Science.gov

Sample records for periscopes

  1. Steerable zoom periscope

    NASA Astrophysics Data System (ADS)

    Lidwell, Michael O.

    1995-10-01

    Submarine periscopes often provide a field change mechanism but there is a distinct preference for fixed magnifications for immediate awareness of range. However for a variety of reasons, the standard periscope is being succeeded by television. Even high definition TV is restricted in displayed resolution points compared with a direct vision periscope, therefore as apparent size is now dependent on the display, a continuous zoom is suggested to ensure relevance of the captured image. The need for steering and stabilization of the sight line and viewing through a window, within the bounds of an unobtrusive and seaworthy package present special optical problems. A stable entrance pupil must be projected onto the window beyond the line of sight prism. It follows that the optical system incorporates a relay stage to provide a real aperture stop and that configuration changes on both sides of the intermediate image are necessary to control the entrance pupil. Compact zoom lenses are usually based on Galilean telescopes and the moving group diverging; in contrast this zoom periscope is based on the Kepler type and all the lens groups are converging. The system provides an 8:1 zoom range, is unconstrained in overall length but fits a standard 6 multiplied by 40 ocular within a tube of 50 mm in diameter. A disadvantage is the motion of moving lens groups through a focus with a risk of blemishes becoming visible but the image quality is hardly inferior to a traditional layout using interchangeable lenses.

  2. 30. DETAIL OF PERISCOPE SHOWING EYEPIECE AND FINE FOCUS ON ...

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

    30. DETAIL OF PERISCOPE SHOWING EYEPIECE AND FINE FOCUS ON LEFT; CONTROL HANDLES IN CENTER; WHEEL FOR ROTATING PERISCOPE AT BOTTOM - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  3. 29. VIEW OF 1959 KOLLMORGEN BUNKER PERISCOPE LOCATED IN NORTHEAST ...

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

    29. VIEW OF 1959 KOLLMORGEN BUNKER PERISCOPE LOCATED IN NORTHEAST CORNER OF SLC-3W CONTROL ROOM. NOTE SCHRADER VALVE ABOVE HANDLE ON RIGHT SIDE OF PERISCOPE. MONITOR LABELED '1-FLAMEBUCKET' IN BACKGROUND TO LEFT OF PERISCOPE. DIGITAL COUNTDOWN AND HOLD CLOCKS IMMEDIATELY ABOVE MONITOR. ANOTHER DIGITAL COUNTDOWN CLOCK AND THE MILITARY TIME CLOCK ON NORTH WALL BENEATH THE MONITOR. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. PERISCOPE POP-IN BEAM MONITOR.

    SciTech Connect

    JOHNSON,E.D.

    1998-05-07

    We have built monitors for use as beam diagnostics in the narrow gap of an undulator for an FEL experiment. They utilize an intercepting screen of doped YAG scintillating crystal to make light that is imaged through a periscope by conventional video equipment. The absolute position can be ascertained by comparing the electron beam position with the position of a He:Ne laser that is observed by this pop-in monitor. The optical properties of the periscope and the mechanical arrangement of the system mean that beam can be spatially determined to the resolution of the camera, in this case approximately 10 micrometers. Our experience with these monitors suggests improvements for successor designs, which we also describe.

  5. Periscope pop-in beam monitor

    SciTech Connect

    Johnson, E.D.; Graves, W.S.; Robinson, K.E.

    1998-06-01

    The authors have built monitors for use as beam diagnostics in the narrow gap of an undulator for an FEL experiment. They utilize an intercepting screen of doped YAG scintillating crystal to make light that is imaged through a periscope by conventional video equipment. The absolute position can be ascertained by comparing the electron beam position with the position of a He:Ne laser that is observed by this pop-in monitor. The optical properties of the periscope and the mechanical arrangement of the system mean that beam can be spatially determined to the resolution of the camera, in this case approximately 10 micrometers. The experience with these monitors suggests improvements for successor designs, which they also describe.

  6. 32. DETAIL OF PRESSURE GAUGE INSTALLED ON BUNKER PERISCOPE IN ...

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

    32. DETAIL OF PRESSURE GAUGE INSTALLED ON BUNKER PERISCOPE IN 1991 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. IET. Periscope shielding and installation details. Shows range of scanning ...

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

    IET. Periscope shielding and installation details. Shows range of scanning head, removable concrete cap, concrete shielding. Ralph M. Parsons 902-4-ANP-620-A 324. Date: February 1954. Approved by INEEL Classification Office for public release. INEEL Index code no. 035-0620-00-693-106909 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  8. Resolving Spectral Lines with a Periscope-Type DVD Spectroscope

    ERIC Educational Resources Information Center

    Wakabayashi, Fumitaka

    2008-01-01

    A new type of DVD spectroscope, the periscope type, is described and the numerical analysis of the observed emission and absorption spectra is demonstrated. A small and thin mirror is put inside and an eighth part of a DVD is used as a grating. Using this improved DVD spectroscope, one can observe and photograph visible spectra more easily and…

  9. Periscope: Looking into learning in best-practices physics classrooms

    NASA Astrophysics Data System (ADS)

    Scherr, Rachel

    2014-03-01

    Periscope is a set of materials to support university instructors in observing, discussing, and reflecting on best practices in university instruction. Periscope is organized into short ``video workshops,'' each introducing a significant topic in the teaching and learning of physics, such as formative assessment or cooperative learning. The workshops are appropriate for university professors, two-year college faculty, graduate student teaching assistants, and undergraduate learning assistants. Key topics in teaching and learning are introduced through captioned video episodes of introductory physics students in the classroom, chosen to prompt collaborative discussion. Video episodes from exemplary sites (including the University of Maryland, University of Colorado - Boulder, Harvard University, and Florida International University) showcase a variety of research-tested instructional formats such as Peer Instruction and Tutorials in Introductory Physics. Discussion questions prompt participants who view the episode to reflect on their pedagogical beliefs, on their own practice, and on the results of physics education research. Periscope materials may be flexibly adapted for settings ranging from brief introductory sessions to all-day workshops or weekly meetings.

  10. Symmetric periscope for concentric beam configuration in an ultra-high precision laser interferometric beam launcher

    NASA Technical Reports Server (NTRS)

    Ames, Lawrence L. (Inventor)

    2006-01-01

    An optical component especially suited for common path heterodyne interferometry comprises a symmetric dual-periscope configuration. Each periscope is substantially identical to the other with regard to certain design aspects. The resulting design is an optical component that is highly stable with variations in temperature and angular deviations.

  11. IET control building (TAN620). remains of periscope connections and control ...

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

    IET control building (TAN-620). remains of periscope connections and control console at far west wall of control room. facing westerly. INEEL negative no. HD-21-2-2 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  12. 31. DETAIL OF MANUFACTURER'S PLATE ON BUNKER PERISCOPE IN SLC3W ...

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

    31. DETAIL OF MANUFACTURER'S PLATE ON BUNKER PERISCOPE IN SLC-3W CONTROL ROOM - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  13. NIF Periscope Wall Modal Study Comparison of Results for 2 FEA Models with 2 Modal Tests

    SciTech Connect

    Eli, M W; Gerhard, M A; Lee, C L; Sommer, S C; Woehrle, T G

    2000-10-26

    This report summarizes experimentally and numerically determined modal properties for one of the reinforced concrete end walls of the NIF Periscope Support Structure in Laser Bay 1. Two methods were used to determine these modal properties: (1) Computational finite-element analyses (modal extraction process); and (2) Experimental modal analysis based on measured test data. This report also includes experimentally determined modal properties for a prototype LM3/Polarizer line-replaceable unit (LRU) and a prototype PEPC LRU. Two important parameters, used during the design phase, are validated through testing [ref 1]. These parameters are the natural frequencies and modal damping (of the system in question) for the first several global modes of vibration. Experimental modal testing provides these modal values, along with the corresponding mode shapes. Another important parameter, the input excitation (expected during normal operation of the NIF laser system) [ref 1], can be verified by performing a series of ambient vibration measurements in the vicinity of the particular system (or subsystem) of interest. The topic of ambient input excitation will be covered in a separate report. Due to the large mass of the Periscope Pedestal, it is difficult to excite the entire series of Periscope Pedestal Walls all at once. It was decided that the experimental modal tests would be performed on just one Periscope End Wall in Laser Bay 1. Experimental modal properties for the Periscope End Wall have been used to validate and update the FE analyses. Results from the analyses and modal tests support the conclusion that the Periscope Pedestal will not exceed the stability budget, which is described in reference 1. The results of the modal tests for the Periscope End Wall in Laser Bay 1 have provided examples of modal properties that can be derived from future modal tests of the entire Periscope Assembly (excluding the LRU's). This next series of larger modal tests can be performed

  14. Inertial Stabilization Of Periscopic Sights Band Driven Three Axle Gimbal

    NASA Astrophysics Data System (ADS)

    Ellison, Bruce; Richi, James

    1983-10-01

    There are many applications for the use of optical instruments in vehicles, especially in the military. It is required that these instruments function while the vehicle is on the move, in rough terrain. Angular distrubances of the line-of-sight pointing vector can render these instruments useless as observation or pointing devices, due to image blurring. Instruments that must retain resolution in this environment are usually stabilized by means of gimbals. If the entire instrument (such as a large television camera) is to be stabilized, the problem becomes one of a simple stable platform, or, a single axle gimbal. If, however, the instrument is hard mounted to the vehicle and the image is instead to be stabilized by means of a compensating optical component, such as a periscope head mirror, the problem is a little more complex. In a periscopic sight the head mirror must be driven at half-speed to the line-of-sight disturbance to compensate for the angle doubling effect of the mirror. That is, in order to stabilize the line-of-sight, the mirror cannot be inertiallv stable, but must be coupled to a stable mass at a ratio of 1:2. In many applications it is necessary to transmit the elevation angle of the line-of-sight to a fire control system, or, to direct the lines-of-sight of other platforms. In order to do this, transducers are mounted on the "drive axle", (gyros, synchros, tachometers, potentiometers, motors), which detect and trasmit the angular position and rate of the elevation line-of-sight. This drive axle becomes the stable element and is coupled to the mirror axle, at a 2:1 ratio, by means of gears or metallic belts or bands. This is a double axle gimbal system. When subjected to a rotational disturbance such as boat or vehicle motion the inertias of the drive and mirror axles react with one-another to cause a displacement of the line-of-sight pointing vector. This disturbance is a dynamic coupling of inertias. It exists even in the absence of friction

  15. Periscope-camera system for visible and infrared imaging diagnostics on TFTR

    SciTech Connect

    Medley, S.S.; Dimock, D.L.; Hayes, S.; Long, D.; Lowrence, J.L.; Mastrocola, V.; Renda, G.; Ulrickson, M.; Young, K.M.

    1985-05-01

    An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect vacuum vessel internal structures in both visible and near-infrared wavelength regions. Three periscopes view through 20-cm-diameter fused-silica windows which are spaced around the torus midplane to provide a viewing coverage of approximately 75% of the vacuum vessel internal surface area. The periscopes have f/8 optics and motor-driven controls for focusing, magnification selection (5/sup 0/, 20/sup 0/, and 60/sup 0/ field of view), elevation and azimuth setting, mast rotation, filter selection, iris aperture, and viewing port selection. The four viewing ports on each periscope are equipped with multiple imaging devices which include: (1) an inspection eyepiece, (2) standard (RCA TC2900) and fast (RETICON) framing rate television cameras, (3) a PtSi CCD infrared imaging camera, (4) a 35 mm Nikon F3 still camera, or (5) a 16 mm Locam II movie camera with variable framing up to 500 fps. Operation of the periscope-camera system is controlled either locally or remotely through a computer-CAMAC interface. A description of the equipment and examples of its application are presented.

  16. Periscope for noninvasive two-photon imaging of murine retina in vivo

    PubMed Central

    Stremplewski, Patrycjusz; Komar, Katarzyna; Palczewski, Krzysztof; Wojtkowski, Maciej; Palczewska, Grazyna

    2015-01-01

    Two-photon microscopy allows visualization of subcellular structures in the living animal retina. In previously reported experiments it was necessary to apply a contact lens to each subject. Extending this technology to larger animals would require fitting a custom contact lens to each animal and cumbersome placement of the living animal head on microscope stage. Here we demonstrate a new device, periscope, for coupling light energy into mouse eye and capturing emitted fluorescence. Using this periscope we obtained images of the RPE and their subcellular organelles, retinosomes, with larger field of view than previously reported. This periscope provides an interface with a commercial microscope, does not require contact lens and its design could be modified to image retina in larger animals. PMID:26417507

  17. Polarization property analysis of a periscopic scanner with three-dimensional polarization ray-tracing calculus.

    PubMed

    Yang, Yufei; Yan, Changxiang

    2016-02-20

    The polarization properties of a two-axis periscopic optical scanner constituted by a pair of rotating planar mirrors have been studied by using the three-dimensional polarization ray-tracing matrix method. The separate and cumulative matrices that define the transformation of the polarization state are obtained and expressed in terms of the rotation angles of two mirrors. The variations of diattenuation and retardance are investigated and graphically shown as functions of the rotation angles. On this basis, a further investigation about the cumulative polarization aberrations of three different metal-coated periscopic scanners is accomplished. Finally, the output polarization states of the three metal-coated scanners are calculated with the input beam of the arbitrary polarization states, and the results show that aluminum film is more appropriate than gold film or silver film for the polarization-maintaining periscopic scanner.

  18. Polarization property analysis of a periscopic scanner with three-dimensional polarization ray-tracing calculus.

    PubMed

    Yang, Yufei; Yan, Changxiang

    2016-02-20

    The polarization properties of a two-axis periscopic optical scanner constituted by a pair of rotating planar mirrors have been studied by using the three-dimensional polarization ray-tracing matrix method. The separate and cumulative matrices that define the transformation of the polarization state are obtained and expressed in terms of the rotation angles of two mirrors. The variations of diattenuation and retardance are investigated and graphically shown as functions of the rotation angles. On this basis, a further investigation about the cumulative polarization aberrations of three different metal-coated periscopic scanners is accomplished. Finally, the output polarization states of the three metal-coated scanners are calculated with the input beam of the arbitrary polarization states, and the results show that aluminum film is more appropriate than gold film or silver film for the polarization-maintaining periscopic scanner. PMID:26906587

  19. Elusive Reaction Intermediates in Solution Explored by ESI-MS: Reverse Periscope for Mechanistic Investigations.

    PubMed

    Iacobucci, Claudio; Reale, Samantha; De Angelis, Francesco

    2016-02-24

    Just as periscopes allow a submarine to visually search for objects above the surface of the sea, in a reversed periscope fashion electrospray mass spectrometry (ESI-MS) can analyze the compounds at the gas phase/liquid phase interface for chemical entities which may exist in solution. The challenge is the identification and structural characterization of key elusive reaction intermediates in chemical transformations, intermediates which are able to explain how chemical processes occur. This Minireview summarizes recent selected publications on the use of ESI-MS techniques for studying solution intermediates of homogeneous chemical reactions. PMID:26799781

  20. Chimney and periscope technique for emergent treatment of spontaneous aortic rupture.

    PubMed

    Trellopoulos, George; Georgakarakos, Efstratios; Pelekas, Dimitrios; Papachristodoulou, Athanasia; Argyriou, Christos; Georgiadis, George S

    2014-07-01

    Aortic rupture comprises a potentially fatal condition necessitating emergent treatment. Endovascular sealing of the rupture site is often combined with the use of chimney- and periscope stent placement to preserve perfusion of aortic branches. We present a case of successful endovascular management of contained aortic rupture in a 78-year-old patient. The left brachial access facilitated stenting of the celiac and superior mesenteric arteries, whereas the left femoral route served stenting of the renal artery. One-month follow-up confirmed complete sealing, stent patency, and absence of endograft migration. The combined periscope and chimney technique is feasible and effective in the emergency setting. PMID:24517987

  1. Elusive Reaction Intermediates in Solution Explored by ESI-MS: Reverse Periscope for Mechanistic Investigations.

    PubMed

    Iacobucci, Claudio; Reale, Samantha; De Angelis, Francesco

    2016-02-24

    Just as periscopes allow a submarine to visually search for objects above the surface of the sea, in a reversed periscope fashion electrospray mass spectrometry (ESI-MS) can analyze the compounds at the gas phase/liquid phase interface for chemical entities which may exist in solution. The challenge is the identification and structural characterization of key elusive reaction intermediates in chemical transformations, intermediates which are able to explain how chemical processes occur. This Minireview summarizes recent selected publications on the use of ESI-MS techniques for studying solution intermediates of homogeneous chemical reactions.

