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1

Periscope  

NSDL National Science Digital Library

In this optics activity, learners build a spy tool to secretly view things over walls or around corners. Learners discover that the mirrors inside the periscope reflect light to help you see what's hidden behind a corner.

Boston, Wgbh

2003-01-01

2

Periscope  

NSDL National Science Digital Library

In this activity, learners construct a device that allows them to look over ledges or around corners. Use this activity to introduce learners to concepts related to optics, mirrors and how submarines use periscopes to see above water. Note: this activity requires the use of a saw, not included in the cost of materials.

Workshop, Watsonville E.

2011-01-01

3

Steerable zoom periscope  

Microsoft Academic Search

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

Michael O. Lidwell

1995-01-01

4

Periscope video ship classification  

Microsoft Academic Search

Automatic classification of surface ships by means of imaging sensors through the submarine's periscope is of interest to the naval underwater warfare center of the US Navy. In this paper we discuss a testbed designed for periscope video ship classification based on model-based automatic target recognition paradigm, will present the performance results for the application of some of the existing

Firooz A. Sadjadi; Jack Osullivan

1996-01-01

5

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

6

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

7

Periscope video ship classification  

NASA Astrophysics Data System (ADS)

Automatic classification of surface ships by means of imaging sensors through the submarine's periscope is of interest to the naval underwater warfare center of the US Navy. In this paper we discuss a testbed designed for periscope video ship classification based on model-based automatic target recognition paradigm, will present the performance results for the application of some of the existing algorithms and will present a sequential tree based technique for ship recognition.

Sadjadi, Firooz A.; OSullivan, Jack

1996-05-01

8

Autonomous Mobile Periscope System (AMPS)  

Microsoft Academic Search

The proliferation of diesel electric submarines has impacted undersea warfare (USW) world wide. They are acoustically nearly undetectable, but can be detected by their periscope or snorkel. Since the US Navy has no diesel electric submarine, the Autonomous Mobile Periscope System (AMPS) is being developed to meet the requirement for an inexpensive readily available periscope detection target for the training

Stan Rollins; Richard Knutson; Hung Vo; Steve Ebner

1998-01-01

9

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

10

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

11

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

12

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

13

A polarizing neutron periscope for neutron imaging  

NASA Astrophysics Data System (ADS)

Optical neutron polarizers like guides or benders destroy the collimation of a neutron beam due to multiple reflections or scattering. This makes them unsuitable for their use in polarized neutron radiography, because the beam collimation is essential to obtain high spatial resolution. We have developed a neutron polarizer based on the principle of an optical periscope with a zigzag double reflection on two parallel high- m supermirror polarizers. If the supermirrors are perfectly parallel and flat, the beam collimation is left unchanged by such a device. A first proof of concept version of this type of polarizer was built and tested. We expect to achieve a beam polarization of up to 99% with an improved version yet to be built.

Schulz, Michael; Böni, Peter; Calzada, Elbio; Mühlbauer, Martin; Neubauer, Andreas; Schillinger, Burkhard

2009-06-01

14

Polarized neutron radiography with a periscope  

NASA Astrophysics Data System (ADS)

The interaction of the magnetic moment of the neutron with magnetic fields provides a powerful probe for spatially resolved magnetisation measurements in magnetic materials. We have tested a periscope as a new type of polarizer providing neutron beams with a high polarization and a low divergence. The observed inhomogeneity of the beam caused by the waviness of the glass substrates was quantified by means of Monte-Carlo simulations using the software package McStas. The results show that beams of high homogeneity can be produced if the waviness is reduced to below 1.0·10-5 rad. Finally, it is shown that radiography with polarized neutrons is a powerful method for measuring the spatially resolved magnetisation in optically float-zoned samples of the weak itinerant ferromagnet Ni3Al, thereby aiding the identification of the appropriate growth parameters.

Schulz, Michael; Neubauer, Andreas; Mühlbauer, Martin; Calzada, Elbio; Schillinger, Burkhard; Pfleiderer, Christian; Böni, Peter

2010-01-01

15

PERISCOPE: An Online-Based Distributed Performance Analysis Tool  

NASA Astrophysics Data System (ADS)

This paper presents PERISCOPE - an online distributed performance analysis tool that searches for a wide range of performance bottlenecks in parallel applications. It consists of a set of agents that capture and analyze application and hardware-related properties in an autonomous fashion. The paper focuses on the Periscope design, the different search methodologies, and the steps involved to do an online performance analysis. A new graphical user-friendly interface based on Eclipse is introduced. Through the use of this new easy-to-use graphical interface, remote execution, selection of the type of analysis, and the inspection of the found properties can be performed in an intuitive and easy way. In addition, a real-world application, namely, the GENE code, a grand challenge problem of plasma physics is analyzed using Periscope. The results are illustrated in terms of found properties and scalability issues.

Benedict, Shajulin; Petkov, Ventsislav; Gerndt, Michael

16

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

17

A neutron optical periscope used for neutron imaging  

NASA Astrophysics Data System (ADS)

A standard neutron guide is ill suited for neutron imaging, because reflections in the guide destroy the collimation of the neutron beam and let the cross-section of the neutron guide act as a divergent area source. Good neutron imaging installations use a flight tube instead, but with direct sight they also have a large background of gamma radiation and fast and epithermal neutrons. With the availability of high-m super mirrors, it has now become possible to build a neutron optical periscope that eliminates direct sight with two plain optical reflections only, without destroying the beam collimation ratio. At the FRM II reactor of Technische Universität München, several prototypes have been built and tested. Several neutron periscopes will be installed during the upgrade of the ANTARES neutron imaging facility in 2009/2010.

