Science.gov

Sample records for active night vision

  1. Range gated active night vision system for automobiles.

    PubMed

    David, Ofer; Kopeika, Norman S; Weizer, Boaz

    2006-10-01

    Night vision for automobiles is an emerging safety feature that is being introduced for automotive safety. We develop what we believe is an innovative new night vision system using gated imaging principles. The concept of gated imaging is described and its basic advantages, including the backscatter reduction mechanism for improved vision through fog, rain, and snow. Evaluation of performance is presented by analyzing bar pattern modulation and comparing Johnson chart predictions.

  2. Synthesized night vision goggle

    NASA Astrophysics Data System (ADS)

    Zhou, Haixian

    2000-06-01

    A Synthesized Night Vision Goggle that will be described int his paper is a new type of night vision goggle with multiple functions. It consists of three parts: main observing system, picture--superimposed system (or Cathode Ray Tube system) and Charge-Coupled Device system.

  3. Night Vision Camera

    NASA Technical Reports Server (NTRS)

    1996-01-01

    PixelVision, Inc. developed the Night Video NV652 Back-illuminated CCD Camera, based on the expertise of a former Jet Propulsion Laboratory employee and a former employee of Scientific Imaging Technologies, Inc. The camera operates without an image intensifier, using back-illuminated and thinned CCD technology to achieve extremely low light level imaging performance. The advantages of PixelVision's system over conventional cameras include greater resolution and better target identification under low light conditions, lower cost and a longer lifetime. It is used commercially for research and aviation.

  4. Advanced night vision goggles

    NASA Astrophysics Data System (ADS)

    Thacker, Clinton

    2003-02-01

    The Advanced Night Vision Goggle (ANVG) program is developing integrated wide field of view (WFOV) helmet-mounted image intensifier night vision goggle systems. ANVG will provide a FOV of approximately 40° (vertical) × 100° (horizontal) and an integrated heads-up display for overlay of flight symbology and/or FLIR imagery. The added FLIR complements the I2 imagery in out of the window or ground applications. ANVG will significantly improve safety, situational awareness, and mission capabilities in differing environments. ANVG achieves the ultra wide FOV using four image intensifier tubes in a head-mounted configuration. Additional features include a miniature flat panel display and a lightweight uncooled FLIR. The integrated design will demonstrate the capability of helmet-mounted I2 and FLIR image fusion. Fusion will be accomplished optically and will offer significant opportunities for ground applications. This paper summarizes the basic technologies, lessons learned, and program status.

  5. Vision - night blindness

    MedlinePlus

    ... People with night blindness often have trouble seeing stars on a clear night or walking through a ... certain drugs Vitamin A deficiency (rare) Nontreatable causes: Birth defects Retinitis pigmentosa

  6. Night vision device technology development

    SciTech Connect

    Funsten, H.; Nordholt, J.; Suszcynsky, D.

    1996-09-01

    This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project sought to develop microchannel plate (MCP) technologies for enhancement of night vision device (NVD) capabilities. First, segmented microchannel plates with independent gain control to minimize loss of low level light images in the presence of a bright light source (e.g., battlefield lasers, flares, and headlights) need to be developed. This enables, for example, enhanced vision capabilities during night operations in, for example, a city environment and continuous capability of aviators to see the horizon, nearground obstructions, and ground targets. Furthermore, curved microchannel plate technology to increase the field of view of NVDs while minimizing optical aberrations needs to be developed and applied. This development would significantly enhance peripheral vision capabilities of aviators and result in easier adaptation of the human eye to NVDs.

  7. Improved night vision demonstrator program status

    NASA Astrophysics Data System (ADS)

    Haran, Terence L.; James, J. Christopher; Roberts, David W.; Knotts, Michael E.; Wasilewski, Anthony A.; West, Leanne L.; Robinson, William G.; Bennett, Gisele

    2007-04-01

    Although existing night vision equipment provides a significant improvement in target detection in low light conditions, there are several limitations that limit their effectiveness. Focus is a significant problem for night vision equipment due to the low f-number optics required to obtain sufficient sensitivity as well as the dynamic nature of night vision applications, which requires frequent focus adjustments. The Georgia Tech Research Institute has developed a prototype next-generation night vision device called the Improved Night Vision Demonstrator (INVD) in order to address these shortfalls. This paper will describe the design of the INVD system as well as an analysis of its performance.

  8. Solid state active/passive night vision imager using continuous-wave laser diodes and silicon focal plane arrays

    NASA Astrophysics Data System (ADS)

    Vollmerhausen, Richard H.

    2013-04-01

    Passive imaging offers covertness and low power, while active imaging provides longer range target acquisition without the need for natural or external illumination. This paper describes a focal plane array (FPA) concept that has the low noise needed for state-of-the-art passive imaging and the high-speed gating needed for active imaging. The FPA is used with highly efficient but low-peak-power laser diodes to create a night vision imager that has the size, weight, and power attributes suitable for man-portable applications. Video output is provided in both the active and passive modes. In addition, the active mode is Class 1 eye safe and is not visible to the naked eye or to night vision goggles.

  9. Enhanced Night Vision Goggle Customer Test

    DTIC Science & Technology

    2006-08-01

    Enhanced Night Vision Goggle Customer Test by Christian B. Carstens, Charles C. Bonnett, and Elizabeth S. Redden ARL-TR-3839 August...Ground, MD 21005-5425 ARL-TR-3839 August 2006 Enhanced Night Vision Goggle Customer Test Christian B. Carstens, Charles C. Bonnett...NUMBER 4. TITLE AND SUBTITLE Enhanced Night Vision Goggle Customer Test 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 62716AH70 5e

  10. Night vision: changing the way we drive

    NASA Astrophysics Data System (ADS)

    Klapper, Stuart H.; Kyle, Robert J. S.; Nicklin, Robert L.; Kormos, Alexander L.

    2001-03-01

    A revolutionary new Night Vision System has been designed to help drivers see well beyond their headlights. From luxury automobiles to heavy trucks, Night Vision is helping drivers see better, see further, and react sooner. This paper describes how Night Vision Systems are being used in transportation and their viability for the future. It describes recent improvements to the system currently in the second year of production. It also addresses consumer education and awareness, cost reduction, product reliability, market expansion and future improvements.

  11. Analysis of the development and the prospects about vehicular infrared night vision system

    NASA Astrophysics Data System (ADS)

    Li, Jing; Fan, Hua-ping; Xie, Zu-yun; Zhou, Xiao-hong; Yu, Hong-qiang; Huang, Hui

    2013-08-01

    Through the classification of vehicular infrared night vision system and comparing the mainstream vehicle infrared night vision products, we summarized the functions of vehicular infrared night vision system which conclude night vision, defogging , strong-light resistance and biological recognition. At the same time , the vehicular infrared night vision system's markets of senior car and fire protection industry were analyzed。Finally, the conclusion was given that vehicle infrared night vision system would be used as a safety essential active safety equipment to promote the night vision photoelectric industry and automobile industry.

  12. Handling qualities comparison of panoramic night vision goggles and 46-deg. night vision goggles

    NASA Astrophysics Data System (ADS)

    Craig, Gregory; Jennings, Sion; Thorndycraft, David

    2003-09-01

    Night Vision Goggles allow the user to see in extremely low illumination levels but the visual information provided by Night Vision Goggles has a limited field-of-view that diminishes handling-qualities in the night flying environment. Panoramic Night Vision Goggles were designed to correct this problem by providing a 100° horizontal field-of-view which is larger than currently used Night Vision Goggles. However, in the first generation Panoramic Night Vision Goggle, the improved field of view came at the cost of diminished resolution, contrast and central overlap area when compared to conventional Night Vision Goggles. This paper describes an evaluation that was conducted in the variable stability NRC Bell-205 helicopter to examine the influence on system handling qualities of the Panoramic Night Vision Goggles and a 46° field-of-view UK Night Vision Goggle. Five pilots flew the ADS-33D hover, sidestep and pirouette manoeuvres in simulated night conditions with the UK Night Vision Goggle and the Panoramic Night Vision Goggle. Both subjective and objective measures of task performance were obtained. Handling-qualities ratings showed the pirouette was performed better with the Panoramic Night Vision Goggles. This was the only manoeuvre where there was a clear-cut handling qualities improvement when using the Panoramic Night Vision Goggles. Other manoeuvres such as the sidestep and hover did not show definitive handling qualities rating differences between the two Night Vision Goggle types. The flight test results were interpreted in terms of the design trade-offs of the two night vision systems, with regard to the different acuity, binocular overlaps and fields-of-view.

  13. Civilian use of night vision goggles.

    PubMed

    Salazar, Guillermo; Temme, Leonard; Antonio, J Charles

    2003-01-01

    Civil aviation operators have expressed an increased interest in conducting night operations with night vision imaging systems. The development of special operational concepts, hardware requirements, training requirements, and regulatory change and oversight is necessary to control for the known performance constraints associated with these devices. In 2001, the Aerospace Medical Association initiated an internal request to review the human factors issues concerning the use of night vision goggles (NVGs) in civilian flight operations. This paper provides some basic information on night vision imaging systems to highlight the Association's position for supporting the appropriate use of NVGs in civilian aviation while concurrently expressing the need for a judicious and studied approach to their deployment.

  14. Vernier acuity through night vision goggles.

    PubMed

    Rabin, J

    1993-08-01

    Night vision goggles (NVG's) are being used increasingly in military and civilian environments. Despite the use of these devices, relatively few tests exist to assess visual performance through NVG's. Hyperacuity tasks may provide a sensitive index of performance through night vision devices. In this study, grating vernier acuity was measured through NVG's. As reported previously, a power law relation was observed between vernier acuity and stimulus contrast. Comparison of vernier acuity with and without NVG's indicated that performance is limited by the contrast transfer of the device. Vernier acuity measurements can be used to assess the quality of vision and quantity of contrast transferred through night vision devices.

  15. Multi-channel automotive night vision system

    NASA Astrophysics Data System (ADS)

    Lu, Gang; Wang, Li-jun; Zhang, Yi

    2013-09-01

    A four-channel automotive night vision system is designed and developed .It is consist of the four active near-infrared cameras and an Mulit-channel image processing display unit,cameras were placed in the automobile front, left, right and rear of the system .The system uses near-infrared laser light source,the laser light beam is collimated, the light source contains a thermoelectric cooler (TEC),It can be synchronized with the camera focusing, also has an automatic light intensity adjustment, and thus can ensure the image quality. The principle of composition of the system is description in detail,on this basis, beam collimation,the LD driving and LD temperature control of near-infrared laser light source,four-channel image processing display are discussed.The system can be used in driver assistance, car BLIS, car parking assist system and car alarm system in day and night.

  16. Evaluation of Two Night-Vision Devices.

    ERIC Educational Resources Information Center

    Robinson, J.; And Others

    1990-01-01

    Twelve legally blind men tested two night-vision devices: one wide-angle light and one with a high-intensity beam. The study concluded that no one night light is best for all individuals and in some cases a smaller angle, high-intensity light may be more useful than a wider angle one. (Author/JDD)

  17. Night Vision Manual for the Flight Surgeon

    DTIC Science & Technology

    1992-08-01

    may cause night blindness are glaucoma, progressive cone/rod dystrophies (e.g., retinitis pigmentosa , Stargardt’s disease), drug toxicity (e.g...Alabama, July 1989. 38. Berson EL, Rabin AR, Mehaffey L. Advances in night vision twchnology: A pocketscope for patients with retinitis pigmentosa ... retinal sensitivity to dim light. Regeneration of the photopigments occurs during dark adaptation. The fully dark-adapted eye, in which photopigment

  18. Cockpit Readiness For Night Vision Goggles

    NASA Astrophysics Data System (ADS)

    Scholl, Marija S.; Scholl, James W.

    1987-09-01

    The introduction of night vision goggles into the cockpit environment may produce incompatibility with existing cockpit optoelectronic instrumentation. The methodology used to identify the origin of the spurious signal is demonstrated with the example of an electronic display. The amount of radiation emitted by a gray body in the wavelength region of goggle sensitivity is calculated. A simple procedure for preflight testing of cockpit instrumentation using a commercially available infrared camera is recommended. Other recommendations include the specification of cockpit instrumentation for compatibility with night vision devices.

  19. Cockpit readiness for night vision goggles

    NASA Technical Reports Server (NTRS)

    Scholl, Marija S.; Scholl, James W.

    1987-01-01

    The introduction of night vision goggles into the cockpit environment may produce incompatibility with existing cockpit optoelectronic instrumentation. The methodology used to identify the origin of the spurious signal is demonstrated with the example of an electronic display. The amount of radiation emitted by a gray body in the wavelength region of goggle sensitivity is calculated. A simple procedure for preflight testing of cockpit instrumentation using a commercially available infrared camera is recommended. Other recommendations include the specification of cocklpit instrumentation for compatibility with night vision devices.

  20. Night vision by cuttlefish enables changeable camouflage.

    PubMed

    Allen, Justine J; Mäthger, Lydia M; Buresch, Kendra C; Fetchko, Thomas; Gardner, Meg; Hanlon, Roger T

    2010-12-01

    Because visual predation occurs day and night, many predators must have good night vision. Prey therefore exhibit antipredator behaviours in very dim light. In the field, the giant Australian cuttlefish (Sepia apama) assumes camouflaged body patterns at night, each tailored to its immediate environment. However, the question of whether cuttlefish have the perceptual capability to change their camouflage at night (as they do in day) has not been addressed. In this study, we: (1) monitored the camouflage patterns of Sepia officinalis during the transition from daytime to night-time using a natural daylight cycle and (2) tested whether cuttlefish on a particular artificial substrate change their camouflage body patterns when the substrate is changed under dim light (down to starlight, 0.003 lux) in a controlled light field in a dark room setting. We found that cuttlefish camouflage patterns are indeed adaptable at night: animals responded to a change in their visual environment with the appropriate body pattern change. Whether to deceive their prey or predators, cuttlefish use their excellent night vision to perform adaptive camouflage in dim light.

  1. Night Vision Goggles Objectives Lens Focusing Methodology

    DTIC Science & Technology

    2000-01-01

    a different methodology . The second study was prompted by the inconclusiveness of the first study. METHOD - STUDY ONE Observers The trained observers......3. DATES COVERED - 4. TITLE AND SUBTITLE Night Vision Goggles Objectives Lens Focusing Methodology 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  2. [Evaluation of condition and factors affecting activity effectiveness and visual performance of pilots who use night vision goggles during the helicopter flights].

    PubMed

    Aleksandrov, A S; Davydov, V V; Lapa, V V; Minakov, A A; Sukhanov, V V; Chistov, S D

    2014-07-01

    According to analysis of questionnaire authors revealed factors, which affect activity effectiveness, and visual performance of pilots who use night vision goggles during the helicopter flights. These are: difficulty of flight tasks, flying conditions, illusion of attitude. Authors gave possible ways to reduce an impact of these factors.

  3. HMD digital night vision system for fixed wing fighters

    NASA Astrophysics Data System (ADS)

    Foote, Bobby D.

    2013-05-01

    Digital night sensor technology offers both advantages and disadvantages over standard analog systems. As the digital night sensor technology matures and disadvantages are overcome, the transition away from analog type sensors will increase with new programs. In response to this growing need RCEVS is actively investing in digital night vision systems that will provide the performance needed for the future. Rockwell Collins and Elbit Systems of America continue to invest in digital night technology and have completed laboratory, ground and preliminary flight testing to evaluate the important key factors for night vision. These evaluations have led to a summary of the maturity of the digital night capability and status of the key performance gap between analog and digital systems. Introduction of Digital Night Vision Systems can be found in the roadmap of future fixed wing and rotorcraft programs beginning in 2015. This will bring a new set of capabilities to the pilot that will enhance his abilities to perform night operations with no loss of performance.

  4. Visual evoked potentials through night vision goggles.

    PubMed

    Rabin, J

    1994-04-01

    Night vision goggles (NVG's) have widespread use in military and civilian environments. NVG's amplify ambient illumination making performance possible when there is insufficient illumination for normal vision. While visual performance through NVG's is commonly assessed by measuring threshold functions such as visual acuity, few attempts have been made to assess vision through NVG's at suprathreshold levels of stimulation. Such information would be useful to better understand vision through NVG's across a range of stimulus conditions. In this study visual evoked potentials (VEP's) were used to evaluate vision through NVG's across a range of stimulus contrasts. The amplitude and latency of the VEP varied linearly with log contrast. A comparison of VEP's recorded with and without NVG's was used to estimate contrast attenuation through the device. VEP's offer an objective, electrophysiological tool to assess visual performance through NVG's at both threshold and suprathreshold levels of visual stimulation.

  5. Night Mobility Instruction for Child with Low Vision.

    ERIC Educational Resources Information Center

    Tapp, Kenneth L.

    1985-01-01

    The challenges of after-dark travel for low vision children are examined in terms of physical effects of low light on normal and abnormal vision and consequences for low vision travel and orientation skills. Techniques for efficient vision use are suggested along with night travel aids and considerations in night driver vision. (CL)

  6. Insect photoreceptor adaptations to night vision.

    PubMed

    Honkanen, Anna; Immonen, Esa-Ville; Salmela, Iikka; Heimonen, Kyösti; Weckström, Matti

    2017-04-05

    Night vision is ultimately about extracting information from a noisy visual input. Several species of nocturnal insects exhibit complex visually guided behaviour in conditions where most animals are practically blind. The compound eyes of nocturnal insects produce strong responses to single photons and process them into meaningful neural signals, which are amplified by specialized neuroanatomical structures. While a lot is known about the light responses and the anatomical structures that promote pooling of responses to increase sensitivity, there is still a dearth of knowledge on the physiology of night vision. Retinal photoreceptors form the first bottleneck for the transfer of visual information. In this review, we cover the basics of what is known about physiological adaptations of insect photoreceptors for low-light vision. We will also discuss major enigmas of some of the functional properties of nocturnal photoreceptors, and describe recent advances in methodologies that may help to solve them and broaden the field of insect vision research to new model animals.This article is part of the themed issue 'Vision in dim light'.

  7. Statistical assessment of night vision goggle noise

    NASA Astrophysics Data System (ADS)

    Wales, Jesse G.; Marasco, Peter L.

    2006-05-01

    New advancements in charged-coupled device (CCD) technology allow for further investigation into the spatial nature of night vision goggle (NVG) noise distributions. This is significant because it is common practice in new NVG technology to combine image intensifiers with CCDs for night vision imaging. In this study, images of NVG noise are recorded by a CCD camera while varying input radiance and using multiple goggle types. Noise distributions characterized using histograms of these images are analyzed and fitted with curves. Using the changes in the distribution and relating distribution changes (coefficient changes) to input radiance and goggle performance provides a very accurate noise characterization. This study finds that a Weibull distribution seems more appropriate than a Poisson distribution, producing higher correlation coefficient fits. In addition, the paper suggests possible ways the noise models developed here can impact advancements in NVG image enhancement using this new technology.

  8. The design of CY-1R night vision helmet

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Chang, Benkang

    2004-05-01

    In this paper, the research intention and design principle of CY-1R night vision helmet are explained which fills the gaps in active-passive combined night vision field in our country. The structure, composition, mechanism and overall performance of the goggle are analyzed. It is a new type device consisting of laser illuminator system, special optical system and high performance low-level-light intensifier. Based on these characteristics, the sensitivity of the system is high and the image observed is very clear. Taking advantage of it, we can complete the military operation under any atrocious weather conditions.

  9. Night Vision Manual for the Flight Surgeon.

    DTIC Science & Technology

    1985-08-01

    by optic nerve and pathways to Brodmann’s occipital areas 17 and 18). Perception occurs - vision Sensitive material ( retinal pigment) must be...clearly may be defined as glare. Glare becomes a problem in patients with opacities of the ocular media or with retinal diseases. 3 FME tN [I.I Sl IN FM...reduction of pupillary area caused by the drug. 3. Retinal causes of abnormal dark adaptation. a. Congenital stationary night blindness. b. etinitis

  10. Design Considerations For Night Vision Goggles

    NASA Astrophysics Data System (ADS)

    Glasheen, W. M.; Reiss, R. S.

    1985-01-01

    Baird Corporation of Bedford, Massachusetts, has designed and developed two similar night vision goggles. These goggles are binocular viewing to the wearer's eyes, but use a single objective lens and a single image intensifier tube. Binocular viewing is achieved by dividing a single image and sharing it between the'viewer's eyes. The goggles are self-sufficient, independent instruments which can be simply and easily interfaced with a face mask that the viewer wears. This paper covers the main design considerations that are associated with achieving the goals of these goggle configurations and their performance. Baird's first goggle design is designated the GP/NVG; the second is designated the AN/PVS-7. The GP/NVG night vision goggle is a high-performance, single intensifier tube, passive night vision device that provides the user with a 40-degree field of view at unity magnification. The fixed aperture, f/1.0 objective lens collects the available light and images it on the fiber optic faceplate of the second generation image intensifier tube. The image intensifier tube converts the real image at the fiber optic faceplate into electrons across the image, amplifies them, and then reconverts the electrons into a real, visible image at the fiber optic output of the tube. This image is then collimated to appear as if it is coming from infinity, split in two, and reimaged by the relay lenses. The eyelenses provide a magnified image to the user. The user can adjust each eyelens to clearly view the output faceplate of the image intensifier tube. This adjustment is made only once for each user. The objective focus can be manually set for distances from 25 centimeters to infinity. The general configuration of this night vision goggle is similar to that of a pair of single objective binocular field glasses. It is extremely lightweight (with most of the main construction molded from plastic) and compact for easy handling. All adjustments and on/off switching have been "human

  11. Flicker detection through night vision goggles.

    PubMed

    Rabin, J

    1994-02-01

    Visual performance through night vision goggles (NVG's) is commonly assessed with letter charts or other static displays. Few attempts have been made to evaluate dynamic aspects of vision through NVG's. Such information may be used to better predict human performance and guide the development of improved devices. In this study, contrast thresholds for detection of flickering targets were measured through NVG's across a range of ambient conditions. A comparison of measurements with and without NVG's indicated that flicker detection is limited by the contrast and luminance of the NVG display. The contrast limitation is largely independent of stimulus flicker frequency. Increasing the transfer of static contrast and/or luminance through NVG's will also improve dynamic visual performance.

  12. Panoramic night vision goggle flight test results

    NASA Astrophysics Data System (ADS)

    Franck, Douglas L.; Geiselman, Eric E.; Craig, Jeffrey L.

    2000-06-01

    The Panoramic Night Vision Goggle (PNVG) has begun operational test and evaluation with its 100-degree horizontal by 40-degree vertical field of view (FOV) on different aircraft and at different locations. Two configurations of the PNVG are being evaluated. The first configuration design (PNVG I) is very low in profile and fits underneath a visor. PNVG I can be retained by the pilot during ejection. This configuration is interchangeable with a day helmet mounted tracker and display through a standard universal connector. The second configuration (PNVG II) resembles the currently fielded 40-degree circular FOV Aviator Night Vision Imaging Systems (ANVIS) and is designed for non-ejection seat aircraft and ground applications. Pilots completed subjective questionnaires after each flight to compare the capability of the 100-degree horizontal by 40-degree vertical PNVG to the 40-degree circular ANVIS across different operational tasks. This paper discusses current findings and pilot feedback from the flight trials objectives of the next phase of the PNVG program are also discussed.

  13. New night vision goggle gain definition

    NASA Astrophysics Data System (ADS)

    Podobedov, Vyacheslav B.; Eppeldauer, George P.; Larason, Thomas C.