  2. Periscope: quantitative prediction of soluble protein expression in the periplasm of Escherichia coli.

    PubMed

    Chang, Catherine Ching Han; Li, Chen; Webb, Geoffrey I; Tey, BengTi; Song, Jiangning; Ramanan, Ramakrishnan Nagasundara

    2016-01-01

    Periplasmic expression of soluble proteins in Escherichia coli not only offers a much-simplified downstream purification process, but also enhances the probability of obtaining correctly folded and biologically active proteins. Different combinations of signal peptides and target proteins lead to different soluble protein expression levels, ranging from negligible to several grams per litre. Accurate algorithms for rational selection of promising candidates can serve as a powerful tool to complement with current trial-and-error approaches. Accordingly, proteomics studies can be conducted with greater efficiency and cost-effectiveness. Here, we developed a predictor with a two-stage architecture, to predict the real-valued expression level of target protein in the periplasm. The output of the first-stage support vector machine (SVM) classifier determines which second-stage support vector regression (SVR) classifier to be used. When tested on an independent test dataset, the predictor achieved an overall prediction accuracy of 78% and a Pearson's correlation coefficient (PCC) of 0.77. We further illustrate the relative importance of various features with respect to different models. The results indicate that the occurrence of dipeptide glutamine and aspartic acid is the most important feature for the classification model. Finally, we provide access to the implemented predictor through the Periscope webserver, freely accessible at http://lightning.med.monash.edu/periscope/. PMID:26931649

  3. Periscope: quantitative prediction of soluble protein expression in the periplasm of Escherichia coli

    PubMed Central

    Chang, Catherine Ching Han; Li, Chen; Webb, Geoffrey I.; Tey, BengTi; Song, Jiangning; Ramanan, Ramakrishnan Nagasundara

    2016-01-01

    Periplasmic expression of soluble proteins in Escherichia coli not only offers a much-simplified downstream purification process, but also enhances the probability of obtaining correctly folded and biologically active proteins. Different combinations of signal peptides and target proteins lead to different soluble protein expression levels, ranging from negligible to several grams per litre. Accurate algorithms for rational selection of promising candidates can serve as a powerful tool to complement with current trial-and-error approaches. Accordingly, proteomics studies can be conducted with greater efficiency and cost-effectiveness. Here, we developed a predictor with a two-stage architecture, to predict the real-valued expression level of target protein in the periplasm. The output of the first-stage support vector machine (SVM) classifier determines which second-stage support vector regression (SVR) classifier to be used. When tested on an independent test dataset, the predictor achieved an overall prediction accuracy of 78% and a Pearson’s correlation coefficient (PCC) of 0.77. We further illustrate the relative importance of various features with respect to different models. The results indicate that the occurrence of dipeptide glutamine and aspartic acid is the most important feature for the classification model. Finally, we provide access to the implemented predictor through the Periscope webserver, freely accessible at http://lightning.med.monash.edu/periscope/. PMID:26931649

  4. Up Periscope! Designing a New Perceptual Metric for Imaging System Performance

    NASA Technical Reports Server (NTRS)

    Watson, Andrew B.

    2016-01-01

    Modern electronic imaging systems include optics, sensors, sampling, noise, processing, compression, transmission and display elements, and are viewed by the human eye. Many of these elements cannot be assessed by traditional imaging system metrics such as the MTF. More complex metrics such as NVTherm do address these elements, but do so largely through parametric adjustment of an MTF-like metric. The parameters are adjusted through subjective testing of human observers identifying specific targets in a set of standard images. We have designed a new metric that is based on a model of human visual pattern classification. In contrast to previous metrics, ours simulates the human observer identifying the standard targets. One application of this metric is to quantify performance of modern electronic periscope systems on submarines.

  5. CHICAGO, PERISCOPE and PROactive: CV risk modification in diabetes with pioglitazone.

    PubMed

    Betteridge, D John

    2009-12-01

    Recent trials of intensive glycaemic control in patients with type 2 diabetes and its impact on cardiovascular disease have led to confusion and speculation amongst physicians. The Action to Control Cardiovascular Risk in Diabetes Study was terminated early because of a significant excess all-cause mortality in the intensively-treated group. Furthermore the ADVANCE and VADT trials did not demonstrate cardiovascular benefit with more intensive glycaemic control. Against this background, it is pertinent to re-visit and critically appraise the results of the PROactive study which examined the effects of the thiazolidinedione, pioglitazone, on cardiovascular end-points in a large, randomized, placebo-controlled clinical trial in type 2 diabetic patients with symptomatic disease. PROactive has been rightly criticized in the choice of its composite primary end-point which included a physician-driven as opposed to a disease-driven outcome, namely peripheral vascular re-vascularization. This was primarily responsible for the primary composite end-point not being achieved; whereas there was a significant beneficial impact on the major secondary end-point of death, non-fatal myocardial infarction and stroke. The results of PROactive have been supported by two subsequent studies examining the impact of pioglitazone on important surrogates of atherosclerosis, namely carotid intima/medial thickness (IMT) and coronary atheroma volume as delineated with intravascular ultrasound. The CHICAGO study demonstrated that IMT in type 2 diabetic patients treated with pioglitazone did not progress whereas those treated with glimepiride showed progression. In PERISCOPE atheroma volume progressed with glimepiride but did not with pioglitazone. This is exciting data pointing to the cardiovascular benefits of pioglitazone. In PROactive, CHICAGO and PERISCOPE there was a sustained effect of pioglitazone on glycaemic control and, in addition, beneficial effects in reducing triglycerides and

  6. Forensic reporting of a case of sexual abuse broadcast on periscope.

    PubMed

    Nasıroğlu, Serhat; Çimen, İrem Damla

    2016-01-01

    Children who are investigated or prosecuted for an action that is considered a crime by the law, or children who were placed in security facilities due to his/her actions are defined as "children forced into crime". The period between ages 12-18 years is adolescence, during which crime rates are relatively high. The incidence of sexual behavior of adolescents on social media, which may be considered a crime, has increased in recent years due to technological improvements and increase in the use of social media. Also, the crime rates involving adolescents have increased due to environmental influences, familial factors, and mental disorders. Mental disorders such as conduct disorder, attention deficit hyperactivity disorder, and mood disorders have been found to be associated with sexual abuse in young persons in previous literature. In this study, we present the case of a boy who sexually abused his younger brother at the age of 14 years 2 months and broadcast this abuse on "Periscope". In this case study, we aimed to discuss the relationships between sexual abuse, social media, and psychiatric disorders. PMID:27578979

  7. Modeling and analysis of a high-performance midwave infrared panoramic periscope

    NASA Astrophysics Data System (ADS)

    Nichols, Jonathan M.; Waterman, James R.; Menon, Raghu; Devitt, John

    2010-11-01

    A high-resolution midwave infrared panoramic periscope sensor system has been developed. The sensor includes an f/2.5 catadioptric optical system that provides a field of view with 360-deg horizontal azimuth and -10- to +30-deg elevation without requiring moving components (e.g., rotating mirrors). The focal plane is a 2048×2048, 15-μm-pitch InSb detector operating at 80 K. An onboard thermoelectric reference source allows for real-time nonuniformity correction using the two-point correction method. The entire system (detector-Dewar assembly, cooler, electronics, and optics) is packaged to fit in an 8-in.-high, 6.5-in.-diameter volume. This work describes both the system optics and the electronics and presents sample imagery. We model both the sensor's radiometric performance, quantified by the noise-equivalent temperature difference, and its resolution performance. Model predictions are then compared with estimates obtained from experimental data. The ability of the system to resolve targets as a function of imaged spatial frequency is also presented.

  8. Endovascular Treatment of a Symptomatic Thoracoabdominal Aortic Aneurysm by Chimney and Periscope Techniques for Total Visceral and Renal Artery Revascularization

    SciTech Connect

    Cariati, Maurizio; Mingazzini, Pietro; Dallatana, Raffaello; Rossi, Umberto G.; Settembrini, Alberto; Santuari, Davide

    2013-05-02

    Conventional endovascular therapy of thoracoabdominal aortic aneurysm with involving visceral and renal arteries is limited by the absence of a landing zone for the aortic endograft. Solutions have been proposed to overcome the problem of no landing zone; however, most of them are not feasible in urgent and high-risk patients. We describe a case that was successfully treated by total endovascular technique with a two-by-two chimney-and-periscope approach in a patient with acute symptomatic type IV thoracoabdominal aortic aneurysm with supra-anastomotic aneurysm formation involving the renal and visceral arteries and a pseduaneurismatic sac localized in the left ileopsoas muscle.

  9. Wiring a periscope--ocelli, retinula axons, visual neuropils and the ancestrality of sea spiders.

    PubMed

    Lehmann, Tobias; Hess, Martin; Melzer, Roland R

    2012-01-01

    The Pycnogonida or sea spiders are cryptic, eight-legged arthropods with four median ocelli in a 'periscope' or eye tubercle. In older attempts at reconstructing phylogeny they were Arthropoda incertae sedis, but recent molecular trees placed them as the sister group either to all other euchelicerates or even to all euarthropods. Thus, pycnogonids are among the oldest extant arthropods and hold a key position for the understanding of arthropod evolution. This has stimulated studies of new sets of characters conductive to cladistic analyses, e.g. of the chelifores and of the hox gene expression pattern. In contrast knowledge of the architecture of the visual system is cursory. A few studies have analysed the ocelli and the uncommon "pseudoinverted" retinula cells. Moreover, analyses of visual neuropils are still at the stage of Hanström's early comprehensive works. We have therefore used various techniques to analyse the visual fibre pathways and the structure of their interrelated neuropils in several species. We found that pycnogonid ocelli are innervated to first and second visual neuropils in close vicinity to an unpaired midline neuropil, i.e. possibly the arcuate body, in a way very similar to ancestral euarthropods like Euperipatoides rowelli (Onychophora) and Limulus polyphemus (Xiphosura). This supports the ancestrality of pycnogonids and sheds light on what eyes in the pycnogonid ground plan might have 'looked' like. Recently it was suggested that arthropod eyes originated from simple ocelli similar to larval eyes. Hence, pycnogonid eyes would be one of the early offshoots among the wealth of more sophisticated arthropod eyes. PMID:22279594

  10. Improved signal to noise ratio and sensitivity of an infrared imaging video bolometer on large helical device by using an infrared periscope

    SciTech Connect

    Pandya, Shwetang N. Sano, Ryuichi; Peterson, Byron J.; Mukai, Kiyofumi; Enokuchi, Akito; Takeyama, Norihide

    2014-07-15

    An Infrared imaging Video Bolometer (IRVB) diagnostic is currently being used in the Large Helical Device (LHD) for studying the localization of radiation structures near the magnetic island and helical divertor X-points during plasma detachment and for 3D tomography. This research demands high signal to noise ratio (SNR) and sensitivity to improve the temporal resolution for studying the evolution of radiation structures during plasma detachment and a wide IRVB field of view (FoV) for tomography. Introduction of an infrared periscope allows achievement of a higher SNR and higher sensitivity, which in turn, permits a twofold improvement in the temporal resolution of the diagnostic. Higher SNR along with wide FoV is achieved simultaneously by reducing the separation of the IRVB detector (metal foil) from the bolometer's aperture and the LHD plasma. Altering the distances to meet the aforesaid requirements results in an increased separation between the foil and the IR camera. This leads to a degradation of the diagnostic performance in terms of its sensitivity by 1.5-fold. Using an infrared periscope to image the IRVB foil results in a 7.5-fold increase in the number of IR camera pixels imaging the foil. This improves the IRVB sensitivity which depends on the square root of the number of IR camera pixels being averaged per bolometer channel. Despite the slower f-number (f/# = 1.35) and reduced transmission (τ{sub 0} = 89%, due to an increased number of lens elements) for the periscope, the diagnostic with an infrared periscope operational on LHD has improved in terms of sensitivity and SNR by a factor of 1.4 and 4.5, respectively, as compared to the original diagnostic without a periscope (i.e., IRVB foil being directly imaged by the IR camera through conventional optics). The bolometer's field of view has also increased by two times. The paper discusses these improvements in apt details.

  11. Periscope: Views of the Individualized Education Program.

    ERIC Educational Resources Information Center

    Weiner, Bluma B., Ed.

    The collection of 41 papers from a conference on individualized education programs (IEPs) for handicapped students addresses four main topics (sample titles and authors in parentheses): communication and group process ("Establishing and Maintaining the IEP Team" by W. Morgan and N. Bray; "Child and Parent Involvement in Educational Planning" by M.…

  12. Forensic reporting of a case of sexual abuse broadcast on periscope

    PubMed Central

    Nasıroğlu, Serhat; Çimen, İrem Damla

    2016-01-01

    Children who are investigated or prosecuted for an action that is considered a crime by the law, or children who were placed in security facilities due to his/her actions are defined as “children forced into crime”. The period between ages 12–18 years is adolescence, during which crime rates are relatively high. The incidence of sexual behavior of adolescents on social media, which may be considered a crime, has increased in recent years due to technological improvements and increase in the use of social media. Also, the crime rates involving adolescents have increased due to environmental influences, familial factors, and mental disorders. Mental disorders such as conduct disorder, attention deficit hyperactivity disorder, and mood disorders have been found to be associated with sexual abuse in young persons in previous literature. In this study, we present the case of a boy who sexually abused his younger brother at the age of 14 years 2 months and broadcast this abuse on “Periscope”. In this case study, we aimed to discuss the relationships between sexual abuse, social media, and psychiatric disorders. PMID:27578979

  13. Endovascular Repair of Acute Symptomatic Pararenal Aortic Aneurysm With Three Chimney and One Periscope Graft for Complete Visceral Artery Revascularization

    SciTech Connect

    Brechtel, Klaus Ketelsen, Dominik; Endisch, Andrea; Heller, Stephan; Heuschmid, Martin; Stock, Ulrich A.; Kalender, Guenay

    2012-04-15

    PurposeTo describe a modified endovascular technique for complete revascularization of visceral and renal arteries in symptomatic pararenal aortic aneurysm (PRAA).TechniqueArterial access was surgically established in both common femoral arteries (CFAs) and the left subclavian artery (LSA). Revascularization of the left renal artery, the celiac trunk, and the superior mesenteric artery was performed through one single sheath via the LSA. Suitable covered stents were put in the aortic branches but not deployed. The right renal artery was accessed over the left CFA. Due to the longitudinal extension of the presented aneurysm two stent-grafts were introduced via the right CFA. After deploying the aortic stent-grafts, all covered stents in the side branches were deployed consecutively with a minimum overlap of 5 mm over the cranial and caudal stent-graft edges. Simultaneous ballooning was performed to fully expand all stent-grafts and warranty patency. Conclusion: This is the first report in the literature of chimney grafting in PRAA for complete revascularization of visceral and renal branches by using more than two covered stents introduced from one side through one single sheath. However this technique is modified, it should be used only in bailout situations when branched stent-grafts are not available and/or surgery is not suitable.

  14. 33. HISTORIC VIEW OF WERNHER VON BRAUN LOOKS THROUGH THE ...

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

    33. HISTORIC VIEW OF WERNHER VON BRAUN LOOKS THROUGH THE PERISCOPE FROM THE CONTROL ROOM AT TEST STAND NO. 1, PEENEMUENDE. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  15. VIEW LOOKING NORTHEAST AT EARTH MOUND. NOTE THE RECTANGULAR OPENINGS ...

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

    VIEW LOOKING NORTHEAST AT EARTH MOUND. NOTE THE RECTANGULAR OPENINGS USED FOR OBSERVATION EQUIPMENT AND PERISCOPE TOPS. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  16. Upgrade of the Edge Charge Exchange Diagnostic on Alcator C-Mod

    NASA Astrophysics Data System (ADS)

    McDermott, Rachael; Lipschultz, Bruce; Marr, Kenneth

    2006-10-01

    The current edge Charge Exchange Spectroscopy system is being upgraded to include both a beam viewing and a background viewing toroidal periscope. The beam viewing periscope will be focused on the center of the DNB and will cover a 4cm radial region at the edge of the plasma starting a few centimeters in from and extending up to 1centimeter outside of the last closed flux surface. The background periscope will view the same radial region but will be displaced toroidally by 36 degrees. Each periscope has 20 chordal views with a radial resolution of 2.5-3mm. The presence of a background periscope obviates the need for a chopped DNB by providing time synchronized background B^+4 spectral data that can be subtracted directly from the active beam-derived B^+4 line-shapes. This system has been designed to work in conjunction with the current poloidal Charge Exchange periscope which has 25 fibers focused in the same region with equivalent radial resolution. The new toroidal system will enable concurrent measurements of the poloidal and toroidal velocity as well as the temperature and density of the B^+5 ions in the edge pedestal region; a measurement that currently does not exist on C-Mod. This information will then be used to calculate radial electric field profiles and study edge physics phenomena.

