10 μg/ml (CV<5%, n=3), respectively. A specified taste indicator for tea, defined as ratio of umami to astringency, was adopted here to effectively distinguish flavour quality of partially fermented Oolong teas. PMID:20728331

  11. Manipulator Design and Operation for a Six-Degree-of-Freedom Handheld Tremor-Canceling Microsurgical Instrument

    PubMed Central

    Yang, Sungwook; MacLachlan, Robert A.; Riviere, Cameron N.

    2014-01-01

    This paper presents the design and actuation of a six-degree-of-freedom (6-DOF) manipulator for a handheld instrument, known as “Micron,” which performs active tremor compensation during microsurgery. The design incorporates a Gough-Stewart platform based on piezoelectric linear motor, with a specified minimum workspace of a cylinder 4 mm long and 4 mm in diameter at the end-effector. Given the stall force of the motors and the loading typically encountered in vitreoretinal microsurgery, the dimensions of the manipulator are optimized to tolerate a transverse load of 0.2 N on a remote center of motion near the midpoint of the tool shaft. The optimization yields a base diameter of 23 mm and a height of 37 mm. The fully handheld instrument includes a custom-built optical tracking system for control feedback, and an ergonomic housing to serve as a handle. The manipulation performance was investigated in both clamped and handheld conditions. In positioning experiments with varying side loads, the manipulator tolerates side load up to 0.25 N while tracking a sinusoidal target trajectory with less than 20 μm error. Physiological hand tremor is reduced by about 90% in a pointing task, and error less than 25 μm is achieved in handheld circle-tracing. PMID:25419103

  12. Manipulator Design and Operation for a Six-Degree-of-Freedom Handheld Tremor-Canceling Microsurgical Instrument.

    PubMed

    Yang, Sungwook; MacLachlan, Robert A; Riviere, Cameron N

    2015-04-01

    This paper presents the design and actuation of a six-degree-of-freedom (6-DOF) manipulator for a handheld instrument, known as "Micron," which performs active tremor compensation during microsurgery. The design incorporates a Gough-Stewart platform based on piezoelectric linear motor, with a specified minimum workspace of a cylinder 4 mm long and 4 mm in diameter at the end-effector. Given the stall force of the motors and the loading typically encountered in vitreoretinal microsurgery, the dimensions of the manipulator are optimized to tolerate a transverse load of 0.2 N on a remote center of motion near the midpoint of the tool shaft. The optimization yields a base diameter of 23 mm and a height of 37 mm. The fully handheld instrument includes a custom-built optical tracking system for control feedback, and an ergonomic housing to serve as a handle. The manipulation performance was investigated in both clamped and handheld conditions. In positioning experiments with varying side loads, the manipulator tolerates side load up to 0.25 N while tracking a sinusoidal target trajectory with less than 20 μm error. Physiological hand tremor is reduced by about 90% in a pointing task, and error less than 25 μm is achieved in handheld circle-tracing. PMID:25419103

  13. Portable multiwavelength laser diode source for handheld photoacoustic devices

    NASA Astrophysics Data System (ADS)

    Canal, Celine; Laugustin, Arnaud; Kohl, Andreas; Rabot, Olivier

    2016-04-01

    The ageing population faces today an increase of chronic diseases such as rheumatism/arthritis, cancer and cardio vascular diseases for which appropriate treatments based on a diagnosis at an early-stage of the disease are required. Some imaging techniques are already available in order to get structural information. Within the non-invasive group, ultrasound images are common in these fields of medicine. However, there is a need for a point-of-care device for imaging smaller structures such as blood vessels that cannot be observed with purely ultrasound based devices. Photoacoustics proved to be an attractive candidate. This novel imaging technique combines pulsed laser light for excitation of tissues and an ultrasound transducer as a receptor. Introduction of this technique into the clinic requires to drastically shrink the size and cost of the expensive and bulky nanosecond lasers generally used for light emission. In that context, demonstration of ultra-short pulse emission with highly efficient laser diodes in the near-infrared range has been performed by Quantel, France. A multi-wavelength laser source as small as a hand emitted more than 1 mJ per wavelength with four different wavelengths available in pulses of about 90 ns. Such a laser source can be integrated into high sensitivity photoacoustic handheld systems due to their outstanding electrical-to-optical efficiency of about 25 %. Further work continues to decrease the pulse length as low as 40 ns while increasing the pulse energy to 2 mJ.

