Formation of fast-spreading lower oceanic crust as revealed by a new Mg-REE coupled geospeedometer

NASA Astrophysics Data System (ADS)

Sun, Chenguang; Lissenberg, C. Johan

2018-04-01

A new geospeedometer is developed based on the differential closures of Mg and rare earth element (REE) bulk-diffusion between coexisting plagioclase and clinopyroxene. By coupling the two elements with distinct bulk closure temperatures, this speedometer can numerically solve the initial temperatures and cooling rates for individual rock samples. As the existing Mg-exchange thermometer was calibrated for a narrow temperature range and strongly relies on model-dependent silica activities, a new thermometer is developed using literature experimental data. When the bulk closure temperatures of Mg and REE are determined, respectively, using this new Mg-exchange thermometer and the existing REE-exchange thermometer, this speedometer can be implemented for a wide range of compositions, mineral modes, and grain sizes. Applications of this new geospeedometer to oceanic gabbros from the fast-spreading East Pacific Rise at Hess Deep reveal that the lower oceanic crust crystallized at temperatures of 998-1353 °C with cooling rates of 0.003-10.2 °C/yr. Stratigraphic variations of the cooling rates and crystallization temperatures support deep hydrothermal circulations and in situ solidification of various replenished magma bodies. Together with existing petrological, geochemical and geophysical evidence, results from this new speedometry suggest that the lower crust formation at fast-spreading mid-ocean ridges involves emplacement of primary mantle melts in the deep section of the crystal mush zone coupled with efficient heat removal by crustal-scale hydrothermal circulations. The replenished melts become chemically and thermally evolved, accumulate as small magma bodies at various depths, feed the shallow axial magma chamber, and may also escape from the mush zone to generate off-axial magma lenses.

VizieR Online Data Catalog: RVs and R-band obs. of the EB* V541 Cyg (Torres+, 2017)

NASA Astrophysics Data System (ADS)

Torres, G.; McGruder, C. D.; Siverd, R. J.; Rodriguez, J. E.; Pepper, J.; Stevens, D. J.; Stassun, K. G.; Lund, M. B.; James, D.

2017-10-01

V541 Cyg was observed spectroscopically at the Harvard-Smithsonian Center for Astrophysics (CfA) with the Digital Speedometer (DS) on the 1.5m Tillinghast reflector at the Fred L. Whipple Observatory on Mount Hopkins (AZ). We gathered 72 exposures between 2000 July and 2004 October (R~35000). Observations of V541 Cyg were obtained between 2007 May and 2014 November in the course of the Kilodegree Extremely Little Telescope transiting planet program (KELT). The passband of these observations resembles that of a very broad R-band filter. The magnitudes given in tables 2 and 3 are instrumental (not referring to a standard photometric system). (3 data files).

A simple wave driver

NASA Astrophysics Data System (ADS)

Kağan Temiz, Burak; Yavuz, Ahmet

2015-08-01

This study was done to develop a simple and inexpensive wave driver that can be used in experiments on string waves. The wave driver was made using a battery-operated toy car, and the apparatus can be used to produce string waves at a fixed frequency. The working principle of the apparatus is as follows: shortly after the car is turned on, the wheel starts to turn at a constant angular speed. A rod that is fixed on the wheel turns at the same constant angular speed, too. A tight string that the wave will be created on is placed at a distance where the rod can touch the string. During each rotation of the wheel, the rod vibrates the string up and down. The vibration frequency of this rod equals the wheel’s rotation frequency, and this frequency value can be measured easily with a small magnet and a bicycle speedometer. In this way, the frequency of the waves formed in the rope can also be measured.

VizieR Online Data Catalog: Accurate astrometry & RVs of 4 multiple systems (Tokovinin+, 2017)

NASA Astrophysics Data System (ADS)

Tokovinin, A.; Latham, D. W.

2017-10-01

The outer subsystems are classical visual binaries. Historic micrometric measurements and modern speckle interferometric data have been obtained from the WDS database on our request. Additionally, we secured new speckle astrometry and relative photometry of two systems at the 4.1m SOAR telescope. Published radial velocities (RVs) are used here together with the new data. The RVs were measured with the CfA Digital Speedometers, initially using the 1.5m Wyeth Reflector at the Oak Ridge Observatory in the town of Harvard, Massachusetts, and subsequently with the 1.5m Tillinghast Reflector at the Whipple Observatory on Mount Hopkins, Arizona. Starting in 2009, the new fiber-fed Tillinghast Reflector Echelle Spectrograph (TRES) was used. The spectral resolution was 44000 for all three spectrographs. Two objects, HIP 101955 and 103987, were observed in 2015 with the CHIRON echelle spectrograph at the 1.5m telescope at CTIO with a spectral resolution of 80000. (4 data files).

A cycle timer for testing electric vehicles

NASA Technical Reports Server (NTRS)

Soltis, R. F.

1978-01-01

A cycle timer was developed to assist the driver of an electric vehicle in more accurately following and repeating SAE driving schedules. These schedules require operating an electric vehicle in a selected stop-and-go driving cycle and repeating this cycle pattern until the vehicle ceases to meet the requirements of the cycle. The heart of the system is a programmable read-only memory (PROM) that has the required test profiles permanently recorded on plug-in cards, one card for each different driving schedule. The PROM generates a direct current analog signal that drives a speedometer displayed on one scale of a dual movement meter. The second scale of the dual movement meter displays the actual speed of the vehicle as recorded by the fifth wheel. The vehicle operator controls vehicle speed to match the desired profile speed. The PROM controls the recycle start time as well as the buzzer activation. The cycle programmer is powered by the test vehicle's 12-volt accessory battery, through a 5-volt regulator and a 12-volt dc-to-dc converter.

Towards a centralized Grid Speedometer

NASA Astrophysics Data System (ADS)

Dzhunov, I.; Andreeva, J.; Fajardo, E.; Gutsche, O.; Luyckx, S.; Saiz, P.