Schillinger, Burkhard; Böni, Peter; Breunig, Christian; Calzada, Elbio; Leroy, C.; Mühlbauer, Martin; Schulz, Michael

2009-06-01

18

Submarine periscope thermal imaging: its evolution in the UK  

NASA Astrophysics Data System (ADS)

The first submarine periscope to carry a thermal imaging sensor started sea trials in 1978. As a leading EO company and the sole supplier of periscopes to the Royal Navy since 1917, Pilkington Optronics (Barr & Stroud) has led the evolution of this technology in the UK. As is often the case, the evolutionary path has been IR detector technology- led. The first operational periscope TI system (1981) used a serial/parallel array of first generation photoconductive detectors operating in the LWIR (8 - 12 micrometer) waveband. The advent of SPRITE detectors in the 1980s opened the way to greatly improved performance within a reduced space volume, culminating in 1993 with the entry into fleet service of the SPRITE-based IR028 modular system for Vanguard, the new class of RN ballistic submarines. Today, second generation focal plane array detectors, along with the concept of the non-hull penetrating optronics mast, are ready to revolutionize periscope TI. The Pilkington Optronics CM10 Optronics Mast, presently under development, has been bid for the next class of RN submarines, Trafalgar Batch 2. CM10 exists in two versions, allowing the user to choose the operational waveband most suited to his operational needs. The sensor in the LWIR version is the PO high definition thermal imager (HDTI), which makes optimum use of SPRITEs to achieve very high performance within a compact space. The MWIR version features dual-band (TV plus 3 - 5 micrometer) optics viewing through a single pressure window; the TI sensor is based on a microscanned CMT FPA, yielding high spatial resolution and thermal sensitivity with small aperture optics.

Armstrong, George R.

1996-06-01

19

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

NASA Technical Reports Server (NTRS)

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

Ames, Lawrence L. (Inventor)

2006-01-01

20

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

21

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

PubMed

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

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

2014-07-01

22

Periscope-Camera System for Visible and Infrared Imaging Diagnostics on TFTR.  

National Technical Information Service (NTIS)

An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect vacuum vessel internal structures in both vis...

S. S. Medley D. L. Dimock S. Hayes D. Long J. L. Lowrence

1985-01-01

23

Design study of a visible/infrared periscope for intense radiation applications using reflective optics  

NASA Astrophysics Data System (ADS)

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 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 International Thermonuclear 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 300-2000 °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 °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 article.

Medley, S. S.

1999-01-01

24

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

25

Representing distributed cognition in complex systems: how a submarine returns to periscope depth.  

PubMed

This paper presents the Event Analysis of Systemic Teamwork (EAST) method as a means of modelling distributed cognition in systems. The method comprises three network models (i.e. task, social and information) and their combination. This method was applied to the interactions between the sound room and control room in a submarine, following the activities of returning the submarine to periscope depth. This paper demonstrates three main developments in EAST. First, building the network models directly, without reference to the intervening methods. Second, the application of analysis metrics to all three networks. Third, the combination of the aforementioned networks in different ways to gain a broader understanding of the distributed cognition. Analyses have shown that EAST can be used to gain both qualitative and quantitative insights into distributed cognition. Future research should focus on the analyses of network resilience and modelling alternative versions of a system. PMID:23510256

Stanton, Neville A

2014-03-01

26

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

27

Periscope Design and Testing for Remote Viewing Inside DIII-D  

NASA Astrophysics Data System (ADS)

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 cm-2, while ITER is expected to produce a neutron fluence of order 10^21 cm-2. Thus, optical fibers are not a viable option for remote viewing of ITER, and alternative methods need to be pursued. As part of disruption mitigation studies at DIII-D, we have designed a periscope system comprised of mirrors and a series of Nikon 100 mm f/2.8 camera lenses that relay an image of the plasma viewed through a window flange to a fast-framing CMOS camera detector. We present preliminary measurements of image quality and light throughput of the optical system.

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

2006-10-01

28

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

2014-01-01

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

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

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

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

33

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

34

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

35

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

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

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

36

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

37

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

38

Detection of small targets in a marine environment using laser radar  

Microsoft Academic Search

Small maritime targets, e.g., periscope tubes, jet skies, swimmers and small boats, are potential threats for naval ships under many conditions, but are difficult to detect with current radar systems due to their limited radar cross section and the presence of sea clutter. On the other hand, applications of lidar systems have shown that the reflections from small targets are

Gerard J. Kunz; Herman H. P. T. Bekman; Koen W. Benoist; Leo H. Coen; Johan C. van den Heuvel; Frank J. M. van Putten

2005-01-01

39

1990 waste tank inspection program  

SciTech Connect

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

McNatt, F.G.

1990-01-01

40

A multi-angle spectrometer for automatic measurement of plant canopy reflectance spectra  

Microsoft Academic Search

The paper describes the design and operation of a multi-angle spectrometer (MAS) for automatic measurement of near-field spectral reflectances of plant canopies at hourly intervals. A novel feature of the instrument is a rotating periscope connected to a spectrometer via a fiber optic cable. Canopy reflectances are calculated for multiple view azimuths, at a single zenith angle from measurements of

Ray Leuning; Dale Hughes; Paul Daniel; Nicholas C. Coops; Glenn Newnham

2006-01-01

41

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

42

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

43

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

Microsoft Academic Search

The Sight Integrated Ranging Equipment (SIRE) incorporates an eyesafe laser rangefinder into the M-36 periscope used in tactical armored vehicles, such as the Commando Stingray light tank. The SIRE unit provides crucial range data simultaneously to the gunner and fire control computer. This capability greatly reduces 'time-to-fire', improves first-round hit probability, and increases the overall effectiveness of the vehicle under

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

1991-01-01

44

ATTICA family of thermal cameras in submarine applications  

Microsoft Academic Search

Optronics Mast Systems (US: Photonics Mast Systems) are electro-optical devices which enable a submarine crew to observe the scenery above water during dive. Unlike classical submarine periscopes they are non-hull-penetrating and therefore have no direct viewing capability. Typically they have electro-optical cameras both for the visual and for an IR spectral band with panoramic view and a stabilized line of

Gunther Kuerbitz; Joerg Fritze; Jens-Rainer Hoefft; Berthold Ruf

2001-01-01

45

Passive and periodically ultra fast RF-photonic spectral scanner  

NASA Astrophysics Data System (ADS)