  14. Military forensic use of handheld 3D camera

    NASA Astrophysics Data System (ADS)

    Larsson, Hâkan; Letalick, Dietmar

    2013-05-01

    One of the main threats for armed forces in conflict areas are attacks by improvised explosive devices (IED). After an IED attack a forensic investigation of the site is undertaken. In many ways military forensic work is similar to the civilian counterpart. There are the same needs to acquire evidence in the crime scene, such as fingerprints, DNA, and samples of the remains of the IED. Photos have to be taken and the geometry of the location shall be measured, preferably in 3D. A main difference between the military and the civilian forensic work is the time slot available for the scene investigation. The military must work under the threat of fire assault, e.g. snipers. The short time slot puts great demands on the forensic team and the equipment they use. We have done performance measurements of the Mantis-Vision F5 sensor and evaluated the usefulness in military forensic applications. This paper will describe some applications and show possibilities and also limitations of using a handheld laser imaging sensor for military forensic investigations.

  15. Bone age maturity assessment using hand-held device

    NASA Astrophysics Data System (ADS)

    Ratib, Osman M.; Gilsanz, Vicente; Liu, Xiaodong; Boechat, M. I.

    2004-04-01

    Purpose: Assessment of bone maturity is traditionally performed through visual comparison of hand and wrist radiograph with existing reference images in textbooks. Our goal was to develop a digital index based on idealized hand Xray images that can be incorporated in a hand held computer and used for visual assessment of bone age for patients. Material and methods: Due to the large variability in bone maturation in normals, we generated a set of "ideal" images obtained by computer combinations of images from our normal reference data sets. Software for hand-held PDA devices was developed for easy navigation through the set of images and visual selection of matching images. A formula based on our statistical analysis provides the standard deviation from normal based on the chronological age of the patient. The accuracy of the program was compared to traditional interpretation by two radiologists in a double blind reading of 200 normal Caucasian children (100 boys, 100 girls). Results: Strong correlations were present between chronological age and bone age (r > 0.9) with no statistical difference between the digital and traditional assessment methods. Determinations of carpal bone maturity in adolescents was slightly more accurate using the digital system. The users did praise the convenience and effectiveness of the digital Palm Index in clinical practice. Conclusion: An idealized digital Palm Bone Age Index provides a convenient and effective alternative to conventional atlases for the assessment of skeletal maturity.

  16. A simple handheld pupillometer for chromatic Flicker studies

    NASA Astrophysics Data System (ADS)

    Bernabei, M.; Tinarelli, R.; Peretto, L.; Rovati, L.

    2014-02-01

    A portable pupillometer has been developed which is capable of performing accurate measurements of the pupil diameter during chromatic flicker stimulations. The handheld measuring system records the near-infrared image of the pupil at the rate of 25 fps and simultaneously stimulates the eye using a diffused flicker light generated by light emitting diodes (LEDs). Intensity, frequency and chromatic coordinates of the stimulus can be easily adjusted using a user-friendly graphical interface. Thanks to a chromatic monitoring of the stimulus close to the plane of the eye, photopically matched conditions can be easily achieved. The pupil diameter/area can be measured during flickering stimuli that are generated with frequency in a range of 0.1-20 Hz. The electronic unit, properly connected to the personal computer through a USB port, drives the optical unit, which can be easily held in a hand. The software interface controlling the system was developed in LabVIEW. This paper describes the instrument optical setup, front-end electronics and data processing. Moreover preliminary results obtained on a voluntary are reported.

  17. MEMS-Based Handheld Fourier Domain Doppler Optical Coherence Tomography for Intraoperative Microvascular Anastomosis Imaging

    PubMed Central

    Huang, Yong; Furtmüller, Georg J.; Tong, Dedi; Zhu, Shan; Lee, W. P. Andrew; Brandacher, Gerald; Kang, Jin U.