  17. Experimental evaluation of achromatic phase shifters for mid-infrared starlight suppression.

    PubMed

    Gappinger, Robert O; Diaz, Rosemary T; Ksendzov, Alexander; Lawson, Peter R; Lay, Oliver P; Liewer, Kurt M; Loya, Frank M; Martin, Stefan R; Serabyn, Eugene; Wallace, James K

    2009-02-10

    Phase shifters are a key component of nulling interferometry, one of the potential routes to enabling the measurement of faint exoplanet spectra. Here, three different achromatic phase shifters are evaluated experimentally in the mid-infrared, where such nulling interferometers may someday operate. The methods evaluated include the use of dispersive glasses, a through-focus field inversion, and field reversals on reflection from antisymmetric flat-mirror periscopes. All three approaches yielded deep, broadband, mid-infrared nulls, but the deepest broadband nulls were obtained with the periscope architecture. In the periscope system, average null depths of 4x10(-5) were obtained with a 25% bandwidth, and 2x10(-5) with a 20% bandwidth, at a central wavelength of 9.5 mum. The best short term nulls at 20% bandwidth were approximately 9x10(-6), in line with error budget predictions and the limits of the current generation of hardware. PMID:19209197

  18. IET. Construction view of control building (TAN620). Camera facing east, ...

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

    IET. Construction view of control building (TAN-620). Camera facing east, towards west wall of control building. Structure at left shows progress forming the personnel tunnel that will connect control building to coupling station. Note two round openings for periscopes near ladder at right. Date: August 20, 1954. INEEL negative no. 11709 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  19. 25. VIEW OF ATLAS CONTROL CONSOLE NEAR NORTHEAST CORNER OF ...

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

    25. VIEW OF ATLAS CONTROL CONSOLE NEAR NORTHEAST CORNER OF SLC-3W CONTROL ROOM. CONSOLE INCLUDES TELEVISION CONTROL, FACILITIES, AND VEHICLE (MISSILE) POWER PANELS. FROM LEFT TO RIGHT IN BACKGROUND: MILITARY-TIME CLOCK, BASE OF BUNKER PERISCOPE, AND STAIRS TO ESCAPE TUNNEL. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  20. IET control building (TAN620). control room. facing north. control consoles ...

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

    IET control building (TAN-620). control room. facing north. control consoles have been removed. Openings in floor were communication and control conduits. Periscope controls at center left (see also HAER No. ID-33-E-20). INEEL negative no. HD-21-3-1 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  1. DETAIL VIEW OF THE WEST INTERIOR WALL OF THE EXTREME ...

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

    DETAIL VIEW OF THE WEST INTERIOR WALL OF THE EXTREME NORTH (CONTROL) TANK. NOTE THE TWO PERISCOPES IN THE UPPER PART OF THE PHOTOGRAPH. ALSO NOTE THE CONTROL PANEL IN THE MIDDLE OF THE PHOTO, THIS WAS USED TO CONTROL THE REMOTE 'FIRE-EX' WATER NOZZLES. - Marshall Space Flight Center, Redstone Rocket (Missile) Test Stand, Dodd Road, Huntsville, Madison County, AL

  2. 1990 waste tank inspection program

    SciTech Connect

    McNatt, F.G.

    1990-12-31

    Aqueous radioactive wastes from Savannah River Site separations processes are contained in large underground carbon steel tanks. Tank conditions are evaluated by inspection using periscopes, still photography, and video systems for visual imagery. Inspections made in 1990 are the subject of this report.

  3. 1990 waste tank inspection program

    SciTech Connect

    McNatt, F.G.

    1990-01-01

    Aqueous radioactive wastes from Savannah River Site separations processes are contained in large underground carbon steel tanks. Tank conditions are evaluated by inspection using periscopes, still photography, and video systems for visual imagery. Inspections made in 1990 are the subject of this report.

  4. Innovative optronics for the new PUMA tank

    NASA Astrophysics Data System (ADS)

    Fritze, J.; Münzberg, M.; Schlemmer, H.

    2010-04-01

    The new PUMA tank is equipped with a fully stabilized 360° periscope. The thermal imager in the periscope is identical to the imager in the gunner sight. All optronic images of the cameras can be fed on every electronic display within the tank. The thermal imagers operate with a long wave 384x288 MCT starring focal plane array. The high quantum efficiency of MCT provides low NETD values at short integration times. The thermal imager has an image resolution of 768x576 pixels by means of a micro scanner. The MCT detector operates at high temperatures above 75K with high stability in noise and correctibility and offers high reliability (MTTF) values for the complete camera in a very compact design. The paper discusses the principle and functionality of the optronic combination of direct view optical channel, thermal imager and visible camera and discusses in detail the performances of the subcomponents with respect to demands for new tank applications.

  5. Establishment Of System Design Requirements Of The DIVAD Visual Fire Control Optics

    NASA Astrophysics Data System (ADS)

    Felts, Loren D.

    1982-05-01

    The develoment of the specified optical system parameters is followed from initial constraints, recuirements, and scenarios. The process includes consulting with the optical designers, to keep the design practical and performing analyses, to define the system configuration, such as amortioning apertures and spectral bands. The fire control system consists, of two sighting systems, a search sensor called the Squad Leader's, Periscope and a tracking system with integral laser rangefinder called. the. Gunner's Sight. Both systems are stabilized and have a night vision capability.

  6. IET. Coupling station (TAN620), plans and sections. Concrete shielding walls ...

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

    IET. Coupling station (TAN-620), plans and sections. Concrete shielding walls and boron surface treatment. Elevation shows two floor levels, position of periscopes, and stairways. Ralph M. Parsons 902-4-ANP-602-A 325. Date: February 1954. Approved by INEEL Classification Office for public release. INEEL index code no. 035-0620-00-693-106910 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  7. Considerations for patients undergoing endovascular abdominal aortic aneurysm repair.

    PubMed

    Ullery, Brant W; Lee, Jason T

    2014-09-01

    Endovascular aneurysm repair has taken over open surgery as the primary strategy for treatment of patients with abdominal and thoracic aneurysms. The minimally invasive nature of these techniques requires alterations in preoperative workup, intraoperative management, and familiarity with unique complications that can occur. Familiarity from the anesthetic standpoint of endovascular techniques, including treatment of patients with fenestrated, chimney, snorkel, and periscope grafts, is necessary for the contemporary cardiac anesthesiologist.

  8. IET. Movable test cell building (TAN624). Plans, sections, and elevations ...

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

    IET. Movable test cell building (TAN-624). Plans, sections, and elevations show trapezoidal shape of front/rear elevations, vertical sliding door panels, wheels, periscope and camera locations, fixed concrete wall, and relationship to coupling station (TAN-620) and rail track. Ralph M. Parson 902-4-ANP-624-A 329. Date: February 1954. Approved by INEEL Classification Office for public release. INEEL Index code no. 035-0624-00-693-106911 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  9. C-III flow measurements with a coherence imaging spectrometer

    SciTech Connect

    Weber, T. R.; Allen, S. L.; Howard, J.

    2012-10-15

    This work describes a coherence imaging spectrometer capable of making spatially resolved CIII flow measurements in the DIII-D lower divertor. The spectrometer exploits a periscope view of the plasma to produce line-of-sight averaged velocity measurements of CIII. From these chord averaged flow measurements, a 2D poloidal cross section of the CIII flow is tomographically reconstructed. Details of the diagnostic setup, acquired data, and data analysis will be presented, along with prospects for future applications.

  10. Streambank plants vital to water quality

    SciTech Connect

    Sherman, H.

    1989-08-01

    Studies of plants suitable for stabilizing streambanks are described. Sediments caused by soil erosion in Northern California's mountain meadows clog drinking water reservoirs, reduce fish populations, and block hydroelectric dams. Studies of the effect of seasonal climate change on root growth, photosynthesis, and water use of willows and grasses using a below-ground periscope and portable photosynthesis are described. In addition, studies to evaluate the seasonal effect of livestock grazing are in progress.

  11. A model for the submarine depthkeeping team

    NASA Technical Reports Server (NTRS)

    Ware, J. R.; Best, J. F.; Bozzi, P. J.; Kleinman, D. W.

    1981-01-01

    The most difficult task the depthkeeping team must face occurs during periscope-depth operations during which they may be required to maintain a submarine several hundred feet long within a foot of ordered depth and within one-half degree of ordered pitch. The difficulty is compounded by the facts that wave generated forces are extremely high, depth and pitch signals are very noisy and submarine speed is such that overall dynamics are slow. A mathematical simulation of the depthkeeping team based on the optimal control models is described. A solution of the optimal team control problem with an output control restriction (limited display to each controller) is presented.

  12. Improved spatial calibration for the CXRS system on EAST

    NASA Astrophysics Data System (ADS)

    Yin, X. H.; Li, Y. Y.; Fu, J.; Jiang, D.; Feng, S. Y.; Gu, Y. Q.; Cheng, Y.; Lyu, B.; Shi, Y. J.; Ye, M. Y.; Wan, B. N.

    2016-11-01

    A Charge eXchange Recombination Spectroscopy (CXRS) diagnostic system has been developed to measure profiles of ion temperature and rotation since 2014 on EAST. Several techniques have been developed to improve the spatial calibration of the CXRS diagnostic. The sightline location was obtained by measuring the coordinates of three points on each sightline using an articulated flexible coordinate measuring arm when the vessel was accessible. After vacuum pumping, the effect of pressure change in the vacuum vessel was evaluated by observing the movement of the light spot from back-illuminated sightlines on the first wall using the newly developed articulated inspection arm. In addition, the rotation of the periscope after vacuum pumping was derived by using the Doppler shift of neutral beam emission spectra without magnetic field. Combining these techniques, improved spatial calibration was implemented to provide a complete and accurate description of the EAST CXRS system. Due to the effects of the change of air pressure, a ˜0.4° periscope rotation, yielding a ˜20 mm movement of the major radius of observation positions to the lower field side, was derived. Results of Zeeman splitting of neutral beam emission spectra with magnetic field also showed good agreement with the calibration results.

  13. Transverse Pupil Shifts for Adaptive Optics Non-Common Path Calibration

    NASA Technical Reports Server (NTRS)

    Bloemhof, Eric E.

    2011-01-01

    A simple new way of obtaining absolute wavefront measurements with a laboratory Fizeau interferometer was recently devised. In that case, the observed wavefront map is the difference of two cavity surfaces, those of the mirror under test and of an unknown reference surface on the Fizeau s transmission flat. The absolute surface of each can be determined by applying standard wavefront reconstruction techniques to two grids of absolute surface height differences of the mirror under test, obtained from pairs of measurements made with slight transverse shifts in X and Y. Adaptive optics systems typically provide an actuated periscope between wavefront sensor (WFS) and commonmode optics, used for lateral registration of deformable mirror (DM) to WFS. This periscope permits independent adjustment of either pupil or focal spot incident on the WFS. It would be used to give the required lateral pupil motion between common and non-common segments, analogous to the lateral shifts of the two phase contributions in the lab Fizeau. The technique is based on a completely new approach to calibration of phase. It offers unusual flexibility with regard to the transverse spatial frequency scales probed, and will give results quite quickly, making use of no auxiliary equipment other than that built into the adaptive optics system. The new technique may be applied to provide novel calibration information about other optical systems in which the beam may be shifted transversely in a controlled way.

  14. Metrology system for inter-alignment of lasers, telescopes, and mechanical datum

    NASA Astrophysics Data System (ADS)

    Aharon, Oren; Vishnia, Itai

    2015-10-01

    In modern scientific and industrial laser applications, inter-alignment of multiple optical devices is frequently a basic requirement to meet a certain specification and performance. However, the designed optical system combining mechanical elements, lasers and optical sights in various wavelengths frequently deviates from specified goals due to real life imperfections and effects. These may include mechanical tolerances, optical distortion, heating, laser cavity misalignment, overall instabilities, and non-linear effects. In order to deliver accurately and produce intricate optical systems, a carefully designed method for inter-alignment is required completing and updating the already existing methods. Thus, we designed and upgraded the performance of electronic autocollimator and combined it with innovative mechanical manipulation of optical invariants such as a Lateral Transfer Hollow Periscope to greatly improve and expand inter-alignment procedures. Depending on the combination of optical sights, laser types, and mechanical requirements, an appropriate method will be analyzed. For example, several layouts will be analyzed such as high power CO2 laser cavity alignment and laser delivery system mechanical rollers alignment. By completing the presented gear in this article other instruments such as Align Meter, Lateral Hollow Periscope (LTHPTM), Lateral Hollow Retroreflector ( LTHRTM) are available for applications such as alignment of articulated beam delivery systems.

  15. Progress Report on the Student Astronomy Lab telescope at the University of Denver

    NASA Astrophysics Data System (ADS)

    Mellon, R. R.; Scheld, D. L.; Stencel, R. E.

    2004-05-01

    Integration and test activities associated with a new telescope for the Student Astronomy Laboratory (SAL) at the University of Denver are currently nearing completion on the main Denver campus. The 76.2-cm aperture SAL telescope incorporates novel design features, enabling it to operate as the first professional astronomical teaching and research telescope expressly designed to include use by wheelchair accommodated observers. The telescope is located 23-m above ground level on the fifth floor roof of the Space Sciences Laboratory building and is supported by a steel tower structure from the fourth floor support beams in the NW corner of the building. An afocal Mersenne optical configuration is used to send a collimated beam through the RA and DEC axes of the mounting, through a figure-4 mirror set, and thence vertically downward into a periscope, where condensing optics form an image plane accessible to visible band and IR detectors. A technical description of the telescope installation is provided, along with photographs illustrating key design features. Wheelchair-bound observers can enter the fourth floor lab and make use of an eye-level eyepiece when suitable periscope optics are installed. The SAL installation will be accessible to visitors by pre-arrangement with DU Observatories during the Denver AAS meeting [#204]. We are grateful to Glenn Montgpomery, Sarah Nelson and the estate of William Herschel Womble for their support of this University of Denver astronomy project.

  16. Live capture of megafauna from 2300 m depth, using a newly designed Pressurized Recovery Device

    NASA Astrophysics Data System (ADS)

    Shillito, B.; Hamel, G.; Duchi, C.; Cottin, D.; Sarrazin, J.; Sarradin, P.-M.; Ravaux, J.; Gaill, F.

    2008-07-01

    The deep sea is an extremely diverse habitat, which is now threatened by human activity. Means for evaluating the response of deep-sea creatures to environmental perturbation are limited because of lethal decompression effects during sampling. The addressing of this issue requires that target species be (i) captured at depth, (ii) recovered at natural pressure, (iii) submitted to in vivo investigations. Although a single container may meet these requirements, we believe that using several dedicated cells greatly expands experimental possibilities. Accordingly, we have designed a new sampling system which has been named PERISCOP and which has accounted for the selective capture and recovery of live animals from depths exceeding 2000 m. Three hydrothermal vent shrimp species were sampled on the Mid-Atlantic Ridge, from depths of 1700 and 2300 m. In addition, a fish caught at 2300 m depth reached the surface in very good condition. This is by far the deepest record for the pressurized recovery of a live deep-sea fish. Our prototype aims at making pressurized recovery a more efficient and practical process. Finally, future evolutions of sampling methods are discussed based on the present design of the PERISCOP.

  17. Opto-mechanical designs for two special-purpose objective lens assemblies

    NASA Astrophysics Data System (ADS)

    Yoder, Paul R., Jr.

    1986-01-01

    Key features of the optomechanical designs for two high-performance objective-lens assemblies of similar focal lengths and relative apertures, but significantly different configurations and applications are discussed. The first lens is a 25.4-cm EFL, f/1.5 catadioptric lens designed for a + or - 2.8-degree field and intended for use with a detector array in a spaceborne star mapper. The second example is a 22.8-cm EFL, f/1.5 refractor covering a + or - 10-degree field, intended for distant target observation in an airborne low-light-level visual periscope and featuring an integral laser channel for target designation and ranging. The logic behind critical materials choices and the techniques applied in mounting the optics in their mechanical surrounds are described.

  18. Electron beam irradiated silver nanowires for a highly transparent heater

    PubMed Central

    Hong, Chan-Hwa; Oh, Seung Kyu; Kim, Tae Kyoung; Cha, Yu-Jung; Kwak, Joon Seop; Shin, Jae-Heon; Ju, Byeong-Kwon; Cheong, Woo-Seok

    2015-01-01

    Transparent heaters have attracted increasing attention for their usefulness in vehicle windows, outdoor displays, and periscopes. We present high performance transparent heaters based on Ag nanowires with electron beam irradiation. We obtained an Ag-nanowire thin film with 48 ohm/sq of sheet resistance and 88.8% (substrate included) transmittance at 550 nm after electron beam irradiation for 120 sec. We demonstrate that the electron beam creates nano-soldering at the junctions of the Ag nanowires, which produces lower sheet resistance and improved adhesion of the Ag nanowires. We fabricated a transparent heater with Ag nanowires after electron beam irradiation, and obtained a temperature of 51 °C within 1 min at an applied voltage of 7 V. The presented technique will be useful in a wide range of applications for transparent heaters. PMID:26639760

  19. Electron beam irradiated silver nanowires for a highly transparent heater

    NASA Astrophysics Data System (ADS)

    Hong, Chan-Hwa; Oh, Seung Kyu; Kim, Tae Kyoung; Cha, Yu-Jung; Kwak, Joon Seop; Shin, Jae-Heon; Ju, Byeong-Kwon; Cheong, Woo-Seok

    2015-12-01

    Transparent heaters have attracted increasing attention for their usefulness in vehicle windows, outdoor displays, and periscopes. We present high performance transparent heaters based on Ag nanowires with electron beam irradiation. We obtained an Ag-nanowire thin film with 48 ohm/sq of sheet resistance and 88.8% (substrate included) transmittance at 550 nm after electron beam irradiation for 120 sec. We demonstrate that the electron beam creates nano-soldering at the junctions of the Ag nanowires, which produces lower sheet resistance and improved adhesion of the Ag nanowires. We fabricated a transparent heater with Ag nanowires after electron beam irradiation, and obtained a temperature of 51 °C within 1 min at an applied voltage of 7 V. The presented technique will be useful in a wide range of applications for transparent heaters.