In this paper we present passive photonic device performing periodic and ultra fast spectral analysis of RF signals modulated on optical carrier. The spectral scanning is demonstrated in two approaches. First by passing the light through a couple of special bulk periscopes that split the beam into a set of parallel channels or combine a set of channels into one beam. One surface of each periscope is coated with high reflectivity coating such that the set of parallel beams travel several times through the structure due to their partial back reflection in each passage through the periscope. In each passage in the system the channel experience different delay in comparison with the original signal. This relative delay is accumulative and it is generated by placing glass bars with different length for each one of the channels. This structure realizes Finite Impulse Response (FIR) filter that performs the spectral scanning. The second approach involves similar configuration but it is realized with fibers and Y couplers rather than bulk optics. In this case the filter that performs the spectral scanning is an Infinite Impulse Response (IIR) filter having much sharper spectral sampling capability.

Zalevsky, Zeev; Shemer, Amir; Mendlovic, David; Zach, Shlomo

2006-09-01

46

Enhancements of remote sensing for vehicle emissions in tunnels  

SciTech Connect

The University of Denver's remote sensing system for vehicle exhaust has been successfully adapted to the measurement of vehicle emissions in a tunnel environment. Two studies conducted at the Fort McHenry Tunnel in Baltimore, MD and the Tuscarora Mountain Tunnel located west of Harrisburg, PA on the Pennsylvania Turnpike are described. The difficulties associated with remote sensing in a tunnel environment have led to a number of improvements in the remote sensing technology. The successful use of a prototype periscope system is described and evaluated along with the first-time measurements of dual lane traffic. 9 refs., 4 figs., 3 tabs.

Bishop, G.A.; Zhang, Y.; McLaren, S.E.; Guenther, P.L.; Beaton, S.P.; Peterson, J.E.; Stedman, D.H. (Univ. of Denver, CO (United States)); Pierson, W.R. (Desert Research Inst., Reno, NV (United States)); Knapp, K.T.; Zweidinger, R.B. (Environmental Protection Agency, Research Triangle Park, NC (United States)) (and others)

1994-02-01

47

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

48

A model for the submarine depthkeeping team  

NASA Technical Reports Server (NTRS)

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

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

1981-01-01

49

Wideband protection filter (WPF) integrated within optical systems  

NASA Astrophysics Data System (ADS)

Laser radiation may lead to permanent damage of the human eye when it is exposed to high power irradiation, especially when using magnifying optics such as binoculars, sights or periscopes. Into such an optical system we integrated a novel passive solid-state threshold-triggered Wideband Protection Filter (WPF) that blocks the transmission only if the power exceeds a certain threshold. At input powers below threshold, the filter has high transmission over the whole spectral band. However, when the input power exceeds the threshold power, transmission is decreased dramatically. We demonstrate the WPF integration within a typical optical system and the influence of system parameters on the protection capability of the filter.

Ritt, G.; Eberle, B.; Ebert, R.; Fisher, T.; Nemet, B.; Oron, M.; Donval, A.

2008-10-01

50

Infrared technology XII; Proceedings of the Meeting, San Diego, CA, Aug. 19, 20, 1986  

SciTech Connect

The present conference on IR sensor technology considers topics in IR imaging, the simulation and modeling of IR images, IR technology developments in Britain, and novel IR sensor applications. Attention is given to an imaging spectrometer for Mars investigation, the Space Shuttle IR Imaging Experiment, an IR scene composer for electronic vision applications, and practical results for sampling effects in CdHgTe focal-plane arrays. Also discussed are a dual-waveband imaging radiometer, thermal imaging sensors for submarine periscopes, the structure of the extended emission in the IR celestial background, and novel long-path transmissometry.

Spiro, I.J.; Mollicone, R.A.

1986-01-01

51

A survey of ATL-compatible radiometer antennas  

NASA Technical Reports Server (NTRS)

A survey was made of antennas suitable for remote sensing of the earth's surface, in particular the world ocean, by means of microwave radiometers operating in the 1 to 26 GHz frequency region and carried on board the shuttle-launched advanced technology laboratory. Array antennas are found to be unattractive and unsuited to the task. Reflectors, including Cassegrain and offset types, as well as horn-reflectors are possible candidates but all have shortcomings which impair the accuracy of measurement. Horns of the corrugated type have excellent electrical characteristics. Although they are physically very large and will require development of suitable deployment mechanisms, they appear to be valid candidates for the task. The evolution of the periscope antenna is outlined, and it is shown to possess nearly ideal electrical characteristics for the intended application. Its only shortcoming is that the feed horn creates aperture blocking; there is no blocking due to struts or any other source. The periscope antenna is recommended for ATL radiometry.

Love, A. W.

1975-01-01

52

System performance model and error budget for MAXIM  

NASA Astrophysics Data System (ADS)

The proposed Micro-Arcsecond X-ray Imaging Mission (MAXIM) uses an array of spacecraft containing grazing incidence optics to create and acquire an image on a distant detector spacecraft. Among the technical challenges facing the mission, maintaining an acceptably small wavefront error in the optical system is addressed in this paper. Starting with a performance model for the observatory and both analytically- and raytrace-based optical sensitivities to misalignment and figure error, an error budget is constructed that includes the effects of the individual optical surfaces, the alignment of the optical elements within the 4-mirror periscope sub-assemblies, and the relative alignment of the many periscopes that make up the MAXIM optical imaging system. At this stage of conceptual development, the allocations to different sub-systems that affect wavefront error is based on the philosophy of "spreading the pain" associated with performance requirements of the contributing elements. The performance model and error budget become tools with which to explore different architectures and requirements allocations as the mission concept develops.

Leitch, Jim W.; Lieber, Michael D.; Gallagher, Dennis J.; Gendreau, Keith C.; Cash, Webster C.; Shipley, Ann F.