2014-06-01

Given the distributed nature of the Worldwide LHC Computing Grid and the way CPU resources are pledged and shared around the globe, Virtual Organizations (VOs) face the challenge of monitoring the use of these resources. For CMS and the operation of centralized workflows, the monitoring of how many production jobs are running and pending in the Glidein WMS production pools is very important. The Dashboard Site Status Board (SSB) provides a very flexible framework to collect, aggregate and visualize data. The CMS production monitoring team uses the SSB to define the metrics that have to be monitored and the alarms that have to be raised. During the integration of CMS production monitoring into the SSB, several enhancements to the core functionality of the SSB were required; They were implemented in a generic way, so that other VOs using the SSB can exploit them. Alongside these enhancements, there were a number of changes to the core of the SSB framework. This paper presents the details of the implementation and the advantages for current and future usage of the new features in SSB.

Dashboard Videos

NASA Astrophysics Data System (ADS)

Gleue, Alan D.; Depcik, Chris; Peltier, Ted

2012-11-01

Last school year, I had a web link emailed to me entitled "A Dashboard Physics Lesson." The link, created and posted by Dale Basier on his Lab Out Loud blog, illustrates video of a car's speedometer synchronized with video of the road. These two separate video streams are compiled into one video that students can watch and analyze. After seeing this website and video, I decided to create my own dashboard videos to show to my high school physics students. I have produced and synchronized 12 separate dashboard videos, each about 10 minutes in length, driving around the city of Lawrence, KS, and Douglas County, and posted them to a website.2 Each video reflects different types of driving: both positive and negative accelerations and constant speeds. As shown in Fig. 1, I was able to capture speed, distance, and miles per gallon from my dashboard instrumentation. By linking this with a stopwatch, each of these quantities can be graphed with respect to time. I anticipate and hope that teachers will find these useful in their own classrooms, i.e., having physics students watch the videos and create their own motion maps (distance-time, speed-time) for study.

The Unseen Companion of HD 114762

NASA Astrophysics Data System (ADS)

Latham, David W.

2014-01-01

I have told the story of the discovery of the unseen companion of HD114762 (Latham et al. 1989, Nature, 389, 38-40) in a recent publication (Latham 2012, New Astronomy Reviews 56, 16-18). The discovery was enabled by a happy combination of some thinking outside the box by Tsevi Mazeh at Tel Aviv University and the development of new technology for measuring stellar spectra at the Harvard-Smithsonian Center for Astrophysics. Tsevi's unconventional idea was that giant exoplanets might be found much closer to their host stars than Jupiter and Saturn are to the Sun, well inside the snow line. Our instrument was a high-resolution echelle spectrograph optimized for measuring radial velocities of stars similar to the Sun. The key technological developments were an intensified Reticon photon-counting detector under computer control combined with sophisticated analysis of the digital spectra. The detector signal-processing electronics eliminated persistence, which had plagued other intensified systems. This allowed bright Th-Ar calibration exposures before and after every stellar observation, which in turn enabled careful correction for spectrograph drifts. We built three of these systems for telescopes in Massachusetts and Arizona and christened them the "CfA Digital Speedometers". The discovery of HD 114762-b was serendipitous, but not accidental.

Young swimmers' classification based on kinematics, hydrodynamics, and anthropometrics.

PubMed

Barbosa, Tiago M; Morais, Jorge E; Costa, Mário J; Goncalves, José; Marinho, Daniel A; Silva, António J

2014-04-01

The aim of this article has been to classify swimmers based on kinematics, hydrodynamics, and anthropometrics. Sixty-seven young swimmers made a maximal 25 m front-crawl to measure with a speedometer the swimming velocity (v), speed-fluctuation (dv) and dv normalized to v (dv/v). Another two 25 m bouts with and without carrying a perturbation device were made to estimate active drag coefficient (CDa). Trunk transverse surface area (S) was measured with photogrammetric technique on land and in the hydrodynamic position. Cluster 1 was related to swimmers with a high speed fluctuation (ie, dv and dv/v), cluster 2 with anthropometrics (ie, S) and cluster 3 with a high hydrodynamic profile (ie, CDa). The variable that seems to discriminate better the clusters was the dv/v (F=53.680; P<.001), followed by the dv (F=28.506; P<.001), CDa (F=21.025; P<.001), S (F=6.297; P<.01) and v (F=5.375; P=.01). Stepwise discriminant analysis extracted 2 functions: Function 1 was mainly defined by dv/v and S (74.3% of variance), whereas function 2 was mainly defined by CDa (25.7% of variance). It can be concluded that kinematics, hydrodynamics and anthropometrics are determinant domains in which to classify and characterize young swimmers' profiles.

Heart Rate Monitors

NASA Technical Reports Server (NTRS)

1990-01-01

Under a NASA grant, Dr. Robert M. Davis and Dr. William M. Portnoy came up with a new type of electrocardiographic electrode that would enable long term use on astronauts. Their invention was an insulated capacitive electrode constructed of a thin dielectric film. NASA subsequently licensed the electrode technology to Richard Charnitski, inventor of the VersaClimber, who founded Heart Rate, Inc., to further develop and manufacture personal heart monitors and to produce exercise machines using the technology for the physical fitness, medical and home markets. Same technology is on both the Home and Institutional Model VersaClimbers. On the Home Model an infrared heart beat transmitter is worn under exercise clothing. Transmitted heart rate is used to control the work intensity on the VersaClimber using the heart rate as the speedometer of the exercise. This offers advantages to a full range of users from the cardiac rehab patient to the high level physical conditioning of elite athletes. The company manufactures and markets five models of the 1*2*3 HEART RATE monitors that are used wherever people exercise to accurately monitor their heart rate. Company is developing a talking heart rate monitor that works with portable headset radios. A version of the heart beat transmitter will be available to the manufacturers of other aerobic exercise machines.