  20. Optical tomographic scanning target-tracking system based on single pixel sensor

    NASA Astrophysics Data System (ADS)

    Li, Baosheng; Wang, Yicheng; Yang, Jiuchun

    2015-11-01

    Optical tomography imaging had the characteristics of high resolution. The rotating periscope system and modulating plate with 65 slits were designed. Filter back projection (FBP) algorithm was applied to the one-dimensional signals, which were obtained by multi-angle scanning in modulating plate, to reconstruct two-dimensional image. Single pixel photoelectric sensor has high frequency response and can acquire high speed real-time signal. This work had carried on the simulation and experiment about scanning system based on the analysis and determination about the modulating plate's parameters, and verify the feasibility of scanning system. In this paper, the method plays an important role in developing novel target tracking system and provides deep foundation for deeper experimental research.

  1. Renal interventions during endovascular aneurysm repair.

    PubMed

    Davies, Mark G

    2013-12-01

    Renal insufficiency is a risk factor for mortality and morbidity during endovascular aneurysm repair. Multiple changes in practice have occurred to mitigate renal injury and renal dysfunction. Transrenal fixation does carry an increased risk of a decline in renal function in the medium term. Renal stenting for athero-occlusive disease during endovascular aneurysm repair needs careful consideration, as indications have changed and there are unexpected consequences with early vessel occlusion. The growing number of renal interventions during complex endovascular aneurysm repair with the advent of chimney snorkel/periscope techniques and the introduction of fenestrated grafts has shown the resilience of the intervention with relatively low renal issues (approximately 10%), but has also illustrated the need for additional device development.

  2. Manastash Ridge Observatory Autoguider Upgrade

    NASA Astrophysics Data System (ADS)

    Lozo, Jason; Huehnerhoff, Joseph; Armstrong, John; Davila, Adrian; Johnson, Courtney; McMaster, Alex; Olinger, Kyle

    2016-06-01

    The Astronomy Undergraduate Engineering Group (AUEG) at the University of Washington has designed and manufactured a novel autoguider system for the 0.8-meter telescope at the Manastash Ridge Observatory in Ellensburg, Washington. The system uses a pickoff mirror placed in the unused optical path, directing the outer field to the guide camera via a system of axi-symmetrically rotating relay mirrors (periscope). This allows the guider to sample nearly 7 times the area that would be possible with the same fixed detector. This system adds closed loop optical feedback to the tracking capabilities of the telescope. When tuned the telescope will be capable of acheiving 0.5 arcsecond tracking or better. Dynamic focusing of the primary optical path will also be an included feature of this system. This unique guider will be a much needed upgrade to the telescope allowing for increased scientific capability.

  3. Status of the DNB based ITER CXRS and BES diagnostic

    NASA Astrophysics Data System (ADS)

    von Hellermann, M.; Jaspers, R.; Biel, W.; Litnovsky, A.; Neubauer, O.; Pap, M.; Hawkes, N. C.; Marren, C.; Walton, B.; Kaschuck, Y.; Serov, V.; Tugarinov, S.; Vliegenthart, W.; Moddemeijer, K.; Walker, C.; Ingesson, C.

    2006-10-01

    A status report is given on recent joint activities on the ITER CXRS and BES diagnostic package. Expected measurement performances are reviewed as well as comprehensive discussions are led on an integral approach to the implementation of Core and Edge CXRS observation periscopes. The "first mirror" location, its operational temperature, maintenance issues, and optimization of optical imaging are addressed. In parallel to more technical aspects, particular attention has also been given to the development of common evaluation and modeling tools. One part of this work is linked to the modeling of spectra for existing fusion devices and their CXRS diagnostics and extrapolation to the ITER environment. The purpose of this effort is to provide tools for the optimization of spectroscopic instrumentation, and moreover, the specifications of a suitable diagnostic beam.

  4. Spectrum slicer for snapshot spectral imaging

    NASA Astrophysics Data System (ADS)

    Tamamitsu, Miu; Kitagawa, Yutaro; Nakagawa, Keiichi; Horisaki, Ryoichi; Oishi, Yu; Morita, Shin-ya; Yamagata, Yutaka; Motohara, Kentaro; Goda, Keisuke

    2015-12-01

    We propose and demonstrate an optical component that overcomes critical limitations in our previously demonstrated high-speed multispectral videography-a method in which an array of periscopes placed in a prism-based spectral shaper is used to achieve snapshot multispectral imaging with the frame rate only limited by that of an image-recording sensor. The demonstrated optical component consists of a slicing mirror incorporated into a 4f-relaying lens system that we refer to as a spectrum slicer (SS). With its simple design, we can easily increase the number of spectral channels without adding fabrication complexity while preserving the capability of high-speed multispectral videography. We present a theoretical framework for the SS and its experimental utility to spectral imaging by showing real-time monitoring of a dynamic colorful event through five different visible windows.

  5. Investigation of light source and scattering medium related to vapor-screen flow visualization in a supersonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Snow, W. L.; Morris, O. A.

    1984-01-01

    Methods for increasing the radiant in light sheets used for vapor screen set-ups were investigated. Both high-pressure mercury arc lamps and lasers were considered. Pulsed operation of the air-cooled 1-kW lamps increased the light output but decreased reliability. An ellipsoidal mirror improved the output of the air-cooled lamps by concentrating the light but increased the complexity of the housing. Water-cooled-4-kW lamps coupled with high-aperture Fresnel lenses provided reasonable improvements over the air-cooled lamps. Fanned laser beams measurements of scattered light versus dew point made in conjunction with successful attempts to control the fluid injection. A number of smoke generators are described and test results comparing smoke and vapor screens are shown. Finally, one test included a periscope system to relay the image to a camera outside the flow.

  6. Thoracic endovascular aortic repair for blunt thoracic aortic injuries in complex aortic arch vessels anatomies.

    PubMed

    Piffaretti, Gabriele; Carrafiello, Gianpaolo; Ierardi, Anna Maria; Mariscalco, Giovanni; Macchi, Edoardo; Castelli, Patrizio; Tozzi, Matteo; Franchin, Marco

    2015-08-01

    The aim of this study is to report the use of thoracic endovascular aortic repair (TEVAR) in blunt thoracic aortic injuries (BTAIs) presenting with complex anatomies of the aortic arch vessels. Two patients were admitted to our hospital for the management of BTAI. Anomalies were as follow: aberrant right subclavian artery (n = 1) and right-sided aortic arch with 5 vessels anatomy variant (n = 1). TEVAR was accomplished using parallel graft with periscope configuration in the patient with the aberrant right subclavian artery. At 12-month follow-up, computed tomography angiographies confirmed the exclusion of the BTAI, the stability of the endograft, the resolution of the pseudoaneurysm, and the patency of the parallel endograft. Aortic arch vessels variants and anomalies are not rare, and should be recognized and studied precisely to plan the most appropriate operative treatment. TEVAR proved to be effective even in complex anatomies.

  7. High-resolution, continuous field-of-view (FOV), non-rotating imaging system

    NASA Technical Reports Server (NTRS)

    Huntsberger, Terrance L. (Inventor); Stirbl, Robert C. (Inventor); Aghazarian, Hrand (Inventor); Padgett, Curtis W. (Inventor)

    2010-01-01

    A high resolution CMOS imaging system especially suitable for use in a periscope head. The imaging system includes a sensor head for scene acquisition, and a control apparatus inclusive of distributed processors and software for device-control, data handling, and display. The sensor head encloses a combination of wide field-of-view CMOS imagers and narrow field-of-view CMOS imagers. Each bank of imagers is controlled by a dedicated processing module in order to handle information flow and image analysis of the outputs of the camera system. The imaging system also includes automated or manually controlled display system and software for providing an interactive graphical user interface (GUI) that displays a full 360-degree field of view and allows the user or automated ATR system to select regions for higher resolution inspection.

  8. Simulation of homology models for the extracellular domains (ECD) of ErbB3, ErbB4 and the ErbB2-ErbB3 complex in their active conformations.

    PubMed

    Franco-Gonzalez, Juan Felipe; Ramos, Javier; Cruz, Victor L; Martínez-Salazar, Javier

    2013-02-01

    Epidermal growth factor receptors (EGFR) are associated with a number of biological processes and are becoming increasingly recognized as important therapeutic targets against cancer. In this work, we provide models based on homology for the extracellular domains (ECD) of ErbB3 and ErbB4 in their active conformations, including a Heregulin ligand, followed by further refinement of the models by molecular dynamics simulations at atomistic scale. We compare the results with a model built for ErbB2 based on crystallographic information and analyze the common features observed among members of the family, namely, the periscope movement of the dimerization arm and the hinge displacement of domain IV. Finally, we refine a model for the interaction of the ECDs corresponding to a ErbB2-ErbB3 heterodimer, which is widely recognized to have a high impact in cancer development.

  9. Aspects of high-temperature pyrometry for measurements in ultrahigh vacuum

    SciTech Connect

    Neuhaus, P.; Egry, I.; Lohoefer, G. )

    1992-01-01

    Containerless materials processing of liquid metals with the use of electromagnetic levitation requires contactless temperature measurement by pyrometry. For high temperatures and under high-vacuum conditions, the vapor pressure of the levitated metal drop increases, leading to evaporation losses of the sample material. This flux condenses on the cold parts of the experimental apparatus including the window in front of the pyrometer. As a result, the intensity of radiation reaching the pyrometer decreases, which is erroneously interpreted as a decrease in temperature. Several methods to protect the pyrometer against contamination have been proposed. In this paper, the authors report experimental tests of the concepts of shielding windows and mirror optics placed into the optical path between the sample and the pyrometer. Temperature measurements with a periscopic mirror system are also presented. 11 refs., 7 figs., 2 tabs.

  10. Hemispherical Field-of-View Above-Water Surface Imager for Submarines

    NASA Technical Reports Server (NTRS)

    Hemmati, Hamid; Kovalik, Joseph M.; Farr, William H.; Dannecker, John D.

    2012-01-01

    A document discusses solutions to the problem of submarines having to rise above water to detect airplanes in the general vicinity. Two solutions are provided, in which a sensor is located just under the water surface, and at a few to tens of meter depth under the water surface. The first option is a Fish Eye Lens (FEL) digital-camera combination, situated just under the water surface that will have near-full- hemisphere (360 azimuth and 90 elevation) field of view for detecting objects on the water surface. This sensor can provide a three-dimensional picture of the airspace both in the marine and in the land environment. The FEL is coupled to a camera and can continuously look at the entire sky above it. The camera can have an Active Pixel Sensor (APS) focal plane array that allows logic circuitry to be built directly in the sensor. The logic circuitry allows data processing to occur on the sensor head without the need for any other external electronics. In the second option, a single-photon sensitive (photon counting) detector-array is used at depth, without the need for any optics in front of it, since at this location, optical signals are scattered and arrive at a wide (tens of degrees) range of angles. Beam scattering through clouds and seawater effectively negates optical imaging at depths below a few meters under cloudy or turbulent conditions. Under those conditions, maximum collection efficiency can be achieved by using a non-imaging photon-counting detector behind narrowband filters. In either case, signals from these sensors may be fused and correlated or decorrelated with other sensor data to get an accurate picture of the object(s) above the submarine. These devices can complement traditional submarine periscopes that have a limited field of view in the elevation direction. Also, these techniques circumvent the need for exposing the entire submarine or its periscopes to the outside environment.

  11. Final summary report for 1989 inservice inspection (ISI) of SRS (Savannah River Site) 100-P Reactor tank

    SciTech Connect

    Morrison, J.M.; Loibl, M.W.

    1989-12-15

    The integrity of the SRS reactor tanks is a key factor affecting their suitability for continued service since, unlike the external piping system and components, the tanks are virtually irreplaceable. Cracking in various areas of the process water piping systems has occurred beginning in 1960 as a result of several degradation mechanisms, chiefly intergranular stress corrosion cracking (IGSCC) and chloride-induced transgranular cracking. IGSCC, currently the primary degradation mechanism, also occurred in the knuckle'' region (tank wall-to-bottom tube sheet transition piece) unique to C Reactor and was eventually responsible for that reactor being deactivated in 1985. A program of visual examinations of the SRS reactor tanks was initiated in 1968, which used a specially designed immersible periscope. Under that program the condition of the accessible tank welds and associated heat affected zones (HAZ) was evaluated on a five-year frequency. Prior to 1986, the scope of these inspections comprised approximately 20 percent of the accessible weld area. In late 1986 and early 1987 the scope of the inspections was expanded and a 100 percent visual inspection of accessible welds was performed of the P-, L-, and K-Reactor tanks. Supplemental dye penetrant examinations were performed in L Reactor on selected areas which showed visual indications. No evidence of cracking was detected in any of these inspections of the P-, L-, and K-Reactor tanks. 17 refs., 7 figs.

  12. Near infrared spectroscopy of the divertor region in the Alcator C-Mod tokamak

    NASA Astrophysics Data System (ADS)

    Furno, I.; Wurden, G. A.

    2004-10-01

    A new system for near infrared spectroscopic measurements (1.2-2.6 μm) is designed for the Alcator C-Mod tokamak. These measurements will provide a new window into understanding the physics of detached and/or high radiating plasmas. The system, located on top of the Alcator C-Mod concrete igloo, will view a 30×30 cm2 region of the lower divertor by means of a re-entrant 5 m long ZnSe based periscope. A McPherson 218 spectrometer will disperse the light that will then be detected by a thermoelectrically cooled InGaAs, 256-element linear image sensor. The signals from each pixel will be digitized by a 16-bit, 333 kHz analog/digital board and then transmitted over optical link to a personal computer (PC) located in Alcator C-Mod control room. The PC will remotely control the system and store the data in the MDSplus database.

  13. SIRE (sight-integrated ranging equipment): an eyesafe laser rangefinder for armored vehicle fire control systems

    NASA Astrophysics Data System (ADS)

    Keeter, Howard S.; Gudmundson, Glen A.; Woodall, Milton A., II

    1991-04-01

    The Sight Integrated Ranging Equipment (SIRE) incorporates an eyesafe laser rangefinder into the M-36 periscope used in tactical armored vehicles, such as the Commando Stingray light tank. The SIRE unit provides crucial range data simultaneously to the gunner and fire control computer. This capability greatly reduces 'time-to-fire', improves first-round hit probability, and increases the overall effectiveness of the vehicle under actual and simulated battlefield conditions. The SIRE can provide target range up to 10-km, with an accuracy of 10-meters. The key advantage of the SIRE over similar laser rangefinder systems is that it uses erbium:glass as the active lasing medium. With a nominal output wavelength of 1.54-microns, the SIRE can produce sufficient peak power to penetrate long atmospheric paths (even in the presence of obscurants), while remaining completely eyesafe under all operating conditions. The SIRE is the first eyesafe vehicle-based system to combine this level of accuracy, maximum range capability, and fire control interface. It simultaneously improves the accuracy and confidence of the operator, and eliminates the ocular hazard issues typically encountered with laser rangefinder devices.