2004-10-01

53

Enhanced core charge exchange recombination spectroscopy system on Joint European Torus  

NASA Astrophysics Data System (ADS)

Charge exchange spectroscopy is a key diagnostic on the Joint European Torus for radial profiles of ion temperature, toroidal rotation, and impurity densities. This article describes the current status and the improvements made over the last five years. The current system consists of two periscopes looking at one of the two banks of neutral heating beams, ~90 optical fibers defining viewing directions, and seven spectrometers with charge-coupled device (CCD) cameras. The upgrade has involved replacement of the two periscopes and windows, a doubling of the number of optical fibers (plasma viewing directions), new cameras for the existing spectrometers, improvements to the throughput and long-term stability of the five existing spectrometers, and the addition of two new high-throughput spectrometers with their CCD cameras from ORNL. This work has culminated in improved spatial resolution, increased sensitivity of all the plasma viewing channels (for some by a factor of ~3 or more), and enhanced time resolution from 50 to around 10 ms.

Negus, C. R.; Giroud, C.; Meigs, A. G.; Zastrow, K.-D.; Hillis, D. L.

2006-10-01

54

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

NASA Astrophysics Data System (ADS)

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

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

2008-07-01

55

Design and Validation of a Temperature Measurement System for the Movable Flaps on the IXV  

NASA Astrophysics Data System (ADS)

An infrared camera will be part of the advanced measurement system on the re-entry experimental vehicle IXV. The purpose of the instrument is the thermal mapping of the movable rear side body flaps of the vehicle. A wide angle front optic is used in combination with a periscope system located on the upper rear part of the IXV base, which allows imaging of one of the flaps within the complete angular range of -21° - +19°. The camera uses multicolour pyrometry measurement for absolute temperature measurement with an accuracy exceeding 0.5 %. For redundancy reasons and post flight validation the flap will also be equipped with thermocouples as an independent temperature measurement. The high temperature encapsulated thermocouples will be routed along the body flap ribs and will enter the vehicle inside the flap support structures. A comb system is used for the length compensation coming from the flap movement.

Walz, S.; Roesgen, T.; Periera, C.; Handrick, K.; Steinacher, A.

2011-08-01

56

High Resolution IR Imaging for Alcator C-Mod  

NASA Astrophysics Data System (ADS)

We are upgrading the infrared imaging system for divertor heat load studies on Alcator C-Mod by adding a new FLIR SC8303HD camera. The new camera is capable of 1344x784 pixel full frame resolution with 14-bit images at 130 Hz. Faster rates are possible by sub-windowing on the image. The new camera uses full camera link interface over fiber optics from the test cell to the control room, and the resulting data acquisition handles an image stream of 260 Mbytes/second straight to disk. At first we will employ a silicon wafer beam splitter, to enable measurements with both the new and old cameras simultaneously with the existing IR periscope. Initial data from the new camera and the parallel development of real-time imaging software for later use of this hardware on the W7-X stellarator will be discussed.

Wurden, G. A.; Terry, J. L.

2012-10-01

57

Optical system design, analysis, and production for advanced technology systems; Proceedings of the Meeting, Innsbruck, Austria, Apr. 15-17, 1986  

NASA Technical Reports Server (NTRS)

The present conference considers topics in the fields of optical systems design software, the design and analysis of optical systems, illustrative cases of advanced optical system design, the integration of optical designs into greater systems, and optical fabrication and testing techniques. Attention is given to an extended range diffraction-based merit function for lens design optimization, an assessment of technologies for stray light control and evaluation, the automated characterization of IR systems' spatial resolution, a spectrum of design techniques based on aberration theory, a three-field IR telescope, a large aperture zoom lens for 16-mm motion picture cameras, and the use of concave holographic gratings as monochomators. Also discussed are the use of aspherics in optical systems, glass choice procedures for periscope design, the fabrication and testing of unconventional optics, low mass mirrors for large optics, and the diamond grinding of optical surfaces on aspheric lens molds.

Fischer, Robert E. (editor); Rogers, Philip J. (editor)

1986-01-01

58

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

NASA Technical Reports Server (NTRS)

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

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

1984-01-01

59

Thermochromic liquid crystal temperature measurements through a borescope imaging system  

NASA Astrophysics Data System (ADS)

Thermochromic liquid crystals (TLCs) have proven to be a valuable tool for the collection of full-field, high-resolution heat transfer data. This paper presents an extension of previously developed calibration techniques to a simplified transonic linear cascade for a highly cambered turbine blade geometry. This required the introduction of miniature periscopes to image the measurement surfaces. The procedures and equipment used to ensure high-accuracy wide-band TLC measurements are presented. These included a geometry-matched calibration device, mechanisms to accurately position the borescope imaging optics, an algorithm to automatically divide the imaging region into a large number of calibration subregions (termed as cells), and algorithms to correct for geometric and optical image distortions. The cell calibration approach is shown to halve calibration times and dramatically reduce memory requirements when compared to a pixel-by-pixel calibration. The results of an extensive validation study are presented.

Kodzwa, Paul M.; Elkins, Christopher J.; Mukerji, Debjit; Eaton, John K.

2007-10-01

60

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

61

Magnify It!  

NSDL National Science Digital Library

In this lesson, students will learn that there are limits to what the eye can see and that a magnifying glass can help extend those limits. Students may have been exposed to optical technology such as glasses, magnifying lenses, or even periscopes, microscopes, and telescopes. This lesson aims to channel the inventive energy of students to increase their awareness and purposeful use of tools. They will view objects of various sizes from several viewing distances to discover that their visual field is limited. Students will record what they see and will compare their observations with classmates in an open, nonjudgmental forum. They will have the opportunity to speculate about and experiment freely with magnifying glasses and will also conduct more structured experiments.