VizieR Online Data Catalog: The G+M eclipsing binary V530 Orionis photometry (Torres+, 2014)

NASA Astrophysics Data System (ADS)

Torres, G.; Lacy, C. H. S.; Pavlovski, K.; Feiden, G. A.; Sabby, J. A.; Bruntt, H.; Clausen, J. V.

2017-08-01

V530 Ori was monitored spectroscopically with three different instruments over a period of more than 17 yr. Observations began at the Harvard-Smithsonian Center for Astrophysics (CfA) in 1996 June with a Cassegrain-mounted echelle spectrograph ("Digital Speedometer", DS; Latham 1992ASPC...32..110L) attached to the 1.5 m Tillinghast reflector at the F. L. Whipple Observatory (Mount Hopkins, AZ). We gathered a further 30 spectra of V530 Ori at the Kitt Peak National Observatory (KPNO) from 1999 March to 2001 January, using the coude-feed telescope and the coude spectrometer. Finally, 41 additional observations were obtained at the CfA from 2009 November to 2014 March with the Tillinghast Reflector Echelle Spectrograph (TRES; Furesz 2008, PhD thesis , Univ. Szeged, Hungary) on the 1.5 m telescope mentioned earlier. Two sets of V-band images of V530 Ori were obtained with independent robotic telescopes operating at the University of Arkansas (URSA WebScope) and near Silver City, NM (NFO WebScope) from 2001 January to 2012 February. Differential photometric measurements of V530 Ori were also gathered with the Stromgren Automatic Telescope at ESO (La Silla, Chile), during several campaigns from 2001 January to 2006 February. (5 data files).

VizieR Online Data Catalog: Radial velocities in M67. I. 1278 candidate members (Geller+, 2015)

NASA Astrophysics Data System (ADS)

Geller, A. M.; Latham, D. W.; Mathieu, R. D.

2015-10-01

This is the first in a series of papers studying the dynamical state of the old open cluster M67 through precise radial velocities. This is also the paper LXVII of the WIYN Open Cluster Study. Our radial velocity survey of M67 began as part of the dissertation work of Mathieu (1983PhDT.........8M), taking advantage of the CfA Digital Speedometers (DS). Three nearly identical instruments were used, initially on the MMT (from HJD2445337 to HJD2450830) and 1.5m Tillinghast Reflector (from HJD2444184 to HJD2454958) at the Fred Lawrence Whipple Observatory on Mount Hopins, Arizona, and then later on the 1.5m Wyeth Reflector (from HJD2445722 to HJD2453433) at the Oak Ridge Observatory in the Town of Harvard, Massachusetts. Subsequently the M67 target samples were expanded several times. Radial velocities measurements from other programs were integrated into the database, and our observational facilities were extended to include Hydra Multi-Object Spectrograph (MOS) at the WIYN Observatory (from HJD2453386 to HJD2456709) and the new Tillinghast Reflector Echelle Spectrograph (TRES) on the Tillinghast Reflector (from HJD2455143 to HJD2456801). Details about the telescopes, observing procedures, and data reductions of spectra obtained with the CfA DS can be found in Latham (1985srv..conf...21L, 1992ASPC...32..110L). The corresponding information for spectra obtained with Hydra at the WIYN Observatory can be found in Geller et al. 2008 (cat. J/AJ/135/2264), Geller et al. 2010 (cat. J/AJ/139/1383) and Hole et al. (2009). TRES is a stabilized fiber-fed echelle spectrograph with a CCD detector and resolution of 44000. The initial CfA sample was defined in 1982. The last surviving CfA Digital Speedometer, on the 1.5m Tillinghast Reflector, was retired in the summer of 2009. Over the following five observing seasons, TRES was used to continue the radial velocity observations of targets (mostly binaries) from both the CfA and the WIYN samples. Importantly, Roger Griffin and James Gunn also had a radial velocity program for M67 from 1971 to 1982 at the Palomar Hale 5m telescope (from HJD2440952 to HJD2445297), which they supplemented with contemporaneous observations obtained with the CORAVEL instrument (from HJD2444340 to HJD2446413) at Haute Provence for five of the binaries. Their target sample was very similar to our initial sample. We refer to the target stars and the measurements taken at all telescope/instrument pairs except WIYN/Hydra as the CfA sample and data. As of 2015 February, there are 447 stars in the CfA sample. WIYN observations of M67 began on 2005 January 15 as part of the WIYN Open Cluster Study (WOCS; Mathieu, 2000ASPC..198..517M). In total there are 1278 stars within the WIYN stellar sample; 382 of these stars are also in the CfA stellar sample. (1 data file).

Young drivers' perception of adult and child pedestrians in potential street-crossing situations.

PubMed

Ābele, Līva; Haustein, Sonja; Møller, Mette

2018-04-03

Despite overall improvements in road traffic safety, pedestrian accidents continue to be a serious public health problem. Due to lack of experience, limited cognitive and motoric skills, and smaller size, children have a higher injury risk as pedestrians than adults. To what extent drivers adjust their driving behaviour to children's higher vulnerability is largely unknown. To determine whether young male drivers' behaviour and scanning pattern differs when approaching a child and an adult pedestrian in a potential street-crossing situation, sixty-five young (18-24) male drivers' speed, lateral position and eye movements were recorded in a driving simulator. Results showed that fewer drivers responded by slowing down and that drivers had a higher driving speed when approaching a child pedestrian, although the time of the first fixation on both types of pedestrians was the same. However, drivers drove farther away from a child than an adult pedestrian. Additionally, fewer drivers who did not slow down fixated on the speedometer while approaching the child pedestrian. The results show that young drivers behave differently when approaching a child and an adult pedestrian, though not in a way that appropriately accounts for the limitations of a child pedestrian. A better understanding of how drivers respond to different types of pedestrians and why could contribute to the development of pedestrian detection and emergency braking systems. Copyright © 2018 Elsevier Ltd. All rights reserved.

