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1

Periscopic Spine Surgery.  

National Technical Information Service (NTIS)

The Periscopic Spine Surgery project was envisioned to lay the ground work for developing the physician assist systems of the future. These systems will incorporate robotics, tracking, and visualization to improve the precision of instrument placement and...

K. R. Cleary

2007-01-01

2

Periscopic Spine Surgery.  

National Technical Information Service (NTIS)

The Periscopic Spine Surgery project was envisioned to lay the ground work for developing the physician assist systems of the future. These systems will incorporate robotics, tracking, and visualization to improve the precision of instrument placement and...

K. R. Cleary

2008-01-01

3

Steerable zoom periscope  

NASA Astrophysics Data System (ADS)

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.

Lidwell, Michael O.

1995-10-01

4

Submarine Periscope Eyeguard Housing Assembly.  

National Technical Information Service (NTIS)

A submarine periscope eyeguard housing assembly includes a viewing lens housing having a viewing lens aperture and viewing lens therein, first and second arm members fixed to the viewing lens housing and extending therefrom, a first blinder mounted on the...

W. C. Maciejewski R. Sayegh

2001-01-01

5

Eyecup Assembly for a Submarine Periscope.  

National Technical Information Service (NTIS)

An eyecup assembly for a submarine periscope blinder assembly includes an annularly-shaped ring having a multiplicity of holes, which are unthreaded, extending therethrough and adapted to receive screws for securing the eyecup assembly to a like multiplic...

W. C. Macieiewski R. Sayegh

2000-01-01

6

DESIGN OF PERISCOPES AND REMOTE VIEWING EQUIPMENT  

Microsoft Academic Search

A non-technical survey of the design features and limitations of ; industrial periscopes, including stereoscopic, with emphasis on remote control is ; presented. Also included are photographic instruments, effects of radiation on ; optical materials, television applications, and other types of viewing equipment. ; (P.C.H.);

Holeman

1957-01-01

7

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

8

PERISCOPE POP-IN BEAM MONITOR.  

SciTech Connect

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.

JOHNSON,E.D.

1998-05-07

9

Periscope pop-in beam monitor  

SciTech Connect

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.

Johnson, E.D.; Graves, W.S. [Brookhaven National Lab., Upton, NY (United States). National Synchrotron Light Source; Robinson, K.E. [STI Optronics, Bellevue, WA (United States)

1998-06-01

10

4. DETAIL SHOWING PERISCOPE AND SHIELDED WINDOWS ON EAST SIDE, ...  

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

4. DETAIL SHOWING PERISCOPE AND SHIELDED WINDOWS ON EAST SIDE, NORTH PART. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

11

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

12

Resolving Spectral Lines with a Periscope-Type DVD Spectroscope  

ERIC Educational Resources Information Center

|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…

Wakabayashi, Fumitaka

2008-01-01

13

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

14

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

15

OBLIQUE OF PIER S15/S16 WITH THE 1953 PERISCOPE STORAGE BUILDING ...  

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

OBLIQUE OF PIER S15/S16 WITH THE 1953 PERISCOPE STORAGE BUILDING AT THE END OF THE PIER. VIEW FACING NORTH-NORTHWEST. - U.S. Naval Base, Pearl Harbor, Waterfront Facilities, Various locations throughout base, Pearl City, Honolulu County, HI

16

A rotatable parallel glass plate periscope for effective aperture magnification in metrology  

Microsoft Academic Search

Optical instruments like autocollimator or interferometers have a limited aperture. Here we describe a simple device that effectively enlarges the viewing aperture, based on parallel shifting of the beam in a tilted parallel glass plate. This periscopic action is done with two additional degrees of freedom: variable radial displacement adjusted by the plate tilt angle and azimuthal movement controlled by

Haim Lotem; Zvi Horvitz; Zeev Avnet; Shlomo Hillel; Mordechai Lando

1995-01-01

17

Design Study of a Visible/Infrared Periscope for Intense Radiation Applications using Reflective Optics  

SciTech Connect

In magnetically confined fusion devices employing deuterium-tritium (D-T) operation, refractive optical components exposed to neutron and gamma radiation can be subject to degradation of the transmission characteristics, induced luminescence, and altered mechanical properties including dimensional changes. Although radiation resistant refractive optics functioned well for the Tokamak Fusion Test Reactor (TFTR) periscope system during D-T operation, this design approach is unpromising in the much more hostile radiation environment of future D-T devices such as the International Thermonumclear Experimental Reactor (ITER). Under contract to the Princeton Plasma Physics Laboratory, Ball Aerospace of Colorado carried out a periscope design study based on the use of reflective optics. In this design, beryllium reflective input optics supported by a fused silica optical bench were interfaced to a Cassegrain relay system to transfer plasma images to remotely located cameras. This system is also capable of measuring first-wall surface temperatures in the range of 300 - 2,000 degrees C even under projected heating of the reflective optics themselves to several hundred degrees Celsius. Tests of beryllium mirror samples, however, revealed that operation at temperatures above 700 degrees C leads to a loss of specular reflectivity, thus placing an upper limit on the acceptable thermal environment. The main results of this periscope study are presented in this paper.

Medley, S.S.

1998-05-01

18

Periscope graft to extend distal landing zone in ruptured thoracoabdominal aneurysms with short distal necks.  

PubMed

Endovascular aneurysm repair (EVAR) of ruptured thoracoabdominal aortic aneurysms may be compromised or even impossible due to short proximal and/or distal necks or landing zones, respectively. Supra-aortic branches may limit the proximal anchorage and visceral or renal arteries the distal anchorage of endografts. While solutions have been proposed to overcome the problem of a short proximal neck, no technique has been described that solves the problem of a short distal neck. We present the "periscope technique," which allows extension of the distal landing zone and complete endovascular treatment of ruptured thoracoabdominal aneurysms with short distal necks using devices already stocked in most centers performing EVAR procedures. PMID:20299176

Rancic, Zoran; Pfammatter, Thomas; Lachat, Mario; Hechelhammer, Lukas; Frauenfelder, Thomas; Veith, Frank J; Criado, Frank J; Mayer, Dieter

2010-03-29

19

Development of a periscopic confocal microscope for in situ observation under high magnetic fields  

NASA Astrophysics Data System (ADS)

This article contains a description of a periscope system developed for in situ high-resolution observation under high magnetic fields in combination with a confocal scanning laser microscope. It fits a typical cryocooler-operated superconducting magnet with a 100 mm diam room-temperature bore. To avoid the unwanted effect of magnetic fields, the laser scanning unit was positioned at sufficient distance from the field. The resolution obtained was several hundreds of nanometers. The observation area can be changed in situ by the xyz fine-motion stage. Processing of obtained images can be done in a manner nearly identical to that with a conventional confocal scanning laser microscope. Images of the in situ observation of electroless silver deposition under a 12 T field are presented.