62

Submarine imaging systems: developing improved capabilities and technologies  

NASA Astrophysics Data System (ADS)

The US Navy sumbmarine Imaging and Electronic Warfare Program Office, NAVSEA PMS435, is constantly pursuing new technologies and enhanced capabilities in order to allow the submarine fleet to meet quick reaction mission requirements, anticipated future threats and to provide for improvements in overall situational awareness. NAVSEA PMS 435 is actively pursuing the development of applicable technologies and capabilities in the following areas: Periscope Headwindow Watershedding, Mid-Wave Infrared, Low Cost Expendable Imaging Sensors (LCES), Auto Detection and Tracking (ADAT), Auto Target Recognition (ATR), 360 Degree Imaging Systems, and Image Stitching Algorithms. This presentation provides a status of where NAVSEA PMS 435 is in regard to the development of these technologies and provides an opportunity to share ideas as to how they might be more effectively developed by leveraging information and other resources available in other government agencies, commercial partners and academia.

Duryea, David M.; Lindstrom, Carl E.; Sayegh, Riad

2008-05-01

63

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

NASA Technical Reports Server (NTRS)

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

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

2012-01-01

64

Physical activity and play in kindergarten age children.  

PubMed

PERISCOPE project assesses factors promoting or preventing obesity development in early age. A specific aim is to assess preschool children's physical activity habits in three different European countries. PERISCOPE has been implemented in 1094 children attending kindergartens in Denmark, Italy and Poland. The parents' and children's physical activity habits and attitudes assessed by a questionnaire filled by the parents. Overweight and obesity assessed by Cole's BMI cut-off points. Statistical analysis performed by ?(2) test and the test of proportion. Denmark shows the lowest rate (14.6 %) of overweight, followed by Poland (17.1%), while Italy shows the highest (21.2 %) (p < 0.0001). The Polish families show the highest rate of walking from home to kindergarten and back, followed by the Italians and, lastly, the Danish ones (p < 0.001). Almost all the Danish and Polish children, but only the 50.1 % of the Italians play outside (p < 0.001). During the weekdays, 34.9 % of Polish children, 22.2 % of Italians and 19.8 % of the Danish play outside more than one hour a day (p < 0.0001). During the weekend, 91.1 % of Polish children, 86.7 % of Danish children, but only 54.4 % of Italians play outside more than one hour (p < 0.0001). 53.5 % of Danish children, 31.9 % of Polish children, and 18.2 % of Italian ones practice sport (p < 0.0001). Danish children are the most active, the Polish are in the middle and the Italians are the least active. The difference in infrastructures (safety of walking streets, access to playgrounds/parks, etc.) can play an important role, in addition to cultural and social family characteristics, to the development of overweight. PMID:21923297

Caroli, Margherita; Malecka-Tendera, Ewa; Epifani, Susi; Rollo, Rodolfo; Sansolios, Sanne; Matusik, Pawel; Mikkelsen, Bent E

2011-10-01

65

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

66

Enhancements of remote sensing for vehicle emissions in tunnels  

SciTech Connect

The University of Denver in cooperation with the Desert Research Institute, U.S. EPA, and General Motors Corporation have successfully adapted the University of Denver's remote sensing system for vehicle exhaust to the measurement of vehicle emissions in a tunnel environment. Two studies conducted at the Fort McHenry Tunnel in Baltimore, MD and the Tuscarora Mountain Tunnel located west of Harrisburg, PA on the Pennsylvania Turnpike are described. The difficulties associated with remote sensing in a tunnel environment have led to a number of improvements in the remote sensing technology. Due to logistics and restrictions on placement of equipment in the Fort McHenry tunnel, a prototype periscope system was employed to optimize the height of the remote sensor's infrared beam path relative to vehicle exhaust plumes. At the Tuscarora Tunnel, first-time measurements of dual lane traffic were conducted using a single source and detector and two cameras for vehicle identification. This precluded the normal practice of directing traffic into a single lane which can alter normal driving patterns.

Bishop, G.A.; Zhang, Y.; McLaren, S.E.; Guenther, P.L.; Beaton, S.P.

1994-01-01

67

Optical multiple access intersatellite links  

NASA Astrophysics Data System (ADS)

The feasibility of an optical implementation of a multiple access medium data rate data relay service on the timescale of Euro-DRS was assessed. The service requirements for the feasibility study are based on the service which, in existing or planned systems, is implemented at S band. The system should communicate simultaneously with up to 8 LEO users in orbits of radii up to 7400 km providing 8 independently agile links. On each link, it should communicate at up to 2Mb/sec, at bit error rates of 10 to the minus 6th power in the return direction (LEO to GEO). A design concept for the GEO central node was produced. Mass and power estimates were evaluated and a preliminary spacecraft accommodation study performed. The system weighs 130 kg and has a power consumption of 300 W. The optical subsystem occupies a 75 x 75 x 30 cm volume on the top floor of the spacecraft. A number of trade-offs were identified and performed in reaching the final system configuration. The system should have 1 telescope system per user, a periscope mirror configuration for coarse pointing, a single telescope for both transmit and receive, and the use of both 0.8 micron for the LEO-GEO link and 1.3 micron for GEO-LEO.

Grant, M. A.; Matthews, N. F.; Robson, D.

1988-03-01

68

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

69

Laboratory testbeds for broadband x-ray interferometry  

NASA Astrophysics Data System (ADS)

NASA's Strategic Plan for Space Sciences currently envisions a mission capable of resolving the event horizons of supermassive black holes, with imaging-spectroscopy capabilities at angular resolutions better than 0.1 microarcsecond. To achieve this goal, the Micro-Arcsecond X-ray Imaging Mission (MAXIM), a broadband X-ray interferometer, is currently under study. Ground-based proof-of-concept efforts include experiments to demonstrate the feasibility of X-ray interferometry with simple optics. We describe here recent advances in laboratory testbeds, at the University of Colorado and at NASA's Goddard Space Flight Center, that essentially replicate Young's double-slit experiment at X-ray energies. A typical apparatus employs four flat mirrors arranged in periscope pairs, with each pair illuminated at grazing incidence by a slit. We discuss the salient features of these experiments, technical hurdles such as metrology and line-of-sight issues, the successful detection of fringes at wavelengths as short as the Al Kalpha line at 8.35 Angstroms, and future upgrades of our facilities.