An experimental evaluation of patient decision aid design to communicate the effects of medications on the rate of progression of structural joint damage in rheumatoid arthritis.

PubMed

Martin, Richard W; Brower, Matthew E; Geralds, Alexander; Gallagher, Patience J; Tellinghuisen, Donald J

2012-03-01

To explore how effectively information presentation formats used in a patient decision aid communicated the ability of a disease modifying anti-rheumatic drug to slow the rate of progression of rheumatoid arthritis related structural joint damage (SJD). 91 first year psychology students and 91 RA patients participated in a prospective randomized, single blind, factorial experimental design evaluating the effect of four information formats on: satisfaction with risk communication, verbatim and gist recall of a hypothetical anti-rheumatic drug's ability to slow the rate of progression of SJD. Both groups underestimated the hypothetical drug's ability to slow SJD. Formats that supported the narrative statement with a reinforcing graphic element resulted in recall closer to the true value. Comparison of the results from testing of RA patients and college students were remarkably similar across formats. Rate of progression as communicated by narrative statement plus a graphic element (i.e. speedometer metaphor or pictograph) aided recall better than a narrative statement alone. Our results suggest that testing decision aid components with non-patients may provide data generalizable to patient populations. Graphics must be used carefully in patient decision aids as they can enhance recall, but may also introduce unintended recall bias. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Galileo on Two Wheels: Why Does Newton Make Me Keep Pedaling This Thing?

NASA Astrophysics Data System (ADS)

Gardner, Dave; Osenbach, Kate; Connolly, Joseph

2010-02-01

As part of an effort to use examples for the bicycle to illustrate basic physics principles, we have been exploring the application of Newton's laws of motion to a moving bicycle. In particular, we have developed methods to measure the bicycle's two primary forces of resistance-tire rolling resistance and air resistance on rider and bike. With the use of minimal equipment such as stopwatches and bicycle speedometers, we have obtained data that provide a very good fit to simple models and closed differential equation solutions. We have also found that the bicycle affords a simple, low tech, and convenient method to study concepts of terminal velocity and rolling resistance. Just as Galileo made use of inclined planes to study falling objects, we used gently sloping hills to determine forces on the moving bicycle. Our methods make use of a novel technique to determine the bicycle and rider frontal cross sectional area. We hope our methods and results will be of interest to students of physics and mathematics and to the general cycling community. We have found it is possible for a cyclist to easily measure; without the use of expensive time in a wind tunnel; the effects of various body positions on wind resistance. This paper also examines the force and power consequences of riding at high speeds. )

Concurrent audio-visual feedback for supporting drivers at intersections: A study using two linked driving simulators.

PubMed

Houtenbos, M; de Winter, J C F; Hale, A R; Wieringa, P A; Hagenzieker, M P

2017-04-01

A large portion of road traffic crashes occur at intersections for the reason that drivers lack necessary visual information. This research examined the effects of an audio-visual display that provides real-time sonification and visualization of the speed and direction of another car approaching the crossroads on an intersecting road. The location of red blinking lights (left vs. right on the speedometer) and the lateral input direction of beeps (left vs. right ear in headphones) corresponded to the direction from where the other car approached, and the blink and beep rates were a function of the approaching car's speed. Two driving simulators were linked so that the participant and the experimenter drove in the same virtual world. Participants (N = 25) completed four sessions (two with the audio-visual display on, two with the audio-visual display off), each session consisting of 22 intersections at which the experimenter approached from the left or right and either maintained speed or slowed down. Compared to driving with the display off, the audio-visual display resulted in enhanced traffic efficiency (i.e., greater mean speed, less coasting) while not compromising safety (i.e., the time gap between the two vehicles was equivalent). A post-experiment questionnaire showed that the beeps were regarded as more useful than the lights. It is argued that the audio-visual display is a promising means of supporting drivers until fully automated driving is technically feasible. Copyright © 2016. Published by Elsevier Ltd.

The role of uncertainty and reward on eye movements in a virtual driving task

PubMed Central

Sullivan, Brian T.; Johnson, Leif; Rothkopf, Constantin A.; Ballard, Dana; Hayhoe, Mary

2012-01-01

Eye movements during natural tasks are well coordinated with ongoing task demands and many variables could influence gaze strategies. Sprague and Ballard (2003) proposed a gaze-scheduling model that uses a utility-weighted uncertainty metric to prioritize fixations on task-relevant objects and predicted that human gaze should be influenced by both reward structure and task-relevant uncertainties. To test this conjecture, we tracked the eye movements of participants in a simulated driving task where uncertainty and implicit reward (via task priority) were varied. Participants were instructed to simultaneously perform a Follow Task where they followed a lead car at a specific distance and a Speed Task where they drove at an exact speed. We varied implicit reward by instructing the participants to emphasize one task over the other and varied uncertainty in the Speed Task with the presence or absence of uniform noise added to the car's velocity. Subjects' gaze data were classified for the image content near fixation and segmented into looks. Gaze measures, including look proportion, duration and interlook interval, showed that drivers more closely monitor the speedometer if it had a high level of uncertainty, but only if it was also associated with high task priority or implicit reward. The interaction observed appears to be an example of a simple mechanism whereby the reduction of visual uncertainty is gated by behavioral relevance. This lends qualitative support for the primary variables controlling gaze allocation proposed in the Sprague and Ballard model. PMID:23262151

Effects of age and illumination on night driving: a road test.