Hirota, Noriyuki; Ode, Takahiro

2006-03-01

20

Research on data communication method in periscope semi-physical training simulation system  

NASA Astrophysics Data System (ADS)

Data communication plays a very important role in the hardware in the loop simulation system. The system architecture of periscope semi-physical simulation system is proposed at first. Then the data communication method based on FINS between PLC and PC is introduced, the user's interaction of scene is achieved by PLC. The communication based on TCP between 2D chart console and scene simulation system is also introduced. The 6-DOF motion model and the scene simulation system is connected by TCP, and a DR method is introduced in solving the data amount problem. The test shows that the simulation system has no error package and no missing in a simulation circle. And can meet the requirements of training, also shows good performance in reliability and real-time.

Xiao, Jianbo; Hu, Dabin

2013-03-01

21

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

PubMed

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. PMID:23636248

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

2013-05-01

22

XUV\\/FUV 'Periscope' for Radiative Divertor Studies of C and N on DIII-D and Alcator C-Mod  

Microsoft Academic Search

One of the recent developmental activities of the Plasma Spectroscopy Group at JHU involves designing and constructing novel 'periscope' type divertor diagnostics for the far ultraviolet (FUV), and the extreme ultraviolet and soft-x-ray (XUV) impurity emissions. In this development we address the problems associated with extracting local (i.e. not contaminated by main plasma emission) signals of resonant spectral line emissions

S. P. Regan; M. J. May; V. A. Soukhanovskii; M. Finkenthal; H. W. Moos

1996-01-01

23

How a submarine returns to periscope depth: Analysing complex socio-technical systems using Cognitive Work Analysis.  

PubMed

This paper presents the application of Cognitive Work Analysis to the description of the functions, situations, activities, decisions, strategies, and competencies of a Trafalgar class submarine when performing the function of returning to periscope depth. All five phases of Cognitive Work Analysis are presented, namely: Work Domain Analysis, Control Task Analysis, Strategies Analysis, Social Organisation and Cooperation Analysis, and Worker Competencies Analysis. Complex socio-technical systems are difficult to analyse but Cognitive Work Analysis offers an integrated way of analysing complex systems with the core of functional means-ends analysis underlying all of the other representations. The joined-up analysis offers a coherent framework for understanding how socio-technical systems work. Data were collected through observation and interviews at different sites across the UK. The resultant representations present a statement of how the work domain and current activities are configured in this complex socio-technical system. This is intended to provide a baseline, from which all future conceptions of the domain may be compared. The strength of the analysis is in the multiple representations from which the constraints acting on the work may be analysed. Future research needs to challenge the assumptions behind these constraints in order to develop new ways of working. PMID:23702259

Stanton, Neville A; Bessell, Kevin

2013-05-20

24

XUV/FUV 'Periscope' for Radiative Divertor Studies of C and N on DIII-D and Alcator C-Mod  

NASA Astrophysics Data System (ADS)

One of the recent developmental activities of the Plasma Spectroscopy Group at JHU involves designing and constructing novel 'periscope' type divertor diagnostics for the far ultraviolet (FUV), and the extreme ultraviolet and soft-x-ray (XUV) impurity emissions. In this development we address the problems associated with extracting local (i.e. not contaminated by main plasma emission) signals of resonant spectral line emissions from impurities in the divertor region, and present the design of the XUV/FUV 'Periscope'. The device planned for Alcator is designed around the resonant emissions of H I to B I-like N, while the DIII-D instrument is designed for the resonant emissions of carbon ions. This multispectral, multispatial device will utilize multilayer mirrors (MLMs), transmission gratings, reflection gratings, and perhaps MLM-coated gratings as dispersive elements; will have a broad spectral ranges extending from 20 to 2500 Åand will be located in close proximity to the plasma. The objectives of this device are to estimate the divertor impurity distribution, content, and power losses in conjunction with the divertor Thomson Scattering and Bolometric measurements. Supported by U.S. DOE Grant DE-FG02-86ER53214 at JHU.

Regan, S. P.; May, M. J.; Soukhanovskii, V. A.; Finkenthal, M.; Moos, H. W.

1996-11-01

25

Chimney and periscope grafts observed over 2 years after their use to revascularize 169 renovisceral branches in 77 patients with complex aortic aneurysms.  

PubMed

Purpose : To evaluate the performance of periscope and/or chimney grafts (CPGs) in the endovascular treatment of pararenal or thoracoabdominal aneurysms using off-the-shelf devices. Methods : Between February 2002 and August 2012, 77 consecutive patients (62 men; mean age 73±9 years) suffering from pararenal aortic (n=55), thoracoabdominal (n=16), or arch to visceral artery aneurysms (n=6) were treated with aortic stent-graft implantation requiring chimney and/or periscope grafts to maintain side branch perfusion. CPGs were planned in advance and were not used as bailout. A standardized follow-up protocol including computed tomographic angiography, laboratory testing, and clinical examination was performed at 6 weeks; 3, 6, and 12 months; and annually thereafter. Results : Technical success was achieved in 76 (99%) patients; 1 branch stent-graft became dislocated from a renal artery, which could not be re-accessed. Overall, 169 target vessels (121 renal arteries, 30 superior mesenteric arteries, 17 celiac trunks, and 1 inferior mesenteric artery) were addressed with the chimney graft configuration in 111 and the periscope graft configuration in 58. In total, 228 devices were used for the CPGs: 213 Viabahn stent-grafts and 15 bare metal stents. Over a mean 25±16 months (range 1-121), 9 patients died of unrelated causes. Nearly all (95%) of the patients demonstrated a decreased or stable aneurysm size on imaging; there was a mean 13% shrinkage in aneurysm diameter. Twenty patients had primary type I/III endoleaks at discharge; in follow-up, only 3 of these were still present (no secondary or recurrent endoleaks were noted). Additional endovascular maneuvers were required for CPG-related complications in 13 patients from intervention throughout follow-up. Overall, 4 CPGs occluded (98% target vessel patency); no stent-graft migration was observed. Renal function remained stable in all patients. Conclusion : In this series, the use of CPGs has proven to be a feasible, safe, and effective way to treat thoracoabdominal and pararenal aneurysms with maintenance of blood flow to the renovisceral arteries. Nearly all of the aneurysms showed no increase in diameter over a >2-year mean follow-up, which supports the midterm adequacy of the CPG technique as a method to effectively revascularize branch vessels with few endoleaks or branch occlusions. PMID:24093310

Lachat, Mario; Veith, Frank J; Pfammatter, Thomas; Glenck, Michael; Bettex, Dominique; Mayer, Dieter; Rancic, Zoran; Gloekler, Steffen; Pecoraro, Felice

2013-10-01

26

Periscopic Spine Surgery.  

National Technical Information Service (NTIS)

This project is aimed at improving the state of the art of image- guided and minimally invasive procedures by developing a new generation of clinical techniques along with the computer-based hardware and software needed for their implementation. The focus...