    2015-05-01

    A new definition is proposed for the calibration of Night Vision Goggle (NVG) gains. This definition is based on the measurement of radiometric input and output quantities of the NVG. While the old definition used the "equivalent fL" which is a non SI traceable luminance unit, the new definition utilizes the radiance quantities that are traceable to the SI units through NIST standards. The new NVG gain matches the previous one as a result of the application of a correction coefficient originating from the conversion of the radiance to luminance units. The new definition was tested at the NIST Night Vision Calibration Facility and the measurement results were compared to the data obtained with a Hoffman Test Set Model ANV-126. Comparing the radiometric quantities of the Hoffman Test Set and those measured by the NIST transfer standard radiometer, indicates that the observed differences up to 15% were due to the calibration and experimental errors of the ANV-126 Test Set. In view of different spectral characteristics of luminophores that can be utilized in the NVG design, the simulation of the NVG output for gain measurement was performed. The NVG output was simulated with a sphere-based source using different LEDs and the measured gain was compared to that obtained with the ANV-126 internal luminance meter. The NVG gain uncertainty analysis was performed for the Type A, B, and C goggles.

  14. [Optimizing visual work of pilot wearing night vision glasses].

    PubMed

    Davydov, V V; Golosov, S Iu; Ivanov, A I; Lapa, V V; Riabinin, V A

    2011-01-01

    The article deals with results of experimental studies on optimizing visual work conditions of pilot in night vision glasses. Prevention of visual fatigue during work in night vision glasses was proved to be contributed mostly by the image brightness (in range of 0.7-1.8 candle/m2) adjustable by the pilot, precise individual settings of optic system in night vision glasses (by viewer's eye base) and regulation of the work duration.

  15. The impact of changing night vision goggle spectral response on night vision imaging system lighting compatibility

    NASA Astrophysics Data System (ADS)

    Task, Harry L.; Marasco, Peter L.

    2004-09-01

    The defining document outlining night-vision imaging system (NVIS) compatible lighting, MIL-L-85762A, was written in the mid 1980's, based on what was then the state of the art in night vision and image intensification. Since that time there have been changes in the photocathode sensitivity and the minus-blue coatings applied to the objective lenses. Specifically, many aviation night-vision goggles (NVGs) in the Air Force are equipped with so-called "leaky green" or Class C type objective lens coatings that provide a small amount of transmission around 545 nanometers so that the displays that use a P-43 phosphor can be seen through the NVGs. However, current NVIS compatibility requirements documents have not been updated to include these changes. Documents that followed and replaced MIL-L-85762A (ASC/ENFC-96-01 and MIL-STD-3009) addressed aspects of then current NVIS technology, but did little to change the actual content or NVIS radiance requirements set forth in the original MIL-L-85762A. This paper examines the impact of spectral response changes, introduced by changes in image tube parameters and objective lens minus-blue filters, on NVIS compatibility and NVIS radiance calculations. Possible impact on NVIS lighting requirements is also discussed. In addition, arguments are presented for revisiting NVIS radiometric unit conventions.

  16. Human factors issues in the use of night vision devices

    NASA Technical Reports Server (NTRS)

    Kaiser, Mary K.; Foyle, David C.

    1991-01-01

    An account is given of the critical human factors that arise in field data on the differences between night vision displays and unaided day vision. Attention is given to the findings of empirical studies of performance on rotorcraft-flight-relevant perceptual tasks in which depth and distance perception are critical factors. Suggestions are made for man-machine-critical component design modifications in current night vision systems.

  17. Spatial navigation using night vision goggles

    NASA Astrophysics Data System (ADS)

    Gauthier, Michelle; Parush, Avi; Macuda, Todd; Tang, Denis; Craig, Greg; Jennings, Sion

    2006-05-01

    While anecdotal reports suggest that Night Vision Goggles influence spatial navigation and wayfinding (Braithwaite, Douglass, Durnford, and Lucas, 1998), few studies have systematically characterized the nature of these effects. To address this issue, the current study examined the impact of NVGs on navigation and wayfinding performance. One group of participants were required to navigate a walking maze and retrieve target objects while wearing NVGs (experimental condition), while a second control group navigated the maze without NVGs. We measured several performance metrics of navigation and wayfinding. Our results show that navigation and wayfinding with NVGs (experimental group) appeared to be harder, with longer navigation durations and more navigational errors compared to not using NVGs (control group). However, a significant decrease in navigation duration over the course of the wayfinding trials occurred earlier with NVGs, in addition to significant decreases in navigational steps compared to the control group. These results support the notion that NVGs directly affect spatial navigation and wayfinding performance. These degradations in performance should be considered in operational planning and NVG training programs. Further research is necessary to expand our understanding of the impact of NVGs on spatial cognition.

  18. Night vision imaging system lighting evaluation methodology

    NASA Astrophysics Data System (ADS)

    Task, H. Lee; Pinkus, Alan R.; Barbato, Maryann H.; Hausmann, Martha A.

    2005-05-01

    In order for night vision goggles (NVGs) to be effective in aircraft operations, it is necessary for the cockpit lighting and displays to be NVG compatible. It has been assumed that the cockpit lighting is compatible with NVGs if the radiance values are compliant with the limits listed in Mil-L-85762A and Mil-Std-3009. However, these documents also describe a NVG-lighting compatibility field test procedure that is based on visual acuity. The objective of the study described in this paper was to determine how reliable and precise the visual acuity-based (VAB) field evaluation method is and compare it to a VAB method that employs less expensive equipment. In addition, an alternative, objective method of evaluating compatibility of the cockpit lighting was investigated. An inexpensive cockpit lighting simulator was devised to investigate two different interference conditions and six different radiance levels per condition. This paper describes the results, which indicate the objective method, based on light output of the NVGs, is more precise and reliable than the visual acuity-based method. Precision and reliability were assessed based on a probability of rejection (of the lighting system) function approach that was developed specifically for this study.

  19. Psychophysical measurement of night vision goggle noise

    NASA Astrophysics Data System (ADS)

    Glasgow, Rachael L.; Marasco, Peter L.; Havig, Paul R.; Martinsen, Gary L.; Reis, George A.; Heft, Eric L.

    2003-09-01

    Pilots, developers, and other users of night-vision goggles (NVGs) have pointed out that different NVG image intensifier tubes have different subjective noise characteristics. Currently, no good model of the visual impact of NVG noise exists. Because it is very difficult to objectively measure the noise of a NVG, a method for assessing noise subjectively using simple psychophysical procedures was developed. This paper discusses the use of a computer program to generate noise images similar to what an observer sees through an NVG, based on filtered white noise. The images generated were based on 1/f (where f is frequency) filtered white noise with several adjustable parameters. Adjusting each of these parameters varied different characteristics of the noise. This paper discusses a study where observers compared the computer-generated noise images to true NVG noise and were asked to determine which computer-generated image was the best representation of the true noise. This method was repeated with different types of NVGs and at different luminance levels to study what NVG parameters cause variations in NVG noise.

  20. Visual anomalies and display night vision goggles

    NASA Astrophysics Data System (ADS)

    Jarrett, Donald N.; Ineson, Judith; Cheetham, Mark

    2003-09-01

    A brief study has been conducted to investigate several visual anomalies reported by test pilots using a Display Night Vision Goggle (DNVG) that superimposed symbols onto the intensified image seen by the right eye. A survey of relevant research suggests that one oddity, an apparent focus mis-match between the scene image and the injected symbols, is an irremovable facet of the perception of bright, contrasting, overlaid symbols. A second oddity, an uncomfortable and distracting blurring of the under-stimulated left eye during periods of flight in cloud, was eventually experienced by several people in a laboratory simulation, the effect being more noticeable if the under-stimulated eye was the dominant eye. A subsequent apparent enlargement of the HUD symbols and a post-flight focussing delay by the left eye seemed to be after-effects of whatever caused the ocular discomfort. As about 30% of the population are left eye dominant, the disturbing discomfort and aftermath could affect this proportion of pilots using a right-eye DNVG. Although further work is needed to understand the phenomena, it would be wise to warn aircrew and enable the symbol injection unit to be fitted to either channel of the DNVG.

  1. Hands-free focus night vision technology demonstration

    NASA Astrophysics Data System (ADS)

    Haran, Terence L.; James, J. Christopher; Roberts, David W.; Knotts, Michael E.; Wasilewski, Anthony A.; West, Leanne L.; Robinson, William G.; Bennett, Gisele

    2007-04-01

    The Georgia Tech Research Institute is currently developing a device to demonstrate a hands-free focus technology for head-mounted night vision sensors. The demonstrator device will integrate a computational imaging technique that increases depth of field with a digital night vision sensor. The goal of the demonstrator is to serve as a test bed for evaluating the critical performance/operational parameters necessary for the hands-free focus technology to support future tactical night vision concepts of operation. This paper will provide an overview of the technology studies and design analyses that have been performed to date as well as the current state of the demonstrator design.

  2. Liquid crystal modulated optical amplifier for night vision imaging

    NASA Astrophysics Data System (ADS)

    Parfenov, Alexander; Xia, X. Winston; Tengara, Indra; Win, Tin; Holmstedt, Jason; Rakuljic, Neven; Aye, Tin M.; Swinney, Mathew W.; Marasco, Peter L.

    2008-08-01

    Image intensifier tubes, as part of night vision devices, have been the primary devices for the detection and amplification of near infrared light for night vision operations. In this paper, we demonstrate a novel all-optical night vision amplifier device with a potential to replace the image intensifier tube in night vision goggles. This image amplifier is based on a novel structure of semiconductor and spectrally tunable liquid crystal (LC) materials within a thin cell. The LC reacts to near-infrared (NIR) radiation but is unaffected by visible light, allowing see-through capability including visible-wavelength cockpit light. The technology is made very attractive by its high sensitivity, spatial resolution, and contrast without expensive, bulky, and heavy optics or high-voltage components.

  3. Night Vision Goggles in Emergency Medical Service (EMS) Helicopters

    DTIC Science & Technology

    1994-07-01

    corrected with certain types of bifocal spectacles that compensate for the inadequate accommodative power of the eye lenses . Niqht Myopia. Myopic...5 1.1. 6 Dark Adaptation ..................... ............. 7 1.1.7 Night Vision Protection ...night flight. Special corrective lenses can be prescribed to correct for myopia. Astiqmatism. Astigmatism is an irregularity of the shape of the cornea

  4. The research on projective visual system of night vision goggles

    NASA Astrophysics Data System (ADS)

    Zhao, Shun-long

    2009-07-01

    Driven by the need for lightweight night vision goggles with good performance, we apply the projective lens into night vision goggles to act as visual system. A 40-deg FOV projection lens is provided. The useful diameter of the image intensifier is 16mm, and the Resolutions at Center and edge are both 60-lp/mm. The projection lens has a 28mm diameter and 20g weight. The maximum distortion of the system is less than 0.15%. The MTF maintained more than 0.6 at a 60-lp/mm resolution across the FOV. So the lens meets the requirements of the visual system. Besides, two types of projective visual system of night vision goggles are presented: the Direct-view projective visual system and the Seethrough projective visual system. And the See-through projective visual system enables us to observe the object with our eyes directly, without other action, when the environment becomes bright in a sudden. Finally we have reached a conclusion: The projective system has advantages over traditional eyepiece in night vision goggles. It is very useful to minish the volume, lighten the neck supports, and improve the imaging quality. It provides a new idea and concept for visual system design in night vision goggles.

  5. Helicopter Night Vision System Simulation Evaluation

    DTIC Science & Technology

    1981-12-01

    mision safety. The enroute evaluation indicates a con- sistent preference for the 4HMD-PMD configuration. The copilot felt that the virtual HUD...pilot but never allowed Cho copilot to slow in a hover. In edsencer the night cranpore mision appears wo be a two pilot task with a t consant verbal

  6. Evaluation of visual acuity with Gen 3 night vision goggles

    NASA Technical Reports Server (NTRS)

    Bradley, Arthur; Kaiser, Mary K.

    1994-01-01

    Using laboratory simulations, visual performance was measured at luminance and night vision imaging system (NVIS) radiance levels typically encountered in the natural nocturnal environment. Comparisons were made between visual performance with unaided vision and that observed with subjects using image intensification. An Amplified Night Vision Imaging System (ANVIS6) binocular image intensifier was used. Light levels available in the experiments (using video display technology and filters) were matched to those of reflecting objects illuminated by representative night-sky conditions (e.g., full moon, starlight). Results show that as expected, the precipitous decline in foveal acuity experienced with decreasing mesopic luminance levels is effectively shifted to much lower light levels by use of an image intensification system. The benefits of intensification are most pronounced foveally, but still observable at 20 deg eccentricity. Binocularity provides a small improvement in visual acuity under both intensified and unintensified conditions.

  7. Moulded infrared optics making night vision for cars within reach

    NASA Astrophysics Data System (ADS)

    Bourget, Antoine; Guimond, Yann; Franks, John; Van Den Bergh, Marleen

    2005-02-01

    Sustainable mobility is a major public concern, making increased safety one of the major challenges for the car of the future. About half of all serious traffic accidents occur at night, while only a minority of journeys is at night. Reduced visibility is one of the main reasons for these striking statistics and this explains the interest of the automobile industry in Enhanced Night Vision Systems. As an answer to the need for high volume, low cost optics for these applications, Umicore has developed GASIR. This material is transparent in the NEAR and FAR infrared, and is mouldable into high quality finished spherical, aspherical and diffractive lenses. Umicore's GASIR moulded lenses are an ideal solution for thermal imaging for cars (Night Vision) and for sensing systems like pedestrian detection, collision avoidance, occupation detection, intelligent airbag systems etc.

  8. Night vision goggles resolution performance at low contrast levels

    NASA Astrophysics Data System (ADS)

    Tjernstrom, Lars

    1993-01-01

    NVG (Night Vision Goggle) resolution performance data is usually given as measured against high contrast, black and white, targets. When NVGs are used as night vision aids for visual night flight, the scene viewed by the pilot is in most cases dominated by low contrast. Therefore, NVG performance at low contrast levels is more relevant to the piloting task than NVG resolution at high contrast levels. A set of resolution targets with different contrast levels was designed and ground tests performed at various light levels outdoors at night. The results showed a marked loss of resolution at lower contrast levels. The presentation will describe the test method, give the results and discuss how the results may be explained. A method for using the test results as the basis for correlating piloting performance to light levels will be presented.

  9. Effects of Extended Hypoxia on Night Vision

    DTIC Science & Technology

    1983-06-01

    and Krill (5) have reported a study of fundamental sig- nificance on the effects of stimulus paraneter; and retinal placement of the stimulus on night...by Ernest and Krill (5), that the early segment of the dark adaptation function was unaffected by hypoxia. This disagreement probably can be explained...in recovery capability, even after extended hypoxia. The clear implication of this relationship for practical operetions is that supplemental oxygen

  10. Passive Night Vision Sensor Comparison for Unmanned Ground Vehicle Stereo Vision Navigation

    NASA Technical Reports Server (NTRS)

    Owens, Ken; Matthies, Larry

    2000-01-01

    One goal of the "Demo III" unmanned ground vehicle program is to enable autonomous nighttime navigation at speeds of up to 10 m.p.h. To perform obstacle detection at night with stereo vision will require night vision cameras that produce adequate image quality for the driving speeds, vehicle dynamics, obstacle sizes, and scene conditions that will be encountered. This paper analyzes the suitability of four classes of night vision cameras (3-5 micrometer cooled FLIR, 8-12 micrometer cooled FLIR, 8-12 micrometer uncooled FLIR, and image intensifiers) for night stereo vision, using criteria based on stereo matching quality, image signal to noise ratio, motion blur and synchronization capability. We find that only cooled FLIRs will enable stereo vision performance that meets the goals of the Demo III program for nighttime autonomous mobility.

  11. Low light comparison of target visibility with night vision goggles

    NASA Astrophysics Data System (ADS)

    Craig, Gregory; Brulotte, Michel; Carignan, Stephan; Macuda, Todd; Jennings, Sion

    2008-04-01

    Different night vision goggle image intensification technologies were tested to compare goggle performance in low light conditions. A total of four different night vision goggles were tested in a laboratory dark room. The laboratory tests consisted of viewing Landolt acuity stimuli of different contrast levels with each set of goggles and without the goggles in full light conditions (baseline performance). The results from the laboratory testing indicated that there were significant differences in acuity between the NVGs, particularly for low contrast targets. These data suggest that NVG standards developed using high contrast targets, even in low light conditions may not provide the full story of how the NVG will perform in flight.

  12. Helicopter flights with night-vision goggles: Human factors aspects

    NASA Technical Reports Server (NTRS)

    Brickner, Michael S.

    1989-01-01

    Night-vision goggles (NVGs) and, in particular, the advanced, helmet-mounted Aviators Night-Vision-Imaging System (ANVIS) allows helicopter pilots to perform low-level flight at night. It consists of light intensifier tubes which amplify low-intensity ambient illumination (star and moon light) and an optical system which together produce a bright image of the scene. However, these NVGs do not turn night into day, and, while they may often provide significant advantages over unaided night flight, they may also result in visual fatigue, high workload, and safety hazards. These problems reflect both system limitations and human-factors issues. A brief description of the technical characteristics of NVGs and of human night-vision capabilities is followed by a description and analysis of specific perceptual problems which occur with the use of NVGs in flight. Some of the issues addressed include: limitations imposed by a restricted field of view; problems related to binocular rivalry; the consequences of inappropriate focusing of the eye; the effects of ambient illumination levels and of various types of terrain on image quality; difficulties in distance and slope estimation; effects of dazzling; and visual fatigue and superimposed symbology. These issues are described and analyzed in terms of their possible consequences on helicopter pilot performance. The additional influence of individual differences among pilots is emphasized. Thermal imaging systems (forward looking infrared (FLIR)) are described briefly and compared to light intensifier systems (NVGs). Many of the phenomena which are described are not readily understood. More research is required to better understand the human-factors problems created by the use of NVGs and other night-vision aids, to enhance system design, and to improve training methods and simulation techniques.

  13. PAVE LOW III: interior lighting reconfiguration for night lighting and night vision goggle compatibility.

    PubMed

    Task, H L; Griffin, L L

    1982-12-01

    The PAVE LOW III aircraft is a modified HH-53H helicopter that has a low altitude--below 30.48 m (100 ft)--night/day rescue mission. The desired night flying configuration is for the pilot to wear night vision goggles (NVGs) to fly the aircraft while the copilot, without NVGs, observes the video display and monitors the aircraft instruments. The problems of NVG incompatibility in the cockpit were successfully countered using several light control techniques. The light control modifications were evaluated on the ground in the PAVE LOW III helicopter at Kirtland AFB in April, 1980, by PAVE LOW instructor pilots. The evaluation results were extremely positive.

  14. Night vision devices. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Habercom, G. E., Jr.

    1980-08-01

    This bibliography contains 323 citations in which various types of night vision devices are investigated. Most were developed for military applications but they can readily be adapted for civil usage, as for example, law enforcement. Abstracts on display screens, equipment design and effectiveness, electronic components, spurious noise reduction, and test methods are cited.

  15. Low Cost Night Vision System for Intruder Detection

    NASA Astrophysics Data System (ADS)

    Ng, Liang S.; Yusoff, Wan Azhar Wan; R, Dhinesh; Sak, J. S.

    2016-02-01

    The growth in production of Android devices has resulted in greater functionalities as well as lower costs. This has made previously more expensive systems such as night vision affordable for more businesses and end users. We designed and implemented robust and low cost night vision systems based on red-green-blue (RGB) colour histogram for a static camera as well as a camera on an unmanned aerial vehicle (UAV), using OpenCV library on Intel compatible notebook computers, running Ubuntu Linux operating system, with less than 8GB of RAM. They were tested against human intruders under low light conditions (indoor, outdoor, night time) and were shown to have successfully detected the intruders.

  16. Spatial contrast sensitivity through aviator's night vision imaging system.

    PubMed

    Rabin, J

    1993-08-01

    Visual acuity is often used to assess vision through image intensifying devices such as night vision goggles (NVG's). Fewer attempts have been made to measure contrast sensitivity through NVG's. Such information would be useful to better understand contrast processing through NVG's under various stimulus conditions. In this study, computer-generated letter charts were used to measure contrast sensitivity through third generation NVG's for a range of letter sizes. The red phosphor of a standard color monitor proved to be an effective stimulus for third generation devices. Different night sky conditions were simulated over a 3 log unit range. The results illustrate the profile of contrast sensitivity through third generation NVG's over a range of night sky conditions. Comparison of measurements through NVG's to measurements obtained without the device but at the same luminance and color distinguish between effects of luminance and noise on contrast sensitivity.

  17. Wide-field-of-view (WFOV) night vision goggle

    NASA Astrophysics Data System (ADS)

    Isbell, Wayne; Estrera, Joseph P.

    2003-09-01

    The United States' armed forces continue to be presented with increased challenges in adverse operational environments with increasing risk and complexity - especially at night. To ensure continued operational success and battlefield superiority during darkness, our armed forces must be equipped with night vision (NV) systems providing increased situational awareness. Doing so will significantly enhance threat detection and engagement, as well as survivability, thus ensuring greater mission success. Northrop Grumman Electro-Optical Systems (EOS) continues to develop its Wide Field of View (WFOV) image intensification (I2) night vision system for ground forces. This system will provide a significant increase in visual coverage enabling US forces to continue "to own the night". Until now, NV systems have typically been limited to a 40-degree field of view (FOV), vertically and horizontally. This limited FOV reduces off-axis detection, restricts an individual soldier's recognition and engagement capabilities and hinders added peripheral vision. To counter this operational deficiency, EOS proposes the Wide Field of View (WFOV) night vision binocular. The WFOV system will have a 70-degree horizontal FOV, with a 55-degree vertical FOV. The increased FOV will result in increased situational awareness of soldiers' surrounding environment (including terrain, hazards, threat, etc) during normal night operations. It will also allow for rapid and safer movement, especially in MOUT operations. Additionally, the increased visual coverage of large areas will enable soldiers to detect and engage targets faster and with greater reliability. The WFOV binocular will significantly enhance survivability, threat detection and engagement, and hence, greater mission success rate.

  18. What's crucial in night vision goggle simulation?

    NASA Astrophysics Data System (ADS)

    Kooi, Frank L.; Toet, Alexander

    2005-05-01

    Training is required to correctly interpret NVG imagery. Training night operations with simulated intensified imagery has great potential. Compared to direct viewing with the naked eye, intensified imagery is relatively easy to simulate and the cost of real NVG training is high (logistics, risk, civilian sleep deprivation, pollution). On the surface NVG imagery appears to have a structure similar to daylight imagery. However, in actuality its characteristics differ significantly from those of daylight imagery. As a result, NVG imagery frequently induces visual illusions. To achieve realistic training, simulated NVG imagery should at least reproduce the essential visual limitations of real NVG imagery caused by reduced resolution, reduced contrast, limited field-of-view, the absence of color, and the systems sensitivity to nearby infrared radiation. It is particularly important that simulated NVG imagery represents essential NVG visual characteristics, such as the high reflection of chlorophyll and halos. Current real-time simulation software falls short for training purposes because of an incorrect representation of shadow effects. We argue that the development of shading and shadowing merits priority to close the gap between real and simulated NVG flight conditions. Visual conspicuity can be deployed as an efficient metric to measure the 'perceptual distance' between the real NVG and the simulated NVG image.