PubMed

Owens, D Alfred; Wood, Joanne M; Owens, Justin M

2007-12-01

This study investigated the effects of drivers' age and low light on speed, lane keeping, and visual recognition of typical roadway stimuli. Poor visibility, which is exacerbated by age-related changes in vision, is a leading contributor to fatal nighttime crashes. There is little evidence, however, concerning the extent to which drivers recognize and compensate for their visual limitations at night. Young, middle-aged, and elder participants drove on a closed road course in day and night conditions at a "comfortable" speed without speedometer information. During night tests, headlight intensity was varied over a range of 1.5 log units using neutral density filters. Average speed and recognition of road signs decreased significantly as functions of increased age and reduced illumination. Recognition of pedestrians at night was significantly enhanced by retroreflective markings of limb joints as compared with markings of the torso, and this benefit was greater for middle-aged and elder drivers. Lane keeping showed nonlinear effects of lighting, which interacted with task conditions and drivers' lateral bias, indicating that older drivers drove more cautiously in low light. Consistent with the hypothesis that drivers misjudge their visual abilities at night, participants of all age groups failed to compensate fully for diminished visual recognition abilities in low light, although older drivers behaved more cautiously than the younger groups. These findings highlight the importance of educating all road users about the limitations of night vision and provide new evidence that retroreflective markings of the limbs can be of great benefit to pedestrians' safety at night.

Metrology - Beyond the Calibration Lab

NASA Technical Reports Server (NTRS)

Mimbs, Scott M.

2008-01-01

We rely on data from measurements every day; a gas-pump, a speedometer, and a supermarket weight scale are just three examples of measurements we use to make decisions. We generally accept the data from these measurements as "valid." One reason we can accept the data is the "legal metrology" requirements established and regulated by the government in matters of commerce. The measurement data used by NASA, other government agencies, and industry can be critical to decisions which affect everything from economic viability, to mission success, to the security of the nation. Measurement data can even affect life and death decisions. Metrology requirements must adequately provide for risks associated with these decisions. To do this, metrology must be integrated into all aspects of an industry including research, design, testing, and product acceptance. Metrology, the science of measurement, has traditionally focused on the calibration of instruments, and although instrument calibration is vital, it is only a part of the process that assures quality in measurement data. For example, measurements made in research can influence the fundamental premises that establish the design parameters, which then flow down to the manufacturing processes, and eventually impact the final product. Because a breakdown can occur anywhere within this cycle, measurement quality assurance has to be integrated into every part of the life-cycle process starting with the basic research and ending with the final product inspection process. The purpose of this paper is to discuss the role of metrology in the various phases of a product's life-cycle. For simplicity, the cycle will be divided in four broad phases, with discussions centering on metrology within NASA. .

Structure, function, and cortical representation of the rat submandibular whisker trident.

PubMed

Thé, Lydia; Wallace, Michael L; Chen, Christopher H; Chorev, Edith; Brecht, Michael

2013-03-13

Although the neurobiology of rodent facial whiskers has been studied intensively, little is known about sensing in other vibrissae. Here we describe the under-investigated submandibular "whisker trident" on the rat's chin. In this three-whisker array, a unique unpaired midline whisker is laterally flanked by two slightly shorter whiskers. All three whiskers point to the ground and are curved backwards. Unlike other whiskers, the trident is not located on an exposed body part. Trident vibrissae are not whisked and do not touch anything over long stretches of time. However, trident whiskers engage in sustained ground contact during head-down running while the animal is exploring or foraging. In biomechanical experiments, trident whiskers follow caudal ground movement more smoothly than facial whiskers. Remarkably, deflection angles decrease with increasing ground velocity. We identified one putative trident barrel in the left somatosensory cortex and two barrels in the right somatosensory cortex. The elongated putative trident-midline barrel is the longest and largest whisker barrel, suggesting that the midline trident whisker is of great functional significance. Cortical postsynaptic air-puff responses in the trident representation show much less temporal precision than facial whisker responses. Trident whiskers do not provide as much high-resolution information about object contacts as facial whiskers. Instead, our observations suggest an idiothetic function: their biomechanics allow trident whiskers to derive continuous measurements about ego motion from ground contacts. The midline position offers unique advantages in sensing heading direction in a laterally symmetric manner. The changes in trident deflection angle with velocity suggest that trident whiskers might function as a tactile speedometer.

Plantar pressure of clipless and toe-clipped pedals in cyclists - A pilot study

PubMed Central

Davis, Andrea; Pemberton, Troy; Ghosh, Subhajit; Maffulli, Nicola; Padhiar, Nat

2011-01-01

Summary To determine the effect of clipless and toe-clipped pedals on plantar foot pressure while cycling. Seven bikers and 11 healthy volunteers were tested on a Giant ATX Team mountain bike, Tekscan Clinical 5.24 F-scan® system with an inner sole pressure sensor, a Tacx Cycle force One Turbo Trainer and a Cateye Mity 8 computerized speedometer were used. The subjects wore Shimano M037 shoes and used a standard clipless and toe-clipped pedal. The seat height was set at 100% of subject’s trochanteric height. Plantar pressures were recorded over 12 consecutive crank cycles at a constant speed for each of the power outputs. The videos were analysed to record the pressure exerted at 12 positions on the foot for each variable. Whether there is any dominance of any of the metatarsals, and any difference in plantar pressures between clipped and clipless pedal. There was a significant difference in the pressure at many positions of the foot, but the sites were different for each individual. General regression analysis indicated that pedal type had a statistically significant effect on plantar pressure at the sites of 1st metatarsal (p=0.042), 3rd metatarsal (p<0.001), 5th metatarsal (<0.001), 2nd (p=0.018) and 5th toe (p<0.001), lateral midfoot (p<0.001) and central heel (p<0.001) areas. Clipless pedals produce higher pressures which are more spread across the foot than toe-clipped pedals. This may have implications for their use in the prevention and/or management of overuse injuries in the knee and foot. PMID:23738240

Phosphorus as indicator of magmatic olivine residence time, morphology and growth rate