K. R. Cleary

2005-01-01

27

Periscopic Spine Surgery.  

National Technical Information Service (NTIS)

This project is aimed at improving the state of the art of image-guided and minimally invasive spine procedures by developing a new generation of clinical techniques along with the computer-based hardware and software needed for their implementation. The ...

K. Cleary

2000-01-01

28

Periscopic Spine Surgery.  

National Technical Information Service (NTIS)

The modern operating room requires an increasing number of new surgical instruments, monitoring and imaging devices, information systems, and communication networks. While these individual technologies are improving, attention must also be paid to integra...

K. R. Cleary

2005-01-01

29

Periscopic media tour  

Microsoft Academic Search

Purpose – Over a two-month period, the editor of this media review has searched worldwide for the most interesting and useful articles, blogs and books on the topic of strategic management. Design\\/methodology\\/approach – In addition to his own finds, the editor sorted through suggestions by a team of veteran top managers and senior academics. Findings – The result is a

Craig Henry

2007-01-01

30

Command and Control Workstation of the Future; Subsurface and Periscope Views.  

National Technical Information Service (NTIS)

Today's tactical commander needs to assimilate enormous amounts of information to make reasonable decisions. Graphics displays can be a valuable tool in conveying such information in a clear and concise manner. Our vehicle for studying such displays is a ...

C. E. Phillips G. K. Weeks

1989-01-01

31

Periscope Design and Testing for Remote Viewing Inside DIII-D  

Microsoft Academic Search

Spectroscopy and imaging are key diagnostics for studying transport and edge physics in tokamaks. However, high neutron flux in environments such as ITER will degrade the performance of optical diagnostics. Optical fibers are particularly susceptible to neutron damage because of their extended length. For example, in existing tokamaks optical fiber damage has been observed for neutron fluences of order 10^16

J. H. Yu; E. M. Hollmann; L. Chousal

2006-01-01

32

Lens Assembly and Housing Therefor for Use with a Submarine Periscope.  

National Technical Information Service (NTIS)

In a lens assembly and housing therefor for use in conjunction with an optical apparatus, the lens assembly includes a lens frame of nonferrous material and defining a window having a lip therein along a periphery of the window, a lens disposed in the win...

W. C. Maciejewski R. Sayegh

2001-01-01

33

Drift sight replacement in the U-2  

Microsoft Academic Search

When first deployed in the mid 1950s, the U-2 had an inverted periscope (Drift Sight) to provide the pilot a view of the area below the aircraft. During a recent glass cockpit upgrade, this periscope was removed. This paper discusses: \\

Lawrence J. Bialecki

2005-01-01

34

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

35

Assessment of Shallow Water Near Surface Response of Submersible Vehicles.  

National Technical Information Service (NTIS)

Vertical plane response of submersible vehicles in the proximity of a free surface in both deep and shallow waters is evaluated using a potential flow, strip theory solver. Three criteria, namely periscope submergence, sail broaching, and collision are us...

U. Toprak

1996-01-01

36

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

37

3. VIEW OF ESCAPE TUNNEL IN NORTH FACE OF LAUNCH ...  

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

3. VIEW OF ESCAPE TUNNEL IN NORTH FACE OF LAUNCH OPERATIONS BUILDING. BUNKER PERISCOPE VISIBLE ABOVE RIGHT CORNER OF TUNNEL. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

38

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

PubMed

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

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

39

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

NASA Astrophysics Data System (ADS)

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 4×10-5 were obtained with a 25% bandwidth, and 2×10-5>/SUP> with a 20% bandwidth, at a central wavelength of 9.5 ?m. The best short term nulls at 20% bandwidth were approximately 9×10-6, in line with error budget predictions and the limits of the current generation of hardware.

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.

2009-02-01

40

Optical system design for infrared imaging system of Korea Superconducting Tokamak Advanced Research (KSTAR) device  

NASA Astrophysics Data System (ADS)

The first infrared imaging system, for monitoring the temperature of the inner wall and localized hot spot such as the ICRH antenna was installed on the midplane of the D-port in the Korea Superconducting Tokamak Advanced Research (KSTAR). The cassette system of KSTAR makes a periscope inevitable for infrared imaging system. The periscope is composed of a 3 functional optical lens set (input beam shaper, beam deliverer, output beam shaper). CaF2 was chosen for the material of the lens elements. As an infrared image camera, FLIR/ThermoVision SC6000HS is used. The infrared camera has 640 × 512 pixel resolution and a camera lens set with 25.4 mm of focus length and 50 mm of input pupil. The periscope was designed to have 2.7 m of overall length, 19.07 mm of focal length and 3.81 of f-number.

Oh, S.; Seo, D.; KSTAR Team

2012-02-01

41

Overview metal mirrors' prospects in fusion reactors  

Microsoft Academic Search

A large part of high-temperature plasma diagnostics has to do with plasma electromagnetic radiation in various spectral ranges. The need to find out the spatial profiles of many plasma parameters makes it necessary to have special overview mirrors very close to the confined plasma boundaries. These mirrors should send the plasma radiation to periscopic channels having radiation analyzers and detectors

V. S. Voitsenya; V. V. Gann; V. T. Gritsyna; V. G. Konovalov; D. V. Orlinskii; O. S. Pavlichenko; A. N. Shapoval

1994-01-01

42

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

43

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

44

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

45

Effectiveness of the Training and Development Programme in improving the HRD: A CPCL Experience  

Microsoft Academic Search

Training is the periscope to see the future. It is intended to identify the future of the organization to develop and steer them to where they belong. Development creates generalists and helps people to think strategically, even when their present jobs do not call for such thinking. It pushes and stretches people beyond their present function. Hence this paper attempts

Velmurugan P. S; Senthamil Raja A; Palanichamy P

2009-01-01

46

Infrared Thermography on TFR 600 Tokamak.  

National Technical Information Service (NTIS)

Infrared thermography with a single InSb detector and with a scanning camera has been performed on the TFR fusion device. High power neutral beam injection diagnostic by means of an infrared periscope is showed to be possible. Surface temperature measurem...

R. Romain

1980-01-01

47

3. EAST SIDE FROM ATOP TUNNEL, SHOWING BLAST SHIELDED WINDOWS ...  

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

3. EAST SIDE FROM ATOP TUNNEL, SHOWING BLAST SHIELDED WINDOWS AND PERISCOPE FACING TO TEST STAND 1-3. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

48

Photocopy of drawing located at National Archives, San Bruno, California ...  