  19. Chromatic aftereffects associated with a night vision goggle simulation.

    PubMed

    Moffitt, K; Rogers, S P; Cicinelli, J

    1988-02-01

    A visual perception experiment was conducted to determine the chromatic aftereffects of viewing a yellow-green field that simulated the display of current night vision goggles. Six females and two males served as subjects in a color-naming procedure. Subjects sequentially viewed an adaptation field, which was either yellow-green or white, and small colored targets presented on a CRT display. The time required to name the color of the targets was found to be dependent on the color of the adaptation field, the color of the target, and the interaction of these two variables. It was recommended that the effects of attenuation of the luminance of the night vision goggles be studied, and that color cockpit displays be redundantly coded whenever possible.

  20. [Visual efficiency of pilot using of the night vision glasses].

    PubMed

    Davydov, V V; Ivanov, A I; Lapa, V V; Romasiuk, S I; Riabinin, V A; Chuntul, A V; Prokof'ev, A B

    2007-01-01

    Questionnaires filled out by 24 helicopter pilots using the night vision glasses (NVG) showed that minimization of the risk of visual discomfort was, first of all achieved through proper adjustment of image brightness and setting NVG time limits. The experiments enabled determination of the most favorable range of brightness (0.67-1.79 cd/m2) and rationalization of the necessity of individual adjustment depending on the light conditions and flight objectives, and NVG usage regulations to preclude visual fatigue.

  1. Digital Enhancement of Night Vision and Thermal Images

    DTIC Science & Technology

    2003-12-01

    Figure 3: A Night Vision Device with the light amplifying microchannel plate [From Korry, 2003]. 4 A typical II system consists of three main...the device and is focused onto the photocathode by an optical lens system . Photons striking the photocathode surface release photo-electrons. The... generation of NVDs, the energy of the photo-electron is increased by acceleration with an externally applied electric field. Second- generation devices make

  2. Development Of An Aviator's Night Vision Imaging System (ANVIS)

    NASA Astrophysics Data System (ADS)

    Efkernan, Albert; Jenkins, Donald

    1981-04-01

    Historical background is presented of the U. S. Army's requirement for a high performance, lightweight, night vision goggle for use by helicopter pilots. System requirements are outlined and a current program for development of a third generation image intensification device is described. Primary emphasis is on the use of lightweight, precision molded, aspheric plastic optical elements and molded plastic mechanical components. System concept, design, and manufacturing considerations are presented.

  3. Development Of An Aviator's Night Vision Imaging System (ANVIS)

    NASA Astrophysics Data System (ADS)

    Jenkins, Donald; Efkeman, Albert

    1980-10-01

    Historical background is presented of the U.S. Army's requirement for a high performance, lightweight, night vision goggle for use by helicopter pilots. System requirements are outlined and a current program for development of a third generation image intensification device is described. Primary emphasis is on the use of light precision molded, aspheric plastic optical elements and molded plastic mechanical components. System concept, design, and manufacturing considerations are presented.

  4. Visual range of LLL night vision goggle for drive

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Chang, Benkang; Li, Wei; Qian, Yunsheng; Fu, Rongguo; Zhong, Zhiyuan

    2002-09-01

    In this paper, the fundamental theory about visual range of LLL imaging system is described. Based on the revised apparent distance detecting equation and combined with the research intention and design principle of night vision goggle, the relation of parameters which have an influence on performances of system are analyzed. The visual range of the goggle under the specific circumstances is estimated, which proves the revised apparent distance detecting equation is effective and the design of the system is feasible.

  5. All-CMOS night vision viewer with integrated microdisplay

    NASA Astrophysics Data System (ADS)

    Goosen, Marius E.; Venter, Petrus J.; du Plessis, Monuko; Faure, Nicolaas M.; Janse van Rensburg, Christo; Rademeyer, Pieter

    2014-02-01

    The unrivalled integration potential of CMOS has made it the dominant technology for digital integrated circuits. With the advent of visible light emission from silicon through hot carrier electroluminescence, several applications arose, all of which rely upon the advantages of mature CMOS technologies for a competitive edge in a very active and attractive market. In this paper we present a low-cost night vision viewer which employs only standard CMOS technologies. A commercial CMOS imager is utilized for near infrared image capturing with a 128x96 pixel all-CMOS microdisplay implemented to convey the image to the user. The display is implemented in a standard 0.35 μm CMOS process, with no process alterations or post processing. The display features a 25 μm pixel pitch and a 3.2 mm x 2.4 mm active area, which through magnification presents the virtual image to the user equivalent of a 19-inch display viewed from a distance of 3 meters. This work represents the first application of a CMOS microdisplay in a low-cost consumer product.

  6. Modern night vision goggles for advanced infantry applications

    NASA Astrophysics Data System (ADS)

    Estrera, Joseph P.; Ostromek, Timothy E.; Isbell, Wayne; Bacarella, Antonio V.

    2003-09-01

    Northrop Grumman Electro-Optical Systems (NGEOS) has concentrated in recent years on the development of advanced night vision goggle (NVG) systems. These NVGs developments concentrate on past operational deficiencies such as high light/bright source conditions during military operations in urban terrain (MOUT), poor individual movement technique (IMT) infantry operations, and obscured battlefield and reduced weather conditions. The first area of NVG advancement involves direct image intensifier (I2) replacement involving automatic gated power supply technology for wide dynamic NVG operation and advanced Generation III halo free I2 technology for reduction of NVG image halo and "blooming" artifacts. The second significant development area is NVG individual movement technique (IMT) deficiencies such as reduced field of view, reduced depth perception, center of gravity problems, and limited operation flexibility. These issues of NVG IMT have resulted in the development of an IMT enhanced night vision goggle for the U.S. Army's enhanced night vision goggle (ENVG). Finally, Northrop Grumman EOS is developing a NVG with the capability of producing optimized real-time image fusion from an image intensified sensor and uncooled long wavelength infrared (LWIR) sensor. This new technology allows for optimum imaging in battlefield obscured and laser polluted environment. These image fusion NVG development efforts have concentrated on both optical overlay image fusion and digital image fusion. This paper will compare and contrast these two types of image fusion technologies.

  7. AMOLED image source for use in integrated panoramic night vision goggle (IPNVG)

    NASA Astrophysics Data System (ADS)

    Ross, Jeff A.; Parisi, Vince

    2004-09-01

    The objective of this paper is to present an overview of the active matrix organic light emitting diode (OLED) microdisplay used in the integrated panoramic night vision goggle (IPNVG). These devices will be used to insert independent and overlaid video imagery into the IPNVG. Interface and operational details of the microdisplay relative to the IPNVG implementation in military aircraft will be discussed.

  8. Uniform calibration of night vision goggles and test sets

    NASA Astrophysics Data System (ADS)

    Eppeldauer, George P.

    2007-10-01

    There are orders of magnitude differences between the ~0.1 % (k=2) uncertainty of NIST reference detector calibrations and the uncertainty of night vision (NV) goggle measurements. NIST developed a night vision radiometer calibration facility including NV radiometer transfer standards. The transfer standards, that propagate the radiance responsivity scale to the military primary standards laboratories, are calibrated against a NIST reference radiometer. The reference radiometer has been calibrated on the NIST Spectral Comparator Facility (SCF) for spectral power and irradiance responsivities. Spectral considerations are discussed to lower the uncertainties of the radiance responsivity scale transfer to the test sets and then to the goggles. Since direct determination of the final uncertainties in goggle calibrations and measurements is difficult, models have been made to estimate the most important uncertainty components based on individual spectral measurements of the applied source distributions and radiometer spectral responsivities. It is also shown, that because of source spectral mismatch problems, the goggle measurement uncertainty at applications can be much higher than at calibration. A suggestion is being made to mimic the no-moon (stars only) night sky radiation distribution using several LEDs in the test-sets to decrease the large spectral mismatch errors. A broad-band correction factor has been developed to further decrease calibration uncertainty when the goggles to be used have different spectral responsivities than the standard. Geometrical considerations to optimize the radiance measurement angle and the out-of-target blocking are also discussed to decrease the uncertainty in the radiance responsivity transfer.

  9. Mild hypoxia and visual performance with night vision goggles.

    PubMed

    Leber, L L; Roscoe, S N; Southward, G M

    1986-04-01

    Military night vision goggles (NVGs) are image intensifiers normally used when the human operator's visual capabilities are unimpaired by oxygen deprivation. However, mountain search team members and aviators sometimes operate with NVG augmentation at altitudes where hypoxic visual decrement is documented. The objective of this research was to investigate the effects of mild hypoxia on monocular visual performance with NVGs. It was found that mild oxygen deprivation significantly affects unaided square-wave grating visual acuity but does not significantly affect NVG-augmented performance. Large differences between visual sensitivities at different spatial frequencies were not differentially affected by mild hypoxia. Supplemental oxygen did significantly improve naked-eye but not NVG-augmented night resolution acuity up to a simulated altitude of 13,000 ft (3,962 m) above sea level (ASL).

  10. Prevention of facial fractures from night vision goggle impact.

    PubMed

    Manoogian, Sarah; Kennedy, Eric; Wilson, Kaitlin; Duma, Stefan

    2006-01-01

    Facial bone fractures in the military can result from direct loading of night vision goggles on the orbital region. Facial fracture research has shown that increasing the area over which the load is applied increases the load tolerance. The purpose of this study is to apply this concept to reducing the risk of facial bone fracture from night vision goggle impacts. The effectiveness of countermeasures in prevention of orbital fracture was evaluated using a vertical drop tower with two impact velocities of 2.6 m/s and 3.6 m/s. The countermeasure used was a rigid plastic custom face shield made from a plaster impression of each head. In addition to two human cadaver subjects, one male and one female, tests were completed on a Hybrid III 50th percentile dummy head. Three impacts to the dummy headform included no countermeasure, safety glasses, and a custom face shield. These tests yielded peak loads of 8700 N, 7500 N, and 5640 N respectively. Using the female subject, impacts were preformed successively until injury occurred. These two impacts to the subject wearing a custom face shield resulted in peak loads of 4025 N and 5158 N. The highest load corresponds to an impact velocity of 3.6 m/s and a nasal bone fracture. Two impacts to the male subject with a custom face shield resulted in peak loads of 4554 N and 5101 N with no injury. The final impact to the male subject had a peak load of 2010 N with complete orbital fracture due to the absence of a countermeasure. From these tests it is shown that facial fracture risk from night vision goggle impact can be reduced using a contoured rigid face shield.

  11. Some thoughts on the implementation of pilot night vision devices for helicopters

    NASA Technical Reports Server (NTRS)

    Tucker, G. E.

    1984-01-01

    Night vision enhancement devices greatly expand the range and quality of services by extending night operational capabilities. Evolving military tactical concepts for helicopters survivability and battlefield effectiveness necessitate nap-of-the-earth (NOE) flying under both day and night conditions. From a pilot workload standpoint, flying a helicopter NOE in day VFR conditions with minimum clearance between rotors and obstacles is quite demanding. Doing the same job at night is several times more difficult. There are two general categories of night vision devices in operation in helicopter aviation: the Night Vision Goggles (NVG) and forward looking infrared (FLIR) system. The capabilities and limitations of those two devices are discussed.

  12. Design of three-element night-vision goggle objectives.

    PubMed

    Rouke, J L; Crawford, M K; Fischer, D J; Harkrider, C J; Moore, D T; Tomkinson, T H

    1998-02-01

    Night-vision goggle objectives are often composed of six or more conventional lens elements with spherical surfaces and homogeneous refractive indices. Special elements such as aspheres, diffractive optics, and gradient-index materials can be used to reduce the total number of lenses required to meet military design specifications. A study was performed to examine the use of various combinations of these special surfaces to determine the minimum number of elements that can be used to construct the objective system. We present and compare the best resulting designs.

  13. Night vision goggles, laser eye protection, and cockpit displays

    NASA Astrophysics Data System (ADS)

    Martinsen, Gary; Havig, Paul; Dykes, James; Kuyk, Thomas; McLin, Leon

    2007-04-01

    The increasing use of lasers on the modern battlefield may necessitate the wear of laser eye protection devices (LEPDs) by warfighters. Unfortunately, LEPDs that protect against visible laser wavelengths often reduce overall light transmittance and a wearer's vision can be degraded, especially in low light conditions. Wearing night vision goggles (NVGs) provides laser eye protection behind the goggles, but NVGs do not block lasers that might enter the eye around the NVGs. Therefore, LEPDs will be worn under NVGs. People wearing NVGs look below the NVGs to read displays and for other near vision tasks. This effort involved determining the effects of wearing variable density filters on vision in low light conditions, with and without the presence of a simulated head-down display (HDD). Each subject's visual acuity was measured under moonlight illumination levels while wearing neutral density filters and LEPDs. Similar measurements of the subjects' visual detection thresholds, both on and off-axis, were made. Finally, the effects of wearing variable density filters on visual acuity on the HDD were determined. Wearing variable density filters in low-light conditions reduces visual acuity and detection. The presence of the HDD reduced acuity slightly through variable density filters but. the HDD had no effect on on-axis detection and actually improved off-axis detection. The reasons for this final finding are unclear.

  14. Depth perception after prolonged usage of night vision goggles.

    PubMed

    Sheehy, J B; Wilkinson, M

    1989-06-01

    The present study was initiated following a report that a few helicopter pilots had failed a test of stereoscopic depth perception after a prolonged training flight employing night vision goggles (NVGs). In order to determine the cause of the loss, 12 helicopter pilots/copilots were assessed for depth perception, lateral and vertical phoria, and contrast sensitivity before and after training flights requiring the pilots to wear night vision goggles for the duration of the flight. Pilots flew one to three missions while wearing either PVS-5A or AN/AVS-6 goggles. Mission duration ranged from 1 to 4 h. The results indicate that contrast sensitivity and depth perception when monocular cues are present did not degrade over the course of the mission. Lateral phoria, however, did demonstrate an average exophoric shift of 1.5 prism diopters for 12 out of the 24 missions. The results indicate that the original report of a loss of depth perception based on a test of depth requiring stereopsis might have been caused by a shift in lateral phoria. It would be expected that as additional fusional effort is required, the minimum resolvable disparity degrades due to the increase in accommodation brought about through vergence accommodation. Possible causes for the phoria shift and future testing are discussed.

  15. Assessment of panoramic and conventional night vision goggles

    NASA Astrophysics Data System (ADS)

    Thorndycraft, David

    2003-09-01

    This paper presents results obtained during a flight evaluation of Night Vision Devices (NVDs) equipped with a symbology injection capability. The NVDs used represented both conventional and wide (Panoramic) Field of View Night Vision Goggle (PNVG) systems. The evaluation was conducted at the National Research Council of Canada Bell 205 Flying Simulator under the auspices of the Technical Co-operation Programme. 6 Pilots from 4 nations participated in the trial and some 36 hours of flight data and pilot performance were recorded. The metrics used to evaluate Pilot performance included conventional Visual Cue Ratings, estimates of workload, and objective measures obtained through advanced data-analysis techniques. The trial used both conventional ADS-33D manoeuvres and a novel 'Racetrack" course. The paper concludes that although PNVG compare favourably with NVGs the clarity of image currently available in standard NVGs surpasses that of the PNVG and negates some of the advantages gained by the wider Field of View. The manoeuvres favoured by the NVG include those where a high degree of foveal attention demanding processing is being performed, for example navigation tasks. The manoeuvres favoured by the PNVG include those where a more automatic peripheral processing is being performed, for example in reducing drift in the hover.

  16. New weather depiction technology for night vision goggle (NVG) training

    NASA Astrophysics Data System (ADS)

    Theleman, Scott; Hegarty, Jennifer; Vollmerhausen, Richard; Scott, Courtney; Schroeder, John; Colby, Frank P.; Napier, S.

    2006-08-01

    US Navy and Marine Corps pilots receive Night Vision Goggle (NVG) training as part of their overall training to maintain the superiority of our forces. This training must incorporate realistic targets; backgrounds; and representative atmospheric and weather effects they may encounter under operational conditions. An approach for pilot NVG training is to use the Night Imaging and Threat Evaluation Laboratory (NITE Lab) concept. The NITE Labs utilize a 10' by 10' static terrain model equipped with both natural and cultural lighting that are used to demonstrate various illumination conditions, and visual phenomena which might be experienced when utilizing night vision goggles. With this technology, the military can safely, systematically, and reliably expose pilots to the large number of potentially dangerous environmental conditions that will be experienced in their NVG training flights. This paper describes work that is being performed for NAVAIR to add realistic atmospheric and weather effects to the NVG NITE Lab training facility using the NVG-WDT (Weather Dipiction Technology) system. NVG-WDT consist of a high end multiprocessor server with weather simulation software, and several fixed and goggle mounted Heads Up Displays (HUDs). Atmospheric and weather effects are simulated using state-of-the-art computer codes such as the NCAR/Penn State Mesoscale Model (MM5); and the US Air Force Research Laboratory MODTRAN radiative transport model. Imagery for a variety of natural and man-made obscurations (e.g. rain, clouds, snow, dust, smoke, chemical releases) is being calculated and injected into the scene observed through the NVG via the fixed and goggle mounted HUDs.

  17. Night Vision and Electro-Optics Technology Transfer, 1972-1981

    DTIC Science & Technology

    1981-09-15

    night blindness can now purchase a small image intensifier to improve their vision? Image intensifiers have also been used in eye re- search, in...Avoidance for the Blind ......................................... 13 Eye Research and Image Intensifiers ....................................... 14 Low...NV&EOL’s work in these areas. NIGHT VISION TECHNOLOGIES Night Vision and the Electromagnetic Spectrum The human eye and many man-made devices such as

  18. Acoustic Measurement and Model Predictions for the Aural Nondetectability of Two Night-Vision Goggles

    DTIC Science & Technology

    2013-11-01

    Acoustic Measurement and Model Predictions for the Aural Nondetectability of Two Night - Vision Goggles by Jeremy Gaston, Tim Mermagen, and...SUBTITLE Acoustic Measurement and Model Predictions for the Aural Nondetectability of Two Night - Vision Goggles 5a. CONTRACT NUMBER 5b. GRANT NUMBER...13. SUPPLEMENTARY NOTES 14. ABSTRACT This study evaluates two different night - vision goggles (NVGs) to determine if the devices meet level II

  19. Development of the combiner-eyepiece night-vision goggle

    NASA Astrophysics Data System (ADS)

    Cameron, Alexander A.

    1990-10-01

    Conventional 'straightthrough ' nightvision goggles are now in widespread service with many armed forces throughout the world. Though originally designed for ground forces they have been successfully engineered into the airborne environment and are used on both rotary wing and fixed wing aircraft. However, a major disadvantage in the use of this type of NVG, particularly in fast jet applications, is that they obscure the pilots direct view of the Head Up Display. The combiner eyepiece NVGs solves this problem by giving the pilot a direct view of the HUD and cockpit instruments which is optically combined with the intensified image. The cockpit instruments and HUD are ofcourse compatible with the NVG and are invisible to the NVG. The development ofa Combiner eyepiece NVG from initial concept through to production isdiscussed including design considerations, trade offs and enhancements to the operation of the device. The further development of the combiner eyepiece NVG into a fully integrated ejection safe night vision helmet is also described.

  20. Helmet-mounted pilot night vision systems: Human factors issues

    NASA Technical Reports Server (NTRS)

    Hart, Sandra G.; Brickner, Michael S.

    1989-01-01

    Helmet-mounted displays of infrared imagery (forward-looking infrared (FLIR)) allow helicopter pilots to perform low level missions at night and in low visibility. However, pilots experience high visual and cognitive workload during these missions, and their performance capabilities may be reduced. Human factors problems inherent in existing systems stem from three primary sources: the nature of thermal imagery; the characteristics of specific FLIR systems; and the difficulty of using FLIR system for flying and/or visually acquiring and tracking objects in the environment. The pilot night vision system (PNVS) in the Apache AH-64 provides a monochrome, 30 by 40 deg helmet-mounted display of infrared imagery. Thermal imagery is inferior to television imagery in both resolution and contrast ratio. Gray shades represent temperatures differences rather than brightness variability, and images undergo significant changes over time. The limited field of view, displacement of the sensor from the pilot's eye position, and monocular presentation of a bright FLIR image (while the other eye remains dark-adapted) are all potential sources of disorientation, limitations in depth and distance estimation, sensations of apparent motion, and difficulties in target and obstacle detection. Insufficient information about human perceptual and performance limitations restrains the ability of human factors specialists to provide significantly improved specifications, training programs, or alternative designs. Additional research is required to determine the most critical problem areas and to propose solutions that consider the human as well as the development of technology.

  1. Detection of Special Operations Forces Using Night Vision Devices

    SciTech Connect

    Smith, C.M.

    2001-10-22

    Night vision devices, such image intensifiers and infrared imagers, are readily available to a host of nations, organizations, and individuals through international commerce. Once the trademark of special operations units, these devices are widely advertised to ''turn night into day''. In truth, they cannot accomplish this formidable task, but they do offer impressive enhancement of vision in limited light scenarios through electronically generated images. Image intensifiers and infrared imagers are both electronic devices for enhancing vision in the dark. However, each is based upon a totally different physical phenomenon. Image intensifiers amplify the available light energy whereas infrared imagers detect the thermal energy radiated from all objects. Because of this, each device operates from energy which is present in a different portion of the electromagnetic spectrum. This leads to differences in the ability of each device to detect and/or identify objects. This report is a compilation of the available information on both state-of-the-art image intensifiers and infrared imagers. Image intensifiers developed in the United States, as well as some foreign made image intensifiers, are discussed. Image intensifiers are categorized according to their spectral response and sensitivity using the nomenclature of GEN I, GEN II, and GEN III. As the first generation of image intensifiers, GEN I, were large and of limited performance, this report will deal with only GEN II and GEN III equipment. Infrared imagers are generally categorized according to their spectral response, sensor materials, and related sensor operating temperature using the nomenclature Medium Wavelength Infrared (MWIR) Cooled and Long Wavelength Infrared (LWIR) Uncooled. MWIR Cooled refers to infrared imagers which operate in the 3 to 5 {micro}m wavelength electromagnetic spectral region and require either mechanical or thermoelectric coolers to keep the sensors operating at 77 K. LWIR Uncooled refers

  2. Detection of motion-defined form using night vision goggles

    NASA Astrophysics Data System (ADS)

    Macuda, Todd; Craig, Greg; Allison, Robert S.; Guterman, Pearl; Thomas, Paul; Jennings, Sion

    2005-05-01

    Perception of motion-defined form is important in operational tasks such as search and rescue and camouflage breaking. Previously, we used synthetic Aviator Night Vision Imaging System (ANVIS-9) imagery to demonstrate that the capacity to detect motion-defined form was degraded at low levels of illumination (see Macuda et al., 2004; Thomas et al., 2004). To validate our simulated NVG results, the current study evaluated observer"s ability to detect motion-defined form through a real ANVIS-9 system. The image sequences consisted of a target (square) that moved at a different speed than the background, or only depicted the moving background. For each trial, subjects were shown a pair of image sequences and required to indicate which sequence contained the target stimulus. Mean illumination and hence image noise level was varied by means of Neutral Density (ND) filters placed in front of the NVG objectives. At each noise level, we tested subjects at a series of target speeds. With both real and simulated NVG imagery, subjects had increased difficulty detecting the target with increased noise levels, at both slower and higher target speeds. These degradations in performance should be considered in operational planning. Further research is necessary to expand our understanding of the impact of NVG-produced noise on visual mechanisms.