Arzoumanian, Zaven; Gendreau, Keith C.; Cash, Webster C.; Shipley, Ann F.; Queen, Steven Z.

2004-10-01

70

Onsager Regression in phase-space resolved ion fluctuations.  

NASA Astrophysics Data System (ADS)

Onsager regression is the hypothesis that there is no difference between a fluctuation and a linear excitation. It implies that there is a connection between certain correlation functions and the linear response function. We explore this connection by comparing phase-space resolved correlation functions for ion fluctuations to linear response functions for the ion response. The data come from two-point correlation functions measured in a singly ionized Argon discharge plasma using laser-induced fluorescence. The experiments are performed in a plasma cylinder of density 10^9 cm-3 and a uniform magnetic field of 1kG. The LIF laser is aligned parallel to the magnetic field and two periscope detection systems are aligned to view points on the beam separated by a variable distance along the magnetic field. LIF measurements of fluctuations are not able to directly view the presence of particle discreteness because optical pumping and collisions make it improbable that there will be even one detected photon per metastable ion. Thus, all the cross-correlation results have to do with collective effects (modes). Nevertheless, there is a kinetic ``free-streaming'' part that is a significant part of the fluctuations. Although it is not at all clear that a linear theory should apply to these fluctuations because nonlinear correlations are evident in the bicoherence, and there should be trapped particle effects, we find that the kinetic component also can be described by an impulse response function

Skiff, Fred

2007-11-01

71

Enhanced dendritic activity in awake rats  

PubMed Central

Almost nothing is known about dendritic activity in awake animals and even less about its relationship to behavior. The tuft dendrites of layer 5 (L5) pyramidal neurons lie in layer 1, where long-range axons from secondary thalamic nuclei and higher cortical areas arrive. This class of input is very dependent on active thalamo-cortical loops and activity in higher brain areas and so is likely to be heavily influenced by the conscious state of the animal. If, as has been suggested, the dendrites of pyramidal neurons actively participate in this process, dendritic activity should greatly increase in the awake state. Here, we measured calcium activity in L5 pyramidal neuron dendrites using the “periscope” fiberoptic system. Recordings were made in the sensorimotor cortex of awake and anesthetized rats following sensory stimulation of the hindlimb. Bi-phasic dendritic responses evoked by hindlimb stimulation were extremely dependent on brain state. In the awake state, there was a prominent slow, delayed response whose integral was on average 14-fold larger than in the anesthetized state. Moreover, the dramatic increases in dendritic activity closely correlated to the strength of subsequent hindlimb movement. These changes were confined to L5 pyramidal dendrites and were not reflected in the response of layer 2/3 (L2/3) neurons to air-puff stimuli in general (which actually decreased in the awake state). The results demonstrate that the activity of L5 pyramidal dendrites is a neural correlate of awake behavior.

Murayama, Masanori; Larkum, Matthew E.

2009-01-01

72

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

73

Development of imaging bolometers for magnetic fusion reactors (invited).  

PubMed

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 microm, 256 x 360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF(2) optics and an aluminum mirror. The IRVB foil is 7 cm x 9 cm x 5 microm tantalum. A noise equivalent power density of 300 microW/cm(2) is achieved with 40 x 24 channels and a time response of 10 ms or 23 microW/cm(2) for 16 x 12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U. PMID:19044463

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

2008-10-01

74

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

NASA Technical Reports Server (NTRS)

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

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

1980-01-01

75

Feasibility of a self-nulling beam combiner using no external phase inverter  

NASA Astrophysics Data System (ADS)

Space-based nulling interferometers will play a major role in the search for exoplanets, as both NASA and ESA plan missions for the near future. Current architectures produce the requisite broadband ? phase shift in one arm of each nulling telescope pair by means of a system of "field flip" optics that may involve one of a number of sophisticated technologies (periscope, phase plates, through-focus, or other). The two beams, of equal intensity but conjugate phase, are then combined, perhaps in a modified Mach-Zehnder (MMZ) or similar beam combiner of high configurational symmetry. A novel approach has recently been proposed, however, in which the achromatic ? phase shift is supplied by two applications of the innate ?/2 phase shift between transmitted and reflected beams in a beam splitter. This simply requires using the traditionally bright output port of the MMZ as a nulled port; adaptive nulling can be used to ease the tolerances on matching the moduli of reflection and transmission coefficients. The rather substantial systems benefit that accrues is that the external phase shifting ("field flipping") optics may be entirely eliminated. Here, I discuss the feasibility of this "self-nulling" beam combiner scheme.

Bloemhof, E. E.

2005-08-01

76

Detection of small targets in a marine environment using laser radar  

NASA Astrophysics Data System (ADS)

Small maritime targets, e.g., periscope tubes, jet skies, swimmers and small boats, are potential threats for naval ships under many conditions, but are difficult to detect with current radar systems due to their limited radar cross section and the presence of sea clutter. On the other hand, applications of lidar systems have shown that the reflections from small targets are significantly stronger than reflections from the sea surface. As a result, dedicated lidar systems are potential tools for the detection of small maritime targets. A geometric approach is used to compare the diffuse reflection properties of cylinders and spheres with flat surfaces, which is used to estimate the maximum detectable range of such objects for a given lidar system. Experimental results using lasers operating at 1.06 ?m and 1.57 ?m confirm this theory and are discussed. Small buoys near Scheveningen harbor could be detected under adverse weather over more than 9 km. Extrapolation of these results indicates that small targets can be detected out to ranges of approximately 20 km.

Kunz, Gerard J.; Bekman, Herman H. P. T.; Benoist, Koen W.; Coen, Leo H.; van den Heuvel, Johan C.; van Putten, Frank J. M.