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

Photocopy of drawing located at National Archives, San Bruno, California (Navy # 680-A-2). Part of ground floor, optical shop and roof periscope testing tower; 1936. - Mare Island Naval Shipyard, Machine Shop, California Avenue, southwest corner of California Avenue & Thirteenth Street, Vallejo, Solano County, CA

49

4. VIEW OF CABLE SHED AND CABLE TRAY EMANATING FROM ...  

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

4. VIEW OF CABLE SHED AND CABLE TRAY EMANATING FROM NORTH FACE OF LAUNCH OPERATIONS BUILDING. TOPS OF BUNKER PERISCOPE AND FLAGPOLE ON ROOF OF LAUNCH OPERATIONS BUILDING IN BACKGROUND - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

50

Innovative optronics for the new PUMA tank  

NASA Astrophysics Data System (ADS)

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.

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

2010-04-01

51

Drift sight replacement in the U-2  

NASA Astrophysics Data System (ADS)

When first deployed in the mid 1950s, the U-2 had an inverted periscope (Drift Sight) to provide the pilot a view of the area below the aircraft. During a recent glass cockpit upgrade, this periscope was removed. This paper discusses: " The development activity leading up to flight test of an Electro Optical Viewsight System (EOVS) replacement for the Drift Sight. The impact and design consideration of using an inexpensive Commercial Off the Shelf (COTS) cameral module, originally designed for small hand held video cameras, " The process used to develop the basic requirements and how early input from the user community lead to an effective design (e.g.., Hand Grip), " The ruggedization techniques necessary to ensure the camera would meet the vibration, thermal, and Electro Magnetic Interface (EMI) environment, " Actual system performance data, " Growth "hooks" and how they were accommodated in a firm fixed price contract.

Bialecki, Lawrence J.

2005-05-01

52

Streambank plants vital to water quality  

SciTech Connect

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.

Sherman, H.

1989-08-01

53

Development of a CRUD'' particle size distribution and its effect on cask source term and containment analyses  

Microsoft Academic Search

Spent pressurized-water reactor (PWR) and boiling-water reactor (BWR) fuel rods from three reactors were examined by hot cell periscope, energy dispersive x-ray analysis, and scanning electron micrography. In the case of fuel from the Quad Cities reactor, it was possible to develop a complete particle size distribution. It was found to be log-normal, with a median geometric diameter of 3

C. K. Thornhill; H. Jordan; T. Sanders; W. H. Lake

1989-01-01

54

Beyond obedience: Jesus and the law in Matthew 5:17-20  

Microsoft Academic Search

The following study is centered on four verses in Matthew’s Gospel, 5:17-20. With respect to these verses, our thesis is: in Matthew 5:17-20 Jesus addresses the tension that arises from the juxtaposition of the authority of the scribes and Pharisees with his own authority: continuity\\/discontinuation, mere obedience\\/surpassing excess are the polarities of this tension. In this periscope Jesus is presented

Charles Thomas Brown

1991-01-01

55

C-III flow measurements with a coherence imaging spectrometer.  

PubMed

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. PMID:23126924

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

2012-10-01

56

Infrared thermography on TFR 600 Tokamak  

NASA Astrophysics Data System (ADS)

Infrared thermography with a single InSb detector and with a scanning camera was performed on the TFR fusion device. High power neutral beam injection diagnostics by means of an infrared periscope, was shown to be possible. Surface temperature measurements on the limiter during the discharge were made in order to evaluate the power deposited by the plasma on part of the inner wall. Various attempts of infrared detection on the high power neutral injector prototype vessel are described, particularly the measurement of the power deposited on one of the extraction grids of the ion source.

Romain, R.

1980-06-01

57

Design considerations, tooling, and equipment for remote in-service inspection of radioactive piping and pressure-vessel systems  

SciTech Connect

This paper summarizes results obtained in use of remotely-operated nondestructive testing (NDT) equipment for inspection of reactor-system components. Experience obtained in operating the Fast Flux Test Facility (FFTF) has provided a basis for field verification of remote NDT equipment designs and has suggested development improvements. Remote Viewing and data gathering systems used include periscopes, borescopes, fiberscopes, hybrid borescopes/fiberscopes, and closed circuit television. A summary of design consideration for inspection equipment and power plant design is presented to achieve improved equipment operation and reduction of plant maintenance downtime.

Swannack, D.L.; Schmoker, D.S.

1983-01-01

58

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

NASA Astrophysics Data System (ADS)

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.

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

2004-05-01

59

Improved charge exchange spectroscopy on the Joint European Torus for ion temperature and rotation velocity profiles  

SciTech Connect

The Joint European Torus (JET) edge charge exchange recombination spectroscopy diagnostic has recently been enhanced to extend its spatial coverage and improve its time resolution. Two identical periscopes have been installed on opposite ports so that they have perfectly symmetrical views of the edge plasma. This matched viewing geometry allows both the poloidal and toroidal components of the impurity ion rotation velocity to be accurately resolved. These measurements play a crucial role in the understanding of the physics of edge phenomena such as edge transport barrier formation and enhanced light microscopes. The diagnostic also has a more central view of the plasma with a third periscope that faces up towards the top of the vessel. This is a new configuration for the diagnostic and allows the poloidal rotation velocity profile to be measured further in towards the plasma core than previously possible. The new upward facing, core plasma viewing arrangement provides the advantage that the spatial evolution of the internal transport barrier can be tracked from its formation. An additional spectrometer-detector system doubles the total number of charge exchange recombination spectroscopy lines of sight that are analyzed and improves time resolution from 50 to 10 ms.

Andrew, Yasmin; Hawkes, N. C.; Crombe, K. [Euratom/UKAEA Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Department of Applied Physics, Ghent University, Rozier 44, B-9000, Ghent (Belgium)

2006-10-15

60

Atmospheric monitoring by lidar in an industrial area of Southern Italy  

NASA Astrophysics Data System (ADS)

A lidar system able to measure simultaneously different atmospheric parameters in the lower troposphere have been developed and used to monitor the air quality of an industrial area of Southern Italy. The system is based on a Nd:YAG laser pumping two dye lasers, and on two Newtonian telescopes, equipped with periscopes for 3D mapping. One telescope is devoted to DIAL and the other to the N2 and H2O Raman channels, and to the elastic channels at 1064 nm, 532 nm and 355 nm. Aerosol backscattering coefficients measurements have evidenced the presence of an aerosol layer. The laser has been characterized by measuring its temporal evolution and by correlating it with atmospheric transmissivity profiles measured at different zenithal angles. Preliminary results of atmospheric pollutants concentration measurements by UV DIAL technique are also reported.