  3. Light source halos in night vision goggles: psychophysical assessments

    NASA Astrophysics Data System (ADS)

    Craig, Greg; Macuda, Todd; Thomas, Paul; Allison, Rob; Jennings, Sion

    2005-05-01

    Anecdotal reports by pilots flying with Night Vision Goggles (NVGs) in urban environments suggest that halos produced by bright light sources impact flight performance. The current study developed a methodology to examine the impact of viewing distance on perceived halo size. This was a first step in characterizing the subtle phenomenon of halo. Observers provided absolute size estimates of halos generated by a red LED at several viewing distances. Physical measurements of these halos were also recorded. The results indicated that the perceived halo linear size decreased as viewing distance was decreased. Further, the data showed that halos subtended a constant visual angle on the goggles (1°48", +/-7") irrespective of distance up to 75". This invariance with distance may impact pilot visual performance. For example, the counterintuitive apparent contraction of halo size with decreasing viewing distance may impact estimates of closure rates and of the spatial layout of light sources in the scene. Preliminary results suggest that halo is a dynamic phenomenon that requires further research to characterize the specific perceptual effects that it might have on pilot performance.

  4. Night vision in Thales Angenieux: custom solutions for handheld devices

    NASA Astrophysics Data System (ADS)

    Rollin, Joel; Teszner, Jean Louis; Delic, Gilles; Espie, Jean Luc; Sigonnaud, Eric

    2004-08-01

    Thales Angenieux has been developing for almost two decades, compact and flexible light intensifier goggles that are in service through numerous countries. More recently, a new product line, called Elvir, has been launched which is based upon uncooled sensitive arrays: as a consequence, Thales Angenieux has now at command a full set of night vision equipment's, answering most of the operational purposes. A 'blocks' policy has been used to cut the non-recurring expenses: the thermal camera re-uses some upgraded sub-assemblies of the previous IL goggles. This paper reviews the main trades off, showing how we relied on earlier and successful designs to meet the best compromises between performances, costs and compactness. Some issues, such as the front infrared optics set up, will be emphasized later on. The choices that have ruled the visualization unit design will be outlined. Future prospects backing the latest technologies breakthroughs wil be sketched out: topics such as new infrared materials and hybrid lenses made of subwavelength features are addressed.

  5. A Decade Of Development In Passive Night Vision Goggles

    NASA Astrophysics Data System (ADS)

    Rogers, Philip J.

    1980-09-01

    Work carried out at PPE over the last ten years has resulted in the development of four head-mounted passive night vision goggles of unity magnification. Considered in relation to each other, these systems illustrate the technical progression from the oriainal sight, a twin image intensifier tube device that employed conventional optics, through a series of three single tube goggles of decreasing complexity, weight and cost. The MkI and MkII single tube devices, of beamsplitter/relay lens and collimator/multireflector design respectively, required precise manufacture: the later of the two designs, however,was both simpler in construction and more advanced in technical specification than the earlier. The concept of the MkIII single tube goggle was influenced by the lower relative cost of current intensifier tubes and resulted in a lens design that can be fabricated in its entirety in optical plastics. Compared with the original two tube goggle, the final system has a similar technical specification but is much cheaper and less than half the weight. The paper describes the optical design philosophy behind each goggle and the evolution of each subsequent stage.

  6. Night vision goggle luminance disparity and the Pulfrich phenomenon

    NASA Astrophysics Data System (ADS)

    Pinkus, Alan; Task, Harry L.

    2004-09-01

    When night vision goggle (NVG) image intensifier tubes (I2Ts) are replaced during maintenance, the output luminances of the two channels must not exceed a ratio of 1.5 (brighter channel luminance divided by the dimmer channel luminance) in order to meet the current allowed binocular luminance disparity specification. Two studies were performed to investigate the validity of this requirement. The first study estimated thresholds of binocular luminance disparity detection for observers looking through NVGs. For eight observers, the 25% corrected-for-chance probability of detecting an ocular luminance difference, yielded an average ratio of 1.43 indicating that the current 1.5 specification is perhaps too loose. The second study investigated the Pulfrich phenomenon, a pseudo-stereo effect that can be induced by presenting luminance imbalances to the eyes. This study created NVG luminance imbalances using neutral density (ND) filters and then investigated whether or not the various imbalance levels were sufficient to cause the Pulfrich phenomenon to be perceived. Results indicated an imbalance ratio of 1.10 was insufficient to cause the effect to be seen, but a ratio of 1.26 was sufficient (p <= 0.0003) for the effect to be seen, at least part of the time. Based on these results, it is apparent the allowed binocular luminance disparity ratio should probably be tightened to at least 1.3 with a goal of 1.2.

  7. Novel approach to characterize and compare the performance of night vision systems in representative illumination conditions

    NASA Astrophysics Data System (ADS)

    Roy, Nathalie; Vallières, Alexandre; St-Germain, Daniel; Potvin, Simon; Dupuis, Michel; Bouchard, Jean-Claude; Villemaire, André; Bérubé, Martin; Breton, Mélanie; Gagné, Guillaume

    2016-05-01

    A novel approach is used to characterize and compare the performance of night vision systems in conditions more representative of night operation in terms of spectral content. Its main advantage compared to standard testing methodologies is that it provides a fast and efficient way for untrained observers to compare night vision system performances with realistic illumination spectra. The testing methodology relies on a custom tumbling-E target and on a new LED-based illumination source that better emulates night sky spectral irradiances from deep overcast starlight to quarter-moon conditions. In this paper, we describe the setup and we demonstrate that the novel approach can be an efficient method to characterize among others night vision goggles (NVG) performances with a small error on the photogenerated electrons compared to the STANAG 4351 procedure.

  8. Novel night vision goggles (NVG) based on image intensifiers with twister

    NASA Astrophysics Data System (ADS)

    Loktionov, V. I.; Edin, V. A.; Kochmarev, A. V.; Kasatsky, Y. V.

    2005-06-01

    In this report the new developed is described, essence of that is improvement of optical scheme of night vision goggles, introductions I2 with twister. The result of this improvement is device entire mass dimensions decrease.

  9. Development, Testing and Evaluation of a Night Vision Goggle Compatible BO-105 for Night Low Level Operation,

    DTIC Science & Technology

    Stability Augmentation System ), a Doppler Navigation System with Mapreader, a TACAN and recording equipment were installed in the test helicopter. In a pre-evaluation program, two types of helmet mounted Night Vision Goggles (NVG’s) were selected for further evaluation. After the 2 axis SAS had been replaced by a 3 axis CSAS and NVG compatible cockpit lighting had been installed in the test helicopter, night low level operational flight trials were carried out. This paper describes the selection of the NVG’s the NVG compatible lighting and presents the

  10. Selective Factors Affecting Rotary Wing Aviator Performance with Symbology Superimposed on Night Vision Goggles

    DTIC Science & Technology

    1992-07-01

    Coren, 1976; 1986), total dominance of one eye for extended periods is rare ( Arditi , 1986; Beaton, 1985). 7 Night Vision Goggles NVGs are binocular...Engineering. Arditi , A. (1986). Binocular vision. In K. R. Boff, L. Kaufman, & J. P. Thomas (Eds.), Handbook of perceptual and human performance. Vol. I (pp

  11. A Most Rare Vision: Improvisations on "A Midsummer Night's Dream."

    ERIC Educational Resources Information Center

    Hakaim, Charles J., Jr.

    1993-01-01

    Describes one teacher's methods for introducing to secondary English students the concepts of improvisation, experimentation, and innovation. Discusses numerous techniques for fostering such skills when working with William Shakespeare's "A Midsummer Night's Dream." (HB)

  12. Focus adjustment effects on visual acuity and oculomotor balance with aviator night vision displays.

    PubMed

    Kotulak, J C; Morse, S E

    1994-04-01

    Sixteen U.S. Army aviators, who were given training on focus adjustment technique with aviator night vision goggles (NVG), showed an improvement in visual acuity with focus adjustment compared to a fixed infinity focus control. The long-term effect of focus adjustment on vision was not measured; however, adjustment accuracy was found to be generally within acceptable limits based on computer modeling and available physiologic data. Fixed focus eyepieces that are set to a low minus power may partially compensate for instrument myopia, but they may not optimize visual acuity to the extent that adjustable focus eyepieces do. Eyepiece adjustment proficiency with present night vision devices can be improved through training that emphasizes focusing to the least possible minus dioptric power. Future night vision displays can minimize focus misadjustment by providing a tactile zero marking, a limited dioptric adjustment range, and a focusing knob capable of finer adjustment than is available with current NVG's.

  13. Night vision imaging systems design, integration, and verification in military fighter aircraft

    NASA Astrophysics Data System (ADS)

    Sabatini, Roberto; Richardson, Mark A.; Cantiello, Maurizio; Toscano, Mario; Fiorini, Pietro; Jia, Huamin; Zammit-Mangion, David

    2012-04-01

    This paper describes the developmental and testing activities conducted by the Italian Air Force Official Test Centre (RSV) in collaboration with Alenia Aerospace, Litton Precision Products and Cranfiled University, in order to confer the Night Vision Imaging Systems (NVIS) capability to the Italian TORNADO IDS (Interdiction and Strike) and ECR (Electronic Combat and Reconnaissance) aircraft. The activities consisted of various Design, Development, Test and Evaluation (DDT&E) activities, including Night Vision Goggles (NVG) integration, cockpit instruments and external lighting modifications, as well as various ground test sessions and a total of eighteen flight test sorties. RSV and Litton Precision Products were responsible of coordinating and conducting the installation activities of the internal and external lights. Particularly, an iterative process was established, allowing an in-site rapid correction of the major deficiencies encountered during the ground and flight test sessions. Both single-ship (day/night) and formation (night) flights were performed, shared between the Test Crews involved in the activities, allowing for a redundant examination of the various test items by all participants. An innovative test matrix was developed and implemented by RSV for assessing the operational suitability and effectiveness of the various modifications implemented. Also important was definition of test criteria for Pilot and Weapon Systems Officer (WSO) workload assessment during the accomplishment of various operational tasks during NVG missions. Furthermore, the specific technical and operational elements required for evaluating the modified helmets were identified, allowing an exhaustive comparative evaluation of the two proposed solutions (i.e., HGU-55P and HGU-55G modified helmets). The results of the activities were very satisfactory. The initial compatibility problems encountered were progressively mitigated by incorporating modifications both in the front and

  14. The impact of target luminance and radiance on night vision device visual performance testing

    NASA Astrophysics Data System (ADS)

    Marasco, Peter L.; Task, H. Lee

    2003-09-01

    Visual performance through night-vision devices (NVDs) is a function of many parameters such as target contrast, objective and eyepiece lens focus, signal/noise of the image intensifier tube, quality of the image intensifier, night-vision goggle (NVG) gain, and NVG output luminance to the eye. The NVG output luminance depends on the NVG sensitive radiance emitted (or reflected) from the visual acuity target (usually a vision testing chart). The primary topic of this paper is the standardization (or lack thereof) of the radiance levels used for NVG visual acuity testing. The visual acuity chart light level might be determined in either photometric (luminance) units or radiometric (radiance) units. The light levels are often described as "starlight," "quarter moon," or "optimum" light levels and may not actually provide any quantitative photometric or radiometric information. While these terms may be useful to pilots and the users of night-vision devices, they are inadequate for accurate visual performance testing. This is because there is no widely accepted agreement in the night vision community as to the radiance or luminance level of the target that corresponds to the various named light levels. This paper examines the range of values for "starlight," "quarter moon," and "optimum" light commonly used by the night vision community and referenced in the literature. The impact on performance testing of variations in target luminance/radiance levels is also examined. Arguments for standardizing on NVG-weighted radiometric units for testing night-vision devices instead of photometric units are presented. In addition, the differences between theoretical weighted radiance and actual weighted radiance are also discussed.

  15. An assessment of a proposed method for adjusting and focusing ANVIS night vision goggles.

    PubMed

    Manton, A G

    1996-02-01

    Night vision goggles are becoming an increasingly important tool in military aviation. They provide superior visual capability over unaided night vision, but any reduction in goggle performance can have a serious effect on flight safety and operational effectiveness. This study shows that the use of a standard adjustment procedure in a night vision goggle (NVG) test lane, with a resolution chart, provides an effective method for aircrew to obtain better visual capability than is currently obtained by focusing on distant features of the landscape. Visual acuity (VA) was measured for 20 aircrew representing all crew positions, after using both the current adjustment method and the proposed method for adjusting ANVIS NVGs. The average visual acuity showed an improvement from 6/19 (s.d. = 3.9) with the current method to 6/13 (s.d. = 2.8) with the proposed method. However, NVG test lanes cannot be used with goggles which have fixed infinity objective lenses eg Nite.

  16. Measuring Observers’ Visual Acuity Through Night Vision Goggles

    DTIC Science & Technology

    1998-01-01

    a two-alternative, forced-choice ( 2AFC ) method to determine visual acuity through NVGs as a function of night-time ambient illumination levels. A...computer executed the 2AFC (gap seen up or down), Step Program adapted from Simpson (1989). Based on the observerÕs last response, the program selected...threshold levels, NVG drift, good guessing in the 2AFC method, fatigue, eye strain, sinus headaches and so on. METHOD Psychometric Function of Acuity

  17. Peripheral vision horizon display on the single seat night attack A-10

    NASA Technical Reports Server (NTRS)

    Nims, D. F.

    1984-01-01

    The concept of the peripheral vision horizon display (PVHD) held promise for significant reduction in workload for the single seat night attack pilot. For this reason it was incorporated in the single seat night attack (SSNA) A-10. The implementation and results of the PVHD on the SSNA A-10 are discussed as well as the SSNA program. The part the PVHD played in the test and the results and conclusions of that effort are also considered.

  18. Night vision: requirements and possible roadmap for FIR and NIR systems

    NASA Astrophysics Data System (ADS)

    Källhammer, Jan-Erik

    2006-04-01

    A night vision system must increase visibility in situations where only low beam headlights can be used today. As pedestrians and animals have the highest risk increase in night time traffic due to darkness, the ability of detecting those objects should be the main performance criteria, and the system must remain effective when facing the headlights of oncoming vehicles. Far infrared system has been shown to be superior to near infrared system in terms of pedestrian detection distance. Near infrared images were rated to have significantly higher visual clutter compared with far infrared images. Visual clutter has been shown to correlate with reduction in detection distance of pedestrians. Far infrared images are perceived as being more unusual and therefore more difficult to interpret, although the image appearance is likely related to the lower visual clutter. However, the main issue comparing the two technologies should be how well they solve the driver's problem with insufficient visibility under low beam conditions, especially of pedestrians and other vulnerable road users. With the addition of an automatic detection aid, a main issue will be whether the advantage of FIR systems will vanish given NIR systems with well performing automatic pedestrian detection functionality. The first night vision introductions did not generate the sales volumes initially expected. A renewed interest in night vision systems are however to be expected after the release of night vision systems by BMW, Mercedes and Honda, the latter with automatic pedestrian detection.

  19. Night vision goggles, human factors aspects--a questionnaire survey of helicopter aircrew.

    PubMed

    Manton, A G

    2000-02-01

    Night vision goggles have become an essential component of military aviation. They provide superior visual capability over unaided night vision, but there are several inherent limitations associated with human factors and systems limitations. This study used a questionnaire survey of Army helicopter aircrew to investigate the incidence of human factors problems which continued after NVG use, with particular reference to visual problems and neck discomfort. It also looked at hardware interaction problems, such as cockpit lighting, and other aspects of NVG use, such as training and aircrew concerns. The issues are described and analysed, and areas of concern, which may have bearings on operational effectiveness and/or safety, have been highlighted.

  20. Perceptual adaptation in the use of night vision goggles

    NASA Technical Reports Server (NTRS)

    Durgin, Frank H.; Proffitt, Dennis R.

    1992-01-01

    The image intensification (I sup 2) systems studied for this report were the biocular AN/PVS-7(NVG) and the binocular AN/AVS-6(ANVIS). Both are quite impressive for purposes of revealing the structure of the environment in a fairly straightforward way in extremely low-light conditions. But these systems represent an unusual viewing medium. The perceptual information available through I sup 2 systems is different in a variety of ways from the typical input of everyday vision, and extensive training and practice is required for optimal use. Using this sort of system involves a kind of perceptual skill learning, but is may also involve visual adaptations that are not simply an extension of normal vision. For example, the visual noise evident in the goggles in very low-light conditions results in unusual statistical properties in visual input. Because we had recently discovered a strong and enduring aftereffect of perceived texture density which seemed to be sensitive to precisely the sorts of statistical distortions introduced by I sup 2 systems, it occurred to use that visual noise of this sort might be a very adapting stimulus for texture density and produce an aftereffect that extended into normal vision once the goggles were removed. We have not found any experimental evidence that I sup 2 systems produce texture density aftereffects. The nature of the texture density aftereffect is briefly explained, followed by an accounting of our studies of I sup 2 systems and our most recent work on the texture density aftereffect. A test for spatial frequency adaptation after exposure to NVG's is also reported, as is a study of perceived depth from motion (motion parallax) while wearing the biocular goggles. We conclude with a summary of our findings.

  1. Civil Use of Night Vision Devices - Evaluation Pilot’s Guide, Part 1

    DTIC Science & Technology

    1994-07-01

    expected Near surtace ve- i switches on the computer that drives the I also adjusted HUD intencity while look- etation dunng hover and slow-speed...overhead HUD data can be overlaid on ar. I dcispla% litit all night-vision goggles do require at equates to 100% ambient light, quarter without deg

  2. Modulation transfer function as a predictor of visual acuity using a night vision device

    NASA Astrophysics Data System (ADS)

    Fullenkamp, S. C.; Trissell, T. L.; Aleva, D. L.; Dixon, S.; Task, H. L.

    2005-05-01

    Night Vision Goggles (NVGs) are being used increasingly by the military and law enforcement agencies for night operations. One critical issue in assessing the utility of an NVG is its resolving power or capability to make fine detail distinguishable. The resolution of Night Vision Goggles is typically assessed by measuring the visual acuity of an operator looking through the goggles. These methods can be time consuming. Further, inconsistencies associated with visual observations and judgement add to the variance associated with these measurements. NVG Modulation Transfer Function (MTF) was explored as a possible means of characterizing NVG image quality independent of a human observer. MTF maps the potential contrast output of the NVGs as a function of spatial frequency. The results of this MTF measurement were compared with a commonly used method of visual acuity assessment.

  3. Is there an optimum detector size for digital night vision goggles?

    NASA Astrophysics Data System (ADS)

    Holst, Gerald C.

    2016-05-01

    In previous studies maximum acquisition range was achieved when Fλ/d approached 2. There was no constraint on magnification or field-of-view. This suggested that detector size approach λ/2 when F = 1. Night vision goggles typically have a fixed FOV of 40 deg with unity magnification. Digital night vision goggles (DNVG) acquisition range is limited by the human visual system resolution of 0.291 mrad (20/20 vision). This suggests the maximum number of horizontal detectors should be about 2500 with a minimum pixel size of about 8 μm when F = 1 and aperture = 1 inch. Values change somewhat depending upon f-number and noise level. Ranges are provided for GaAs and InGaAs detectors under starlight conditions. The different spectral responses create minimum resolvable contrast (MRC) test issues.

  4. Color night vision system for ground vehicle navigation

    NASA Astrophysics Data System (ADS)

    Ali, E. A.; Qadir, H.; Kozaitis, S. P.

    2014-06-01

    Operating in a degraded visual environment due to darkness can pose a threat to navigation safety. Systems have been developed to navigate in darkness that depend upon differences between objects such as temperature or reflectivity at various wavelengths. However, adding sensors for these systems increases the complexity by adding multiple components that may create problems with alignment and calibration. An approach is needed that is passive and simple for widespread acceptance. Our approach uses a type of augmented display to show fused images from visible and thermal sensors that are continuously updated. Because the raw fused image gave an unnatural color appearance, we used a color transfer process based on a look-up table to replace the false colors with a colormap derived from a daytime reference image obtained from a public database using the GPS coordinates of the vehicle. Although the database image was not perfectly registered, we were able to produce imagery acquired at night that appeared with daylight colors. Such an approach could improve the safety of nighttime navigation.

  5. Compatibility of the aviation night vision imaging systems and the aging aviator.

    PubMed

    Farr, W D

    1989-10-01

    With the advent of the night vision goggle (NVG) mission requirements in the United States Army, the reserve components began training with the second generation (AN/PVS-5 & AN/PVS-5A) systems. These systems prohibit the wear of spectacles by the aviator. Certain modifications on some systems allowed for spectacle wear. However, there still exists a 5-h day filter training minimum in which the full NVG with facemask and cushion must be worn without spectacles. The NVG system corrects up to +2.00 diopters of hyperopia and up to -6.00 diopters of myopia, but only +/- 1.00 diopter of astigmatism. A survey of the reserve component (USAR and NG) aviators in the Southwest was conducted to establish the relative incompatibility of the NVG system among an aviator population older than the active component aviators. All medical record custodians received questionnaires and the flight surgeon followed up replies by telephone or on-site visits. We screened a total of 127 aviator records. The aviator's average age was 39.5 years; 65.3% had 20/20 vision and were emmetropes. Of those that wore spectacles, 82.4% had hyperopia or myopia correctable by the built-in optical adjustments contained in the NVG. The other 17.6%, who had vision that exceeded the correction factors built into the NVG, consisted of astigmats with greater than 2.00 diopters of cylinder. Nearly 20% of the aviators who wore corrective lenses exceeded the corrective limits of the goggles that they used. Further, pilots had no specific prescreening instruction. With the development of more sophisticated aviation optics. Three options exist: modify visual standards, allow contact lens wear, or design future systems to be compatible with spectacles.

  6. Color vision abnormality as an initial presentation of the complete type of congenital stationary night blindness.

    PubMed

    Tan, Xue; Aoki, Aya; Yanagi, Yasuo

    2013-01-01

    Patients with the complete form of congenital stationary night blindness (CSNB) often have reduced visual acuity, myopia, impaired night vision, and sometimes nystagmus and strabismus, however, they seldom complain of color vision abnormality. A 17-year-old male who was at technical school showed abnormalities in the color perception test for employment, and was referred to our hospital for a detailed examination. He had no family history of color vision deficiency and no other symptoms. During the initial examination, his best-corrected visual acuity was 1.2 in both eyes. His fundus showed no abnormalities except for somewhat yellowish reflex in the fovea of both eyes. Electroretinogram (ERG) showed a good response in cone ERG and 30 Hz flicker ERG, however, the bright flash, mixed rod and cone ERG showed a negative type with a reduced b-wave (positive deflection). There was no response in the rod ERG, either. From the findings of the typical ERG, the patient was diagnosed with complete congenital stationary night blindness. This case underscores the importance of ERG in order to diagnose the cause of a color vision anomaly.

  7. Laboratory assessment of the AN/PVS-5 night vision goggle.

    PubMed

    Chisum, G T; Morway, P E

    1975-11-01

    Laboratory assessment of the AN/PVS-5 Night Vision Goggle was conducted. Visual fields, goggle infrared source, useable range, and detectability of targets with the goggle were measured. Illumination levels of -8.37 and -9.17 log lm/cm2 were adequate for 90% detection of 0.14 and 0.07 acuity targets, respectively. Calculations of distances at which various surface and airborne targets subtended comparable visual angles and tables of natural brightness conditions are presented to permit translation of laboratory values into field conditions. While further field evaluation is anticipated, the laboratory assessment indicates that the goggle can significantly facilitate aircrew night visual performance.