2005-08-01

77

Development of imaging bolometers for magnetic fusion reactors (invited)  

SciTech Connect

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 {mu}m, 256x360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF{sub 2} optics and an aluminum mirror. The IRVB foil is 7 cmx9 cmx5 {mu}m tantalum. A noise equivalent power density of 300 {mu}W/cm{sup 2} is achieved with 40x24 channels and a time response of 10 ms or 23 {mu}W/cm{sup 2} for 16x12 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 [National Institute for Fusion Science, Toki 509-5292 (Japan); Kawashima, Hisato; Konoshima, Shigeru [Japan Atomic Energy Agency, Naka 311-0193 (Japan); Kostryukov, Artem Yu.; Miroshnikov, Igor V. [St. Petersburg State Technical University, St. Petersburg 195251 (Russian Federation); Seo, Dongcheol [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Omori, T. [Graduate University for Advanced Studies, Toki 509-5292 (Japan)

2008-10-15

78

PropHAn: horizontal propagation sensor for interferometry at Dome C  

NASA Astrophysics Data System (ADS)

To prepare long baseline interferometric arrays with large telescopes, at Dome C on the Antarctic plateau, we have to know the effect of the strong turbulent surface layer on the wave front propagation as sensed by two telescopes. The main limit of long baseline interferometer is the phase fluctuations, induced by the optical turbulence above each telescope and towarsds the focal beam combiner. PropHAn (Horizontal Propagation in Antarctica) is an instrument to study the optical turbulence effect on the horizontal propagation. PropHAn is designed to retrieve the phase fluctuations between two different horizontal paths of a coherent laser beam. It is a Michelson periscopic interferometer with a variable baseline from 10 cm up to 1 m. The fringe pattern is recorded on a fast CCD camera to freeze the turbulent motions. The main goal of PropHAn is to test a simple interferometric table in Antarctic conditions, and to provide statistics on the turbulent coherence time and the differential pistonmode for a 1 m baseline. These results, in complement with the results provided by DIMM, C2N balloons profiles and Single Star Scidar measurements, would be required to design long baseline interferometers and fringe tracker at Dome C.

Trinquet, Hervé; Vakili, Farrokh; Petitjean, Guillaume; Jeanneaux, François; Daban, Jean-Baptiste; Vernin, Jean

2008-07-01

79

Multiple-input fiber optic imaging system  

NASA Astrophysics Data System (ADS)

Fiber optic imaging bundles have been used for a number of years in medical and industrial remote sensing applications. Several NASA applications (such as Orbiter payload alignment for berthing/unberthing operations and Space Station Freedom construction) requiring multiple views have been identified. This paper reports on some of the proposed systems and on an optical switch which can connect any one of multiple imaging bundles to a single camera. The switch uses a rotating offset prism and collimated optics to relay the image to the camera. The offset prism merely displaces the image without dispersing, thereby acting as a periscope. By operating the prism in collimated light any one of several imaging bundles can be selected with negligible sensitivity to rotational precision. Located in the Orbiter payload bay, the input view would be selected by driving motors to rotate the prism. The same motors, used in a feedback mode, would be used to `stop-down' the input optics. Detailed mechanical and optical designs are presented as well as results from developmental studies.

Faller, Carlton S.; Ehrhardt, Mark W.; Monroe, Stanley E.; Juday, Richard D.

1993-09-01

80

Lost fast ion diagnostics by a scintillator probe  

NASA Astrophysics Data System (ADS)

For lost fast ion studies in confined plasmas, a scintillator type lost ion probe is installed into the Large Helical Device (LHD). The scintillator probe can measure the pitch angle and energy of fast ions simultaneously. During the neutral beam (NB) injection into the LHD, the fast ion profile at the edge plasma was measured using the scintillator probe. The measured results will be compared with fast ion orbits estimated from the deposition profile of NBs. While the self-sustained detachment plasma has been observed, the measured lost ion signal level became quite lower, compared with that before the self-sustained one occurred. The frequency of lost ion signal with 5 kHz disappeared during the self-sustained detachment phase. Taking into account the changes in the deposition of NBs, lost fast ion behaviors would be discussed. The new scintillator probe has been designed and will be installed into the different location of the LHD. A periscope with eyepiece, relay, and objective lenses is employed to transmit the scintillator light to an image intensified charge coupled device camera and 3x3 photomultiplier arrays. The design and first result using new scintillator probe will be presented.

Nishiura, Masaki; Kubo, N.; Murakami, S.; Osakabe, M.; Darrow, D. S.

2005-10-01

81

History of remote operations and robotics in nuclear facilities. Robotics and Intelligent Systems Program  

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.

1992-05-01

82

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

83

Flat panels in future ground combat vehicles  

NASA Astrophysics Data System (ADS)

The efforts of the design team for the Crewman's Associate Advanced Technology Demonstration (CA ATD) and its use of advanced display concepts is discussed. This team has the responsibility of identifying future technologies with the potential for maximizing human- machine interaction for incorporation into future crew station designs for ground combat vehicles. The design process utilizes extensive user involvement in all stages. This is critical to developing systems that have complex functions, yet are simple to maintain and operate. Described are the needs which have driven the U.S. Army towards the use of flat panels. Ultimately, the army is looking at smaller, lighter, more deployable ground combat vehicles. This goal is driving individual components to have characteristics such as low weight, low power usage, and reduced volume while maintaining ruggedness and functionality. The potential applications for flat panels in ground vehicles is also discussed. The army is looking at applications for out-the-window views (virtual periscopes), multi-functional displays, and head mounted displays to accomplish its goals of designing better crew interfaces. The army's requirements in regards to the technologies that must be developed and supported by flat panel displays are also discussed in this section. In conclusion, future projections of the use of flat panels for the Crewman's Associate ATD will be outlined. Projections will be made in terms of physical numbers and promising technologies that fulfill the goals of the CAATD and achieve the approval of the user community.

Gurd, Eric D.; Forest, Coryne A.

1996-05-01

84

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

85

Manufacturer evaluations of endograft modifications.  