Amodeo, Aldo; Ambrico, Paolo F.; Amoruso, Salvatore; Boselli, Antonella; Pandolfi, M.; Pappalardo, Gelsomina; Spinelli, Nicola; Velotta, Raffaele

2000-02-01

61

Review of OCA activities on nulling testbench PERSEE  

NASA Astrophysics Data System (ADS)

We present a review of our activities on PERSEE (Pégase Experiment for Research and Stabilization of Extreme Extinction) at Observatoire de la Côte d'Azur (OCA). PERSEE is a laboratory testbench aiming at achieving a stabilized nulling ratio better than 10-4 in the astronomical bands K and M, in presence of flight-representative spacecraft perturbations. The bench has been jointly developed by a Consortium of six French institutes and companies, among which OCA was responsible for the star simulator and of the opto-mechanical studies, procurement and manufacturing of the optical train. In this communication are presented the alignment and image quality requirements and the optomechanical design of the illumination module and main optical train, including a periscope Achromatic Phase Shifter (APS), tip-tilt mirrors used to introduce and then compensate for dynamic disturbances, delay lines, beam compressors and fiber injection optics. Preliminary test results of the star simulator are also provided.

Hénault, François; Girard, Paul; Marcotto, Aurélie; Mauclert, Nicolas; Bailet, Christophe; Clausse, Jean-Michel; Mourard, Denis; Rabbia, Yves; Roussel, Alain; Barillot, Marc; Cassaing, Frédéric; Le Duigou, Jean-Michel

2010-07-01

62

Impurity Flow Measurements in DIII-D using Coherence Imaging Spectroscopy  

NASA Astrophysics Data System (ADS)

Imaging interferometers have been used to measure the 2-D distribution of the Doppler shift of impurity emission in both the lower and upper DIII-D divertors. The interferometer design has been simplified to a single birefringent plate between two polarizers, and improved calibration techniques have been implemented, including temperature stabilization. Measurements of other impurity species such as CII have been added. An image-intensified camera in the upper divertor has enabled measurement of the flows in the crown of the plasma during lower single-null divertor operation. In general, flows are in opposite directions on the inner and outer scrape-off layers in the divertor, as expected from the magnetic geometry. Initial results from a wide view periscope of the whole plasma cross section will also be presented.

Allen, S. L.; Meier, E. T.; Weber, T. R.; Hill, D. N.; Meyer, W. H.; Porter, G. D.; Howard, J.

2012-10-01

63

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

NASA Astrophysics Data System (ADS)

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.

Yoder, Paul R., Jr.

1986-01-01

64

Examination of the first irradiated LOFT fuel module  

SciTech Connect

The first Loss-of-Fluid Test (LOFT) center fuel module was nondestructively examined in order to assess any changes after power range testing and three large-break loss-of-coolant experiments (LOCEs). The examination consisted of evaluation of LOCE measurement data; measurement of withdrawal forces during removal of the module from the reactor; poolside examination of the exposed fuel module surfaces, using an underwater periscope, 35-mm camera, and closed circuit television; and poolside measurements of the rod-to-rod spacing, using a Sulo probe. The performance of the equipment is assessed from the results of the examination. Color standards are required for underwater color photography, and fuel rod deflection must be considered in evaluting rod-to-rod spaces.

Cook, J.A.; Olsen, C.S.

1981-01-01

65

Overview of Engine Combustion Research at Sandia National Laboratories  

SciTech Connect

The objectives of this paper are to describe the ongoing projects in diesel engine combustion research at Sandia National Laboratories' Combustion Research Facility and to detail recent experimental results. The approach we are employing is to assemble experimental hardware that mimic realistic engine geometries while enabling optical access. For example, we are using multi-cylinder engine heads or one-cylinder versions of production heads mated to one-cylinder engine blocks. Optical access is then obtained through a periscope in an exhaust valve, quartz windows in the piston crown, windows in spacer plates just below the head, or quartz cylinder liners. We have three diesel engine experiments supported by the Department of Energy, Office of Heavy Vehicle Technologies: a one-cylinder version of a Cummins heavy-duty engine, a diesel simulation facility, and a one-cylinder Caterpillar engine to evaluate combustion of alternative diesel fuels.

Robert W. Carling; Gurpreet Singh

1999-04-26

66

Aspects of high-temperature pyrometry for measurements in ultrahigh vacuum  

SciTech Connect

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.

Neuhaus, P.; Egry, I.; Lohoefer, G. (German Aerospace Research Establishment, Koeln (Germany))

1992-01-01

67

Overview metal mirrors` prospects in fusion reactors  

SciTech Connect

A large part of high-temperature plasma diagnostics has to do with plasma electromagnetic radiation in various spectral ranges. The need to find out the spatial profiles of many plasma parameters makes it necessary to have special overview mirrors very close to the confined plasma boundaries. These mirrors should send the plasma radiation to periscopic channels having radiation analyzers and detectors at the output. Due to their closeness to a nuclear fusion condition plasma, the mirrors will be exposed to {gamma}-ray, X-ray, neutron, and charge-exchange atom fluxes only several times less intense than at the reactor first wall. Moreover, the mirror surface will suffer the action of a {approximately}10{sup 10} cm{sup {minus}3} density background plasma, consisting not only of hydrogen and helium ions but also of the fist wall materials` ones. We present below some estimates of mirror materials radiation resistance, regarding their ability to preserve an acceptable surface reflectivity notwithstanding the irradiation-caused deterioration. 15 refs., 3 figs., 1 tab.

Voitsenya, V.S.; Gann, V.V.; Konovalov, V.G.; Pavlichenko, O.S.; Shapoval, A.N. [Khar`kov Physics and Technology Institute (Ukraine); Gritsyna, V.T. [Khar`kov State Univ. (Ukraine); Orlinskii, D.V. [Kurchatov Institute Russian Research Centre, Moscow (Russian Federation)

1994-12-31

68

Target plane imager for inertial confinement fusion  

SciTech Connect

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.

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

1985-01-30

69

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

SciTech Connect

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.

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

1999-03-01

70

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

PubMed

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. PMID:21923292

Sansolios, Sanne; Mikkelsen, Bent Egberg

2011-10-01

71

Microtubules for nonlinear optical limiting  

NASA Astrophysics Data System (ADS)

The effort in visible laser eye and sensor protection has focussed on several problems, one of which was the threshold for laser eye damage of 1.0-0.1 microjoule (micro J)/sq cm (or 1000-100 W/sq cm for a nanosecond pulse) over a broad wavelength range form 400-700 nm. This value is the so-called 'clamping threshold' which is the maximum intensity permitted to exit the optical device, regardless of the input intensity. The most interest was concentrated in finding a solution for nanosecond threats by a retrofit of existing equipment (binoculars, periscope viewers, etc.,) or by fabrication into a simple set of goggles or a visor. This very low clamping threshold, or course, requires a very highly nonlinear material that is fast and operates over a wide frequency range. The nonlinear materials work can be classified into the following types: (1) liquid crystals; (2) organometallics and polymers; (3) ultrarapid crystallizing alloys and other thermally induced phase changes; and (4) phase conjugate mirrors.

Wellinghoff, Stephen T.; Baker, Charles K.; Sablik, Martin J.; Hill, Ralph H.; Naegeli, David W.