  8. Night vision goggle-induced neck pain in military helicopter aircrew: a literature review.

    PubMed

    Harrison, Michael F; Coffey, Brendan; Albert, Wayne J; Fischer, Steven L

    2015-01-01

    Neck pain occurs at a significant rate in the military helicopter community. It is often attributed to the use of night vision goggles (NVG) and to a number of additional factors such as anthropometrics, posture, vibration, mission length, physical fitness, and helmet fit or load. A number of research studies have addressed many aspects of this epidemic, but an up-to-date and comprehensive review of the literature is not currently available. This paper reviews the spinal anatomy in general and then summarizes what is known about the incidence and prevalence of neck injuries, how the operational environments and equipment may contribute to these injuries, and what can be done to address them from a prevention and/or rehabilitation perspective. Harrison MF, Coffey B, Albert WJ, Fischer SL. Night vision goggle-induced neck pain in military helicopter aircrew: a literature review.

  9. Measurement of night vision goggle (NVG) visual acuity with the NVG resolution chart.

    PubMed

    DeVilbiss, C A; Antonio, J C

    1994-09-01

    Night vision goggles (NVG) operations are characterized as stressful with high task loading. Any reduction in goggle or visual performance which goes undetected can have a serious effect on flight safety and operational capability. The NVG Test Lane, with its resolution chart, provides an effective cost-efficient method for aircrew members to quickly evaluate the correct positioning and focusing of their NVG's prior to each mission. This evaluation validated the ability of the NVG resolution chart to produce the same performance results as a more detailed psychophysical procedure. NVG visual acuity was measured for five subjects (four pilots and one non-pilot) with two different night vision goggles. The results supported that there is no statistical difference between the results obtained with the individual target format and the 3 x 3 format. Additionally, the pilots with current NVG experience were able to obtain a significantly better acuity level than were those without current NVG experience.

  10. Visual fatigue induced by optical misalignment in binocular devices: application to night vision binocular devices

    NASA Astrophysics Data System (ADS)

    Gavrilescu, Maria; Battista, Josephine; Ibbotson, Michael R.; Gibbs, Peter

    2015-05-01

    The additional and perhaps unnatural eye-movements required to fuse misaligned binocular images can lead to visual fatigue and decreased task performance. The eyes have some tolerance to optical misalignment. However, a survey of the scientific literature reveals a wide range of recommended tolerances but offers little supporting experimental evidence. Most experimental studies are based on small numbers of participants exposed to brief periods of optical misalignment. Therefore, these published tolerance limits might have limited relevance for long-duration exposure to misaligned binocular devices. Prolonged use of binocular devices may cause visual fatigue irrespective of binocular alignment especially for complex tasks such as night vision flying. This study attempts to identify measures most sensitive to misalignment in order to establish relevant tolerance limits for in-service binocular night vision devices. Firstly, we developed a rugged and deployable test bench that can measure binocular alignment with a reproducibility error of less than 1 arcmin. The bench was used to identify and investigate major factors affecting the stability of the optical misalignment over time. Our results indicated that the optical misalignment of a given device changed over time as a function of the in-service usage and thermal history of the device. Secondly, participants were exposed to experimentally controlled levels of optical misalignment typical of those measured on in-service binocular night vision devices. The visual fatigue of each participant was assessed via a set of oculomotor parameters. The oculomotor parameters showing high sensitivity to optical misalignment were compared for subjects exposed to extended periods of misalignment in a baseline reading task and a task using an actual night vision device.

  11. Development Test II (Service Phase) of Night Vision Sight, Individual Served Weapons, AN/PVS-4

    DTIC Science & Technology

    1974-11-20

    Reference H reports as a shortcoming that the shipping case liners are not pliable and prevent repacking of the sight in the case at all...the frozen condition, the eyeguard loses weapon-recoil protection. In 8. The insulation of the low-temperature adapter cable cracks and loses its...25 Is the sight an aid to night vision under all conditions, e.g., brush, open terrain, thickly wooded , moonlight, and starlight con- ditions? 3_

  12. Design of refractive/diffractive objective for head-mounted night vision goggle

    NASA Astrophysics Data System (ADS)

    Zhao, Qiu-Ling; Wang, Zhao-Qi; Fu, Ru-Lian; Sun, Qiang; Lu, Zhen-Wu

    A refractive/diffractive objective for head-mounted night vision goggle was designed. This objective consists of six elements, including one binary surface and two hyperboloids. It has a 40[degree sign] field of view, a 1.25 f-number, and a 18 mm image diameter, with a compact structure and a light weight. All optical specifications reach proposed designing targets. Besides, we considered fabrication issues about special surfaces of the system.

  13. G-MAP: a novel night vision system for satellites

    NASA Astrophysics Data System (ADS)

    Miletti, Thomas; Maresi, Luca; Zuccaro Marchi, Alessandro; Pontetti, Giorgia

    2015-10-01

    The recent developments of single-photon counting array detectors opens the door to a novel type of systems that could be used on satellites in low Earth orbit. One possible application is the detection of non-cooperative vessels or illegal fishing activities. Currently only surveillance operations conducted by Navy or coast guard address this topic, operations by nature costly and with limited coverage. This paper aims to describe the architectural design of a system based on a novel single-photon counting detector, which works mainly in the visible and features fast readout, low noise and a 256x256 matrix of 64 μm-pixels. This detector is positioned in the focal plane of a fully aspheric reflective f/6 telescope, to guarantee state of the art performance. The combination of the two grants optimal ground sampling distance, compatible with the average dimension of a vessel, and overall performance. A radiative analysis of the light transmitted from emission to detection is presented, starting from models of lamps used for attracting fishes and illuminating the deck of the boats. A radiative transfer model is used to estimate the amount of photons emitted by such vessels reaching the detector. Since the novel detector features high framerate and low noise, the system as it is envisaged is able to properly serve the proposed goal. The paper shows the results of a trade-off between instrument parameters and spacecraft operations to maximize the detection probability and the covered sea surface. The status of development of both detector and telescope are also described.

  14. Night-time neuronal activation of Cluster N in a day- and night-migrating songbird.

    PubMed

    Zapka, Manuela; Heyers, Dominik; Liedvogel, Miriam; Jarvis, Erich D; Mouritsen, Henrik

    2010-08-01

    Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, and covering up the birds' eyes strongly reduces neuronal activation. These findings suggest that Cluster N processes light-dependent magnetic compass information in night-migrating songbirds. The aim of this study was to test if Cluster N is active during daytime migration. We used behavioural molecular mapping based on ZENK activation to investigate if Cluster N is active in the meadow pipit (Anthus pratensis), a day- and night-migratory species. We found that Cluster N of meadow pipits shows high neuronal activity under dim-light at night, but not under full room-light conditions during the day. These data suggest that, in day- and night-migratory meadow pipits, the light-dependent magnetic compass, which requires an active Cluster N, may only be used during night-time, whereas another magnetosensory mechanism and/or other reference system(s), like the sun or polarized light, may be used as primary orientation cues during the day.

  15. Night-time neuronal activation of Cluster N in a day- and night-migrating songbird

    PubMed Central

    Zapka, Manuela; Heyers, Dominik; Liedvogel, Miriam; Jarvis, Erich D; Mouritsen, Henrik

    2010-01-01

    Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, and covering up the birds’ eyes strongly reduces neuronal activation. These findings suggest that Cluster N processes light-dependent magnetic compass information in night-migrating songbirds. The aim of this study was to test if Cluster N is active during daytime migration. We used behavioural molecular mapping based on ZENK activation to investigate if Cluster N is active in the meadow pipit (Anthus pratensis), a day- and night-migratory species. We found that Cluster N of meadow pipits shows high neuronal activity under dim-light at night, but not under full room-light conditions during the day. These data suggest that, in day- and night-migratory meadow pipits, the light-dependent magnetic compass, which requires an active Cluster N, may only be used during night-time, whereas another magnetosensory mechanism and/or other reference system(s), like the sun or polarized light, may be used as primary orientation cues during the day. PMID:20618826

  16. Multi-capability color night vision HD camera for defense, surveillance, and security

    NASA Astrophysics Data System (ADS)

    Pang, Francis; Powell, Gareth; Fereyre, Pierre

    2015-05-01

    e2v has developed a family of high performance cameras based on our next generation CMOS imagers that provide multiple features and capabilities to meet the range of challenging imaging applications in defense, surveillance, and security markets. Two resolution sizes are available: 1920x1080 with 5.3 μm pixels, and an ultra-low light level version at 1280x1024 with 10μm pixels. Each type is available in either monochrome or e2v's unique bayer pattern color version. The camera is well suited to accommodate many of the high demands for defense, surveillance, and security applications: compact form factor (SWAP+C), color night vision performance (down to 10-2 lux), ruggedized housing, Global Shutter, low read noise (<6e- in Global shutter mode and <2.5e- in Rolling shutter mode), 60 Hz frame rate, high QE especially in the enhanced NIR range (up to 1100nm). Other capabilities include active illumination and range gating. This paper will describe all the features of the sensor and the camera. It will be followed with a presentation of the latest test data with the current developments. Then, it will conclude with a description of how these features can be easily configured to meet many different applications. With this development, we can tune rather than create a full customization, making it more beneficial for many of our customers and their custom applications.

  17. Shortwave infrared for night vision applications: illumination levels and sensor performance

    NASA Astrophysics Data System (ADS)

    Adomeit, Uwe; Krieg, Jürgen

    2015-10-01

    Radiation created by stimulation and recombination/deactivation of atoms and molecules in the higher earth atmosphere is called nightglow. This nightglow can be found in the spectral range from the ultraviolet up to the thermal infrared, with a maximum in the shortwave infrared (SWIR). During moonless nights the illumination in the SWIR is by an order of magnitude higher than the visual one. Within the last years the SWIR sensor technology improved to a level of using the nightglow for night vision applications. This necessitates understanding of the highly variable illumination levels created by the nightglow and the performance assessment of the SWIR detectors in comparison to the image intensifiers respectively Si focal plane array detectors. Whereas the night illumination levels for the visual are standardized, corresponding ones for the SWIR are missing. IOSB started measuring and comparing night illumination levels and camera performance in both spectral ranges based on continuous illumination measurements as well as recording imagery of reflectance reference targets with cameras and analyzing the resulting signal-to-noise ratios. To date the number of illumination measurements are not yet statistically sufficient to standardize the levels, but at least allowed a first comparison of the two technologies for moonless night, clear sky conditions. With comparable F-number, integration time and frame rate, the SWIR sensors available in Europe were found to be inferior to the visual technology. An improvement of at least one magnitude would be necessary to ensure similarity between SWIR and visual technologies for all environmental conditions.

  18. Night vision goggle (NVG) visual acuity under ideal conditions with various adjustment procedures.

    PubMed

    DeVilbiss, C A; Antonio, J C; Fiedler, G M

    1994-08-01

    Night operations involve diverse mission areas and require an increased reliance on the use of night vision devices, such as night vision goggles (NVG's). Any reduction in goggle or visual performance which goes undetected can have a serious effect on flight safety and operational capability. Under controlled lighting conditions, a crewmember should be able to obtain the best possible goggle performance, and to determine if the goggle is functioning properly. These data represent a sample of 218 current USAF aircrew members representing all crew positions in both rotary and fixed-wing aircraft. Three measurements of goggle performance, expressed as NVG visual acuity, were obtained. The first measure, obtained after crewmembers adjusted the goggles with their usual adjustment methods, showed that they routinely obtain less than optimal acuity levels; i.e., averaging between 20/50 and 20/55. The second measure, taken when the NVG Resolution Chart was provided to augment their "usual" method of adjustment, showed improved performance; i.e., averaging 20/45. The third measure, taken following participation in an NVG Adjustment Procedures class, showed the greatest improvement, averaging between 20/35 and 20/40. In summary, it is reasonable to conclude that aircrew members who are able to obtain the best possible performance for their NVG's under controlled preflight conditions will obtain the best possible goggle performance under the widely varying flight conditions.

  19. The effect of test chart design and human factors on visual performance with night vision goggles.

    PubMed

    Silberman, W S; Apsey, D; Ivan, D J; Jackson, W G; Mitchell, G W

    1994-12-01

    In an effort to increase flight safety, it is imperative to learn as much as possible about the man-goggle interrelationship. This study was undertaken to see if type of goggle or other covariates might affect visual acuity (VA). We tested the VA of 103 aircrew with both the AN/PVS-5 and Aviator's Night Vision Imaging System (ANVIS) goggles using a Snellen vision testing chart and the new Night Vision Goggle (NVG) Resolution (Grid Type) Chart. Average VA's using ANVIS (Snellen = 20/38, Grid = 20/45) were significantly better (p < 0.01) than VA's using AN/PVS-5 (Snellen = 20/54, Grid = 20/58). Snellen VA's were better on average than Grid VA's (p < 0.001). Neither age, gender, nor NVG experience affected average VA at the 0.05 level. Average VA was significantly better (p < 0.05) for non-spectacle wearers using ANVIS goggles and for non-smokers using AN/PVS-5 goggles. Visual acuity is better with ANVIS than with AN/PVS-5 goggles, and may be affected somewhat by wearing spectacles, and by smoking.

  20. Improvement of relief algorithm to prevent inpatient's downfall accident with night-vision CCD camera

    NASA Astrophysics Data System (ADS)

    Matsuda, Noriyuki; Yamamoto, Takeshi; Miwa, Masafumi; Nukumi, Shinobu; Mori, Kumiko; Kuinose, Yuko; Maeda, Etuko; Miura, Hirokazu; Taki, Hirokazu; Hori, Satoshi; Abe, Norihiro

    2005-12-01

    "ROSAI" hospital, Wakayama City in Japan, reported that inpatient's bed-downfall is one of the most serious accidents in hospital at night. Many inpatients have been having serious damages from downfall accidents from a bed. To prevent accidents, the hospital tested several sensors in a sickroom to send warning-signal of inpatient's downfall accidents to a nurse. However, it sent too much inadequate wrong warning about inpatients' sleeping situation. To send a nurse useful information, precise automatic detection for an inpatient's sleeping situation is necessary. In this paper, we focus on a clustering-algorithm which evaluates inpatient's situation from multiple angles by several kinds of sensor including night-vision CCD camera. This paper indicates new relief algorithm to improve the weakness about exceptional cases.

  1. A human performance/workload evaluation of the AN/PVS-5 bifocal night vision goggles.

    PubMed

    Stone, L W; Sanders, M G; Glick, D D; Wiley, R W; Kimball, K A

    1980-08-01

    Eight experienced U.S. Army aviators performed various maneuvers in an instrumented helicopter to test the relative usability of two bifocal-configured night vision goggles. Both configurations were statistically better than the unmodified arrangement when looking at a pilot's ability to fly a standard traffic pattern and to hold a precise altitude at night. The subjective data, supported by comparative flight performances with the two bifocals, further suggested that a 24% bifocal version was more desirable than a 14% configuration. The inference is that the reduced inside field of view presented by the 14% bifocal interferes with a pilot's ability to readily locate instruments once he has directed his attention inside the cockpit.

  2. Broad Band Antireflection Coating on Zinc Sulphide Window for Shortwave infrared cum Night Vision System

    NASA Astrophysics Data System (ADS)

    Upadhyaya, A. S.; Bandyopadhyay, P. K.

    2012-11-01

    In state of art technology, integrated devices are widely used or their potential advantages. Common system reduces weight as well as total space covered by its various parts. In the state of art surveillance system integrated SWIR and night vision system used for more accurate identification of object. In this system a common optical window is used, which passes the radiation of both the regions, further both the spectral regions are separated in two channels. ZnS is a good choice for a common window, as it transmit both the region of interest, night vision (650 - 850 nm) as well as SWIR (0.9 - 1.7 μm). In this work a broad band anti reflection coating is developed on ZnS window to enhance the transmission. This seven layer coating is designed using flip flop design method. After getting the final design, some minor refinement is done, using simplex method. SiO2 and TiO2 coating material combination is used for this work. The coating is fabricated by physical vapour deposition process and the materials were evaporated by electron beam gun. Average transmission of both side coated substrate from 660 to 1700 nm is 95%. This coating also acts as contrast enhancement filter for night vision devices, as it reflect the region of 590 - 660 nm. Several trials have been conducted to check the coating repeatability, and it is observed that transmission variation in different trials is not very much and it is under the tolerance limit. The coating also passes environmental test for stability.

  3. Night vision goggle stimulation using LCoS and DLP projection technology, which is better?

    NASA Astrophysics Data System (ADS)

    Ali, Masoud H.; Lyon, Paul; De Meerleer, Peter

    2014-06-01

    High fidelity night-vision training has become important for many of the simulation systems being procured today. The end-users of these simulation-training systems prefer using their actual night-vision goggle (NVG) headsets. This requires that the visual display system stimulate the NVGs in a realistic way. Historically NVG stimulation was done with cathode-ray tube (CRT) projectors. However, this technology became obsolete and in recent years training simulators do NVG stimulation with laser, LCoS and DLP projectors. The LCoS and DLP projection technologies have emerged as the preferred approach for the stimulation of NVGs. Both LCoS and DLP technologies have advantages and disadvantages for stimulating NVGs. LCoS projectors can have more than 5-10 times the contrast capability of DLP projectors. The larger the difference between the projected black level and the brightest object in a scene, the better the NVG stimulation effects can be. This is an advantage of LCoS technology, especially when the proper NVG wavelengths are used. Single-chip DLP projectors, even though they have much reduced contrast compared to LCoS projectors, can use LED illuminators in a sequential red-green-blue fashion to create a projected image. It is straightforward to add an extra infrared (NVG wavelength) LED into this sequential chain of LED illumination. The content of this NVG channel can be independent of the visible scene, which allows effects to be added that can compensate for the lack of contrast inherent in a DLP device. This paper will expand on the differences between LCoS and DLP projectors for stimulating NVGs and summarize the benefits of both in night-vision simulation training systems.

  4. Fabrication and evaluation of chalcogenide glass molding lens for car night-vision system

    NASA Astrophysics Data System (ADS)

    Cha, Du Hwan; Hwang, Yeon; Kim, Jeong-Ho; Kim, Hye-Jeong

    2013-05-01

    With the recent development of less costly uncooled detectors technology, expensive optics are among the remaining significant cost drivers. As a potential solution to this problem, the fabrication of IR lenses using chalcogenide glasses has been studied in recent years. We report on fabrication of molded chalcogenide-glass lens for car night-vision and on the evaluation of the lens. The moldability of chalcogenide glass was characterized through transcription properties of the mold's surface. In addition, both IR transmittance and XRD patterns of the molded chalcogenide glass lens were evaluated to verify the compositional and structural stability of the glass material at the corresponding molding condition.

  5. Development of an aviator's helmet-mounted night-vision goggle system

    NASA Astrophysics Data System (ADS)

    Wilson, Gerry H.; McFarlane, Robert J.

    1990-10-01

    Helmet Mounted Systems (HMS) must be lightweight, balanced and compatible with life support and head protection assemblies. This paper discusses the design of one particular HMS, the GEC Ferranti NITE-OP/NIGHTBIRD aviator's Night Vision Goggle (NVG) developed under contracts to the Ministry of Defence for all three services in the United Kingdom (UK) for Rotary Wing and fast jet aircraft. The existing equipment constraints, safety, human factor and optical performance requirements are discussed before the design solution is presented after consideration of these material and manufacturing options.

  6. Human factors and safety considerations of night-vision systems flight using thermal imaging systems

    NASA Astrophysics Data System (ADS)

    Rash, Clarence E.; Verona, Robert W.; Crowley, John S.

    1990-10-01

    Helmet Mounted Systems (HMS) must be lightweight, balanced and compatible with life support and head protection assemblies. This paper discusses the design of one particular HMS, the GEC Ferranti NITE-OP/NIGHTBIRD aviator's Night Vision Goggle (NVG) developed under contracts to the Ministry of Defence for all three services in the United Kingdom (UK) for Rotary Wing and fast jet aircraft. The existing equipment constraints, safety, human factor and optical performance requirements are discussed before the design solution is presented after consideration of these material and manufacturing options.

  7. Comparison of Topas cyclic olefin copolymers to BK7 glass in night vision goggle objectives

    NASA Astrophysics Data System (ADS)

    Stevens, James S.

    2004-09-01

    The objective of this study was to determine the suitability of Topas cyclic olefin copolymers (COC) as an optical plastic for use in military-grade night vision goggle (NVG) lens objectives. Test objective lenses that could include either a Topas COC window element or BK7 glass window element were manufactured. The test objectives were evaluated for low light resolution, MTF, off-axis veiling glare, and on-axis stray light. Additionally, the spectral transmittance of the individual windows elements was measured. This paper compares the evaluation results of test objectives containing Topas COC with test objectives containing BK7 glass.

  8. Preliminary assessment of night vision goggles in airborne forest fire suppression

    NASA Astrophysics Data System (ADS)

    Jennings, Sion; Craig, Greg; Erdos, Rob; Filiter, Don; Crowell, Bob; Macuda, Todd

    2007-04-01

    Helicopters are widely used in daytime forest fire suppression, conducting diverse tasks such as spotting, re-supply, medical evacuation and airborne delivery. However, they are not used at night for forest fire suppression operations. There would be many challenges when operating in the vicinity of forest fires at night, including scene obscuration from smoke and dynamic changes in lighting conditions. There is little data on the use of Night Vision Goggles (NVGs) for airborne forest fire suppression. The National Research Council of Canada (NRC), in collaboration with the Ontario Ministry of Natural Resources (OMNR), performed a preliminary flight test to examine the use of NVGs while operating near forest fires. The study also simulated limited aspects of night time water bucketing. The preliminary observations from this study suggest that NVGs have potential to improve the safety and efficiency of airborne forest fire suppression, including forest fire perimeter mapping and take-off and landing in the vicinity of open fires. NVG operations at some distance from the fire pose minimal risk to flight, and provide an enhanced capability to identify areas of combustion at greater distances and accuracy. Closer to the fire, NVG flight becomes more risk intensive as a consequence of a reduction in visibility attributable to the adverse effects on NVG performance of the excess radiation and smoke emitted by the fire. The preliminary results of this study suggest that water bucketing at night is a difficult operation with elevated risk. Further research is necessary to clarify the operational limitations and implementation of these devices in forest fire suppression.

  9. Symbology display unit: night vision symbology for the AH-64, increasing mission effectiveness and safety

    NASA Astrophysics Data System (ADS)

    Parise, Michael; McIntire, Dennis

    2006-05-01

    An important capability has been developed for the AH-64 that provides increased mission effectiveness and improved flight safety. First introduced for the Integrated Helmet and Display Sighting Subsystem (IHADSS) on the Agusta A-129, the Symbology Display Unit (SDU) provides IHADSS symbology to the aviator through the Aviator's Night Vision Imaging System (ANVIS) (Night Vision Goggles). Specifically designed for compatibility with the AH-64 and the Legacy IHADSS display and head tracking system, the SDU provides seamless integration of this critical capability into the cockpit. The SDU has been adapted to the IHADSS on the AH-64 and is currently in early fielding within both the US and UK fleets. Although the use of ANVIS on the AH-64 is not a new concept, the ability to display IHADSS symbology integrated with the head tracker is. With the display of IHADSS symbology within the ANVIS field of view, additional capabilities and benefits are realized, including sighting and weapons control, mission performance during poor FLIR conditions, increased target recognition, and improved safety realized by the availability of heads-up pilotage information.