  14. Head mounted DMD based projection system for natural and prosthetic visual stimulation in freely moving rats

    PubMed Central

    Arens-Arad, Tamar; Farah, Nairouz; Ben-Yaish, Shai; Zlotnik, Alex; Zalevsky, Zeev; Mandel, Yossi

    2016-01-01

    Novel technologies are constantly under development for vision restoration in blind patients. Many of these emerging technologies are based on the projection of high intensity light patterns at specific wavelengths, raising the need for the development of specialized projection systems. Here we present and characterize a novel projection system that meets the requirements for artificial retinal stimulation in rats and enables the recording of cortical responses. The system is based on a customized miniature Digital Mirror Device (DMD) for pattern projection, in both visible (525 nm) and NIR (915 nm) wavelengths, and a lens periscope for relaying the pattern directly onto the animal’s retina. Thorough system characterization and the investigation of the effect of various parameters on obtained image quality were performed using ZEMAX. Simulation results revealed that images with an MTF higher than 0.8 were obtained with little effect of the vertex distance. Increased image quality was obtained at an optimal pupil diameter and smaller field of view. Visual cortex activity data was recorded simultaneously with pattern projection, further highlighting the importance of the system for prosthetic vision studies. This novel head mounted projection system may prove to be a vital tool in studying natural and artificial vision in behaving animals. PMID:27731346

  15. Can SOHO SWAN detect CMEs?

    NASA Technical Reports Server (NTRS)

    St.Cyr, O. C.; Malayeri, M. L.; Yashiro, S.; Quernerais, E.; Bertaux, Jean-Loup; Howard, Russ

    2003-01-01

    We have investigated the possibility that the Solar Wind Anisotropies (SWAN) remote sensing instrument on SOHO may be able to detect coronal mass ejections (CMEs) in neutral Hydrogen Lyman-? emission. We have identified CMEs near the Sun in observations by the SOHO LASCO white-light coronagraphs and in extreme ultraviolet emissions using SOHO E n . There are very few methods of tracking CMEs after they leave the coronagraph's field-of-view, so this is an important topic to study. The primary science goal of the SWAN investigation is the measurement of large-scale structures in the solar wind, and these are obtained by detecting intensity fluctuations in Lyman-?. SWAN consists of a pair of Sensors on opposite panels of SOHO. The instantaneous field-of-view of each sensor unit is a So x So square, divided into lo pixels. A gimbaled periscope system allows each sensor to map the intensity distribution of Lyman-?, and the entire sky can be scanned in less than one day. This is the typical mode of operation for this instrument.

  16. Fast imaging diagnostics on the C-2U advanced beam-driven field-reversed configuration device

    NASA Astrophysics Data System (ADS)

    Granstedt, E. M.; Petrov, P.; Knapp, K.; Cordero, M.; Patel, V.

    2016-11-01

    The C-2U device employed neutral beam injection, end-biasing, and various particle fueling techniques to sustain a Field-Reversed Configuration (FRC) plasma. As part of the diagnostic suite, two fast imaging instruments with radial and nearly axial plasma views were developed using a common camera platform. To achieve the necessary viewing geometry, imaging lenses were mounted behind re-entrant viewports attached to welded bellows. During gettering, the vacuum optics were retracted and isolated behind a gate valve permitting their removal if cleaning was necessary. The axial view incorporated a stainless-steel mirror in a protective cap assembly attached to the vacuum-side of the viewport. For each system, a custom lens-based, high-throughput optical periscope was designed to relay the plasma image about half a meter to a high-speed camera. Each instrument also contained a remote-controlled filter wheel, set between shots to isolate a particular hydrogen or impurity emission line. The design of the camera platform, imaging performance, and sample data for each view is presented.

  17. Evolution of design concepts for remotely maintainable equipment racks

    SciTech Connect

    Peishel, F.L.; Mouring, R.W.; Schrock, S.L.

    1986-01-01

    Equipment racks have been used to support process equipment in radioactive facilities for many years. Improvements in the design of these racks have evolved relatively slowly primarily as a result of limitations in the capabilities of maintenance equipment; that is, tasks could only be approached from above using bridge cranes with viewing primarily through periscopes. In recent years, however, technological advances have been made by the Consolidated Fuel Reprocessing Program (CFRP) at Oak Ridge National Laboratory (ORNL) in bridge-mounted servomanipulators with onboard auxiliary hoists and television viewing systems. These advances permit full cell coverage by the manipulator arms which, in turn, allow maintenance tasks to be approached horizontally as well as from above. Maintainable equipment items can be stacked vertically on a rack because total overhead access is less important and maintenance tasks that would not have been attempted in the past can now be performed. These advances permit greater flexibility in the design and cell layout of the racks and lead to concepts that could significantly increase the availability of a facility. The evolution of rack design and a description of the alternative concepts based on present maintenance systems capabilities are presented in this paper. 13 refs., 11 figs.

  18. Target plane imager for inertial confinement fusion

    SciTech Connect

    Swift, C.D.; Bliss, E.S.; Jones, W.A.; Seppala, L.G.

    1985-01-30

    The Nova laser, completed in December 1984 at Lawrence Livermore National Laboratory, is being used to conduct inertial confinement fusion experiments. It is capable of focusing more than 100 kJ of energy on small fusion targets. This paper discusses an optical system called the target plane imager that is used during the beam alignment phase of these experiments. The TPI includes a three meter long periscope with a wide field of view, F/3 objective. The telescope relays images of the target focal plane to viewing optics and a video sensor located outside the target chamber. Operation of the system is possible at three wavelengths: 1.05..mu.., 0.527..mu.., and 0.351..mu... These are the three wavelengths at which the ten Nova laser beams can irradiate targets. Both nearfield and farfield images of the ten beams can be viewed with the TPI. This instrument is used to properly align the laser to the target before each target irradiation.

  19. Fast Filtered Imaging of the C-2U Advanced Beam-Driven Field-Reversed Configuration

    NASA Astrophysics Data System (ADS)

    Granstedt, E. M.; Petrov, P.; Knapp, K.; Cordero, M.; Patel, V.; the TAE Team

    2015-11-01

    The goal of the C-2U program is to sustain a Field-Reversed Configuration (FRC) for 5+ ms using neutral beam injection, end-biasing, and various particle fueling techniques. Three high-speed, filtered cameras are used to observe visible light emission from deuterium pellet ablation and compact-toroid injection which are used for auxiliary particle fueling. The instruments are also used to view the dynamics of the macroscopic plasma evolution, identify regions of strong plasma-material interactions, and visualize non-axisymmetric perturbations. To achieve the necessary viewing geometry, imaging lenses are mounted in re-entrant viewports, two of which are mounted on bellows for retraction during gettering and removal if cleaning is necessary. Images are coupled from the imaging lens to the camera via custom lens-based optical periscopes. Each instrument contains a remote-controlled filter wheel which is set between shots to select a particular emission line from neutral D or various charge states of He, C, O, or Ti. Measurements of absolute emissivity and estimates of neutral and impurity density will be presented.

  20. The influence of the hand's acceleration and the relative contribution of drag and lift forces in front crawl swimming.

    PubMed

    Gourgoulis, Vassilios; Boli, Alexia; Aggeloussis, Nikolaos; Antoniou, Panagiotis; Toubekis, Argyris; Mavromatis, Georgios

    2015-01-01

    The aim of this study was to assess the effect of the hand's acceleration on the propulsive forces and the relative contribution of the drag and lift on their resultant force in the separate phases of the front crawl underwater arm stroke. Ten female swimmers swam one trial of all-out 25-m front crawl. The underwater motion of each swimmer's right hand was recorded using four camcorders and four periscope systems. Anatomical landmarks were digitised, and the propulsive forces generated by the swimmer's hand were estimated from the kinematic data in conjunction with hydrodynamic coefficients. When the hand's acceleration was taken into account, the magnitude of the propulsive forces was greater, with the exception of the mean drag force during the final part of the underwater arm stroke. The mean drag force was greater than the mean lift force in the middle part, while the mean lift force was greater than the mean drag force in the final part of the underwater arm stroke. Thus, swimmers should accelerate their hands from the beginning of their backward motion, press the water with large pitch angles during the middle part and sweep with small pitch angles during the final part of their underwater arm stroke.

  1. Let's Have a Tweetup: The Case for Using Twitter Professionally.

    PubMed

    Fuller, Maren Y; Allen, Timothy Craig

    2016-09-01

    Social media use is very common and can be an effective way for professionals to discuss information and interact with colleagues. Twitter (Twitter, Inc, San Francisco, California) is a social media network where posts, termed tweets, are limited to 140 characters. Professional use of Twitter is ideal for physicians interested in both networking and education and is optimally used to facilitate in-person networking. Live-tweeting (posting real-time reactions to events) at professional meetings is also a popular and highly successful use of Twitter. Physicians report patient privacy as the top concern preventing use of social media for professional reasons, and although generally social media use is safe, it is essential to understand how to protect patient confidentially. Other social media platforms with potential for professional use include Facebook (Facebook, Inc, Menlo Park, California), Instagram (Facebook, Inc), YouTube (YouTube, LLC, San Bruno, California), and Periscope (Twitter, Inc). With Twitter and other social media options, now is the time for pathologists to increase our visibility on social media and worldwide.

  2. Beryllium Use in the Advanced Test Reactor

    SciTech Connect

    Glen R. Longhurst

    2007-12-01

    The Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) began operation in 1967. It makes use of a unique serpentine fuel core design and a beryllium reflector. Reactor control is achieved with rotating beryllium cylinders to which have been fastened plates of hafnium. Over time, the beryllium develops rather high helium content because of nuclear transmutations and begins to swell. The beryllium must be replaced at nominally 10-year intervals. Determination of when the replacement is made is by visual observation using a periscope to examine the beryllium surface for cracking and swelling. Disposition of the irradiated beryllium was once accomplished in the INL’s Radioactive Waste Management Complex, but that is no longer possible. Among contributing reasons are high levels of specific radioactive contaminants including transuranics. The INL is presently considering disposition pathways for this irradiated beryllium, but presently is storing it in the canal adjacent to the reactor. Numerous issues are associated with this situation including (1) Is there a need for ultra-low uranium material? (2) Is there a need to recover tritium from irradiated beryllium either because this is a strategic material resource or in preparation for disposal? (3) Is there a need to remove activation and fission products from irradiated beryllium? (4) Will there be enough material available to meet requirements for research reactors (fission and fusion)? In this paper will be discussed the present status of considerations on these issues.

  3. Impact of WWI on Relativity and Other Sciences

    NASA Astrophysics Data System (ADS)

    Trimble, Virginia

    2015-04-01

    Custom calls WWII the physicists' war (radar, nuclear bombs, rockets) and WWI the chemists' war (nitrogen fixation and synthetic fuels as well as poison gases). In fact both wars affected all of science profoundly. For us, hostilities began with the capture of Erwin Freundlich's German eclipse expedition to the Crrimea in August 1914. Curioiusly they had gone there to measure deflection of starlight be the sun at the half-of-GR level predicted earlier by Einstein. The end came in 1919 with the founding of the IAU (Central Powers strictly excluded; indeed Germany did not join until after WWII) and the Eddington-Dyson-Crommelin eclipse expedition that did record the deflection. In between were many deaths (Moseley and Karl Schwarzschild perhaps best know), turning of observatory optical shops to making binoculars, periscopes, etc, and twisting of careers (including probably the origin of the Hubble-Shapley enmity, when the former volunteered and the latter went directly to a job at Mt. Wilson; Lemaitre is another interesting case). There will be a small prize for the first person to identify the gentleman who refereed my second thesis paper, who served the full four years, partly in the trenches, on the German side.

  4. Views of parents, teachers and children on health promotion in kindergarten--first results from formative focus groups and observations.

    PubMed

    Sansolios, Sanne; Mikkelsen, Bent Egberg

    2011-10-01

    The aim of the study was to capture the views of children, parents and teachers on the topic of physical activity in kindergarten through observation and focus group interviews. The study was conducted in the kindergartens from the sampling group in the Danish part of PERISCOPE. 1(st) methodology: Children interviewed inside by the researcher on preferable movements and settings and then observed outside during their playtime. 2(nd) methodology: Children asked to draw themselves playing their most preferred physical activity. Parents and kindergarten teachers interviewed in two different groups, using an identical guide. Children are skilled in taking advantage of the space and facilities available for physical activity; girls need more support than boys to initiate physical activity; children are happy with the facilities and the toys available in the kindergarten. Teachers feel an increasing pressure to take more responsibility and initiatives for the children's health habits. Parents state that if more physical activity is initiated in the kindergarten, it could make children request domestic activity. Physical activity and movement concept are too abstract for children of this age to talk about: they quickly lose their focus and concentration. The new methodology of videotaping gives the researcher the chance to interpret facial expressions to capture movement, talk and actions, and to make a distinction among children, as they tend to interrupt each other. However, this method contains a weakness, if used alone, by the fact that the shooting is only a reflection of what the video camera has recorded.

  5. Various uses for optical metamaterials

    NASA Astrophysics Data System (ADS)

    Barbosa, Jose G.

    2015-05-01

    Optical metamaterials promise aberration free and better than diffraction limited performance for imaging systems through constructed materials made to regulate the interaction with electromagnetic waves. Optical metamaterials have the potential to miniaturize the optical bench and obtain diffraction-limited performance with a single device. The reduction of size, weight, and complexity of optical systems while maintaining performance is desired. In unmanned aircrafts, buoy systems, 360 degree imaging systems, and optronic or traditional periscope systems the lenses constitute a considerable percentage of the weight and volume. Another characteristic that is desired is optical cross section reduction for both visible and infrared bands. Optical cloaking using metamaterials has the potential to make objects indiscernible from its environment by masking objects signature. Other characteristics that are desired are materials that are perfect light absorbers for stray light baffles, detectors, or solar energy harvesting, nonlinear frequency conversion for photonics devices, and lenses or head window coatings to achieve specific properties. These topics are discussed in this paper.

  6. Conceptual design study for an advanced cab and visual system, volume 1

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    A conceptual design study was conducted to define requirements for an advanced cab and visual system. The rotorcraft system integration simulator is for engineering studies in the area of mission associated vehicle handling qualities. Principally a technology survey and assessment of existing and proposed simulator visual display systems, image generation systems, modular cab designs, and simulator control station designs were performed and are discussed. State of the art survey data were used to synthesize a set of preliminary visual display system concepts of which five candidate display configurations were selected for further evaluation. Basic display concepts incorporated in these configurations included: real image projection, using either periscopes, fiber optic bundles, or scanned laser optics; and virtual imaging with helmet mounted displays. These display concepts were integrated in the study with a simulator cab concept employing a modular base for aircraft controls, crew seating, and instrumentation (or other) displays. A simple concept to induce vibration in the various modules was developed and is described. Results of evaluations and trade offs related to the candidate system concepts are given, along with a suggested weighting scheme for numerically comparing visual system performance characteristics.

  7. DARWIN nulling interferometer breadboard I: System engineering and measurements

    NASA Astrophysics Data System (ADS)

    Flatscher, Reinhold; Sodnik, Zoran; Ergenzinger, Klaus; Johann, Ulrich; Vink, Rob

    2003-10-01

    The presented work has been funded by ESA under ESTEC/Contract No. 14827/00/NL/CK and Astrium Germany has been awarded with this first ESA breadboarding towards nulling interferometry. Astrium designed and manufactured a nulling breadboard operating in the near infrared. The selected concept is fully transferable to the mid infrared. The interferometer is based on a highly symmetric Sagnac core. A dispersive phase shifter or a periscope system maintains the required phase shift of π. Two different source simulators have been built to test the interferometer's performance. They provide two point sources simulating a typical star and a planet signal. Angular separation of the point sources and intensity can be adapted to both operation modes, nulling and imaging. The OPD is actively stabilized to a gray fringe at a shorter wavelength without wobbling the system's OPD. The best results obtained with a diode laser source were a star suppression of 408,000 and a suppression of 32,000 using a broad-band ASE source. A stable deep null with a star suppression of 50,000 to 70,000 could be achieved over half an hour.

  8. Laser Safety: A Laser Alignment Practical Training Course

    SciTech Connect

    Woods, Michael; Edstrom, Steve; /SLAC

    2011-01-26

    SLAC National Accelerator Laboratory has developed a Laser Alignment Practical Training Course as one of its core laser safety classes. The course is taught to small groups of up to three students and takes 1-3 hours to complete. This practical course is not a substitute for site-specific On-the-Job Training; it does, however, provide a good introduction in core laser safety practices that can be broadly applied. Alignment and diagnostic tasks are performed with low power lasers. Students learn safe alignment and diagnostic techniques and how to avoid common mistakes that might lead to an accident. The class is taught by laser supervisors, enabling them to assess the skill level of new laser personnel and determine the subsequent level of supervision needed. The course has six alignment tasks. For each task, discussion points are given for the instructor to review with the students. The optics setup includes different wavelength lasers, a beam expander, mirrors, irises, a periscope, a beam-splitting polarizer and a diffraction grating. Diagnostic tools include viewing cards, an IR viewer and a ccd camera. Laser eyewear is available to block some laser wavelengths in the setup.

  9. Synthesis and design of silicide intermetallic materials. 1998 annual progress report

    SciTech Connect

    Petrovic, J.J.; Castro, R.G.; Butt, D.P.; Park, Y.; Vaidya, R.U.; Hollis, K.J.; Kung, H.H.

    1999-03-01

    The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the US processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive US processing industries. The program presently has a number of developing industrial connections, including a CRADA with Johns Manville Corporation targeted at the area of MoSi{sub 2}-based high temperature materials and components for fiberglass melting and processing applications. The authors are also developing an interaction with the Institute of Gas Technology (IGT) to develop silicides for high temperature radiant gas burner applications, for the glass and other industries. With Combustion Technology Inc., they are developing silicide-based periscope sight tubes for the direct observation of glass melts. With Accutru International Corporation, they are developing silicide-based protective sheaths for self-verifying temperature sensors which may be used in glass furnaces and other industrial applications. The progress made on the program in this period is summarized.