1993-12-01

72

History of remote operations and robotics in nuclear facilities  

SciTech Connect

The field of remote technology is continuing to evolve to support man's efforts to perform tasks in hostile environments. Remote technology has roots which reach into the early history of man. Fireplace pokers, blacksmith's tongs, and periscopes are examples of the beginnings of remote technology. The technology which we recognize today has evolved over the last 45-plus years to support human operations in hostile environments such as nuclear fission and fusion, space, underwater, hazardous chemical, and hazardous manufacturing. The four major categories of approach to remote technology have been (1) protective clothing and equipment for direct human entry, (2) extended reach tools using distance for safety, (3) telemanipulators with barriers for safety, and (4) teleoperators incorporating mobility with distance and/or barriers for safety. The government and commercial nuclear industry has driven the development of the majority of the actual teleoperator hardware available today. This hardware has been developed due to the unsatisfactory performance of the protective-clothing approach in many hostile applications. Systems which have been developed include crane/impact wrench systems, unilateral power manipulators, mechanical master/slaves, and servomanipulators. Work for space applications has been primarily research oriented with few successful space applications, although the shuttle's remote manipulator system has been successful. In the last decade, underwater applications have moved forward significantly, with the offshore oil industry and military applications providing the primary impetus. This document consists of viewgraphs and subtitled figures.

Herndon, J.N.

1992-01-01

73

The new infrared imaging system on Alcator C-Mod  

NASA Astrophysics Data System (ADS)

A new infrared imaging system has been installed on Alcator C-Mod. This system uses an Amber Radiance 1 IR video camera (filtered to the 4.2-4.4 ?m band) to view a 30 cm×30 cm region of the lower divertor from above by means of a re-entrant 5-m long ZnSe based periscope. Capture of the standard 30 Hz video frames (8-bit) and camera control are performed remotely over fiber optic links by a Windows 95 PC, using a MuTech MV-1000 video grabber board. Plans are under way to directly capture the 60 Hz, 12-bit, 256×256 pixel images using a digital video camera interface with a fiber optic link from EDT (Beaverton, Oregon). Preliminary results show that during nondisruptive discharges no substantial surface temperature increase is observed on the upper sections of the divertor, with the exception of ``hot spots,'' although occasionally, increased heating in toroidal bands is seen. Bands can also be observed after disruptions that result in a downward movement of the plasma.

Maqueda, R. J.; Wurden, G. A.; Terry, J. L.; Stillerman, J. A.

1999-01-01

74

Fast Visible and IR Imaging in Alcator C-Mod  

NASA Astrophysics Data System (ADS)

Two imaging systems have been installed on C-Mod as part of the LANL/MIT collaboration. The first one is a fast Kodak digital camera system that can store 1600 full frames at rates up to 1000 frames/sec and with gating times from a few microseconds to 1 millisecond. The second system uses an Amber Radiance IR camera (3-5 ?m band and 30 frames/sec) and should be able to measure heat loads on the divertor surfaces. A re-entrant periscope viewing the lower, closed divertor (30 cm x 30 cm region) from above and based on ZnSe optics is used to transport the image to the IR camera located 5 m away. The data acquisiton and camera control of the IR system is perfomed remotely through fiber optic links by a PC running Windows 95 and using a MuTech MV-1000 video grabber board. Results obtained during the 1997 campaign will be presented. These might include: edge turbulence, fast-scanning probe injection of impurities, radiation from runaway electrons, heat loads during attached/detached plasma operation and disruptions; as well as localization of hot spots, possible sources of molybdenum.

Maqueda, R. J.; Wurden, G. A.; Terry, J. L.; Stillerman, J. A.; Zweben, S. J.

1997-11-01

75

Statis omnidirectional stereoscopic display system  

NASA Astrophysics Data System (ADS)

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.

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

1999-11-01

76

Beryllium Use in the Advanced Test Reactor  

SciTech Connect

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.

Glen R. Longhurst

2007-12-01

77

Opto-mechanical devices for the Antares automatic beam alignment system  

SciTech Connect

Antares is a 24-beam CO/sub 2/ laser system for controlled fusion research, under construction at Los Alamos National Laboratory. Rapid automatic alignment of this system is required prior to each experimental shot. Unique opto-mechanical alignment devices, which have been developed specifically for this automatic alignment system, are discussed. A variable focus alignment telescope views point light sources. A beam expander/spatial filter processes both a visible Krypton Ion and a 10.6 ..mu..m CO/sub 2/ alignment laser. The periscope/carousel device provides the means by which the alignment telescope can sequentially view each of twelve optical trains in each power amplifier. The polyhedron alignment device projects a point-light source for both centering and pointing alignment at the polyhedron mirror. The rotating wedge alignment device provides a sequencing point-light source and also compensates for dispersion between visible and 10.6 ..mu..m radiation. The back reflector flip in remotely positions point-light sources at the back reflector mirrors. A light source box illuminates optic fibers with high intensity white light which is distributed to the various point-light sources in the system.

Swann, T.; Combs, C.; Witt, J.

1981-01-01

78

Multispectral lidar system: design, build, and test  

NASA Astrophysics Data System (ADS)

Long range, combined UV-IR LIDAR system was built and tested. The system was developed to operate as a multi-wavelength DIAL in the IR (8-11 ?m), dual exciting wavelengths LIF LIDAR in the UV, and aerosol map and track at 1.5 ?m. The IR transmitter is a continuous tunable solid-state Tandem Optical Parametric Oscillator (OPO) [1]. The first OPO stage generates the 1.5 ?m beam and the second OPO stage pumped by the first, generates the IR band. In the UV the transmitter generates and transmits either the 266 nm or the 355 nm wavelengths sequentially. All the outgoing laser beams are prealigned to ensure geometric overlap over the measured paths. Energy references are measured for each beam on every pulse. The receiver is based on a single reflective telescope with coatings optimized for both the UV and the IR. The optical signal is routed between the different detection packages by means of a computerized optical scanner mirror. The receiver-transmitter layout is based on periscope geometry and is equipped with a large ?-? scanner. Computer control enables fast switching between the different measurements and wavelengths, data acquisition and spatial scan as well. The system was built inside a mobile trailer and was field tested to descriminate aerosol types in a complex enviroment [2].

Fastig, S.; Ehrlich, Y.; Pearl, S.; Naor, E.; Kraus, Y.; Inbar, T.; Katz, D.

2010-04-01

79

Development of imaging bolometers for magnetic fusion reactors (invited)  

NASA Astrophysics Data System (ADS)

Imaging bolometers utilize an infrared (IR) video camera to measure the change in temperature of a thin foil exposed to the plasma radiation, thereby avoiding the risks of conventional resistive bolometers related to electric cabling and vacuum feedthroughs in a reactor environment. A prototype of the IR imaging video bolometer (IRVB) has been installed and operated on the JT-60U tokamak demonstrating its applicability to a reactor environment and its ability to provide two-dimensional measurements of the radiation emissivity in a poloidal cross section. In this paper we review this development and present the first results of an upgraded version of this IRVB on JT-60U. This upgrade utilizes a state-of-the-art IR camera (FLIR/Indigo Phoenix-InSb) (3-5 ?m, 256×360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF2 optics and an aluminum mirror. The IRVB foil is 7 cm×9 cm×5 ?m tantalum. A noise equivalent power density of 300 ?W/cm2 is achieved with 40×24 channels and a time response of 10 ms or 23 ?W/cm2 for 16×12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U.