NASA Astrophysics Data System (ADS)

Sobolev, Alexander; Batanova, Valentina

2015-04-01

Phosphorus is among of slowest elements by diffusion rate in silicate melts and crystals (e.g. Spandler et al, 2007). In the same time it is moderately incompatible to compatible with olivine (Brunet & Chazot, 2001; Grant & Kohn, 2013). This makes phosphorus valuable tracer of olivine crystallization in natural conditions. Indeed, it is shown that natural magmatic olivine crystals commonly posses strong and complicated zoning in phosphorus (Milman-Barris et al, 2008; Welsch et al, 2014). In this paper we intend to review phosphorus behavior in olivine in published experimental and natural olivine studies and present large set of new EPMA data on phosphorus zoning in olivine phenocrysts from MORBs, OIBs, komatiites and kimberlites. We will show that sharp olivine zones enriched in phosphorus by a factor of 10-20 over prediction by equilibrium partition may be due to formation of P-rich boundary layer on the interface of fast growing olivine. This is proved by finding of small-size (normally 10 mkm or less) exceptionally P-rich melt inclusions in olivine, which are otherwise similar in composition to typical melt. These observations could provide potential olivine growth speedometer. We will also demonstrate, that sharp zoning in phosphorus may provide valuable information on the residence time of olivine crystals in different environments: magma chambers and conduits as well as mantle sources. This study has been founded by Russian Science Foundation grant 14-17-00491. References: Spandler, et al, 2007, Nature, v. 447, p. 303-306; Brunet & Chazot, 2001, Chemical Geology, v. 176, p. 51-72; Grant & Kohn, 2013, American Mineralogist, v. 98, p. 1860-1869; Milman-Barris et al, 2008, Contr. Min. Petrol. v. 155, p.739-765; Welsch et al, 2014, Geology, v. 42, p.867-870.

Coupled CaAl-NaSi diffusion in plagioclase feldspar: Experiments and applications to cooling rate speedometry

NASA Astrophysics Data System (ADS)

Grove, Timothy L.; Baker, Michael B.; Kinzler, Rosamond J.

1984-10-01

The rate of CaAl-NaSi interdiffusion in plagioclase feldspar was determined under 1 atm anhydrous conditions over the temperature range 1400° to 1000°C in calcic plagioclase (An 80-81) by homogenizing coherent exsolution lamellae. The dependence of the average interdiffusion coefficient on temperature is given by the expression: D˜ = 10.99 ( cm 2/sec) exp (-123.4( kcal/mol)/RT), (T in °K). This value is for diffusion perpendicular to the (03 1¯) interface of the lamellae. CaAl-NaSi interdiffusion is 4 to 5 orders of magnitude slower than oxygen diffusion in the temperature range 1400° to 1200°C and possibly 10 orders of magnitude slower at subsolidus temperatures. The large differences in diffusion rates explain the apparent contradiction posed by the plagioclases of large layered intrusions ( e.g., the Skaergaard), which retain delicate Ca, Na compositional zoning profiles on the micron scale, but have undergone complete oxygen isotopic exchange with heated meteoric groundwater from the surrounding wall rocks. CaAl-NaSi diffusion is slow, the closure temperature is high (within the solidus-liquidus interval), and Ca-Na zoning is preserved. Oxygen diffusion is faster, the closure temperature is lower (350°-400°C) and the feldspars exchange oxygen with the low-temperature hydrothermal fluids. The complex micron-scale oscillatory zones in plagioclase can also be used as cooling rate speedometers for volcanic and plutonic plagioclase. Cooling histories typical of large mafic intrusions ( e.g. the Stillwater) are slow, begin at high initial temperatures (1200°C) and result in homogenization of oscillatory zones on the scale of 10 microns. The oscillatory zones found in the plagioclase of granodioritic plutons are preserved because cooling is initiated at a lower temperature (1000°C) limiting diffusion to submicron length scales despite the slow cooling rate of the intrusion.

H Diffusion in Olivine and Pyroxene from Peridotite Xenoliths and a Hawaiian Magma Speedometer

NASA Technical Reports Server (NTRS)

Peslier, A. H.; Bizimis, M.

2014-01-01

Hydrogen is present as a trace element in olivine and pyroxene and its content distribution in the mantle results from melting and metasomatic processes. Here we examine how these H contents can be disturbed during decompression. Hydrogen was analyzed by FTIR in olivine and pyroxene of spinel peridotite xenoliths from Salt Lake Crater (SLC) nephelinites which are part of the rejuvenated volcanism at Oahu (Hawaii) [1,2]. H mobility in pyroxene resulting from spinel exsolution during mantle upwelling Most pyroxenes in SLC peridotites exhibit exsolutions, characterized by spinel inclusions. Pyroxene edges where no exsolution are present have less H then their core near the spinel. Given that H does not enter spinel [3], subsolidus requilibration may have concentrated H in the pyroxene adjacent to the spinel exsolution during mantle upwelling. H diffusion in olivine during xenolith transport by its host magma and host magma ascent rates Olivines have lower water contents at the edge and near fractures compared to at their core, while the concentrations of all other chemical elements appear homogeneous. This suggests that some of the initial water has diffused out of the olivine. Water loss from the olivine is thought to occur during host-magma ascent and xenolith transport to the surface [4-6]. Diffusion modeling matches best the data when the initial water content used is that measured at the core of the olivines, implying that mantle water contents are preserved at the core of the olivines. The 3225 cm(sup -1) OH band at times varies independantly of other OH bands, suggesting uneven H distribution in olivine defects likely acquired during mantle metasomatism just prior to eruption and unequilibrated. Diffusion times (1-48 hrs) combined with depths of peridotite equilibration or of magma start of degassing allow to calculate ascent rates for the host nephelinite of 0.1 to 27 m/s.