    2014-01-01

    Purpose To demonstrate the feasibility of a miniature handheld optical coherence tomography (OCT) imager for real time intraoperative vascular patency evaluation in the setting of super-microsurgical vessel anastomosis. Methods A novel handheld imager Fourier domain Doppler optical coherence tomography based on a 1.3-µm central wavelength swept source for extravascular imaging was developed. The imager was minimized through the adoption of a 2.4-mm diameter microelectromechanical systems (MEMS) scanning mirror, additionally a 12.7-mm diameter lens system was designed and combined with the MEMS mirror to achieve a small form factor that optimize functionality as a handheld extravascular OCT imager. To evaluate in-vivo applicability, super-microsurgical vessel anastomosis was performed in a mouse femoral vessel cut and repair model employing conventional interrupted suture technique as well as a novel non-suture cuff technique. Vascular anastomosis patency after clinically successful repair was evaluated using the novel handheld OCT imager. Results With an adjustable lateral image field of view up to 1.5 mm by 1.5 mm, high-resolution simultaneous structural and flow imaging of the blood vessels were successfully acquired for BALB/C mouse after orthotopic hind limb transplantation using a non-suture cuff technique and BALB/C mouse after femoral artery anastomosis using a suture technique. We experimentally quantify the axial and lateral resolution of the OCT to be 12.6 µm in air and 17.5 µm respectively. The OCT has a sensitivity of 84 dB and sensitivity roll-off of 5.7 dB/mm over an imaging range of 5 mm. Imaging with a frame rate of 36 Hz for an image size of 1000(lateral)×512(axial) pixels using a 50,000 A-lines per second swept source was achieved. Quantitative vessel lumen patency, lumen narrowing and thrombosis analysis were performed based on acquired structure and Doppler images. Conclusions A miniature handheld OCT imager that can be used for

  18. Ultra-compact switchable SLO/OCT handheld probe design

    NASA Astrophysics Data System (ADS)

    LaRocca, Francesco; Nankivil, Derek; DuBose, Theodore; Farsiu, Sina; Izatt, Joseph A.

    2015-03-01

    Handheld scanning laser ophthalmoscopy (SLO) and optical coherence tomography (OCT) systems facilitate imaging of young children and subjects that have difficulty fixating. More compact and lightweight probes allow for better portability and increased comfort for the operator of the handheld probe. We describe a very compact, novel SLO and OCT handheld probe design. A single 2D microelectromechanical systems (MEMS) scanner and a custom optical design using a converging beam prior to the scanner permitted significant reduction in the system size. Our design utilized a combination of commercial and custom optics that were optimized in Zemax to achieve near diffraction-limited resolution of 8 μm over a 7° field of view. The handheld probe has a form factor of 7 x 6 x 2.5 cm and a weight of only 94 g, which is over an order of magnitude lighter than prior SLO-OCT handheld probes. Images were acquired from a normal subject with an incident power on the eye under the ANSI limit. With this device, which is the world's lightest and smallest SLO-OCT system, we were able to visualize parafoveal cone photoreceptors and nerve fiber bundles without the use of adaptive optics.

  19. High frequency performance extending to millimeter-waves in inverted-microstrip-line-type LC phase shifter

    NASA Astrophysics Data System (ADS)

    Nose, T.; Ito, Y.; Iisaka, Takuya; Chien, L.-C.; Catanescu, O.; Golvin, A.; Isota, Y.; Sasamori, T.; Ito, R.; Honma, M.

    2013-03-01

    Various liquid crystal (LC) phase shifters that operate in the super-high-frequency electromagnetic-wave regions have been investigated using planar-type excellent waveguides such as the microstrip line (MSL) and coplanar waveguide (CPW). First planar-type LC phase shifters were constructed using MSL, which was developed as an excellent planar waveguide for super-high-frequency electromagnetic waves. CPW-type LC phase shifters have attracted continued attention, because when they are used, all the signal and ground electrodes are at the same surface, which leads to ease in integration for constructing various functional devices. However, they suffer from an essential drawback of degradation in the phase shift magnitude, which is because the propagating electromagnetic waves encounter the permittivity of both the substrate and the LC materials, which reduces the modulation effect of the LC materials to less than half. In this work, a novel MSL-type LC phase shifter is investigated to achieve excellent phase shifting performance while maintaining ease in integration, as offered by the CPW-type phase shifter. Several device structural parameters are investigated to improve the transmission and phase shifting properties. Some LC materials are also tested for further improvement in the high-frequency operation extended to the millimeter-wave region.

  20. Extended Time on Academic Assignments: Does Increased Time Lead to Improved Performance for Children with Attention-Deficit/Hyperactivity Disorder?