Peterson, Byron J.; Parchamy, Homaira; Ashikawa, Naoko; Kawashima, Hisato; Konoshima, Shigeru; Kostryukov, Artem Yu.; Miroshnikov, Igor V.; Seo, Dongcheol; Omori, T.

2008-10-01

80

In situ microscopic observations of an electroless silver deposition process under high magnetic fields  

NASA Astrophysics Data System (ADS)

The mechanism of the morphological effect of magnetic fields on electroless silver deposition was investigated through in situ microscopic observation by using a periscope system that was developed on the basis of a confocal scanning laser microscope. At the growth front of a silver dendrite, under a 12 T magnetic field applied perpendicularly to the sample plane, a silver branch was grown straightly for a while; then, a certain length of the branch at the neighbor of the tip started moving rapidly and was bent in an integrated manner. As a result of the process, a dense silver dendrite in the shape of a vortex was formed. When the sample space was narrowed, the branch did not bend due to the increase in the static friction between the branch and the glass plates. Judging from these observations, the mechanism of the formation of a dense vortex dendrite was thought to be the effect of a Lorentz force acting on the branch due to the electric current flowing through the branch itself accompanied by the silver deposition and the copper dissolution reactions.

Hirota, Noriyuki; Hara, Soma; Uetake, Hiromichi; Nakamura, Hiroyuki; Kitazawa, Koichi

2006-01-01

81

Multi-photon excitation microscopy in intact animals  

PubMed Central

Two-photon excitation fluorescence microscopy (TPEFM) and backscattered-second harmonic generation (B-SHG) microscopy permit the investigation of the subcellular events within living animals, but numerous aspects of these experiments need to be optimized to overcome the traditional microscope geometry, motion, and optical coupling to the subject. This report describes a stable system for supporting a living instrumented mouse or rabbit during endogenous reduced nicotinamide adenine dinucleotide (NAD(P)H) and exogenous dye TPEFM measurements and B-SHG microscopy measurements. The system was a modified inverted Zeiss LSM510 microscope with a rotating periscope that converted the inverted scope in to an upright format, with the objective approximately 15 cm displaced from the center of the microscope base, allowing the easy placement of an instrumented animal. An Olympus 20x water immersion objective was optically coupled to the tissue, with out a cover glass, via a saline bath or custom hydrated transparent gel. The instrumented animals were held on a specially designed holder that poised the animal under the objective as well as permitted different ventilation schemes to minimize motion. Using this approach, quality images were routinely collected in living animals from both the peripheral and body cavity organs. The remaining most significant issue for physiological studies using this approach is motion on the micron scale. Several strategies for motion compensation are described and discussed.

Rothstein, Emily C.; Nauman, Michael; Chesnick, Scott; Balaban, Robert S.

2006-01-01

82

Evolution of design concepts for remotely maintainable equipment racks  

SciTech Connect

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.

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

1986-01-01

83

Development and results of a new methodology to perform focus group with preschool children on their beliefs and attitudes on physical activity.  

PubMed

The aim of this study is to develop and test a method to perform focus groups (FGs) and to elicit the subjective views of preschool-age children on physical activity and perceived kindergarten barriers to practice it. FGs have been held in three different kindergarten classes with 49 children who were 4-5 years old. Children were asked to draw themselves in their preferred way of playing and were asked few questions about their drawings to understand their behaviours and ideas. In class A and B, 67% and 75% of the children, respectively, drew sedentary plays (table and impersonation games). Children referred that the main obstacle to perform active games outside home/kindergarten was the parents' and teachers' perceived risk that they could be hurt or catch a cold. The children would like to have more table games in the kindergarten. 81% of children in class C drew active group games. All these children were well satisfied with their kindergarten environment and did not refer to any adults' fear regarding active play. This class teacher spent a lot of time to develop children's motor abilities through active games and often used the garden to let the children to play freely. The use of drawings to understand children's habits on physical activity has turned out to be a reliable and easy tool in preschool children. The different results obtained in the two children groups show the need to change the beliefs and the behaviours of teachers and parents who seem to be non-architectural "invisible" barriers to be knocked down. This protocol has been developed by ASL Brindisi within the framework of PERISCOPE's objective to develop new methodologies. PMID:21923291

Cammisa, Maria; Montrone, Rosa; Caroli, Margherita

2011-10-01

84

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

PubMed

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

Krentz, Andrew

2009-02-01

85

A lidar technique for adjusting aerosol model number densities close to the ocean surface  

NASA Astrophysics Data System (ADS)

With the Navy's interest in FLIR detectors at submarine periscope heights, it is important to get more detailed information on the atmospheric characteristics at FLIR wavelengths (3 to 5 and 8 to 12 microns) in the first few meters above the ocean. This information is particularly important for predicting the performance of electro-optical systems operating against skimmer-type missiles approaching a ship or submarine from beyond the horizon. A technique is introduced by which the total number density of the LOWTRAN 7 Navy Aerosol Model (NAM) (the kernel for the Naval Oceanic Vertical Aerosol Model) is adjusted to represent existing conditions close to the ocean surface. Measurements of bulk meteorological parameters at a reference height above the ocean surface are used to generate stability dependent logarithmic profiles of temperature and relative humidity. These profiles are used with the aerosol model to determine aerosol extinction and backscatter coefficient variations close to the ocean surface. Using the single-scatter lidar (light detection and ranging) equation, these parameters are then used to calculate a range compensated power, S(R), returned from scattering volumes at different heights in the modeled atmosphere. An iterative method is used by which the calculated S(R) values are adjusted to agree with the corresponding measured values obtained with a lidar operating at 1.06 microns and directed at the ocean over a slant path from an altitude of 10 meters. Examples of extinction coefficient variations with height above the ocean surface, calculated using the original and adjusted size distribution for different surface wind speed conditions and air-mass characteristics.

Paulson, M. R.; Hughes, H. G.