  10. LG wargaming tool for effect-based operations

    NASA Astrophysics Data System (ADS)

    Stilman, Boris; Yakhnis, Vladimir; McCrabb, Maris

    2002-07-01

    The LG-WGT approach to EBO may be summarized as follows. 1) Causes and Effects will be defined as game state properties. 2) LG algorithms will automatically generate strategies to attain desired effects. The strategies will be generated through LG Zones. LG will model effects as properties of the game pieces and relations among the pieces and the board. 3) The overall Engagement Theater will be modeled as LG hypergame, that is several concurrent abstract board games (ABG) linked together via inter-linking mappings (ILM). LG will represent indirect effects in a related game linked with the game of interest via several ILMs. With LG-WGT, a commander will observe the entire operation as an omnipresent ghost with a virtual camera. He/she would be able to view the operation from the cockcpit of a fighter flying on a SEAD mission, from the cabin of an amphibious vehicle, through the periscope of an attack submarine, or from a virtual AWACS flying over the entire battlefield. Even a normally invisible element, like damages to adversarial infrastructure or political changes, will be made visible in virtual reality together with the chain of events causing this effect. The LG-WGT will provide explanation for all the decisions made employing probabilities of kill, integrated probabilities of survival, threshold for retreat, etc.

  11. Measurements of Fast Ion Transport Due to n = 3 Magnetic Perturbations on DIII-D

    NASA Astrophysics Data System (ADS)

    van Zeeland, M. A.; Evans, T. E.; Ferraro, N. M.; Lanctot, M. J.; Pace, D. C.; Collins, C.; Heidbrink, W. W.; Garcia-Munoz, M.; Hanson, J. M.; Grierson, B. A.; Kramer, G. J.; Nazikian, R.; Allen, S. L.; Lasnier, C. J.; Meyer, W. H.

    2014-10-01

    Measurements of fast ion (FI) transport due to applied n = 3 magnetic perturbations on DIII-D have been made in both ELM suppressed H-mode as well as L-mode discharges. FIDA measurements probe the confined FI profile in the edge and losses to the wall are obtained with scintillator detectors as well as an infrared periscope. In ELM suppressed plasmas FIDA data show a significant depletion of the edge FI profile during application of n = 3 fields. IR imaging of the beam ion prompt loss footprint shows a difference in wall heating depending on phase of the n = 3 perturbation. Measurements of both the impact on the confined FI profile and prompt losses will be compared to full-orbit modeling which predicts up to 10%-15% of the injected beam ions are lost before thermalization. Orbit following simulations also predict an increase in losses due to resonance between the FI drift orbits and the applied n = 3 fields. Measurements during L-mode current ramp plasmas used to scan for signatures of these resonances will be discussed. Work supported in part by the US DOE under DE-FC02-04ER54698, SC-G903402, DE-FG02-04ER54761, DE-AC02-09CH11466, DE-AC52-07NA27344.

  12. Extinction measurements for optical band gap determination of soot in a series of nitrogen-diluted ethylene/air non-premixed flames.

    PubMed

    Adkins, Erin M; Miller, J Houston

    2015-01-28

    Visible light extinction was measured in a series of nitrogen-diluted, ethylene/air, non-premixed flames and this data was used to determine the optical band gap, OBG, as a function of flame position. Collimated light from a supercontinuum source is telescopically expanded and refocused to match the f- number of a dispersing monochromator. The dispersed light is split into a power metering channel and a channel that is periscoped and focused into the flame. The transmitted light is then recollimated and focussed onto a silicon photodiode detector. After tomographic reconstruction of the radial extinction field, the OBG was derived from the near-edge absorption feature using Tauc/Davis-Mott analysis. A slight evolution in OBG was observed throughout all flame systems with a consistent range of OBG observed between approximately 1.85 eV and 2.35 eV. Averaging over all positions the mean OBG was approximately 2.09 eV for all flame systems. Comparing these results to previously published computational results relating calculated HOMO-LUMO gaps for a variety of D2h PAH molecules to the number of aromatic rings in the structure, showed that the observed optical band gap is consistent with a PAH of about 14 rings or a conjugation length of 0.97 nm. This work provides experimental support to the model of soot formation where the transition from chemical to physical growth starts at a modest molecular size; about the size of circumpyrene.

  13. Let's Have a Tweetup: The Case for Using Twitter Professionally.

    PubMed

    Fuller, Maren Y; Allen, Timothy Craig

    2016-09-01

    Social media use is very common and can be an effective way for professionals to discuss information and interact with colleagues. Twitter (Twitter, Inc, San Francisco, California) is a social media network where posts, termed tweets, are limited to 140 characters. Professional use of Twitter is ideal for physicians interested in both networking and education and is optimally used to facilitate in-person networking. Live-tweeting (posting real-time reactions to events) at professional meetings is also a popular and highly successful use of Twitter. Physicians report patient privacy as the top concern preventing use of social media for professional reasons, and although generally social media use is safe, it is essential to understand how to protect patient confidentially. Other social media platforms with potential for professional use include Facebook (Facebook, Inc, Menlo Park, California), Instagram (Facebook, Inc), YouTube (YouTube, LLC, San Bruno, California), and Periscope (Twitter, Inc). With Twitter and other social media options, now is the time for pathologists to increase our visibility on social media and worldwide. PMID:27195434

  14. Visual Target Tracking in the Presence of Unknown Observer Motion

    NASA Technical Reports Server (NTRS)

    Williams, Stephen; Lu, Thomas

    2009-01-01

    Much attention has been given to the visual tracking problem due to its obvious uses in military surveillance. However, visual tracking is complicated by the presence of motion of the observer in addition to the target motion, especially when the image changes caused by the observer motion are large compared to those caused by the target motion. Techniques for estimating the motion of the observer based on image registration techniques and Kalman filtering are presented and simulated. With the effects of the observer motion removed, an additional phase is implemented to track individual targets. This tracking method is demonstrated on an image stream from a buoy-mounted or periscope-mounted camera, where large inter-frame displacements are present due to the wave action on the camera. This system has been shown to be effective at tracking and predicting the global position of a planar vehicle (boat) being observed from a single, out-of-plane camera. Finally, the tracking system has been extended to a multi-target scenario.

  15. Performance characteristics of a submarine panoramic infrared imaging sensor

    NASA Astrophysics Data System (ADS)

    Nichols, J. M.; Waterman, J. R.; Menon, Raghu; Devitt, John

    2010-04-01

    A high-resolution mid-wave infrared panoramic periscope sensor system has been developed. The sensor includes a catadioptric optical system that provides a 360° horizontal azimuth by -10° to +30° elevation field of view without requiring moving components (e.g. rotating mirrors). The focal plane is a 2048 x 2048, 15μm pitch InSb detector operating at 80K. An on-board thermo-electric reference source allows for real-time nonuniformity correction using the two-point correction method. The entire system (detector-dewar assembly, cooler, electronics and optics) is packaged to fit in an 8" high, 6.5" diameter volume. This work describes both the system optics and electronics and presents sample imagery. We also discuss the sensor's radiometric performance, quantified by the NEDT, as a function of key system parameters. The ability of the system to resolve targets as a function of imaged spatial frequency is also presented.

  16. Influence of Spinel head window thickness on the performance characteristics of a submarine panoramic infrared imaging system

    NASA Astrophysics Data System (ADS)

    Nichols, Jonathan M.; Waterman, Jim R.; Bayya, Shyam; Sanghera, Jas S.; Aggarwal, Ish D.

    2011-06-01

    This work explores the influence of head window thickness on the performance of a mid-wave infrared, panoramic periscope imager. Our focus is on transparent spinel ceramic as the head window material. Spinel is an attractive material for IR applications due to its good strength and transmission properties (visible through mid-wave). However, there is some degradation in spinel transmission near the high end of the mid-wave band ( 5μm) as the head window thickness increases. In this work we predict the relationship between head window thickness and imager performance, as quantified by the Noise Equivalent Temperature Difference, and compare these predictions to values estimated from experimental data. We then discuss the implications for imager design and demonstrate a possible approach to correcting for the headwindow-induced losses. The imager used in this study is a compact, catadioptric, camera that provides a 360o horizontal azimuth by -10o to +30o elevation field of view and uses a 2048 x 2048, 15μm pitch InSb detector.

  17. Statis omnidirectional stereoscopic display system

    NASA Astrophysics Data System (ADS)

    Barton, George G.; Feldman, Sidney; Beckstead, Jeffrey A.

    1999-11-01

    A unique three camera stereoscopic omnidirectional viewing system based on the periscopic panoramic camera described in the 11/98 SPIE proceedings (AM13). The 3 panoramic cameras are equilaterally combined so each leg of the triangle approximates the human inter-ocular spacing allowing each panoramic camera to view 240 degree(s) of the panoramic scene, the most counter clockwise 120 degree(s) being the left eye field and the other 120 degree(s) segment being the right eye field. Field definition may be by green/red filtration or time discrimination of the video signal. In the first instance a 2 color spectacle is used in viewing the display or in the 2nd instance LCD goggles are used to differentiate the R/L fields. Radially scanned vidicons or re-mapped CCDs may be used. The display consists of three vertically stacked 120 degree(s) segments of the panoramic field of view with 2 fields/frame. Field A being the left eye display and Field B the right eye display.

  18. A geodetic laser radar rangefinder with 10(exp -7) resolution

    NASA Technical Reports Server (NTRS)

    Mizushima, Y.; Takeichi, M.; Warashima, Y.; Takeshima, A.; Ogawa, I.; Ichie, K.; Schiller, N. H.

    1992-01-01

    A novel geodetic laser radar rangefinder (GLRR) unit utilizing a pair of synchronized 10-psec streak camera systems was developed for displacement measurements of the earth's plates. In order to achieve minimum computing error and assure extremely high spatial resolution, an optical pulse registration clock was developed and used to register a fiducial mark on the time scale of the system. Conventional optical rangefinders have been limited to a relative resolution of 10(exp -6) even for short distances. The system to be reported on today has the capability of measuring a 50km range with an accuracy of 4mm corresponding to a relative resolution of 10(exp -7). With a gain of greater than 3 x 10(exp 3), the system has the capability of detecting extremely weak signals on the order of photon counting. This combined with temporal gating makes daytime measurements comparable in signal-to-noise ratio to nighttime viewing. This is useful for measuring faint signals returning over a range of several tens of kilometers. The present ranging system was designed to observe the mutual displacement of geodetic plates and was employed to measure the boundary between the Philippine and Asian geodetic plates that pass beneath the Suruga Bay near Hamamatsu City, Japan. The system has been in operation for over 3 years. In addition, the system has the ability of producing and detecting optical ranging pulses of several wavelengths simultaneously, making this a complete multicolor system. The basic GLRR system consists of a frequency stabilizing crystal, optical clock, YAG laser, KDP doubling crystal, DK*P tripling crystal, two matched streak cameras (A and B), a control computer, and an output/input periscope system.

  19. Anomalous phase shifts in drift wave fluctuations

    NASA Astrophysics Data System (ADS)

    Diallo, Ahmed; Skiff, Fred

    2003-10-01

    Ion phase space density fluctuation measurements are performed in a linearly magnetized device using Laser Induced Fluorescence(LIF). An ICP source produces an 8cm diameter plasma column that drifts in a cylindrical vessel whose diameter and length are 40 cm and 3 m, respectively. These experiments are performed using a CW singly ionized Argon plasma that is immersed in a 1kG magnetic field along the axis of the cylinder. A density of the order of 10^9 cm-3 is obtained under a regulated neutral background pressure of 2.× 10-4 torr. The electron and ion temperature are respectively 2 eV and 0.1 eV. LIF is carried out by pumping the Ar II metastable (3d^1)^2G_9/2, using a CW tunable laser centered at 611.6653 nm scanned over 6 GHz, to metastable (4p^1)F_7/2, and then detecting the 460nm photons emitted from its transition to (4s^1)^2F_5/2. This collection is made possible using two low f-umber periscopes that are directed to PMTs. Here we present measurements of the complex two-point correlation function < f(v_i_allel),z_1,ω)f(v_i_allel,z_2,ω)> as a function of the spatial separation of two LIF detection systems Δ d = z_2-z_1, the ion parallel velocity v_i_allel and the frequency ω. Preliminary results show ion particle velocity dependent phase shifts at the drift wave frequency.

  20. Atomically Bonded Transparent Superhydrophobic Coatings

    SciTech Connect

    Aytug, Tolga

    2015-08-01

    Maintaining clarity and avoiding the accumulation of water and dirt on optically transparent surfaces such as US military vehicle windshields, viewports, periscope optical head windows, and electronic equipment cover glasses are critical to providing a high level of visibility, improved survivability, and much-needed safety for warfighters in the field. Through a combination of physical vapor deposition techniques and the exploitation of metastable phase separation in low-alkali borosilicate, a novel technology was developed for the fabrication of optically transparent, porous nanostructured silica thin film coatings that are strongly bonded to glass platforms. The nanotextured films, initially structurally superhydrophilic, exhibit superior superhydrophobicity, hence antisoiling ability, following a simple but robust modification in surface chemistry. The surfaces yield water droplet contact angles as high as 172°. Moreover, the nanostructured nature of these coatings provides increased light scattering in the UV regime and reduced reflectivity (i.e., enhanced transmission) over a broad range of the visible spectrum. In addition to these functionalities, the coatings exhibit superior mechanical resistance to abrasion and are thermally stable to temperatures approaching 500°C. The overall process technology relies on industry standard equipment and inherently scalable manufacturing processes and demands only nontoxic, naturally abundant, and inexpensive base materials. Such coatings, applied to the optical components of current and future combat equipment and military vehicles will provide a significant strategic advantage for warfighters. The inherent self-cleaning properties of such superhydrophobic coatings will also mitigate biofouling of optical windows exposed to high-humidity conditions and can help decrease repair/replacement costs, reduce maintenance, and increase readiness by limiting equipment downtime.

  1. Development of imaging bolometers for long-pulse MFE experiments (invited)

    SciTech Connect

    Wurden, G.A.; Peterson, B.J.

    1999-01-01

    We have developed the concept of an imaging bolometer, capable of operation with 100{close_quote}s of individual channels, while relying on optical (infrared) readout of the temperature rise in a thin foil. A thin gold foil (0.5{endash}5 {mu}m thick) is sandwiched between pieces of copper. The copper mask (a large thermal mass) has a hole pattern drilled into it to form many {open_quotes}individual pixels,{close_quotes} effectively forming many separate sensors. This segmented foil/mask combination is exposed on its front side to plasma radiation through a cooled pinhole camera geometry. Simultaneously, a high-resolution infrared camera monitors any temperature change on the backside of the thin foil. A sensitive infrared (IR) camera views the foil through an IR telescope/periscope system, and is shielded from the magnetic and nuclear radiation fields, either by distance and/or material shielding. A simple time-dependent design algorithm, using 1D heat transport to a cold boundary, has been written in MathCad, which allows us to select optimal material and geometries to match the expected plasma conditions. We have built a compact prototype with 149 channels, and tested it successfully both in a vacuum test stand in the laboratory, and on a plasma in the CHS at the National Institute for Fusion Science, subjecting it to electron cyclotron heated and neutral beam injection heated conditions. A water-cooled version has been built for the new LHD. Since the IR imaging bolometer uses only metal parts near the plasma, and has no need for wiring or wiring feedthrus, it is intrinsically radiation hard, and has direct application to ignition device to test engineering concepts (ITER), or ITER-class experiments. {copyright} {ital 1999 American Institute of Physics.}

  2. A study of the Northern polar region of the sun using the microwave observations of the total eclipse of March 29, 2006

    NASA Astrophysics Data System (ADS)

    Bogod, V. M.; Golubchina, O. A.; Zhekanis, G. N.; Korzhavin, A. N.; Kotel'Nikov, V. S.; Nizhel'Skij, N. A.; Tsybulev, P. G.

    2007-12-01

    We report the results of unique observations of the solar eclipse of March 29, 2006 over a wide radio-wavelength range from 1 to 50 cm made with the large RATAN-600 stationary radio telescope during the maximum eclipse phase performed using the method of the source transit across the fixed beam pattern. The multifunctional opportunities of the radio telescope allowed observations to be performed simultaneously in a part of the Northern sector of RATAN-600 and in the Southern-sector plus periscope mode using all the available receiving equipment at the corresponding secondary mirrors. At the time of maximum eclipse phase a narrow 1—3-arcsec wide crescent-shaped band near the North Solar Pole remained visible out of the entire solar disk covered by the Moon. We achieved high flux sensitivity, which allowed us to discover a large polar radio source located above the North Solar Pole and obtain detailed data on its radiation and spatial structure. Moreover, we detected optically thin radiation of the solar corona at the brightness-temperature level of several K or several tens of K. We find this radiation to extend beyond the solar limb out to the heliocentric distances of one solar radius. These data are unique in that they are not contaminated by scattered radiation of the solar radio disk, which usually shows up in ordinary observations. We are the first to obtain a detailed spectrum of the radiation of a high-latitude prominence at many wavelengths with a 1% frequency resolution in the microwave range, which allowed us to estimate its magnetic field at a number of levels in the lower corona.