  10. Salient contour extraction from complex natural scene in night vision image

    NASA Astrophysics Data System (ADS)

    Han, Jing; Yue, Jiang; Zhang, Yi; Bai, Lian-fa

    2014-03-01

    The theory of center-surround interaction in non-classical receptive field can be applied in night vision information processing. In this work, an optimized compound receptive field modulation method is proposed to extract salient contour from complex natural scene in low-light-level (LLL) and infrared images. The kernel idea is that multi-feature analysis can recognize the inhomogeneity in modulatory coverage more accurately and that center and surround with the grouping structure satisfying Gestalt rule deserves high connection-probability. Computationally, a multi-feature contrast weighted inhibition model is presented to suppress background and lower mutual inhibition among contour elements; a fuzzy connection facilitation model is proposed to achieve the enhancement of contour response, the connection of discontinuous contour and the further elimination of randomly distributed noise and texture; a multi-scale iterative attention method is designed to accomplish dynamic modulation process and extract contours of targets in multi-size. This work provides a series of biologically motivated computational visual models with high-performance for contour detection from cluttered scene in night vision images.

  11. Detection of motion-defined form under simulated night vision conditions

    NASA Astrophysics Data System (ADS)

    Macuda, Todd; Allison, Robert S.; Thomas, Paul J.; Craig, Gregory; Jennings, Sion

    2004-09-01

    The influence of Night Vision Goggle-produced noise on the perception of motion-defined form was investigated using synthetic imagery and standard psychophysical procedures. Synthetic image sequences incorporating synthetic noise were generated using a software model developed by our research group. This model is based on the physical properties of the Aviator Night Vision Imaging System (ANVIS-9) image intensification tube. The image sequences either depicted a target that moved at a different speed than the background, or only depicted the background. For each trial, subjects were shown a pair of image sequences and required to indicate which sequence contained the target stimulus. We tested subjects at a series of target speeds at several realistic noise levels resulting from varying simulated illumination. The results showed that subjects had increased difficulty detecting the target with increased noise levels, particularly at slower target speeds. This study suggests that the capacity to detect motion-defined form is degraded at low levels of illumination. Our findings are consistent with anecdotal reports of impaired motion perception in NVGs. Perception of motion-defined form is important in operational tasks such as search and rescue and camouflage breaking. These degradations in performance should be considered in operational planning.

  12. An assessment of the ANV 20/20 focusing aid for night vision devices.

    PubMed

    Manton, A G; Webster, K W

    1996-10-01

    Night vision goggles (NVGs) are becoming an increasingly important tool in military aviation. They provide superior visual capability over unaided night vision, but any reduction in goggle performance can have a serious effect on flight safety and operational effectiveness. This study shows that the use of the ANV 20/20 focusing aid provides an effective method for aircrew to obtain a better visual capability than is currently obtained by focusing on distant features of the landscape or distant lights. Visual acuities using the current and proposed focusing methods were compared in 50 aircrew. The visual acuity showed an average improvement of 18% with the proposed method compared with the current method. This was found to be statistically significant (p < 0.01). Using the current method of focusing there was a significant (p < 0.01) difference in the visual acuity achieved between the right and left tubes/eyes. Using the ANV 20/20 there was no difference between tubes/eyes. ANV 20/20 was found to improve visual acuity when using NVG as well as enabling the user to achieve equal visual acuities with both eyes.

  13. Computer-based and web-based applications for night vision goggle training

    NASA Astrophysics Data System (ADS)

    Ruffner, John W.; Woodward, Kim G.

    2001-08-01

    Night vision goggles (NVGs) can enhance military and civilian operations at night. With this increased capability comes the requirement to provide suitable training. Results from field experience and accident analyses suggest that problems experienced by NVG users can be attributed to a limited understanding of NVG limitations and to perceptual problems. In addition, there is evidence that NVG skills are perishable and require frequent practice. Format training is available to help users obtain the required knowledge and skills. However, there often is insufficient opportunity to obtain and practice perceptual skills prior to using NVGs in the operational environment. NVG users need early and continued exposure to the night environment across a broad range of visual and operational conditions to develop and maintain the necessary knowledge and perceptual skills. NVG training has consisted of classroom instruction, hands-on training, and simulator training. Advances in computer-based training (CBT) and web-based training (WBT) have made these technologies very appealing as additions to the NVG training mix. This paper discusses our efforts to develop NVG training using multimedia, interactive CBT and WBT for NVG training. We discuss how NVG CBT and WBT can be extended to military and civilian ground, maritime, and aviation NVG training.

  14. Integration of a Legacy System with Night Vision Training System (NVTS)

    NASA Astrophysics Data System (ADS)

    Anderson, Gretchen M.; Vrana, Craig A.; Riegler, Joseph T.; Martin, Elizabeth L.

    2002-08-01

    The increase in tactical night operations resulted in the requirement for improved night vision goggle (NVG) training and simulation. The Night Vision Training System (NVTS), developed at the Air Force Research Laboratory's Warfighter Training Research Division (AFRL/HEA), provides high-fidelity NVG imagery required to support effective NVG training and mission rehearsal. Acquisition of a multichannel NVTS, to drive both an out-the-window (OTW) view and a helmet-mounted display (HMD), may exceed resources of some training units. An alternative could be to add one channel of NVG imagery to the existing OTW imagery provided by the legacy system. This evaluation addressed engineering and training issues associated with integrating a single NVTS HMD channel with an existing legacy system. Pilots rated the degree of disparity between the HMD and OTW scenes for various scene attributes and effect on flight performance. Findings demonstrated the potential for integration of an NVTS channel with an existing legacy system. Latency and terrain elevation differences between the two databases were measured and did not significantly impact system integration or pilot ratings. When integrating other legacy systems with NVTS, significant disparities may exist between the two databases. Pilot ratings and comments indicate that (a) display brightness and contrast levels of the OTW scene should be set to correspond to real-world, (b) unaided luminance values for a given illumination condition; disparity in moon phase and position between the two sky models should be minimized; and (c) star quantity and brightness in the OTW scene and the NVG scene, as rendered on the HMD, should be as consistent with real-world conditions as possible.

  15. Characterizing night vision goggle noise using the method of paired comparisons

    NASA Astrophysics Data System (ADS)

    Reis, George A.; Marasco, Peter L.; Havig, Paul R.; Heft, Eric L.; Goodyear, Charles D.

    2005-05-01

    Users of night vision goggles (NVGs) have reported differences in NVG noise across different as well as the same type of NVG. To better understand these differences, we attempted to characterize NVG noise by having subjects choose parameters in an NVG simulation to best match the noise in real NVGs. From our previous efforts, we observed interdependence of simulation parameters and variability across observers. This has lead us to use the method of paired comparisons as a process for characterizing NVG noise. The results suggest that people perceive NVG noise differently in terms of spatial, temporal, and contrast combinations. In addition, we provide a methodology for determining psychophysically the best parameter combinations in a simulation"s algorithm to match the real environment that the simulation represents.

  16. Design, development, fabrication, and safety-of-flight testing of a panoramic night vision goggle

    NASA Astrophysics Data System (ADS)

    Jackson, Timothy W.; Craig, Jeffrey L.

    1999-07-01

    A novel approach to significantly increasing the field of view (FOV) of night vision goggles (NVGs) has been developed. This approach uses four image intensifier tubes instead of the usual two to produce a 100 degree wide FOV. A conceptual demonstrator device was fabricated in November 1995 and limited flight evaluations were performed. Further development of this approach continues with eleven advanced technology demonstrators delivered in March 1999 that feature five different design configurations. Some of the units will be earmarked for ejection seat equipped aircraft due to their low profile design allowing the goggle to be retained safely during and after ejection. Other deliverables will be more traditional in design approach and lends itself to transport and helicopter aircraft as well as ground personnel. Extensive safety-of-flight testing has been accomplished as a precursor to the F-15C operational utility evaluation flight testing at Nellis AFB that began in March 1999.

  17. Verification and validation of the night vision goggle tactical decision aid

    NASA Astrophysics Data System (ADS)

    Elrick, John R.

    1995-05-01

    The Night Vision Goggle (NVG) Tactical Decision Aid (TDA) was developed to support Army operations in situations requiring accurate predictions of light levels. Minimum thresholds of illumination are used by the Army to plan and execute missions during periods of darkness or near darkness. The NVG TDA is part of a suite of decision aids that will become part of the fielded Integrated Meteorological System (IMETS). The IMETS is a system designed to be operated by Air Force Staff Weather Officers supporting Army tactical operations in peacetime and in times of conflict. The verification and validation (V & V) effort discussed in this report is part of the Battlefield Environment Directorate configuration management plan to field physically correct and user-friendly software to Army units over the entire conflict spectrum. The V & V described is thorough and shows that the NVG TDA is physically correct and applicable for accreditation before use.

  18. Theoretical and applied aspects of night vision goggle resolution and visual acuity assessment

    NASA Astrophysics Data System (ADS)

    Task, H. Lee; Pinkus, Alan R.

    2007-04-01

    The image quality of night vision goggles is often expressed in terms of visual acuity, resolution or modulation transfer function. The primary reason for providing a measure of image quality is the underlying assumption that the image quality metric correlates with the level of visual performance that one could expect when using the device, for example, target detection or target recognition performance. This paper provides a theoretical analysis of the relationships between these three image quality metrics: visual acuity, resolution and modulation transfer function. Results from laboratory and field studies were used to relate these metrics to visual performance. These results can also be applied to non-image intensifier based imaging systems such as a helmet-mounted display coupled to an imaging sensor.

  19. Psychophysical measurement of night vision goggle noise using a binocular display

    NASA Astrophysics Data System (ADS)

    Reis, George A.; Marasco, Peter L.; Havig, Paul R.; Heft, Eric L.

    2004-09-01

    Users of night vision goggles (NVGs) have reported differences in perceived noise across various NVGs. To understand these differences, we need to measure NVG noise in a psychophysical context. In the precursory study, subjects attempted to characterize NVG noise by examining choices across different parameters of filtered white noise generated on a computer monitor. Subjects adjusted parameters of the filtered noise to match the noise for each combination of two goggles and two luminance levels. Significant differences were found between luminance levels, NVG type, and parameter relationships. Concerns from the previous experiment have yielded this study to better understand if this characterization process has merit. In the previous study, the parameter sequence was constant across trials. We increased the number of trials and subjects, and we included an accounting for parameter sequence. In addition, we used a modified Wheatstone stereoscope to simulate NVG tube independence. We discuss our results in terms of luminance levels, parameter sequence, subject variability, and relationships between parameters.

  20. Night vision goggle visual acuity assessment: results of an interagency test

    NASA Astrophysics Data System (ADS)

    Task, H. Lee

    2001-08-01

    There are several parameters that are used to characterize the quality of a night vision goggle (NVG) such as resolution, gain, field-of-view, visual acuity, etc. One of the primary parameters is visual acuity or resolution of the NVG. These two terms are often used interchangeably primarily because of the measurement methods employed. The objectives of this paper are to present: (1) an argument as to why NVG visual acuity and resolution should be considered as distinctly different parameters, (2) descriptions of different methods of measuring visual acuity and resolution, and (3) the results of a blind test by several agencies to measure the resolution of the same two NVGs (four oculars).

  1. A Field Evaluation of the Compatibility of the Protective Integrated Hood Mask with ANVIS Night Vision Goggles

    DTIC Science & Technology

    1990-07-01

    Mask (PIH11) with the Aviator’s Might Vision Imaging Systems (ANVIS). The PIHM is worn under a standard HGU-55/P helmet and is designed to protect USAF... Image ", Intensifiersl 26 Tran3M133iVitY Visual Acuity 14. PRIC coot Visual Perception ANVIS P1KM ______ 117. SECURITY CLASSIFICATION 18. SECURITY...determine its compatibility with the Aviator’s Night Vision Imaging System (ANVIS). PIHM will be used by tanker, transport, and bomber aircrews for

  2. Enhanced spatial-state feedback for night-vision goggle displays

    NASA Astrophysics Data System (ADS)

    Bachelder, Edward N.; Hansman, R. John, Jr.

    1997-06-01

    A preliminary study was conducted to investigate the use of visual flow cues as an aid to ground and vertical drift awareness during helicopter flight and targeting while using night vision goggles (NVGs). Three displays wee compared: (1) NVG display: simulated NVG image of cockpit and external environment. (2) Overlay display: NVG image with an overlay display but with symbology flow cue field and a surrounding wire-frame globe; (3) Cut-out display: same as the overlay display but with symbology removed from the central region. Three levels of contrast were also compared using each display type. The visual scenery was displayed to subjects using a helmet-mounted virtual reality device that had a 40 by 50 degree field-of-view liquid crystal display. The study involved six pilots. Three tasks were given: (1) Search task: designate enemy targets with a helmet-mounted sight; (2) Hover task: null out all transnational and yaw rates while in a hover; (3) Search/Hover task: perform both Search and Hover tasks simultaneously. These tasks were conducted in a fixed-based helicopter simulator which used the dynamics of a small-scale model helicopter. The following performance measures were collected: (1) Pilot ability to detect and recognize targets; (2) Pilots ability to null transnational and yaw rates; (3) Time scanning the instrument panel. Subjects also rated displays for efficacy in completing the three tasks. Target detection scores conducted during the Search and Search/Hover tasks were highest using the NVG display, followed by the cut-out display. Root-mean-square (RMS) drift rate error was comparable for all display types in the Hover and Hover/Search tasks, however RMS control input activity in all the translational axes was significantly higher in both rate-cueing displays than with the NVG display. From the control input and drift rate time histories it appears that the motion cues were more compelling in the overlay and cut- out displays than those perceived

  3. Night vision imaging system design, integration and verification in spacecraft vacuum thermal test

    NASA Astrophysics Data System (ADS)

    Shang, Yonghong; Wang, Jing; Gong, Zhe; Li, Xiyuan; Pei, Yifei; Bai, Tingzhu; Zhen, Haijing

    2015-08-01

    The purposes of spacecraft vacuum thermal test are to characterize the thermal control systems of the spacecraft and its component in its cruise configuration and to allow for early retirement of risks associated with mission-specific and novel thermal designs. The orbit heat flux is simulating by infrared lamp, infrared cage or electric heater. As infrared cage and electric heater do not emit visible light, or infrared lamp just emits limited visible light test, ordinary camera could not operate due to low luminous density in test. Moreover, some special instruments such as satellite-borne infrared sensors are sensitive to visible light and it couldn't compensate light during test. For improving the ability of fine monitoring on spacecraft and exhibition of test progress in condition of ultra-low luminous density, night vision imaging system is designed and integrated by BISEE. System is consist of high-gain image intensifier ICCD camera, assistant luminance system, glare protect system, thermal control system and computer control system. The multi-frame accumulation target detect technology is adopted for high quality image recognition in captive test. Optical system, mechanical system and electrical system are designed and integrated highly adaptable to vacuum environment. Molybdenum/Polyimide thin film electrical heater controls the temperature of ICCD camera. The results of performance validation test shown that system could operate under vacuum thermal environment of 1.33×10-3Pa vacuum degree and 100K shroud temperature in the space environment simulator, and its working temperature is maintains at 5° during two-day test. The night vision imaging system could obtain video quality of 60lp/mm resolving power.

  4. Sensor fusion to enable next generation low cost Night Vision systems

    NASA Astrophysics Data System (ADS)

    Schweiger, R.; Franz, S.; Löhlein, O.; Ritter, W.; Källhammer, J.-E.; Franks, J.; Krekels, T.

    2010-04-01

    The next generation of automotive Night Vision Enhancement systems offers automatic pedestrian recognition with a performance beyond current Night Vision systems at a lower cost. This will allow high market penetration, covering the luxury as well as compact car segments. Improved performance can be achieved by fusing a Far Infrared (FIR) sensor with a Near Infrared (NIR) sensor. However, fusing with today's FIR systems will be too costly to get a high market penetration. The main cost drivers of the FIR system are its resolution and its sensitivity. Sensor cost is largely determined by sensor die size. Fewer and smaller pixels will reduce die size but also resolution and sensitivity. Sensitivity limits are mainly determined by inclement weather performance. Sensitivity requirements should be matched to the possibilities of low cost FIR optics, especially implications of molding of highly complex optical surfaces. As a FIR sensor specified for fusion can have lower resolution as well as lower sensitivity, fusing FIR and NIR can solve performance and cost problems. To allow compensation of FIR-sensor degradation on the pedestrian detection capabilities, a fusion approach called MultiSensorBoosting is presented that produces a classifier holding highly discriminative sub-pixel features from both sensors at once. The algorithm is applied on data with different resolution and on data obtained from cameras with varying optics to incorporate various sensor sensitivities. As it is not feasible to record representative data with all different sensor configurations, transformation routines on existing high resolution data recorded with high sensitivity cameras are investigated in order to determine the effects of lower resolution and lower sensitivity to the overall detection performance. This paper also gives an overview of the first results showing that a reduction of FIR sensor resolution can be compensated using fusion techniques and a reduction of sensitivity can be

  5. Collaboration between human and nonhuman players in Night Vision Tactical Trainer-Shadow

    NASA Astrophysics Data System (ADS)

    Berglie, Stephen T.; Gallogly, James J.

    2016-05-01

    The Night Vision Tactical Trainer - Shadow (NVTT-S) is a U.S. Army-developed training tool designed to improve critical Manned-Unmanned Teaming (MUMT) communication skills for payload operators in Unmanned Aerial Sensor (UAS) crews. The trainer is composed of several Government Off-The-Shelf (GOTS) simulation components and takes the trainee through a series of escalating engagements using tactically relevant, realistically complex, scenarios involving a variety of manned, unmanned, aerial, and ground-based assets. The trainee is the only human player in the game and he must collaborate, from his web-based mock operating station, with various non-human players via spoken natural language over simulated radio in order to execute the training missions successfully. Non-human players are modeled in two complementary layers - OneSAF provides basic background behaviors for entities while NVTT provides higher level models that control entity actions based on intent extracted from the trainee's spoken natural dialog with game entities. Dialog structure is modeled based on Army standards for communication and verbal protocols. This paper presents an architecture that integrates the U.S. Army's Night Vision Image Generator (NVIG), One Semi- Automated Forces (OneSAF), a flight dynamics model, as well as Commercial Off The Shelf (COTS) speech recognition and text to speech products to effect an environment with sufficient entity counts and fidelity to enable meaningful teaching and reinforcement of critical communication skills. It further demonstrates the model dynamics and synchronization mechanisms employed to execute purpose-built training scenarios, and to achieve ad-hoc collaboration on-the-fly between human and non-human players in the simulated environment.

  6. Distance estimation with night vision goggles: a little feedback goes a long way.

    PubMed

    Niall, K K; Reising, J D; Martin, E L

    1999-09-01

    Immediate feedback was given to correct observers' estimates of distance in an experiment in which those estimates were made outdoors at night while observers wore night vision goggles (NVGs). Initially observers made unguided estimates of distances between marked positions in an open field. Those distances ranged from 7.6 m (25 ft) to 64 m (210 ft). Later the same observers made more estimates. After each of these they were told the measured distance between the positions. During this training, the observers' height from the ground plane was either at a standing position or at an elevated position raised 2.3 m (7 ft 7 in) from standing position. After the training--either immediately after, a week later, or at both times--observers made unguided estimates of distance for a second time. These latter estimates of ground distance made with the NVGs were improved. Average improvement of the observers' estimates persisted for at least one week after training. This training can be applied to improve clearance estimates and estimates of hover height for pilots of rotary-wing aircraft.

  7. Binocular depth acuity research to support the modular multi-spectral stereoscopic night vision goggle

    NASA Astrophysics Data System (ADS)

    Merritt, John O.; CuQlock-Knopp, V. Grayson; Paicopolis, Peter; Smoot, Jennifer; Kregel, Mark; Corona, Bernard

    2006-05-01

    This paper discusses the depth acuity research conducted in support of the development of a Modular Multi-Spectral Stereoscopic (M2S2) night vision goggle (NVG), a customizable goggle that lets the user select one of five goggle configurations: monocular thermal, monocular image intensifier (I2), binocular I2, binocular thermal, and binocular dual-waveband (thermal imagery to one eye and I2 imagery to the other eye). The motives for the development of this type of customizable goggle were (1) the need for an NVG that allows the simultaneous use of two wavebands, (2) the need for an alternative sensor fusion method to avoid the potential image degradation that may accompany digitally fused images, (3) a requirement to provide the observer with stereoscopic, dual spectrum views of a scene, and (4) the need to handle individual user preferences for sensor types and ocular configurations employed in various military operations. Among the increases in functionality that the user will have with this system is the ability to convert from a binocular I2 device (needed for detailed terrain analysis during off-road mobility) to a monocular thermal device (for increased situational awareness in the unaided eye during nights with full moon illumination). Results of the present research revealed potential depth acuity advantages that may apply to off-road terrain hazard detection for the binocular thermal configuration. The results also indicated that additional studies are needed to address ways to minimize binocular incompatibility for the dual waveband configuration.

  8. Flight Testing of Night Vision Systems in Rotorcraft (Test en vol de systemes de vision nocturne a bord des aeronefs a voilure tournante)

    DTIC Science & Technology

    2007-07-01

    Stewart Aerospace Engineering Test Establishment Cold Lake, Alberta CANADA Over thousands of years of evolution humans have developed exceptional...G. (2004). Trial Iguana : A flight evaluation of conformal symbology using display night vision goggles. Paper presented at 30th European Rotorcraft

  9. Switching from forward-looking infrared to night vision goggles: transitory effects on visual resolution.

    PubMed

    Rabin, J; Wiley, R

    1994-04-01

    Helmet-mounted displays under development for rotary- and fixed-wing aircraft will allow the user to switch electronically between forward-looking infrared (FLIR) and night vision goggle (NVG) sensors. These sensor transitions potentially involve large changes in display luminance which could transiently impair visual resolution and performance. The purpose of this study was to identify the display luminances which produce a transient reduction in vision when switching from a higher luminance (i.e., FLIR) to a lower luminance (i.e., NVG) display. A letter recognition task was used to assess the effect of luminance adaptation on visual resolution in five subjects. A significant reduction in letter recognition was observed in the first second after switching from simulated FLIR to simulated NVG's when the FLIR luminance was > or = 10 fL. By varying letter size, contrast, and exposure time, the magnitude and duration of visual loss after switching from a bright (49.2 fL) FLIR display were determined. The visual loss lasted up to 4 s, and included a 2x reduction in visual acuity, and a 3x reduction in contrast sensitivity. Large differences in sensor display luminance should be avoided to maintain high levels of visual performance and aviation safety. Design features or training may be necessary to achieve a proper balance between FLIR and NVG luminances which optimize performance and safety without sacrificing the quality of the sensor image.

  10. Resolution and signal-to-noise measurement of U.S. Army night-vision goggles

    NASA Astrophysics Data System (ADS)

    Rivamonte, Lorenzo A.