1990-12-01

86

Formation, Simulation and Restoration of Hypertelescopes Images  

NASA Astrophysics Data System (ADS)

This article first provides a historical and detailed introduction to the image formation models for diluted pupils array and their densified versions called hypertelescopes. We propose in particular an original derivation showing that densification using a periscopic setting like in Michelson's 20 - foot interferometer, or using inverted Galilean telescopes are fully equivalent. After a review based on previous reference studies (Tallon & Tallon-Bosc 1992; Labeyrie 1996; Aime 2008 and Aime et al. 2012), the introductory part ends with a tutorial section for simulating optical interferometric images produced by cophased arrays. We illustrate in details how the optical image formation model can be used to simulate hypertelescopes images, including sampling issues and their effects on the observed images. In a second part of the article, we address the issue of restoring hypertelescope images and present numerical illustrations obtained for classical (constrained Maximum Likelihood) methods. We also provide a detailed survey of more recent deconvolution methods based on sparse representations and of their spread in interferometric image reconstruction. The last part of the article is dedicated to two original and numerical studies. The first study shows by Monte Carlo simulations that the restoration quality achieved by constrained ML methods applied to photon limited images obtained from a diluted array on a square grid, or from a densified array (without spectral aliasing) on a grid, are essentially equivalent. The second study shows that it is possible to recover in hypertelescopes images quasi point sources that are not only far outside the clean field, but also superimposed on the replicas of other objects. This is true at least for the considered pupil array and in the limit of vanishing noise.

Mary, D.; Aime, C.; Carlotti, A.

2013-03-01

87

Synthesis and Design of Silicide Intermetallic Materials  

SciTech Connect

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.

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

1999-05-14

88

Imaging with hypertelescopes: a simple modal approach  

NASA Astrophysics Data System (ADS)

Aims: We give a simple analysis of imaging with hypertelescopes, a technique proposed by Labeyrie to produce snapshot images using arrays of telescopes. The approach is modal: we describe the transformations induced by the densification onto a sinusoidal decomposition of the focal image instead of the usual point spread function approach. Methods: We first express the image formed at the focus of a diluted array of apertures as the product R_0(?) X_F(?) of the diffraction pattern of the elementary apertures R_0(?) by the object-dependent interference term X_F(?) between all apertures. The interference term, which can be written in the form of a Fourier Series for an extremely diluted array, produces replications of the object, which makes observing the image difficult. We express the focal image after the densification using the approach of Tallon and Tallon-Bosc. Results: The result is very simple for an extremely diluted array. We show that the focal image in a periscopic densification of the array can be written as R_0(?) X_F(?/?), where ? is the factor of densification. There is a dilatation of the interference term while the diffraction term is unchanged. After de-zooming, the image can be written as ?2 X_F(?)R_0(? ?), an expression which clearly indicates that the final image corresponds to the center of the Fizeau image intensified by ?2. The imaging limitations of hypertelescopes are therefore those of the original configuration. The effect of the suppression of image replications is illustrated in a numerical simulation for a fully redundant configuration and a non-redundant one.

Aime, C.

2008-05-01

89

Active beam spectroscopy for ITER  

NASA Astrophysics Data System (ADS)

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 (0periscope, 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.

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

90

Open repair for juxtarenal aortic aneurysms.  

PubMed

Abdominal aortic aneurysms (AAAs) are classified as juxtarenal if their proximal extent is next to the origin of the renal arteries but does not involve them. An AAA is suprarenal if it extends above at least one renal artery and ends below the celiac axis. Juxtarenal AAAs need inter-renal or suprarenal clamping, with the aortic reconstruction usually made at the infrarenal level. Aneurysms requiring suprarenal clamping, often supraceliac, and the reconstruction (direct attachment or bypass) of at least one renal artery, are often defined as suprarenal AAAs. Endovascular aortic repair (EVAR) is feasible in most of cases of infrarenal AAAs and has been shown to be as effective as open repair (OR) in reducing aneurysm-related mortality and perioperative mortality with shorter length of stay. However, the feasibility of standard EVAR with an on-label use of commercially available devices is limited in the juxtarenal aorta. In our series, approximately, 20% to 30% of patients with an AAA are considered not eligible for standard EVAR owing to their anatomy, and in the most of the cases are patients with juxtarenal AAAs. Fenestrated and branched endografts and newer "off the shelf" techniques (such as chimney, periscope, sandwich) have been recently described, all with the purpose of widening the therapeutic range of EVAR to the treatment of aneurysms with involvement of renal and visceral arteries. However, safety, efficacy, long-term results, and cost-effectiveness of these expensive techniques have still to be carefully assessed. For these reasons, the OR is currently still considered the gold standard for treatment of juxtarenal AAAs, reserving endovascular strategies mainly for high-risk patients having comorbidities or other contraindications for conventional repair. If compared to open repair of infrarenal AAAs, juxtarenal AAA OR is technically more complex and might require specific organ-protection strategies in order to minimize ischemia-reperfusion injury to kidneys and visceral organs. Because of the complexity of the surgical procedure and of the multiple clinical problems, an optimal operative strategy for the treatment of juxtarenal AAAs has not been established yet. The choice of the surgical access, clamping level, methods of organ protection and their impact on renal, respiratiry, cardiac and gastrointestinal morbidity are still debated issues. PMID:23443588

Chiesa, R; Tshomba, Y; Mascia, D; Rinaldi, E; Logaldo, D; Civilini, E

2013-02-01

91

Obituary: Cornell H. Mayer, 1921-2005  

NASA Astrophysics Data System (ADS)

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 the observations were carried out and analyzed, many remained skeptical about the result and its interpretation in terms of a massive greenhouse effect, until the Mariner-II spacecraft fly-by in 1962, which put all such doubts to rest. Connie and his group continued to make radio observations of other planets and discovered a non-thermal centimeter wavelength emission from Jupiter. This led directly to work done at Caltech that demonstrated the existence of Van Allen-like belts around the planet. Being a superb engineer, Connie firmly believed that technology led to scientific discovery. Like others, he was preoccupied with the improvement of the sensitivity of radio astronomy receivers, and applied physics to new designs. In 1959, Connie collaborated with Charles Townes and his students at Columbia in the first application of the maser to astronomy. When Townes received the 1964 Nobel Prize for the invention of the maser, he asserted that Connie's desire to improve receiver sensitivity was influential in his work and shared a portion of his prize money with him. Connie's greatest contribution was in the study of non-thermal radio sources at very short wavelengths. Non-thermal sources were recognized by the fact that their flux density decreases with increasing frequency. If the emission mechanism were synchrotron radiation (as theorized in 1950), then the radiation should be linearly polarized up to a theoretical maximum of 70 percent. In 1949, John Bolton had identified a discrete radio source with the Crab Nebula optical counterpart. The optical radiation was known to contain a diffuse component with a featureless spectrum. The Russian astrophysicist Joseph Shklovsky boldly hypothesized that both the optical and radio emissions were due to the synchrotron mechanism. This implied that the optical radiation would be polarized, and Soviet scientists found it so in 1954. Soon after, the radio source Virgo A was matched with the peculiar galaxy M87, whose spectrally featureless optical jet was found to be polarized in 1956. Thus the crucial evidence in support of

Radhakrishnan, Venkataraman

2006-12-01