Panoramic Epipolar Image Generation for Mobile Mapping System

NASA Astrophysics Data System (ADS)

Chen, T.; Yamamoto, K.; Chhatkuli, S.; Shimamura, H.

2012-07-01

The notable improvements on performance and low cost of digital cameras and GPS/IMU devices have caused MMSs (Mobile Mapping Systems) to be gradually becoming one of the most important devices for mapping highway and railway networks, generating and updating road navigation data and constructing urban 3D models over the last 20 years. Moreover, the demands for large scale visual street-level image database construction by the internet giants such as Google and Microsoft have made the further rapid development of this technology. As one of the most important sensors, the omni-directional cameras are being commonly utilized on many MMSs to collect panoramic images for 3D close range photogrammetry and fusion with 3D laser point clouds since these cameras could record much visual information of the real environment in one image at field view angle of 360° in longitude direction and 180° in latitude direction. This paper addresses the problem of panoramic epipolar image generation for 3D modelling and mapping by stereoscopic viewing. These panoramic images are captured with Point Grey's Ladybug3 mounted on the top of Mitsubishi MMS-X 220 at 2m intervals along the streets in urban environment. Onboard GPS/IMU, speedometer and post sequence image analysis technology such as bundle adjustment provided high accuracy position and attitude data for these panoramic images and laser data, this makes it possible to construct the epipolar geometric relationship between any two adjacent panoramic images and then the panoramic epipolar images could be generated. Three kinds of projection planes: sphere, cylinder and flat plane are selected as the epipolar images' planes. In final we select the flat plane and use its effective parts (middle parts of base line's two sides) for epipolar image generation. The corresponding geometric relations and results will be presented in this paper.

VizieR Online Data Catalog: Photometry and spectroscopy of V501 Mon (Torres+, 2015)

NASA Astrophysics Data System (ADS)

Torres, G.; Lacy, C. H. S.; Pavlovski, K.; Fekel, F. C.; Muterspaugh, M. W.

2016-06-01

Spectroscopic observations of V501 Mon were carried out with three different instruments. They began at the Harvard-Smithsonian Center for Astrophysics (CfA) in 2005 November, using the now decommissioned Digital Speedometer (DS) mounted on the 1.5m Tillinghast reflector at the Fred L. Whipple Observatory on Mount Hopkins (AZ). Seven spectra were recorded through 2009 March with an intensified photon-counting Reticon detector, and cover a narrow span of 45Å centered at 5190Å (MgIb triplet). The resolving power of this instrument was R~35000, and the signal-to-noise ratios of the spectra range from 13 to 22 per resolution element of 8.5km/s. Thirty seven additional spectra were gathered from 2009 November to 2015 February with the Tillinghast Reflector Echelle Spectrograph (TRES) on the same telescope. This bench-mounted, fiber-fed instrument provides a resolving power of R~44000 in 51 orders over the wavelength span 3900-9100Å. The signal-to-noise ratios of the 37 spectra range from 8 to 56 per resolution element of 6.8km/s. The heliocentric velocities we obtained from the DS and TRES spectra are listed in Table2. Between 2011 October and 2015 February we also obtained 57 usable spectra of V501 Mon with the Tennessee State University 2m Automatic Spectroscopic Telescope (AST) and a fiber-fed echelle spectrograph at Fairborn Observatory in southeast Arizona. The detector for these observations was a Fairchild 486 CCD, with 15μm pixels in a 4096*4096 format. The spectrograms have 48 orders ranging from 3800 to 8260Å. Because of the faintness of V501 Mon (V=12.32), we used a fiber that produced a spectral resolution of 0.4Å, corresponding to a resolving power of 15000 at 6000Å. Our spectra have typical signal-to-noise ratios per resolution element of 40 at 6000Å. We list the final values in Table3. An extensive program of CCD photometry was carried out using the NFO WebScope ear Silver City, New Mexico, for the purpose of gathering an accurate V-band light curve of V501 Mon for analysis. A total of 6729 images were obtained over 281 nights between 2005 January and February. Table5 lists these differential photometric measurements. Measurements of the times of eclipse for V501 Mon collected from the literature are listed in Table1, and cover approximately seven decades. Abundances for individual elements are listed in Table7. (5 data files).

LAVIA--an evaluation of the potential safety benefits of the French intelligent speed adaptation project.