    ERIC Educational Resources Information Center

    Pariseau, Meaghan E.; Fabiano, Gregory A.; Massetti, Greta M.; Hart, Katie C.; Pelham, William E., Jr.

    2010-01-01

    Researchers examined the impact of an extended time accommodation on appropriate classroom behavior and rate of work completion for 33 children with attention-deficit/hyperactivity disorder (ADHD). Participants received standard (30 min) or extended (45 min) time to complete seatwork in a within-subject, crossover design study. Appropriate…

  1. Effects of Extended Time Allotments on Reading Comprehension Performance of College Students with and without Learning Disabilities

    ERIC Educational Resources Information Center

    Lewandowski, Lawrence; Cohen, Justin; Lovett, Benjamin J.

    2013-01-01

    Students with disabilities often receive test accommodations in schools and on high-stakes tests. Students with learning disabilities (LD) represent the largest disability group in schools, and extended time the most common test accommodation requested by such students. This pairing persists despite controversy over the validity of extended time…

  2. A wireless handheld probe with spectrally constrained evolution strategies for diffuse optical imaging of tissue

    PubMed Central

    Flexman, M. L.; Kim, H. K.; Stoll, R.; Khalil, M. A.; Fong, C. J.; Hielscher, A. H.

    2012-01-01

    We present a low-cost, portable, wireless diffuse optical imaging device. The handheld device is fast, portable, and can be applied to a wide range of both static and dynamic imaging applications including breast cancer, functional brain imaging, and peripheral artery disease. The continuous-wave probe has four near-infrared wavelengths and uses digital detection techniques to perform measurements at 2.3 Hz. Using a multispectral evolution algorithm for chromophore reconstruction, we can measure absolute oxygenated and deoxygenated hemoglobin concentration as well as scattering in tissue. Performance of the device is demonstrated using a series of liquid phantoms comprised of Intralipid®, ink, and dye. PMID:22462907

  3. Comparison of a MEMS-Based Handheld OCT Scanner With a Commercial Desktop OCT System for Retinal Evaluation

    PubMed Central

    Sayegh, Samir I.; Nolan, Ryan M.; Jung, Woonggyu; Kim, Jeehyun; McCormick, Daniel T.; Chaney, Eric J.; Stewart, Charles N.; Boppart, Stephen A.

    2014-01-01

    Purpose The goal of this study was to evaluate the ability of our handheld optical coherence tomography (OCT) scanner to image the posterior and anterior structures of the human eye, and especially the individual layers of the retina, and to compare its diagnostic performance with that of a fixed desktop commercial ophthalmic OCT system. Methods We compared the clinical imaging results of our handheld OCT with a leading commercial desktop ophthalmic system (RTVue) used in specialist offices. Six patients exhibiting diabetes-related retinal pathology had both eyes imaged with each OCT system. Results In both sets of images, the structural irregularities of the retinal layers could be identified such as retinal edema and vitreomacular traction. Conclusions Our handheld OCT system can be used to identify relevant anatomical structures and pathologies in the eye, potentially enabling earlier screening, disease detection, and treatment. Images can be acquired quickly, with sufficient resolution and negligible motion artifacts that would normally limit its diagnostic use. Translational Relevance Following screening and early disease detection in primary care via our optimized handheld OCT system, patients can be referred to a specialist for treatment, preventing further disease progression. While many primary care physicians are adept at using the ophthalmoscope, they can definitely take advantage of more advanced technologies. PMID:25068092

  4. A case of recurrent, self-inflicted handheld laser retinopathy.

    PubMed

    Simonett, Joseph M; Scarinci, Fabio; Labriola, Leanne T; Jampol, Lee M; Goldstein, Debra A; Fawzi, Amani A

    2016-04-01

    A 17-year-old young man presented with vision loss and discrete, bilateral foveal lesions. The patient returned 6 weeks later with worsening vision, prominent bilateral retinal lesions, and a full-thickness macular hole in the right eye consistent with recurrent self-inflicted handheld laser retinopathy. After instructing the family to remove the patient's access to laser pointers, follow-up examination revealed spontaneous closure of the macular hole but minimal vision improvement. Recurrent ocular exposure to handheld lasers can masquerade as an organic process in patients who withhold pertinent history. Clinicians should rely on the distinguishing features seen on examination and multimodal imaging to make the diagnosis of handheld laser retinopathy. PMID:27012364

  5. 77 FR 32996 - Certain Handheld Electronic Computing Devices, Related Software, and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-04

    ... Microsoft Corporation (``Microsoft'') of Redmond, Washington. 76 FR 22918. The complaint, as amended... COMMISSION Certain Handheld Electronic Computing Devices, Related Software, and Components Thereof... importation of certain handheld electronic computing devices, related software, and components thereof...