  3. Nest Site Selection by Kentish Plover Suggests a Trade-Off between Nest-Crypsis and Predator Detection Strategies

    PubMed Central

    Gómez-Serrano, Miguel Ángel; López-López, Pascual

    2014-01-01

    Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator) decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of coastal regression

  4. Nest site selection by Kentish plover suggests a trade-off between nest-crypsis and predator detection strategies.

    PubMed

    Gómez-Serrano, Miguel Ángel; López-López, Pascual

    2014-01-01

    Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator) decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of coastal regression

  5. Relative abundances of methane- and sulfur-oxidizing symbionts in gills of the deep-sea hydrothermal vent mussel Bathymodiolus azoricus under pressure

    NASA Astrophysics Data System (ADS)

    Szafranski, Kamil M.; Piquet, Bérénice; Shillito, Bruce; Lallier, François H.; Duperron, Sébastien

    2015-07-01

    The deep-sea mussel Bathymodiolus azoricus dominates hydrothermal vent fauna in the Azores region. The gills of this species house methane- and sulfur-oxidizing bacteria that fulfill most of the mussel's nutritional requirements. Previous studies suggested that the ratio between methane- and sulfur-oxidizers could vary in response to the availability of electron donors in their environment, and this flexibility is considered a key factor in explaining the ecological success of the species. However, previous studies were based on non-isobaric recovery of specimens, with experiments at atmospheric pressure which may have induced artifacts. This study investigates the effect of pressure-related stress during recovery and experimentation on the relative abundances of bacterial symbionts. Mussel specimens were recovered for the first time using the pressure-maintaining device PERISCOP. Specimens were subsequently transferred into pressurized vessels and exposed to various chemical conditions. Using optimized fluorescence in situ hybridization-based approaches, relative abundance of symbionts were measured. Our results show that the recovery method (isobaric versus non-isobaric) does not influence the abundances of bacterial symbionts. Significant differences occur among specimens sampled from two contrasting sites. Exposure of mussels from the deeper site to sulfide and bicarbonate, and to bicarbonate alone, both resulted in a rapid and significant increase in the relative abundance of sulfur-oxidizers. Results reported herein are congruent with those from previous reports investigating mussels originating from shallow sites and kept at ambient pressure. Isobaric recovery and maintenance allowed us to perform in vivo experiments in specimens from a deeper site that could not be maintained alive at ambient pressure, and will greatly improve the chances of identifying the molecular mechanisms underlying the dialogue between bathymodioline hosts and symbionts.

  6. Synthesis and Design of Silicide Intermetallic Materials

    SciTech Connect

    Petrovic, J.J.; Castro, R.G.; Vaidya, R.U.; Park, Y.

    1999-05-14

    The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the US processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive US processing industries. The program presently has a number of industrial connections, including a CRADA with Johns Manville Corporation targeted at the area of MoSi{sub 2}-based high temperature materials for fiberglass melting and processing applications. The authors are also developing an interaction with the Institute of Gas Technology (IGT) to develop silicides for high temperature radiant gas burner applications, for the glass and other industries. With the Exotherm Corporation, they are developing advanced silicide powders for the fabrication of silicide materials with tailored and improved properties for industrial applications. In October 1998, the authors initiated a new activity funded by DOE/OIT on ``Molybdenum Disilicide Composites for Glass Processing Sensors''. With Accutru International Corporation, they are developing silicide-based protective sheaths for self-verifying temperature sensors which may be used in glass furnaces and other industrial applications. With Combustion Technology Inc., they are developing silicide-based periscope sight tubes for the direct observation of glass melts.

  7. Manufacturer evaluations of endograft modifications.

    PubMed

    Waninger, Matthew S; Whirley, Robert G; Smith, Louis J; Wolf, Ben S

    2013-03-01

    The motivation to modify the design of a vascular device can arise from a number of sources. Clinical experience with the unmodified device could suggest new design modifications to improve device performance or clinical outcomes. Similarly, clinical success with a device often suggests modifications that could broaden the applicability of the device to enable treatment of different or more advanced disease states. As a specific example, both of these scenarios have arisen during the last decade in the evolution of endovascular grafts for the treatment of abdominal aortic aneurysms, with modifications enabling the treatment of patients with shorter infrarenal necks, more angulated anatomy, and smaller access vessels. These modifications have been made by manufacturers and additionally by physicians who create branched and fenestrated devices. The experience to date with the use of fenestrated devices and the development of chimney, snorkel, and periscope techniques suggests that modifications to off-the-shelf devices may provide some clinical benefit. This experience provides additional motivation for manufacturers to develop devices to address the clinical needs not met with their current product lines. For manufacturers, the device development process includes an assessment of the new device design to determine the appropriate evaluation strategy to support the safety and effectiveness of the modified device. This report provides a high-level overview of the process generally followed by device manufacturers to evaluate a proposed device modification before market release, in accordance with local country regulations and recognized international standards such as the International Organization of Standardization (ISO) standards for endovascular grafts (ISO 25539 Part 1).

  8. Manufacturer evaluations of endograft modifications.

    PubMed

    Waninger, Matthew S; Whirley, Robert G; Smith, Louis J; Wolf, Ben S

    2013-03-01

    The motivation to modify the design of a vascular device can arise from a number of sources. Clinical experience with the unmodified device could suggest new design modifications to improve device performance or clinical outcomes. Similarly, clinical success with a device often suggests modifications that could broaden the applicability of the device to enable treatment of different or more advanced disease states. As a specific example, both of these scenarios have arisen during the last decade in the evolution of endovascular grafts for the treatment of abdominal aortic aneurysms, with modifications enabling the treatment of patients with shorter infrarenal necks, more angulated anatomy, and smaller access vessels. These modifications have been made by manufacturers and additionally by physicians who create branched and fenestrated devices. The experience to date with the use of fenestrated devices and the development of chimney, snorkel, and periscope techniques suggests that modifications to off-the-shelf devices may provide some clinical benefit. This experience provides additional motivation for manufacturers to develop devices to address the clinical needs not met with their current product lines. For manufacturers, the device development process includes an assessment of the new device design to determine the appropriate evaluation strategy to support the safety and effectiveness of the modified device. This report provides a high-level overview of the process generally followed by device manufacturers to evaluate a proposed device modification before market release, in accordance with local country regulations and recognized international standards such as the International Organization of Standardization (ISO) standards for endovascular grafts (ISO 25539 Part 1). PMID:23446123

  9. Upper extremity kinematics and body roll during preferred-side breathing and breath-holding front crawl swimming.

    PubMed

    Payton, C J; Bartlett, R M; Baltzopoulos, V; Coombs, R

    1999-09-01

    Front crawl swimmers often restrict the number of breaths they take during a race because of the possible adverse effects of the breathing action on resistance or stroke mechanics. The aim of this study was to determine whether differences exist in the kinematics of the trunk and upper extremity used during preferred-side breathing and breath-holding front crawl swimming. Six male swimmers performed trials at their 200 m race pace under breathing and breath-holding conditions. The underwater arm stroke was filmed from the front and side using video cameras suspended over periscope systems. Video recordings were digitized at 50 Hz and the three-dimensional coordinates of the upper extremity obtained using a direct linear transformation algorithm. Body roll angles were obtained by digitizing video recordings of a balsa wood fin attached to the swimmers' backs. The swimmers performed the breathing action without any decrement in stroke length (mean +/- s: breathing 2.24 +/- 0.27 m; breath-holding 2.15 +/- 0.22 m). Stroke widths were similar in the breathing (0.28 +/- 0.07 m) and breath-holding (0.27 +/- 0.07 m) trials, despite swimmers rolling further when taking a breath (66 +/- 5 degrees) than when not (57 +/- 4 degrees). The timing of the four underwater phases of the stroke was also unaffected by the breathing action, with swimmers rolling back towards the neutral position during the insweep phase. In conclusion, the results suggest that front crawl swimmers can perform the breathing action without it interfering with their basic stroke parameters. The insweep phase of the stroke assists body roll and not vice versa as suggested in previous studies.

  10. Active beam spectroscopy for ITER

    NASA Astrophysics Data System (ADS)

    von Hellermann, M. G.; Barnsley, R.; Biel, W.; Delabie, E.; Hawkes, N.; Jaspers, R.; Johnson, D.; Klinkhamer, F.; Lischtschenko, O.; Marchuk, O.; Schunke, B.; Singh, M. J.; Snijders, B.; Summers, H. P.; Thomas, D.; Tugarinov, S.; Vasu, P.

    2010-11-01

    Since the first feasibility studies of active beam spectroscopy on ITER in 1995 the proposed diagnostic has developed into a well advanced and mature system. Substantial progress has been achieved on the physics side including comprehensive performance studies based on an advanced predictive code, which simulates active and passive features of the expected spectral ranges. The simulation has enabled detailed specifications for an optimized instrumentation and has helped to specify suitable diagnostic neutral beam parameters. Four ITER partners share presently the task of developing a suite of ITER active beam diagnostics, which make use of the two 0.5 MeV/amu 18 MW heating neutral beams and a dedicated 0.1 MeV/amu, 3.6 MW diagnostic neutral beam. The IN ITER team is responsible for the DNB development and also for beam physics related aspects of the diagnostic. The RF will be responsible for edge CXRS system covering the outer region of the plasma (1> r/ a>0.4) using an equatorial observation port, and the EU will develop the core CXRS system for the very core (0< r/ a<0.7) using a top observation port. Thus optimum radial resolution is ensured for each system with better than a/30 resolution. Finally, the US will develop a dedicated MSE system making use of the HNBs and two equatorial ports. With appropriate modification, these systems could also potentially provide information on alpha particle slowing-down features. . On the engineering side, comprehensive preparations were made involving the development of an observation periscope, a neutron labyrinth optical system and design studies for remote maintenance including the exchange of the first mirror assembly, a critical issue for the operation of the CXRS diagnostic in the harsh ITER environment. Additionally, an essential change of the orientation of the DNB injection angle and specification of suitable blanket aperture has been made to avoid trapped particle damage to the first wall.

  11. High-Power Prismatic Devices for Oblique Peripheral Prisms

    PubMed Central

    Peli, Eli; Bowers, Alex R.; Keeney, Karen; Jung, Jae-Hyun

    2016-01-01

    ABSTRACT Purpose Horizontal peripheral prisms for hemianopia provide field expansion above and below the horizontal meridian; however, there is a vertical gap leaving the central area (important for driving) without expansion. In the oblique design, tilting the bases of both prism segments toward the horizontal meridian moves the field expansion area vertically and centrally (closing the central gap) while the prisms remain in the peripheral location. However, tilting the prisms results also in a reduction of the lateral field expansion. Higher prism powers are needed to counter this effect. Methods We developed, implemented, and tested a series of designs aimed at increasing the prism power to reduce the central gap while maintaining wide lateral expansion. The designs included inserting the peripheral prisms into carrier lenses that included yoked prism in the opposite direction, combination of two Fresnel segments attached at the base and angled to each other (bi-part prisms), and creating Fresnel prism–like segments from nonparallel periscopic mirror pairs (reflective prisms). Results A modest increase in lateral power was achieved with yoked-prism carriers. Bi-part combination of 36Δ Fresnel segments provided high power with some reduction in image quality. Fresnel reflective prism segments have potential for high power with superior optical quality but may be limited in field extent or by interruptions of the expanded field. Extended apical scotomas, even with unilateral fitting, may limit the utility of very high power prisms. The high-power bi-part and reflective prisms enable a wider effective eye scanning range (more than 15 degrees) into the blind hemifield. Conclusions Conventional prisms of powers higher than the available 57Δ are limited by the binocular impact of a wider apical scotoma and a reduced effective eye scanning range to the blind side. The various designs that we developed may overcome these limitations and find use in various other

  12. Thiazolidinediones: effects on the development and progression of type 2 diabetes and associated vascular complications.

    PubMed

    Krentz, Andrew

    2009-02-01

    In addition to reducing hyperglycaemia, the metabolic actions of TZDs (pioglitazone and rosiglitazone) in theory might improve the prognosis of patients with type 2 diabetes. However, it appears from recent data that pioglitazone and rosiglitazone have different cardiovascular risk profiles. The scope of this paper is to examine the benefits and risks of pioglitazone and rosiglitazone. Three large clinical studies (DREAM, and ADOPT with rosiglitazone; PROactive with pioglitazone) have recently been reported. A lower annual rate of decline of ss-cell function observed with rosiglitazone in the ADOPT study, compared with metformin and glyburide (glibenclamide), along with a reduced progression to insulin use seen with pioglitazone in the PROactive study, provides evidence that TZDs are effective in treating progressive hyperglycaemia. In PROactive, although the primary endpoint was not met, pioglitazone was associated with a reduction in a secondary composite endpoint of clinical cardiovascular events in high-risk patients with existing macrovascular disease who were already receiving other glycaemic and cardiovascular medications. Further evidence supporting an anti-atherogenic effect of pioglitazone was gained from the PERISCOPE study of carotid intima-media thickness. Recent controversy concerning a possible increased risk of myocardial infarction associated with rosiglitazone has fuelled uncertainty about the risk-benefit profile of this agent. In 2008, an update of an American Diabetes Association-European Association for the Study of Diabetes consensus statement on initiation and adjustment of therapy in patients with type 2 diabetes advised clinicians against using rosiglitazone. Skeletal fractures have recently emerged as a side effect of both TZDs. Available data suggest that cardiovascular benefits observed with pioglitazone might not be a class effect of TZDs. PMID:19219860

  13. RoboLab and virtual environments

    NASA Technical Reports Server (NTRS)

    Giarratano, Joseph C.

    1994-01-01

    A useful adjunct to the manned space station would be a self-contained free-flying laboratory (RoboLab). This laboratory would have a robot operated under telepresence from the space station or ground. Long duration experiments aboard RoboLab could be performed by astronauts or scientists using telepresence to operate equipment and perform experiments. Operating the lab by telepresence would eliminate the need for life support such as food, water and air. The robot would be capable of motion in three dimensions, have binocular vision TV cameras, and two arms with manipulators to simulate hands. The robot would move along a two-dimensional grid and have a rotating, telescoping periscope section for extension in the third dimension. The remote operator would wear a virtual reality type headset to allow the superposition of computer displays over the real-time video of the lab. The operators would wear exoskeleton type arms to facilitate the movement of objects and equipment operation. The combination of video displays, motion, and the exoskeleton arms would provide a high degree of telepresence, especially for novice users such as scientists doing short-term experiments. The RoboLab could be resupplied and samples removed on other space shuttle flights. A self-contained RoboLab module would be designed to fit within the cargo bay of the space shuttle. Different modules could be designed for specific applications, i.e., crystal-growing, medicine, life sciences, chemistry, etc. This paper describes a RoboLab simulation using virtual reality (VR). VR provides an ideal simulation of telepresence before the actual robot and laboratory modules are constructed. The easy simulation of different telepresence designs will produce a highly optimum design before construction rather than the more expensive and time consuming hardware changes afterwards.

  14. POLVSM (Polarized Volume Scattering Meter) instrument: an innovative device to measure the directional and polarized scattering properties of hydrosols.