    1990-10-01

    The ability to quantitatively characterize the performance of night vision goggles (NVG) is being investigated because the present method of resolution evaluation relies on an imprecise, subjective pass/fail judgement by a trained observer viewing a test pattern. Variation in an observer's training, experience, psychological state, decision bias and visual acuity strongly affect his or her decision when required to decide if a marginal pair of goggles passes or fails. The controversy concerning the increase in commercial and military helicopter accidents involving NVG indicates a need to determine if 1) the use of defective or marginal NVG is a contributing factor to the increase in accidents or 2) the apparent correlation between NVG and accidents is simply due to the increased use of NVG in an expanded and inherently more dangerous flight envelope. The U.S. Army TMDE Support Group (USATSG) has developed instrumentation to augment the AN/3895 TS test set that presents high and low light level resolution targets to AN/PVS-5, AN/AVS-6 and AN/PVS-7 NVG. The NVG Resolution Augmentation to the AN/3895 TS presented here can also quantitatively measure image quality of other image producing systems which are normally viewed, adjusted or inspected by a human observer. The NVG Resolution Augmentation features a custom electronic circuit which provides a user-friendly interface between a commercially available CCD camera, monitor and oscilloscope. USATSG's Army Primary Standards Laboratory at the Redstone Arsenal is presently studying the possibility of a new measurement service by investigating various CCD camera/lens combinations in order to characterize a machine vision standard observer. A characterized image analysis system would enable absolute as well as relative measurements of image quality.

  11. Automated and semi-automated field testing of night vision goggles

    NASA Astrophysics Data System (ADS)

    Scopatz, Stephen; Paszkeicz, Dominic; Langsdorf, Brent

    2016-05-01

    This paper will discuss the development and results of a new field portable test set for Gen 2 and Gen 3 night vision goggles that automates many of the tests supported by currently available NVG test products. The major innovation is the use of MTF testing with a knife edge target. MTF testing is established in the laboratory environment and well suited to replace the operator's interpretation of the USAF 1951 resolution chart. Results will be presented to show the more consistent performance of the MTF approach as compared to the known operator variations when humans determine resolution. Other standard tests are semi-automated and/or video-assisted, such as infinity focus, spot defects, and distortion. The presentation will show repeatability across test units and operators on the key tests. The presentation will include automatically generated examples of the report files for each test run on each goggle. All of these capabilities are provided in a package that matches the form factor of other products in use to test NVG's. A discussion of the user interface and the ease of use of the system will be included as well as the improvement in the test time for each goggle type.

  12. Effect of night vision goggles on performance of advanced life support skills by emergency personnel.

    PubMed

    Brummer, Savoy; Dickinson, Edward T; Shofer, Frances S; McCans, James P; Mechem, C Crawford

    2006-04-01

    Night vision goggles (NVGs) are used by military personnel operating in low-light environments. It is not known whether NVGs can be used by medical personnel to provide emergency care under such conditions. This was a randomized controlled study to determine the effect of NVGs on the performance of intravenous line insertion (IVI) and endotracheal intubation (El) on training manikins. Emergency physicians and paramedics were randomized to perform EI and IVI in ambient light or in total darkness using NVGs. Each skill was repeated three times, and averages were determined. The average times for EI in ambient light and with NVGs were 48.4 and 188.2 seconds, respectively (SE of 13.4 seconds for both; p < 0.0001). The average times for IVI in ambient light and with NVGs were 34.7 and 73.7 seconds, respectively (SE of 4.1 seconds for both; p < 0.0001). Emergency personnel were able to successfully perform these skills using NVGs, but their times were significantly longer than in ambient light.

  13. Physical modeling and characterization of the halo phenomenon in night vision goggles

    NASA Astrophysics Data System (ADS)

    Thomas, Paul J.; Allison, Robert S.; Carr, Peter; Shen, Edward; Jennings, Sion; Macuda, Todd; Craig, Greg; Hornsey, Richard

    2005-05-01

    When a bright light source is viewed through Night Vision Goggles (NVG), the image of the source can appear enveloped in a "halo" that is much larger than the "weak-signal" point spread function of the NVG. The halo phenomenon was investigated in order to produce an accurate model of NVG performance for use in psychophysical experiments. Halos were created and measured under controlled laboratory conditions using representative Generation III NVGs. To quantitatively measure halo characteristics, the NVG eyepiece was replaced by a CMOS imager. Halo size and intensity were determined from camera images as functions of point-source intensity and ambient scene illumination. Halo images were captured over a wide range of source radiances (7 orders of magnitude) and then processed with standard analysis tools to yield spot characteristics. The spot characteristics were analyzed to verify our proposed parametric model of NVG halo event formation. The model considered the potential effects of many subsystems of the NVG in the generation of halo: objective lens, photocathode, image intensifier, fluorescent screen and image guide. A description of the halo effects and the model parameters are contained in this work, along with a qualitative rationale for some of the parameter choices.

  14. Night Vision And Electro-Optics Laboratory (NVEOL) Performance Model And Its Use

    NASA Astrophysics Data System (ADS)

    Hoover, C.; Ratches, J.; Shields, F.; Mayo, K.

    1982-06-01

    This paper discusses the major design tools utilized at the Night Vision and Electro-Optics Laboratory (NVEOL) for analyzing electro-optical sensor systems. The Thermal Static Performance Model is described as an example of the methods used. The other systems models are based on the same concepts both in analysis and computer programming. The basic approach for all the laboratory and field models is tied to measurement techniques. The models provide a set of tools to write specifications, design systems and analyze requirements. The basic thermal model code, its use, and limitations will be explained. The current version utilized at NVEOL makes use of an interactive input data structure, and includes a graphics package for field performance. Similiar models exist for image intensifiers (II), television (TV), and aided/unaided eye. These models however are not as widely used and therefore have not received the same level of resources as the thermal models. All of these models enable one to predict performance against a variety of target configurations and atmospheric conditions including smoke. The use of the computer programs is illustra-ted.

  15. Aircrew visual acuity viewing with different night vision goggle eyepiece diopter settings

    NASA Astrophysics Data System (ADS)

    Angel, Share-Dawn P.; Baldwin, J. Bruce

    2004-09-01

    The AN/AVS-9 night vision goggle (NVG) has an eyepiece lens that can be adjusted from +2 to -6 diopters (D). We have shown previously1,2,3 that on average NVG users tend to select about -1D, with a range of +0.5D to -4D3. This study was designed to evaluate NVG visual acuity (NVG VA) and subjective ratings for a range of diopter settings including user-selected and three fixed settings of -0.25D, -1D and -2D. Twenty-one experienced USAF Special Operations aircrew members, including 15 pilots, served as subjects. The median user-selected setting was -1.25D and ranged from +0.5D to -3.5D. Only 2 of the 21 subjects had user-selected NVG VA significantly better than a fixed setting of -1D. Of those two, one was not wearing prescribed glasses and the other was 49 years old, presbyopic, and could not focus through the -1D lenses. Subjective ratings and NVG VA indicated that most people could fly with a fixed setting of -1D for each eye, although two individuals needed different diopter settings for the right and left eyes. The new Panoramic NVG (PNVG) has a fixed eyepiece focus of -1D. Results suggest the PNVG should have a limited set of accessory lenses available.

  16. Effects of saturation contrast on color recognition in night vision goggles

    NASA Astrophysics Data System (ADS)

    Havig, Paul R.; Marasco, Peter L.; Post, David L.; Ellwanger, Harold L.; Reis, George A.

    2004-09-01

    In the past we have examined the luminance contrast ratios required to maintain color recognition in helmet-mounted displays (HMDs). Using typical daytime viewing conditions as simulated backgrounds we were able to determine 95% correct color recognition thresholds resulting in luminance contrast ratios averaging 1.17:1. Last year we adapted this research to determine the best colors to maintain color recognition of symbology that is on a night vision goggle (NVG) image. We simulated NVG P43 green phosphor and determined 95% correct color recognition thresholds. Results indicated that, on average, a luminance contrast ratio of nearly 1.5:1 was required to maintain color recognition. Review of the studies indicated that our simulated P43 phosphor was a much more saturated background, so saturation contrast may play as important a role as luminance contrast. A P45 white phosphor NVG may therefore be less problematic. Here we investigate the effects of both luminance and saturation contrast by manipulating color mixtures of green, yellow, and red symbology against two different backgrounds, P43 green and P45 white. We discuss our results in terms of both luminance and saturation contrast required for the maintenance of color recognition in NVGs.

  17. NIST traceable measurements of radiance and luminance levels of night-vision-goggle test-instruments

    NASA Astrophysics Data System (ADS)

    Eppeldauer, G. P.; Podobedov, V. B.

    2014-05-01

    In order to perform radiance and luminance level measurements of night-vision-goggle (NVG) test instruments, NIST developed new-generation transfer-standard radiometers (TR). The new TRs can perform low-level radiance and luminance measurements with SI traceability and low uncertainty. The TRs were calibrated against NIST detector/radiometer standards holding the NIST photometric and radiometric scales. An 815 nm diode laser was used at NIST for the radiance responsivity calibrations. A spectrally flat (constant) filter correction was made for the TRs to correct the spectral responsivity change of the built-in Si photodiode for LEDs peaking at different wavelengths in the different test sets. The radiance responsivity transfer to the test instruments (test-sets) is discussed. The radiance values of the test instruments were measured with the TRs. The TRs propagate the traceablity to the NIST detector-based reference scales. The radiance uncertainty obtained from three TR measurements was 4.6 % (𝑘=2) at a luminance of 3.43 x 10-4 cd/m2. The output radiance of the previously used IR sphere source and the radiance responsivity of a previously used secondary standard detector unit, which was originally calibrated against an IR sphere source, were also measured with the TRs. The performances of the NVG test instruments were evaluated and the manufacturer produced radiance and luminance levels were calibrated with SI/NIST traceability.

  18. A Comparison of the AVS-9 and the Panoramic Night Vision Goggle During Rotorcraft Hover and Landing

    NASA Technical Reports Server (NTRS)

    Szoboszlay, Zoltan; Haworth, Loran; Simpson, Carol; Rutkowski, Michael (Technical Monitor)

    2001-01-01

    The purpose of this flight test was to measure any differences in pilot-vehicle performance and pilot opinion between the use of the current generation AVS-9 Night Vision Goggle and one variant of the prototype Panoramic Night Vision Goggle (the PNV.GII). The PNVGII has more than double the horizontal field-of-view of the AVS-9, but reduced image quality. The flight path of the AH-1S helicopter was used as a measure of pilot-vehicle performance. Also recorded were subjective measures of flying qualities, physical reserves of the pilot, situational awareness, and display usability. Pilot comment and data indicate that the benefits of additional FOV with the PNVGIIs are to some extent negated by the reduced image quality of the PNVGIIs.

  19. A Comparison of the AVS-9 and the Panoramic Night Vision Goggles During Rotorcraft Hover and Landing

    NASA Technical Reports Server (NTRS)

    Szoboszlay, Zoltan; Haworth, Loran; Simpson, Carol

    2000-01-01

    A flight test was conducted to assess any differences in pilot-vehicle performance and pilot opinion between the use of a current generation night vision goggle (the AVS-9) and one variant of the prototype panoramic night vision goggle (the PNVGII). The panoramic goggle has more than double the horizontal field-of-view of the AVS-9, but reduced image quality. Overall the panoramic goggles compared well to the AVS-9 goggles. However, pilot comment and data are consistent with the assertion that some of the benefits of additional field-of-view with the panoramic goggles were negated by the reduced image quality of the particular variant of the panoramic goggles tested.

  20. Cav1.4 IT mouse as model for vision impairment in human congenital stationary night blindness type 2.

    PubMed

    Knoflach, Dagmar; Kerov, Vasily; Sartori, Simone B; Obermair, Gerald J; Schmuckermair, Claudia; Liu, Xiaoni; Sothilingam, Vithiyanjali; Garcia Garrido, Marina; Baker, Sheila A; Glösmann, Martin; Schicker, Klaus; Seeliger, Mathias; Lee, Amy; Koschak, Alexandra

    2013-01-01

    Mutations in the CACNA1F gene encoding the Cav1.4 Ca (2+) channel are associated with X-linked congenital stationary night blindness type 2 (CSNB2). Despite the increasing knowledge about the functional behavior of mutated channels in heterologous systems, the pathophysiological mechanisms that result in vision impairment remain to be elucidated. This work provides a thorough functional characterization of the novel IT mouse line that harbors the gain-of-function mutation I745T reported in a New Zealand CSNB2 family. (1) Electroretinographic recordings in IT mice permitted a direct comparison with human data. Our data supported the hypothesis that a hyperpolarizing shift in the voltage-dependence of channel activation-as seen in the IT gain-of-function mutant (2)-may reduce the dynamic range of photoreceptor activity. Morphologically, the retinal outer nuclear layer in adult IT mutants was reduced in size and cone outer segments appeared shorter. The organization of the outer plexiform layer was disrupted, and synaptic structures of photoreceptors had a variable, partly immature, appearance. The associated visual deficiency was substantiated in behavioral paradigms. The IT mouse line serves as a specific model for the functional phenotype of human CSNB2 patients with gain-of-function mutations and may help to further understand the dysfunction in CSNB.

  1. A channel-based color fusion technique using multispectral images for night vision enhancement

    NASA Astrophysics Data System (ADS)

    Zheng, Yufeng

    2011-09-01

    A fused image using multispectral images can increase the reliability of interpretation because it combines the complimentary information apparent in multispectral images. While a color image can be easily interpreted by human users (for visual analysis), and thus improves observer performance and reaction times. We propose a fast color fusion method, termed as channel-based color fusion, which is efficient for real time applications. Notice that the term of "color fusion" means combing multispectral images into a color-version image with the purpose of resembling natural scenes. On the other hand, false coloring technique usually has no intention of resembling natural scenery. The framework of channel-based color fusion is as follows, (1) prepare for color fusion by preprocessing, image registration and fusion; (2) form a color fusion image by properly assigning multispectral images to red, green, and blue channels; (3) fuse multispectral images (gray fusion) using a wavelet-based fusion algorithm; and (4) replace the value component of color fusion in HSV color space with the gray-fusion image, and finally transform back to RGB space. In night vision imaging, there may be two or several bands of images available, for example, visible (RGB), image intensified (II), near infrared (NIR), medium wave infrared (MWIR), long wave infrared (LWIR). The proposed channel-wise color fusions were tested with two-band (e.g., NIR + LWIR, II + LWIR, RGB + LWIR) or three-band (e.g., RGB + NIR + LWIR) multispectral images. Experimental results show that the colors in the fused images by the proposed method are vivid and comparable with that of the segmentation-based colorization. The processing speed of new method is much faster than any segmentation-based method.

  2. Qualitative evaluations and comparisons of six night-vision colorization methods

    NASA Astrophysics Data System (ADS)

    Zheng, Yufeng; Reese, Kristopher; Blasch, Erik; McManamon, Paul

    2013-05-01

    Current multispectral night vision (NV) colorization techniques can manipulate images to produce colorized images that closely resemble natural scenes. The colorized NV images can enhance human perception by improving observer object classification and reaction times especially for low light conditions. This paper focuses on the qualitative (subjective) evaluations and comparisons of six NV colorization methods. The multispectral images include visible (Red-Green- Blue), near infrared (NIR), and long wave infrared (LWIR) images. The six colorization methods are channel-based color fusion (CBCF), statistic matching (SM), histogram matching (HM), joint-histogram matching (JHM), statistic matching then joint-histogram matching (SM-JHM), and the lookup table (LUT). Four categries of quality measurements are used for the qualitative evaluations, which are contrast, detail, colorfulness, and overall quality. The score of each measurement is rated from 1 to 3 scale to represent low, average, and high quality, respectively. Specifically, high contrast (of rated score 3) means an adequate level of brightness and contrast. The high detail represents high clarity of detailed contents while maintaining low artifacts. The high colorfulness preserves more natural colors (i.e., closely resembles the daylight image). Overall quality is determined from the NV image compared to the reference image. Nine sets of multispectral NV images were used in our experiments. For each set, the six colorized NV images (produced from NIR and LWIR images) are concurrently presented to users along with the reference color (RGB) image (taken at daytime). A total of 67 subjects passed a screening test ("Ishihara Color Blindness Test") and were asked to evaluate the 9-set colorized images. The experimental results showed the quality order of colorization methods from the best to the worst: CBCF < SM < SM-JHM < LUT < JHM < HM. It is anticipated that this work will provide a benchmark for NV

  3. Evaluation of integrated night vision goggle (NVG) helmets under sustained +Gz.

    PubMed

    McCloskey, K; Esken, R L

    1995-02-01

    Three integrated night vision goggle (NVG) helmets from different manufacturers were evaluated under high-G conditions. Structural and operational integrity, as well as neck forces in pounds, were determined via instrumented manikin testing before human exposure with the helmets during sustained +Gz. Results of the manikin testing showed that the helmets could withstand the rigors of high-G, and that predicted forces (using helmet weights and centers-of-gravity) matched those obtained experimentally from load cells in the x-axis of the manikin's neck. After manikin testing, 10 subjects were randomly exposed to four different high-G profiles on the Dynamic Environmental Simulator (DES) man-rated centrifuge located at Wright-Patterson AFB, OH: gradual onset to +8 Gz, a simulated aerial combat maneuver (SACM) profile, and two +4 Gz profiles, one with the mask dangling from the helmet and the other with the mask removed. Fit assessments were conducted before high-G exposure, and one helmet was affected significantly by failure of fit. The degree of migration of the NVG intensified image away from the eyes was affected most by the following helmet characteristics: design of the nape strap, size of the NVG image provided by each helmet system, goodness of helmet fit, and the use of the mask as a stabilizer. Although neck strength of each subject was measured and compared to the degree of head stability while wearing each helmet, no effects were found. However, subjects were not allowed to perform fast, high-amplitude head movements in the centrifuge for safety reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Cav1.4 IT mouse as model for vision impairment in human congenital stationary night blindness type 2

    PubMed Central

    Knoflach, Dagmar; Kerov, Vasily; Sartori, Simone B; Obermair, Gerald J; Schmuckermair, Claudia; Liu, Xiaoni; Sothilingam, Vithiyanjali; Garrido, Marina Garcia; Baker, Sheila A; Glösmann, Martin; Schicker, Klaus; Seeliger, Mathias; Lee, Amy; Koschak, Alexandra

    2013-01-01

    Mutations in the CACNA1F gene encoding the Cav1.4 Ca2+ channel are associated with X-linked congenital stationary night blindness type 2 (CSNB2). Despite the increasing knowledge about the functional behavior of mutated channels in heterologous systems, the pathophysiological mechanisms that result in vision impairment remain to be elucidated. This work provides a thorough functional characterization of the novel IT mouse line that harbors the gain-of-function mutation I745T reported in a New Zealand CSNB2 family.1 Electroretinographic recordings in IT mice permitted a direct comparison with human data. Our data supported the hypothesis that a hyperpolarizing shift in the voltage-dependence of channel activation—as seen in the IT gain-of-function mutant2—may reduce the dynamic range of photoreceptor activity. Morphologically, the retinal outer nuclear layer in adult IT mutants was reduced in size and cone outer segments appeared shorter. The organization of the outer plexiform layer was disrupted, and synaptic structures of photoreceptors had a variable, partly immature, appearance. The associated visual deficiency was substantiated in behavioral paradigms. The IT mouse line serves as a specific model for the functional phenotype of human CSNB2 patients with gain-of-function mutations and may help to further understand the dysfunction in CSNB. PMID:24051672

  5. Establishing Mobility Measures to Assess the Effectiveness of Night Vision Devices: Results of a Pilot Study

    ERIC Educational Resources Information Center

    Zebehazy, Kim T.; Zimmerman, George J.; Bowers, Alex R.; Luo, Gang; Peli, Eli

    2005-01-01

    In addition to their restricted peripheral fields, persons with retinitis pigmentosa (RP) report significant problems seeing in low levels of illumination, which causes difficulty with night travel. Several devices have been developed to support the visual needs of persons who have night blindness. These devices include wide-angle flashlights,…

  6. Advanced Image Intensifier: a 60°field-of-view night vision system with integral electroluminescent display

    NASA Astrophysics Data System (ADS)

    Crenshaw, David A.; Branigan, Robert G.

    1996-06-01

    The Advanced Image Intensifier Advanced Technology Demonstrator is an Army program to develop and demonstrate the next generation of night vision goggle using revolutionary new technologies to improve system performance and expand the capability of currently fielded image intensifier devices. The Advanced Image Intensifier is a helmet mounted imaging and display system that exploits recent advances in diffractive optics, miniature flat panel displays, image intensifier tube technology and manufacturing processes. The system will demonstrate significantly enhanced operational performance by increasing low-light resolution by greater than 25 percent; increasing field of view from 40 degrees to 60 degrees; improving high light performance; and integrating a display for viewing thermal imagery, computer graphics, and symbology. The results of these improvements will increase the night fighting capability, operational effectiveness, mobilty, versatility, and survivability of the dismounted soldier and aviator.

  7. Improving nighttime mobility in persons with night blindness caused by retinitis pigmentosa: A comparison of two low-vision mobility devices.

    PubMed

    Mancil, Rickilyn M; Mancil, Gary L; King, Ellis; Legault, Claudine; Munday, Julie; Alfieri, Salvatore; Nowakowski, Rod; Blasch, Bruce B

    2005-01-01

    This study compared the effectiveness of the ITT Night Vision Viewer with the Wide Angle Mobility Lamp (WAML) as low-vision mobility devices for people experiencing night blindness due to retinitis pigmentosa (RP). Both engineering bench testing and functional evaluations were used in the assessments. Engineering evaluations were conducted for (1) consistency of the manufacturer's specifications, (2) ergonomic characteristics, (3) modifications of devices, and (4) pedestrian safety issues. Twenty-seven patients with RP conducted rehabilitation evaluations with each device that included both clinical and functional tests. Both devices improved nighttime travel for people with night blindness as compared with nighttime travel with no device. Overall, the WAML provided better travel efficiency-equivalent to that measured in daytime. Recommendations have been developed on ergonomic factors for both devices. Although some participants preferred the ITT Night Vision Viewer, overall most participants performed better with the WAML.

  8. The effects of moon illumination, moon angle, cloud cover, and sky glow on night vision goggle flight performance

    NASA Astrophysics Data System (ADS)

    Loro, Stephen Lee

    This study was designed to examine moon illumination, moon angle, cloud cover, sky glow, and Night Vision Goggle (NVG) flight performance to determine possible effects. The research was a causal-comparative design. The sample consisted of 194 Fort Rucker Initial Entry Rotary Wing NVG flight students being observed by 69 NVG Instructor Pilots. The students participated in NVG flight training from September 1992 through January 1993. Data were collected using a questionnaire. Observations were analyzed using a Kruskal-Wallis one-way analysis of variance and a Wilcox matched pairs signed-ranks test for difference. Correlations were analyzed using Pearson's r. The analyses results indicated that performance at high moon illumination levels is superior to zero moon illumination, and in most task maneuvers, superior to >0%--50% moon illumination. No differences were found in performance at moon illumination levels above 50%. Moon angle had no effect on night vision goggle flight performance. Cloud cover and sky glow have selective effects on different maneuvers. For most task maneuvers, cloud cover does not affect performance. Overcast cloud cover had a significant effect on seven of the 14 task maneuvers. Sky glow did not affect eight out of 14 task maneuvers at any level of sky glow.