PubMed

Driscoll, R; Page, Y; Lassarre, S; Ehrlich, J

2007-01-01

This paper presents the potential safety benefits of the experimental French LAVIA Intelligent Speed Adaptation system, according to road network and system mode, based on observed driving speeds, distributions of crash severity and crash injury risk. Results are given for car frontal and side impacts that together, represent 80% of all serious and fatal injuries in France. Of the three system modes tested (advisory, driver select, mandatory), our results suggest that driver select would most significantly reduce serious injuries and death. We estimate this 100% utilization of cars equipped with this type of speed adaptation system would decrease injury rates by 6% to 16% over existing conditions depending on the type of crash (frontal or side) and road environment considered. Some limitations associated with the analysis are also identified. LAVIA is the acronym for Limiteur s'Adaptant à la VItesse Autorisée, a French Intelligent Speed Adaptation (ISA) project that was set up towards the end of 1999. At the time, 1998 French national road safety statistics recorded 8437 road related deaths, a figure which had shown virtually no positive evolution since 1994. Detailed analysis of the contributory factors involved in fatal road crashes highlighted the time-honoured crash and injury causation mechanisms - alcohol, speed and seatbelts. Of the three, excessive speed (over and above the posted speed limit) was a contributory factor in half of all fatal crashes Inappropriate behaviour such as excessive speeding can be dealt with either by legislative or driver-incentive programmes. The first of these two solutions involves the introduction of new legislation and/or the enforcement of existing laws. This is the domain of Public Authorities and will not be discussed in detail here. Alternatively, incentive schemes can involve the implementation of speed related driver assistance systems, categorised according to their voluntary or mandatory character and the degree of autonomy proposed to or imposed on the driver. The LAVIA project set out to address several possible combinations of these two factors. The generic term Intelligent Speed Adaptation (ISA) encompasses a wide range of different technologies aimed at improving road safety by reducing traffic speed and homogenising traffic flow, within the limit of posted speed limits. "Fixed speed limit" systems inform the vehicle of the posted speed limit whereas "variable speed limit" systems take into account certain locations on the road network where a speed below the posted limit is desirable, such as sharp curves, pedestrian crossings or crash black spots. Taken one step further, speed limit systems may also take into account weather and traffic flow conditions. These systems are known as "dynamic speed limit" systems and benefit from real time updates for a specific location. The different ISA systems are generally characterised by the degree of freedom of choice given to the driver in moderating his or her speed. Speed limit technologies may be advisory (informing drivers of the current speed limit and speed limit changes), voluntary (allowing the driver to decide whether or not to implement speed limitation) or mandatory (imposing the current speed limit). The information supplied may be provided by way of the road infrastructure (and associated equipment), may be acquired autonomously by the vehicle or may be based on an interaction between the infrastructure and the vehicle. Even the most basic of these systems should be considered as a very useful driver aid, helping the driver to stay within the posted speed limit, avoiding "unnecessary" speeding fines through inattention, modelling driver behaviour through the long term reduction of speeds and reducing driver workload by limiting visual speedometer controls. Vehicle-based ISA systems should not be confused with internal systems. These latter systems rely upon the driver entering the desired travel speed, which is then maintained by cruise control or set as a maximum value by automatic speed regulators. Although these systems will not be discussed in detail here, it should be noted that the engine management technologies that they employ are a vital component of ISA systems.

The approaches for the decision support in case natural hazards

NASA Astrophysics Data System (ADS)

Vyazilov, Evgeny; Chunyaev, Nikita

2013-04-01

In spite of using highly automated systems of measurement, collecting, storing, handling, prediction and delivery of information on the marine environment, including natural hazards, the amount of damage from natural phenomena increases. Because information on the marine environment delivered to the industrial facilities not effectively used. To such information pays little attention by individual decision-makers and not always perform preventive measures necessary for reduce and prevent damage. Automation of information support will improve the efficiency management of the marine activities. In Russia develops "The Unified system of the information about World ocean" (ESIMO, http://esimo.ru/), that integrates observation, analysis, prognostic and climate data. Necessary to create tools to automatic selection natural disasters through all integrated data; notification decision-makers about arising natural hazards - software agent; provision of information in a compact form for the decision-makers; assessment of possible damage and costs to the preventive measures; providing information on the impacts of environment on economic facilities and recommendations for decision-making; the use of maps, diagrams, tables for reporting. Tools for automatic selection designed for identification of natural phenomena based on the resources ESIMO and corresponding critical values of the indicators environment. The result of this module will be constantly updated database of critical situations of environment for each object or technological process. To operational notify and provide current information about natural hazards proposes using a software agent that is installed on the computer decision-makers, which is activated in case critical situations and provides a minimum of information. In the event of natural disaster software agent should be able to inform decision-makers about this, providing information on the current situation, and the possibility for more and detailed information about natural hazard. Software agent must be able to be configured by the user to a specific object: a specific station or a drilling rigs that region or area, regardless of the size of the object. And depending on the selected settings and parameters it needs to apply the values of critical indexes. There is a need for real-time display hydrometeorological information with compact scheme that reflects the environment indicators that affect industrial facility in the form of devices (thermometer, aneroid, footstock, speedometer, hygrometer, thermograph, barograph, rain gauge, wind vane, etc.) with the ability to display indicators exceed a critical value. This scheme is designed to provide maximum information in the shortest possible time reference that provides an intuitive interface (display by generally accepted standardized instruments). Analytical services ESIMO combined with geographic information service provides information about area or point to decision-makers of showing the dynamics of changes of parameters in the form of graphics, diagrams, maps, tables. If the data sources are updated, analytical services automatically provides the relevance of the data in the analytical views of the complex. Analytical services works with database of integrated data and used for the preparation and presentation of the consumers of the federal and regional level for the analysis of information on the World Oceans. The analytic services show a set of indicators about the situation in the World Ocean. The complex provides the processing, analysis of qualitative and quantitative characteristics (indexes) of the marine environment and maritime activities of the Russian Federation. To assess the need for preventive measures, decision-makers require information in the form of potential economic consequences of natural hazard, cost of preventive measures to prevent damage. We can use for that the economic and mathematical models. When making the decision decision-makers must understand the possible consequences of natural phenomena and rely on the advice that they receive from a decision support system. Such information about the impacts and recommendations are based on the knowledge base (rules of "if, then"), formed on the basis of experience gained in the past. This should take into account not only the critical values for each object and technological process, but also the type of information (observations, forecasting, climate, and after the phenomenon), the level of decision-making, the season of the year, the climate zone where the object is located. Within ESIMO created integrated database that containing the results of the monitoring of the marine environment. The database includes the observation, analysis, and forecasting and climate data. Operational data is updated automatically at specified intervals of a few minutes to a week, depending on the frequency of observations. Climatic data is updated as needed, for example, once a year or once every five years. Integrated database contains a set of indicators related to a specific object, and to a certain geographic area, according to the observations made and the data entered data. In addition to hydrometeorological parameters database contains socio-economic information. At present, was created the database of critical values and information about the impacts of and recommendations for the 30 natural hazards, developed the data structure and software is under development. The interaction of all components of an information support will reduce the economic damage from natural disaster on individual objects economy (ships, ports, etc.) and improve public safety through more prompt delivery of information to decision-makers and the public, besides receive more informative data (district with symptoms natural phenomena , assessment of possible damage, the impact of and recommendations).