PubMed

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

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

2013-03-01

86

Association between erectile dysfunction and cardiovascular risk in individuals with type-2 diabetes without overt cardiovascular disease  

PubMed Central

Background: Erectile dysfunction in type-2 diabetes may be an independent marker for coronary artery disease. Present study was undertaken to investigate whether type-2 diabetic patients with erectile dysfunction without having overt cardiovascular disease had increased cardiovascular risk. Aim: To find out correlation between ED and cardiovascular risk in diabetic patients. Methods: Fifty type-2 diabetic patients were assessed for erectile dysfunction using international index of erectile dysfunction (IIEF-5), which include questionnaire and cardiovascular risk assessment by multiparameter cardiovascular analysis device (periscope). Results: The prevalence of erectile dysfunction in type-2 diabetics was very high (78%), mild, moderate and severe ED was present in 6, 36 and 36%, respectively. The total cardiovascular risk was more in patients with ED in comparison to patients without ED (34.87 ± 18.82 vs 20.91 ± 11.03 p = 0.002). The mean 10-years coronary risk and cardiac risk was 12.00 + 9.60 and 22.23 + 14.14 (p = 0.029) and 13.36 ± 1.22 and 28.85 ± 4.13 (p 0.002) in patients without ED and with ED respectively. The mean vascular and atherosclerosis risk was 28.73 ± 13.94 and 39.38 ± 19.51 (p > 0.05) and 26.18 ± 10.31 and 33.92 ± 13.40 (p > 0.05) in patients without ED and with ED, respectively. Total cardiovascular risk was found to increase with age, duration of diabetes and HbA1c levels. Conclusion: The total cardiovascular risk increases with increasing severity of erectile dysfunction in type-2 diabetic patients without having overt cardiovascular disease.

Meena, Babu Lal; Kochar, Dhanpat Kumar; Agarwal, Tulsi Das; Choudhary, Raghvendra; Kochar, Abhishek

2009-01-01

87

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

88

A historical perspective of remote operations and robotics in nuclear facilities. Robotics and Intelligent Systems Program  

SciTech Connect

The field of remote technology is continuing to evolve to support man`s efforts to perform tasks in hostile environments. The technology which we recognize today as remote technology has evolved over the last 45 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 largely due to the unsatisfactory performance of the protective-clothing approach in many hostile applications. Manipulation systems which have been developed include crane/impact wrench systems, unilateral power manipulators, mechanical master/slaves, and servomanipulators. Viewing systems have included periscopes, shield windows, and television systems. Experience over the past 45 years indicates that maintenance system flexibility is essential to typical repair tasks because they are usually not repetitive, structured, or planned. Fully remote design (manipulation, task provisions, remote tooling, and facility synergy) is essential to work task efficiency. Work for space applications has been primarily research oriented with relatively few successful space applications, although the shuttle`s remote manipulator system has been quite successful. In the last decade, underwater applications have moved forward significantly, with the offshore oil industry and military applications providing the primary impetus.

Herndon, J.N.

1992-12-31

89

RoboLab and virtual environments  

NASA Technical Reports Server (NTRS)

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

Giarratano, Joseph C.

1994-01-01

90

Investigating the possibility of a monitoring fast ion diagnostic for ITER  

NASA Astrophysics Data System (ADS)

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

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

2008-10-01

91

Coronal Holes At Microwaves As Based On Observations With The RATAN-600 Radiotelescope  

NASA Astrophysics Data System (ADS)

The multiwavelength radio observations of the coronal holes (CH) have been carried out on the RATAN-600 radiotelescope at microwaves during the last minimum of solar activity (1995-1996). These data are compared with those obtained by the same method on RATAN-600 during the previous period of low solar activity in 1984-1985. The southern sector of the RATAN-600 radio telescope in combination with a plane periscopic mirror was used. The total intensity and circularly polarized component of the solar radio emission have been recorded daily simultaneously at 30-40 wavelengths in the range of 2-30 cm using the Panoramic Analyser of Spectra (Bogod, V.M., et al., 1992, Proceedings of IAU Colloquim N.141, p.79). The radio telescope provided resolution of 17" x 13' at 2.0 cm. We considered 9 equatorial isolated coronal holes which were observed during several solar rotations (according to He I 10830 AA data). 1. The contrasts of brightness temperature of CH against the quiet Sun in 1995-96 are turned to be lower than those in the previous cycle. But the absolute values of brightness temperature of CH and their spectra in the range of 2-30 cm are the same for two periods. 2. The coronal holes in 1995-1996 had the different dependence of their effective radio sizes on the wavelength in the range of 8-30 cm. The most coronal holes at previous activity minimum showed the increase of the radio size with wavelength increasing in the range of 8-32 cm. At the last minimum two coronal holes had the constant radio sizes in the range of 8-30 cm, and one CH showed the decrease of the radio size with wavelength increasing. The different relations between sizes of EUV, SXR and microwave images of coronal holes has been found also. 3. The coincidence of calculated and observed limb effects detected with RATAN-600 during the rise of one coronal hole (March, 1996) confirmed the validity of the empirical homogeneous models of CH and quiet Sun atmospheres constructed on the base of RATAN-600 data obtained in the previous minimum. 4. At first time the circular polarized emission associated with the isolated equatorial coronal hole (CMPs - 13.10.96, 9.11.96) has been registered in the range of 9-30 cm. The degree of polarisation was 0.2-3%. In the framework of bremsstrahlung mechanism of radio emission it means that the magnetic field strength (longitudinal component) in CH is of 2-10 G at the level of upper chromosphere - low corona (Borovik, V.N., Medar,V.G., Korzhavin A.N., 1999. Pisma v Astron.Zh.,25, N 1, 1-9, in russ.) 5. The examples of the different effects of the presence of neighbouring active regions on the radio characteristics of CH are given. 6. The small scale structures at microwaves in the quiet Sun and in coronal holes are considered. We thank the Yohkoh/SXT Team and the SOHO/EIT

Borovik, V. N.; Medar, V. G.

1999-10-01

92

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