  6. In vivo melanoma depth detection by a handheld photoacoustic microscope

    NASA Astrophysics Data System (ADS)

    Zhou, Yong; Xing, Wenxin; Maslov, Konstantin I.; Cornelius, Lynn A.; Wang, Lihong V.

    2015-03-01

    We developed a handheld photoacoustic microscope (PAM) to detect melanoma and determine tumor depth in nude mice in vivo. Compared to our previous PAM system for melanoma imaging, a new light delivery mechanism is introduced to improve light penetration. We show that melanomas with 4.1 mm and 3.3 mm thicknesses can be successfully detected in phantom and in vivo experiments, respectively. With its deep melanoma imaging ability and novel handheld design, this system is promising for clinical melanoma diagnosis, prognosis, and surgical planning for patients at the bedside.

  7. Improved biological phosphorus removal performance driven by the aerobic/extended-idle regime with propionate as the sole carbon source.

    PubMed

    Wang, Dongbo; Li, Xiaoming; Yang, Qi; Zheng, Wei; Wu, Yan; Zeng, Tianjing; Zeng, Guangming

    2012-08-01

    Our previous studies proved that biological phosphorus removal (BPR) could be achieved in an aerobic/extended-idle (AEI) process employing two typical substrates of glucose and acetate as the carbon sources. This paper further evaluated the feasibility of another important substrate, propionate, serving as the carbon source for BPR in the AEI process, and compared the BPR performance between the AEI and anaerobic/oxic (A/O) processes. Two sequencing batch reactors (SBRs) were operated, respectively, as the AEI and A/O regimes for BPR using propionate as the sole substrate. The results showed that the AEI-reactor removed 2.98 ± 0.04-4.06 ± 0.06 mg of phosphorus per g of total suspended solids during the course of the steady operational trial, and the phosphorus content of the dried sludge was reached 8.0 ± 0.4% after 56-day operation, demonstrating the good performance of phosphorus removal. Then, the efficiencies of BPR and the transformations of the intracellular storages were compared between two SBRs. It was observed that the phosphorus removal efficiency was maintained around 95% in the AEI-reactor, and about 83% in the A/O-reactor, although the latter showed much greater transformations of both polyhydroxyalkanoates and glycogen. The facts clearly showed that BPR could be enhanced by the AEI regime using propionate as the carbon source. Finally, the mechanisms for the propionate fed AEI-reactor improving BPR were investigated. It was found that the sludge cultured by the AEI regime had more polyphosphate containing cells than that by the A/O regime. Further investigation revealed that the residual nitrate generated in the last aerobic period was readily deteriorated BPR in the A/O-SBR, but a slight deterioration was observed in the AEI-SBR. Moreover, the lower glycogen transformation measured in the AEI-SBR indicated that the biomass cultured by the AEI regime contained less glycogen accumulating organisms activities than that by the A/O regime. PMID

  8. Innovation and Integration: Case Studies of Effective Teacher Practices in the Use of Handheld Computers

    ERIC Educational Resources Information Center

    Chavez, Raymond Anthony

    2010-01-01

    Previous research conducted on the use of handheld computers in K-12 education has focused on how handheld computer use affects student motivation, engagement, and productivity. These four case studies sought to identify effective teacher practices in the integration of handhelds into the curriculum and the factors that affect those practices. The…

  9. 30 CFR 77.402 - Hand-held power tools; safety devices.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held power tools; safety devices. 77.402... COAL MINES Safeguards for Mechanical Equipment § 77.402 Hand-held power tools; safety devices. Hand-held power tools shall be equipped with controls requiring constant hand or finger pressure to...

  10. 30 CFR 75.1724 - Hand-held power tools; safety devices.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held power tools; safety devices. 75.1724... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1724 Hand-held power tools; safety devices. Hand-held power tools shall be equipped with controls requiring...