    PubMed

    Chami, Malik; Thirouard, Alexandre; Harmel, Tristan

    2014-10-20

    An innovative instrument dedicated to the multispectral measurements of the directional and polarized scattering properties of the hydrosols, so-called POLVSM, is described. The instrument could be used onboard a ship, as a benchtop instrument, or at laboratory. The originality of the POLVSM concept relies on the use of a double periscopic optical system whose role is (i) to separate the plane containing the light source from the scattering plane containing the sample and the receiver and (ii) to prevent from any specularly reflected light within the sample chamber. As a result, a wide range of scattering angle, namely from 1° to 179°, is covered by the detector. Another originality of the instrument is to measure the Mueller scattering matrix elements, including the degree of polarization. A relevant calibration procedure, which could be of great interest as well for other instruments, is proposed to convert the raw data into physical units. The relative uncertainty in POLVSM data was determined at ± 4.3%. The analysis of measurements of the volume scattering function and degree of polarization performed under controlled conditions for samples dominated either by inorganic hydrosols or phytoplankton monospecific species showed a good consistency with literature, thus confirming the good performance of the POLVSM device. Comparisons of POLVSM data with theoretical calculations showed that Mie theory could reproduce efficiently the measurements of the VSF and degree of polarization for the case of inorganic hydrosols sample, despite the likely non sphericity of these particles as revealed by one of the element of the Mueller matrix. Our results suggested as well that a sophisticated modeling of the heterogeneous internal structure of living cells, or at least, the use of layered sphere models, is needed to correctly predict the directional and polarized effects of phytoplankton on the oceanic radiation. The relevance of performing angularly resolved measurements

  15. Investigating the possibility of a monitoring fast ion diagnostic for ITER.

    PubMed

    De Angelis, R; von Hellermann, M G; Orsitto, F P; Tugarinov, S

    2008-10-01

    In burning plasma fusion devices, fast ion transport plays a central role in the performances of the machines. Moreover the losses of energetic particles might cause severe damages on plasma facing components. Therefore real time measurements of fast ion transport would provide valuable information for safe and reliable plasma operations. In this paper, we examine the feasibility of a monitoring system based on active charge exchange recombination spectroscopy making use of the 0.5 MeV/amu ITER heating neutral beams for detecting fast (4)He(+2) (alphas) particles in ITER plasmas. There are two time scales relevant to fast ion dynamics: the first is the slowing down time of the distribution function which is of the order of 1 s, and the second is the time scale of burstlike transport events such as collective Alfven mode excitations, which--for typical ITER plasma parameters--can be as low as 0.2-1 ms. To detect such fast events a broadband high-throughput spectrometer is needed, while for the reconstruction of the alpha velocity distribution function a higher resolution spectrometer and longer integration time are necessary. To monitor a spatial redistribution of fast particles due to the propagation of the instability, it is proposed to use a limited number of spatial channels, looking at the charge exchange He II spectra induced by the heating beams, whose energy matches the slowing down energies of fast particles. The proposal is to share the motional stark effect periscope on equatorial port 3 [A. Malaquias et al., Rev. Sci. Instrum. 75, 3393 (2004)] adding additional fibers and suitable instruments. A signal to noise ratio of 5 could be achieved with a spatial resolution of a/15 and a time resolution of 5 ms, in a broad spectral band of 100 A, corresponding to the spectral broadening of the line emitted by alpha particles with energies DeltaE < or = 1.5 MeV. Fast H and D ion populations created by heating neutral beam or ion cyclotron resonance heating are

  16. Detection of ethene and other hydrocarbons in gas turbine engine exhaust using non-intrusive FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Arrigone, Giovanni M.; Welch, Michael A.; Hilton, Moira; Miller, Michael N.; Wilson, Christopher W.

    2003-04-01

    As part of the EU funded project AEROJET2, a number of gas turbine engine tests were performed in different facilities around Europe. At Farnborough, UK a Spey engine was used to test a suite of prototype optically based instrumentation designed to measure exhaust gas emissions without using extractive probe systems. In addition to the AEROJET 2 prototype instrumentation, a Bruker Equinox 55 Fourier transform infrared (FTIR) spectrometer was used to obtain infrared spectra of the exhaust plume both in emission and absorption mode. The Bruker FTIR spectrometer was fitted with a periscope system so that different lines of sight could be monitored in the plume in a vertical plane 25 cm downstream from the nozzle exit and 20 cm upstream of the center line of sight of the AEROJET 2 prototype instrumentation. DERA (now QinetiQ) provided exhaust gas analysis data for different engine running conditions using samples extracted from the plume with an intrusive probe. The probe sampled along a horizontal plane across the centerline of the engine 45 cm downstream of the nozzle exit. The Bruker spectrometer used both InSb (indium antimonide) and MCT (mercury-cadmium-telluride) detectors to maximize the sensitivity across the IR range 600-4000 cm-1. Typically, CO2 and H2O IR signatures dominate the observed spectra of the plume. However, the engine tests showed that at low power engine conditions spectral features associated with CO around 2147 cm-1 and with hydrocarbons could be observed at around 3000 cm-1. In particular the presence of ethene (C2H2) was detected from observation of its characteristic in and out of plane vibration mode at 949 cm-1. At high engine powers the presence of NO was detected at 1900.3 cm-1. Species concentrations were calculated using a slab model for each line of sight compared against reference spectra. The engine plume was assumed to be symmetric about the centerline. On this basis, data from the extractive sampling gas analysis that had been

  17. Fast ion transport during applied 3D magnetic perturbations on DIII-D

    NASA Astrophysics Data System (ADS)

    Van Zeeland, M. A.; Ferraro, N. M.; Grierson, B. A.; Heidbrink, W. W.; Kramer, G. J.; Lasnier, C. J.; Pace, D. C.; Allen, S. L.; Chen, X.; Evans, T. E.; García-Muñoz, M.; Hanson, J. M.; Lanctot, M. J.; Lao, L. L.; Meyer, W. H.; Moyer, R. A.; Nazikian, R.; Orlov, D. M.; Paz-Soldan, C.; Wingen, A.

    2015-07-01

    Measurements show fast ion losses correlated with applied three-dimensional (3D) fields in a variety of plasmas ranging from L-mode to resonant magnetic perturbation (RMP) edge localized mode (ELM) suppressed H-mode discharges. In DIII-D L-mode discharges with a slowly rotating n=2 magnetic perturbation, scintillator detector loss signals synchronized with the applied fields are observed to decay within one poloidal transit time after beam turn-off indicating they arise predominantly from prompt loss orbits. Full orbit following using M3D-C1 calculations of the perturbed fields and kinetic profiles reproduce many features of the measured losses and points to the importance of the applied 3D field phase with respect to the beam injection location in determining the overall impact on prompt beam ion loss. Modeling of these results includes a self-consistent calculation of the 3D perturbed beam ion birth profiles and scrape-off-layer ionization, a factor found to be essential to reproducing the experimental measurements. Extension of the simulations to full slowing down timescales, including fueling and the effects of drag and pitch angle scattering, show the applied n=3 RMPs in ELM suppressed H-mode plasmas can induce a significant loss of energetic particles from the core. With the applied n=3 fields, up to 8.4% of the injected beam power is predicted to be lost, compared to 2.7% with axisymmetric fields only. These fast ions, originating from minor radii ρ >0.7 , are predicted to be primarily passing particles lost to the divertor region, consistent with wide field-of-view infrared periscope measurements of wall heating in n=3 RMP ELM suppressed plasmas. Edge fast ion {{\\text{D}}α} (FIDA) measurements also confirm a large change in edge fast ion profile due to the n=3 fields, where the effect was isolated by using short 50 ms RMP-off periods during which ELM suppression was maintained yet the fast ion profile was allowed to recover. The role of resonances

  18. Arterial Stiffness and Trace Elements in Apparently Healthy Population- A Cross-sectional Study

    PubMed Central

    Subrahmanyam, Gangapatnam; Ramalingam, Krishnan; Indira, Selvam Armugam; Kantha, Katari; Soren, Bhemasen

    2016-01-01

    Introduction Stiffening of arteries is a natural ageing process. Any diseases/disorders or risk factors that escalate oxidative stress, microvascular inflammation and endothelial damage may promote to premature vascular stiffening. Any imbalance in these trace element levels may independently contribute to the changes in the components in the arterial wall and thus, arterial stiffness via one or more mechanisms. Aim To evaluate the severity of arterial stiffness in apparently healthy population and also to evaluate role of various risk factors and trace elements in the severity of arterial stiffness Materials and Methods Male and female subjects living in urban and rural areas of Nellore district, Andhra Pradesh, India, between 20-60 years, apparently normal as judged by the clinician basing on clinical and laboratory findings, were studied. Carotid-Femoral Pulse Wave Velocity (cf-PWV) a marker of arterial stiffness was assessed using non-invasive blood pressure curve monitoring (periscope). Furthermore, we also estimated serum levels of Copper (Cu), Zinc (Zn), Selenium (Se), chromium (Cr), Aluminium (Al), silicon (Si), Manganese (Mn), Molybdenum (Mb), Vanadium (Vn) and lead (Pb) using atomic absorption spectrophotometer. ANOVA and Chi-Square test were used to study the clinical correlations between severity of arterial stiffness, risk factors and trace elements. Results A total of 737 apparently healthy subjects participated in this cross-sectional study. Of the total 542 (73.5%) were from rural and the remaining 195 (26.5%) were living in urban areas, 328 (44.5%) were males, and 409 (55.5%) were females. A 63.5% (468/737) had normal arterial stiffness followed by 14.5% (107/737) with mild stiffness, 7% (57/737) had moderate stiffness and 14.2% (105/737) had severe arterial stiffness. Smoking, alcohol, blood pressures, fasting blood sugar, and total cholesterol, Cu, Al and Vn correlated (p<0.05) with different grades of arterial stiffness. Conclusion A 36.5% had

  19. POLVSM (Polarized Volume Scattering Meter) instrument: an innovative device to measure the directional and polarized scattering properties of hydrosols.

    PubMed

    Chami, Malik; Thirouard, Alexandre; Harmel, Tristan

    2014-10-20

    An innovative instrument dedicated to the multispectral measurements of the directional and polarized scattering properties of the hydrosols, so-called POLVSM, is described. The instrument could be used onboard a ship, as a benchtop instrument, or at laboratory. The originality of the POLVSM concept relies on the use of a double periscopic optical system whose role is (i) to separate the plane containing the light source from the scattering plane containing the sample and the receiver and (ii) to prevent from any specularly reflected light within the sample chamber. As a result, a wide range of scattering angle, namely from 1° to 179°, is covered by the detector. Another originality of the instrument is to measure the Mueller scattering matrix elements, including the degree of polarization. A relevant calibration procedure, which could be of great interest as well for other instruments, is proposed to convert the raw data into physical units. The relative uncertainty in POLVSM data was determined at ± 4.3%. The analysis of measurements of the volume scattering function and degree of polarization performed under controlled conditions for samples dominated either by inorganic hydrosols or phytoplankton monospecific species showed a good consistency with literature, thus confirming the good performance of the POLVSM device. Comparisons of POLVSM data with theoretical calculations showed that Mie theory could reproduce efficiently the measurements of the VSF and degree of polarization for the case of inorganic hydrosols sample, despite the likely non sphericity of these particles as revealed by one of the element of the Mueller matrix. Our results suggested as well that a sophisticated modeling of the heterogeneous internal structure of living cells, or at least, the use of layered sphere models, is needed to correctly predict the directional and polarized effects of phytoplankton on the oceanic radiation. The relevance of performing angularly resolved measurements

  20. Measuring parameters of large-aperture crystals used for generating optical harmonics

    SciTech Connect

    English, R. E.; Hibbard, R. L.; Michie, R. B.; Wegner, P. J.; Auerbach, J. M.; Norton, M. A.; Summers, M. D.; Perfect, S. A.

    1999-02-23

    it in place. We performed detailed finite-element modeling to predict the resulting shape of the mounted crystal. The prediction agreed with measurements of mounted crystals. We computed the physics of the frequency-conversion process to better quantify the effects on efficiency of variation in the crystal' s axis, changes in the shape of the crystal, and mounting-induced stress. We were able to accurately predict the frequency-conversion performance of 37-cm square crystals on Beamlet, a one-beam scientific prototype of the NIF laser architecture, using interferometric measurements of the mounted crystals and the model. In a 2{omega} measurement campaign, the model predicted 64.9% conversion efficiency; 64.1% was observed. When detuned by 640 µrad, the model and measurement agreement is even better (both were 10.4%). Finally, we completed the design and initial testing of a new optical metrology tool to measure the spatial variation of frequency conversion. This system employs a high-power subaperture beam from a commercial laser oscillator and rod amplifier. The beam interrogates the crystal' s aperture by moving the crystal horizontally on a translation stage and translating the laser beam vertically on an optical periscope. Precision alignment is maintained by means of a full-aperture reference mirror, a precision-machined surface on the crystal mount, and autocollimators (the goal for angular errors is 10 µrad). The autocollimators track the mounting angle of the crystal and the direction of the laser beam with respect to the reference mirror. The conversion efficiency can be directly measured by recording l{omega}, 2{omega}, 3{omega} energy levels during the scan and by rocking (i.e., tilting) the crystal mount over an angular range.

  1. Obituary: Cornell H. Mayer, 1921-2005

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, Venkataraman

    2006-12-01

    Cornell (Connie) H. Mayer, a pioneer of radio astronomy, died on 19 November 2005 of congestive heart failure at his home in Mt. Vernon, Virginia. He was eighty-three. Cornell Mayer was born in Ossian, Iowa on 10 December 1921. After graduating from the University of Iowa in 1943, he joined the Navy during World War II and was stationed at the Naval Research Laboratory (NRL) in Washington, DC. There he assisted Fred T. Haddock in the development of the first radar antenna inside a submarine periscope. This device has been credited with shortening the war in the Pacific because of the number of Japanese ships that were sunk with its aid. With Haddock, Connie also discovered centimeter-wave radio bursts from the sun coincident with solar flares. They made the first detection of thermal radio emission from the Orion nebula and other galactic HII regions. They also detected extragalactic objects and thus initiated the important field of centimeter-wave astronomy. Their observations were made with a 50-foot parabolic reflector on a gun mount located on the roof of one of the NRL buildings. This telescope had the world's highest radio resolving power for many years. With Haddock's departure to the University of Michigan in 1956 to create a new radio observatory there, Connie became head of a group in the Radio Astronomy Branch at NRL, where he remained until his retirement in 1980. Much of his work involved the measurement of planetary temperatures by analysis of radio emissions. By making technical innovations in instrumentation--such as replacing disc choppers with a ferrite switch to compare the sky and reference load, or using argon gas tubes for calibration--Connie greatly improved the performance of his equipment. This resulted in the discovery of an astonishing, 600oC surface temperature of Venus, which contradicted the widespread notion that Venus was similar to the Earth and potentially habitable. In spite of the extraordinarily careful and systematic way that

  2. Obituary: Cornell H. Mayer, 1921-2005

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, Venkataraman

    2006-12-01

    Cornell (Connie) H. Mayer, a pioneer of radio astronomy, died on 19 November 2005 of congestive heart failure at his home in Mt. Vernon, Virginia. He was eighty-three. Cornell Mayer was born in Ossian, Iowa on 10 December 1921. After graduating from the University of Iowa in 1943, he joined the Navy during World War II and was stationed at the Naval Research Laboratory (NRL) in Washington, DC. There he assisted Fred T. Haddock in the development of the first radar antenna inside a submarine periscope. This device has been credited with shortening the war in the Pacific because of the number of Japanese ships that were sunk with its aid. With Haddock, Connie also discovered centimeter-wave radio bursts from the sun coincident with solar flares. They made the first detection of thermal radio emission from the Orion nebula and other galactic HII regions. They also detected extragalactic objects and thus initiated the important field of centimeter-wave astronomy. Their observations were made with a 50-foot parabolic reflector on a gun mount located on the roof of one of the NRL buildings. This telescope had the world's highest radio resolving power for many years. With Haddock's departure to the University of Michigan in 1956 to create a new radio observatory there, Connie became head of a group in the Radio Astronomy Branch at NRL, where he remained until his retirement in 1980. Much of his work involved the measurement of planetary temperatures by analysis of radio emissions. By making technical innovations in instrumentation--such as replacing disc choppers with a ferrite switch to compare the sky and reference load, or using argon gas tubes for calibration--Connie greatly improved the performance of his equipment. This resulted in the discovery of an astonishing, 600oC surface temperature of Venus, which contradicted the widespread notion that Venus was similar to the Earth and potentially habitable. In spite of the extraordinarily careful and systematic way that

  3. Obituary: James Gilbert Baker, 1914-2005

    NASA Astrophysics Data System (ADS)

    Baker, Neal Kenton

    2005-12-01

    Harvard from 1946 to 1949. In 1948 he received the Presidential Medal for Merit for his work during World War II in the Office of Scientific Research and Development. In 1948, he moved to Orinda, California from Cambridge, Massachusetts and became a research associate of Lick Observatory for two years. He returned to Harvard in 1950. He had spent thousands of hours doing ray trace calculations on a Marchant calculator to produce his first aerial cameras. To replace the tedious calculations by hand, Dr. Baker introduced the use of numerical computers into the field of optics. His ray-trace program was one of the first applications run on the Harvard Mark II (1947) computer. Later on, he developed his own methodology to optimize the performance of his optical designs. These optical design computer programs were a family affair, developed under his direction by his own children to support his highly sophisticated designs of the 1960s and 1970s. For most of his career, Dr. Baker was involved with large system concepts covering not only the camera, but the camera delivery systems as well. As the chairman of U.S. Air Force Scientific Advisory Board, he recognized that national security requirements would require optical designs of even greater resolving power using aircraft at extreme altitudes. The need for such a plane resulted in the creation of the U-2 system consisting of a plane and camera functioning as a unit to create panoramic high-resolution aerial photographs. He formed Spica Incorporated in 1955 to perform the necessary optical design work for the US Government. The final design was a 36-inch f/10 system. Dr. Baker also designed the aircraft's periscope to allow the pilot to see his flight path. By 1958, he was almost solely responsible for all the cameras used in photoreconnaissance aircraft. He continued to serve on the President's Foreign Intelligence Advisory Board and on the Land Panel. Before the launch of Sputnik, he designed the Baker-Nunn satellite