  9. Detection of pedestrians in far-infrared automotive night vision using region-growing and clothing distortion compensation

    NASA Astrophysics Data System (ADS)

    O'Malley, Ronan; Jones, Edward; Glavin, Martin

    2010-11-01

    We present a night-time pedestrian detection system based on automotive infrared video processing. Far-infrared or thermal night vision is a technology well suited for automatic detection of pedestrians at night as they generally appear warmer than the background. However, the appearance of a pedestrian in IR video can vary dramatically depending on the physical properties of the clothing they wear, the time spent adjusting to the outside environment, and the ambient temperature. We highlight the difficulties of detection in low temperatures (below 8 °C) when pedestrians typically wear highly insulating clothing, which can lead to distortion of the IR signature of the pedestrian. A pre-processing step is presented, which compensates for this clothing-based distortion using vertically-biased morphological closing. Potential pedestrians (Regions of Interest) are then segmented using feature-based region-growing with high intensity seeds. Histogram of Oriented Gradients (HOG) features are extracted from candidates and utilised for Support Vector Machine classification. Positively classified targets are tracked between frames using a Kalman filter, adding robustness and increasing performance. The proposed system adapts not just to variations between images or video frames, but to variations in appearance between different pedestrians in the same image or frame. Results indicate improved performance compared to previous HOG-SVM automotive IR pedestrian detection systems, which utilised stereo IR cameras.

  10. Müller cells separate between wavelengths to improve day vision with minimal effect upon night vision

    NASA Astrophysics Data System (ADS)

    Labin, Amichai M.; Safuri, Shadi K.; Ribak, Erez N.; Perlman, Ido

    2014-07-01

    Vision starts with the absorption of light by the retinal photoreceptors—cones and rods. However, due to the ‘inverted’ structure of the retina, the incident light must propagate through reflecting and scattering cellular layers before reaching the photoreceptors. It has been recently suggested that Müller cells function as optical fibres in the retina, transferring light illuminating the retinal surface onto the cone photoreceptors. Here we show that Müller cells are wavelength-dependent wave-guides, concentrating the green-red part of the visible spectrum onto cones and allowing the blue-purple part to leak onto nearby rods. This phenomenon is observed in the isolated retina and explained by a computational model, for the guinea pig and the human parafoveal retina. Therefore, light propagation by Müller cells through the retina can be considered as an integral part of the first step in the visual process, increasing photon absorption by cones while minimally affecting rod-mediated vision.

  11. Critique of "distance estimation with night vision goggles: a little feedback goes a long way"

    PubMed

    DeLucia

    1999-09-01

    The authors addressed a topic that has practical importance and that deserves further study. They raised interesting questions about distance estimates, and extended results obtained with unaided vision to performance with NVGs. In this critique, several issues were raised in an attempt to foster an informative scholarly exchange.

  12. Visual Problems in Night Operations (Problemes de Vision dans les Operations de Nuit)

    DTIC Science & Technology

    1992-05-01

    jours couramment utilises. Lors du dernier conflit elles ont 6t6 a la base de la r~ussite de missions spectaculaires. 11 faut bien evidemment differencier...simple conflit perceptif. University press KOSSLYN S. (1975) Information representation in visual 4-CONCLUSION images: Some structural implications...avions sont au centre do l’utilisation do systbmes multi-senseurs qui prtsentent tin risque do conflit . de suppldance I la vision nocturne. Une longue

  13. Visual performance with night vision goggles (NVGs) measured in U.S. Air Force aircrew members

    NASA Astrophysics Data System (ADS)

    DeVilbiss, Carita A.; Ercoline, William R.; Antonio, Joseph C.

    1994-06-01

    Since vision is by far the most important sensory input for spatial orientation, it is important to obtain the best visual performance possible from any device. To determine whether current devices were being properly adjusted, visual performance data were obtained from USAF NVG aircrew members after they (1) adjusted the goggle using their usual method of adjustment, (2) used the NVG resolution chart to augment their usual method, and (3) used goggle-adjustment procedures learned in the training class. Results show that without a standard target or procedures, aircrew members were not able to obtain optimal goggle performance - the average visual performance was 20/53 for the 218 aviators in this study. For the 158 aviators who also used the standard target with their usual procedure, there was a significant improvement (average of 20/47). Finally, significantly better goggle performance (average of 20/37) was obtained when 48 aviators adjusted their goggles using procedures learned in the adjustment training class. While these data support the importance of preflight adjustment of NVGs, they represent visual performance under optimal, controlled conditions. It is important to remember that visual performance under actual flight conditions can be significantly impaired with reduced illumination, low contrast levels, improper cockpit lighting, and poor transmissivity of infrared energy through the transparencies.

  14. Coevolution of active vision and feature selection.

    PubMed

    Floreano, Dario; Kato, Toshifumi; Marocco, Davide; Sauser, Eric

    2004-03-01

    We show that complex visual tasks, such as position- and size-invariant shape recognition and navigation in the environment, can be tackled with simple architectures generated by a coevolutionary process of active vision and feature selection. Behavioral machines equipped with primitive vision systems and direct pathways between visual and motor neurons are evolved while they freely interact with their environments. We describe the application of this methodology in three sets of experiments, namely, shape discrimination, car driving, and robot navigation. We show that these systems develop sensitivity to a number of oriented, retinotopic, visual-feature-oriented edges, corners, height, and a behavioral repertoire to locate, bring, and keep these features in sensitive regions of the vision system, resembling strategies observed in simple insects.

  15. Comparison of three night vision intensification tube technologies on resolution acuity: results from grating and Hoffman ANV-126 tasks

    NASA Astrophysics Data System (ADS)

    Macuda, Todd; Allison, Robert S.; Thomas, Paul; Truong, Long; Tang, Denis; Craig, Greg; Jennings, Sion

    2005-05-01

    Several methodologies have been used to determine resolution acuity through Night Vision Goggles. The present study compared NVG acuity estimates derived from the Hoffman ANV-126 and a standard psychophysical grating acuity task. For the grating acuity task, observers were required to discriminate between horizontal and vertical gratings according to a method of constant stimuli. Psychometric functions were generated from the performance data, and acuity thresholds were interpolated at a performance level of 70% correct. Acuity estimates were established at three different illumination levels (0.06-5X10-4 lux) for both procedures. These estimates were then converted to an equivalent Snellen value. The data indicate that grating acuity estimates were consistently better (i.e. lower scores) than acuity measures obtained from the Hoffman ANV-126. Furthermore significant differences in estimated acuity were observed using different tube technologies. In keeping with previous acuity investigations, although the Hoffman ANV-126 provides a rapid operational assessment of tube acuity, it is suggested that more rigorous psychophysical procedures such as the grating task described here be used to assess the real behavioural resolution of tube technologies.

  16. Aural-Nondetectability Model Predictions for Night-Vision Goggles across Ambient Lighting Conditions

    DTIC Science & Technology

    2015-12-01

    approximate starlight, half- moon , and room light. All of these devices operate in a linear mode under low-light conditions (no active gating to limit...mid, half- moon ; and 3) high, room light. Although the absolute luminance approximated the specified lighting conditions, the spectra from the light...Radiative addition (W/m2) Photopic only Photopic+infrared Starlight LED 3.93E-06 6.19E-08 1.23E-07 Half- Moon LED 3.40E-03 5.36E-05 2.31E-04 Room

  17. Evaluating a prototype device designed to alleviate night vision goggle induced neck strain among military personnel.

    PubMed

    Dibblee, Jenna; Worthy, Portia; Farrell, Philip; Hetzler, Markus; Reid, Susan; Stevenson, Joan; Fischer, Steven

    2015-01-01

    The purpose of this study was verify the design of a novel Helmet System Support Device (HSSD) that can be used by military aircrew to help intervene on and reduce the high prevalence of neck trouble. Twelve healthy participants repeated simulated helicopter aircrew tasks on 3 separate days. On each day they wore a different helmet configuration, where measures of performance, perceived demand/preference and muscular demand were recorded. The results showed that vigilance tasks were performed over 10% faster with the HSSD configuration compared to wearing the normal helmet configuration. Participants were able to maintain static (endurance) postures for 28% longer, and use of the HSSD helped to prevent neck muscle fatigue in the most demanding task. The results of this design verification study indicate that the HSSD may be a realistic, feasible near-term solution to intervene on the high prevalence of neck trouble among rotary-wing aircrew. Practitioner Summary: This paper verifies the effectiveness of the Helmet System Support Device (HSSD) as an on-body personal protective device to help control exposures associated with aircrew neck trouble. The HSSD reduced perceived demand, reduced cumulative muscle activity in select muscles and provided improved fatigue resistance, meeting its desired design objectives.

  18. Global Night-Time Lights for Observing Human Activity

    NASA Technical Reports Server (NTRS)

    Hipskind, Stephen R.; Elvidge, Chris; Gurney, K.; Imhoff, Mark; Bounoua, Lahouari; Sheffner, Edwin; Nemani, Ramakrishna R.; Pettit, Donald R.; Fischer, Marc

    2011-01-01

    We present a concept for a small satellite mission to make systematic, global observations of night-time lights with spatial resolution suitable for discerning the extent, type and density of human settlements. The observations will also allow better understanding of fine scale fossil fuel CO2 emission distribution. The NASA Earth Science Decadal Survey recommends more focus on direct observations of human influence on the Earth system. The most dramatic and compelling observations of human presence on the Earth are the night light observations taken by the Defence Meteorological System Program (DMSP) Operational Linescan System (OLS). Beyond delineating the footprint of human presence, night light data, when assembled and evaluated with complementary data sets, can determine the fine scale spatial distribution of global fossil fuel CO2 emissions. Understanding fossil fuel carbon emissions is critical to understanding the entire carbon cycle, and especially the carbon exchange between terrestrial and oceanic systems.

  19. Active vision in satellite scene analysis

    NASA Technical Reports Server (NTRS)

    Naillon, Martine

    1994-01-01

    In earth observation or planetary exploration it is necessary to have more and, more autonomous systems, able to adapt to unpredictable situations. This imposes the use, in artificial systems, of new concepts in cognition, based on the fact that perception should not be separated from recognition and decision making levels. This means that low level signal processing (perception level) should interact with symbolic and high level processing (decision level). This paper is going to describe the new concept of active vision, implemented in Distributed Artificial Intelligence by Dassault Aviation following a 'structuralist' principle. An application to spatial image interpretation is given, oriented toward flexible robotics.

  20. Pattern recognition and active vision in chickens.

    PubMed

    Dawkins, M S; Woodington, A

    2000-02-10

    Recognition of objects or environmental landmarks is problematic because appearance can vary widely depending on illumination, viewing distance, angle of view and so on. Storing a separate image or 'template' for every possible view requires vast numbers to be stored and scanned, has a high probability of recognition error and appears not to be the solution adopted by primates. However, some invertebrate template matching systems can achieve recognition by 'active vision' in which the animal's own behaviour is used to achieve a fit between template and object, for example by repeatedly following a set path. Recognition is thus limited to views from the set path but achieved with a minimal number of templates. Here we report the first evidence of similar active vision in a bird, in the form of locomotion and individually distinct head movements that give the eyes a similar series of views on different occasions. The hens' ability to recognize objects is also found to decrease when their normal paths are altered.

  1. Leisure Activity Participation of Elderly Individuals with Low Vision.

    ERIC Educational Resources Information Center

    Heinemann, Allen W.

    1988-01-01

    Studied low vision elderly clinic patients (N=63) who reported participation in six categories of leisure activities currently and at onset of vision loss. Found subjects reported significant declines in five of six activity categories. Found prior activity participation was related to current participation only for active crafts, participatory…

  2. Detection of pedestrians for far-infrared automotive night vision systems using learning-based method and head validation

    NASA Astrophysics Data System (ADS)

    Liu, Qiong; Zhuang, Jiajun; Kong, Shufeng

    2013-07-01

    To improve active automotive safety and guarantee the protection of pedestrians at night time, a fast pedestrian detection approach based on a monocular far-infrared camera for driver assistance systems is presented. According to the distribution of gray-level intensity of pedestrian samples, an adaptive local dual threshold segmentation algorithm is executed first to extract candidate regions. Then a novel entropy weighted histograms of oriented gradients (EWHOG) descriptor is proposed for effective pedestrian description in a far-infrared spectrum. For reducing the within-class variance of pedestrians located at different distances, a three-branch classifier combining EWHOG features and a support vector machine (SVM) is introduced for robust pedestrian recognition. To speed up the recognition phase, the resulting support vectors (SVs) are optimized to reduce the number of SVs used for decision-making. A further validation phase is then introduced to suppress the false alarms according to the intensity difference between pedestrians’ heads and their adjacent regions. Comparisons between our approach and conventional approaches are presented, and experimental results show that the presented pedestrian detection framework is very promising.

  3. Part task investigation of multispectral image fusion using gray scale and synthetic color night-vision sensor imagery for helicopter pilotage

    NASA Astrophysics Data System (ADS)

    Steele, Paul M.; Perconti, Philip

    1997-06-01

    Today, night vision sensor and display systems used in the pilotage or navigation of military helicopters are either long wave IR thermal sensors (8 - 12 microns) or image intensified, visible and near IR (0.6 - 0.9 microns), sensors. The sensor imagery is displayed using a monochrome phosphor on a Cathode Ray Tube or night vision goggle. Currently, there is no fielded capability to combine the best attributes of the emissive radiation sensed by the thermal sensor and the reflected radiation sensed by the image intensified sensor into a single fused image. However, recent advances in signal processing have permitted the real time image fusion and display of multispectral sensors in either monochrome or synthetic chromatic form. The merits of such signal processing is explored. A part task simulation using a desktop computer, video playback unit, and a biocular head mounted display was conducted. Response time and accuracy measures of test subject responses to visual perception tasks were taken. Subjective ratings were collected to determine levels of pilot acceptance. In general, fusion based formats resulted in better subject performance. The benefits of integrating synthetic color to fused imagery, however, is dependent on the color algorithm used, the visual task performed, and scene content.

  4. Vision restoration after brain and retina damage: the "residual vision activation theory".

    PubMed

    Sabel, Bernhard A; Henrich-Noack, Petra; Fedorov, Anton; Gall, Carolin

    2011-01-01

    Vision loss after retinal or cerebral visual injury (CVI) was long considered to be irreversible. However, there is considerable potential for vision restoration and recovery even in adulthood. Here, we propose the "residual vision activation theory" of how visual functions can be reactivated and restored. CVI is usually not complete, but some structures are typically spared by the damage. They include (i) areas of partial damage at the visual field border, (ii) "islands" of surviving tissue inside the blind field, (iii) extrastriate pathways unaffected by the damage, and (iv) downstream, higher-level neuronal networks. However, residual structures have a triple handicap to be fully functional: (i) fewer neurons, (ii) lack of sufficient attentional resources because of the dominant intact hemisphere caused by excitation/inhibition dysbalance, and (iii) disturbance in their temporal processing. Because of this resulting activation loss, residual structures are unable to contribute much to everyday vision, and their "non-use" further impairs synaptic strength. However, residual structures can be reactivated by engaging them in repetitive stimulation by different means: (i) visual experience, (ii) visual training, or (iii) noninvasive electrical brain current stimulation. These methods lead to strengthening of synaptic transmission and synchronization of partially damaged structures (within-systems plasticity) and downstream neuronal networks (network plasticity). Just as in normal perceptual learning, synaptic plasticity can improve vision and lead to vision restoration. This can be induced at any time after the lesion, at all ages and in all types of visual field impairments after retinal or brain damage (stroke, neurotrauma, glaucoma, amblyopia, age-related macular degeneration). If and to what extent vision restoration can be achieved is a function of the amount of residual tissue and its activation state. However, sustained improvements require repetitive

  5. A visual test based on a freeware software for quantifying and displaying night-vision disturbances: study in subjects after alcohol consumption

    PubMed Central

    2014-01-01

    Background In this work, we propose the Halo test, a simple visual test based on a freeware software for quantifying and displaying night-vision disturbances perceived by subjects under different experimental conditions, more precisely studying the influence of the alcohol consumption on visual function. Methods In the Halo test, viewed on a monitor, the subject's task consists of detecting luminous peripheral stimuli around a central high-luminance stimulus over a dark background. The test, performed by subjects before and after consuming alcoholic drinks, which deteriorate visual performance, evaluates the influence that alcohol consumption exerts on the visual-discrimination capacity under low illumination conditions. Measurements were made monocularly and binocularly. Pupil size was also measured in both conditions (pre/post). Additionally, we used a double-pass device to measure objectively the optical-quality of the eye and corroborate the results from the Halo test. Results We found a significant deterioration of the discrimination capacity after alcohol consumption, indicating that the higher the breath-alcohol content, the greater the deterioration of the visual-discrimination capacity. After alcohol intake, the graphical results showed a greater area of undetected peripheral stimuli around the central high-luminance stimulus. An enlargement of the pupil was also observed and the optical quality of the eye was deteriorated after alcohol consumption. Conclusions A greater influence of halos and other night-vision disturbances were reported with the Halo test after alcohol consumption. The Halo freeware software constitutes a positive contribution for evaluating nighttime visual performance in clinical applications, such as reported here, but also in patients after refractive surgery (where halos are present) or for monitoring (time course) some ocular pathologies under pharmacological treatment. PMID:25079703

  6. New weather depiction technology for night vision goggle (NVG) training: 3D virtual/augmented reality scene-weather-atmosphere-target simulation

    NASA Astrophysics Data System (ADS)

    Folaron, Michelle; Deacutis, Martin; Hegarty, Jennifer; Vollmerhausen, Richard; Schroeder, John; Colby, Frank P.

    2007-04-01

    US Navy and Marine Corps pilots receive Night Vision Goggle (NVG) training as part of their overall training to maintain the superiority of our forces. This training must incorporate realistic targets; backgrounds; and representative atmospheric and weather effects they may encounter under operational conditions. An approach for pilot NVG training is to use the Night Imaging and Threat Evaluation Laboratory (NITE Lab) concept. The NITE Labs utilize a 10' by 10' static terrain model equipped with both natural and cultural lighting that are used to demonstrate various illumination conditions, and visual phenomena which might be experienced when utilizing night vision goggles. With this technology, the military can safely, systematically, and reliably expose pilots to the large number of potentially dangerous environmental conditions that will be experienced in their NVG training flights. A previous SPIE presentation described our work for NAVAIR to add realistic atmospheric and weather effects to the NVG NITE Lab training facility using the NVG - WDT(Weather Depiction Technology) system (Colby, et al.). NVG -WDT consist of a high end multiprocessor server with weather simulation software, and several fixed and goggle mounted Heads Up Displays (HUDs). Atmospheric and weather effects are simulated using state-of-the-art computer codes such as the WRF (Weather Research μ Forecasting) model; and the US Air Force Research Laboratory MODTRAN radiative transport model. Imagery for a variety of natural and man-made obscurations (e.g. rain, clouds, snow, dust, smoke, chemical releases) are being calculated and injected into the scene observed through the NVG via the fixed and goggle mounted HUDs. This paper expands on the work described in the previous presentation and will describe the 3D Virtual/Augmented Reality Scene - Weather - Atmosphere - Target Simulation part of the NVG - WDT. The 3D virtual reality software is a complete simulation system to generate realistic

  7. Geometric Variational Methods for Controlled Active Vision

    DTIC Science & Technology

    2006-08-01

    Haker , L. Zhu, and A. Tannenbaum, ``Optimal mass transport for registration and warping’’ Int. Journal Computer Vision, volume 60, 2004, pp. 225-240. G...pp. 119-142. A. Angenent, S. Haker , and A. Tannenbaum, ``Minimizing flows for the Monge-Kantorovich problem,’’ SIAM J. Math. Analysis, volume 35...Shape analysis of structures using spherical wavelets’’ (with S. Haker and D. Nain), Proceeedings of MICCAI, 2005. ``Affine surface evolution for 3D

  8. Global vision systems regulatory and standard setting activities

    NASA Astrophysics Data System (ADS)

    Tiana, Carlo; Münsterer, Thomas

    2016-05-01

    A number of committees globally, and the Regulatory Agencies they support, are active delivering and updating performance standards for vision system: Enhanced, Synthetic and Combined, as they apply to both Fixed Wing and, more recently, Rotorcraft operations in low visibility. We provide an overview of each committee's present and past work, as well as an update of recent activities and future goals.

  9. Night Sweats

    MedlinePlus

    Symptoms Night sweats By Mayo Clinic Staff Night sweats are repeated episodes of extreme perspiration that may soak your nightclothes or ... these episodes are usually not labeled as night sweats and typically aren't a sign of a ...

  10. Citizens' visions on active assisted living.

    PubMed

    Gudowsky, Niklas; Sotoudeh, Mahshid

    2015-01-01

    People aged 65 years and older are the fastest growing section of the population in many countries. Great hopes are projected on technology to support solutions for many of the challenges arising from this trend, thus making our lives more independent, more efficient and safer with a higher quality of life. But, as research and innovation ventures are often closely linked to the market, their focus may lead to biased planning in research and development as well as in policy-making with severe social and economic consequences. Thus the main research question concerned desirable settings of ageing in the future from different perspectives. The participatory foresight study CIVISTI-AAL cross-linked knowledge of lay persons, experts and stakeholders to include a wide variety of perspectives and values into productive long-term planning of research and development. Results include citizens' visions for autonomous living in 2050, implicitly and explicitly containing basic needs towards technological, social and organizational development as well as recommendations for implementation. Conclusions suggest that personalized health and living environments play an important part in the lay persons' view of aging in the future, but only if technologies support social and organizational innovations and yet do not neglect the importance of social affiliation and inclusion.

  11. Using perturbations to identify the brain circuits underlying active vision.

    PubMed

    Wurtz, Robert H

    2015-09-19

    The visual and oculomotor systems in the brain have been studied extensively in the primate. Together, they can be regarded as a single brain system that underlies active vision--the normal vision that begins with visual processing in the retina and extends through the brain to the generation of eye movement by the brainstem. The system is probably one of the most thoroughly studied brain systems in the primate, and it offers an ideal opportunity to evaluate the advantages and disadvantages of the series of perturbation techniques that have been used to study it. The perturbations have been critical in moving from correlations between neuronal activity and behaviour closer to a causal relation between neuronal activity and behaviour. The same perturbation techniques have also been used to tease out neuronal circuits that are related to active vision that in turn are driving behaviour. The evolution of perturbation techniques includes ablation of both cortical and subcortical targets, punctate chemical lesions, reversible inactivations, electrical stimulation, and finally the expanding optogenetic techniques. The evolution of perturbation techniques has supported progressively stronger conclusions about what neuronal circuits in the brain underlie active vision and how the circuits themselves might be organized.

  12. Automated, long-range, night/day, active-SWIR face recognition system

    NASA Astrophysics Data System (ADS)

    Lemoff, Brian E.; Martin, Robert B.; Sluch, Mikhail; Kafka, Kristopher M.; Dolby, Andrew; Ice, Robert

    2014-06-01

    Covert, long-range, night/day identification of stationary human subjects using face recognition has been previously demonstrated using the active-SWIR Tactical Imager for Night/Day Extended-Range Surveillance (TINDERS) system. TINDERS uses an invisible, eye-safe, SWIR laser illuminator to produce high-quality facial imagery under conditions ranging from bright sunlight to total darkness. The recent addition of automation software to TINDERS has enabled the autonomous identification of moving subjects at distances greater than 100 m. Unlike typical cooperative, short range face recognition scenarios, where positive identification requires only a single face image, the SWIR wavelength, long distance, and uncontrolled conditions mean that positive identification requires fusing the face matching results from multiple captured images of a single subject. Automation software is required to initially detect a person, lock on and track the person as they move, and select video frames containing high-quality frontal face images for processing. Fusion algorithms are required to combine the matching results from multiple frames to produce a high-confidence match. These automation functions will be described, and results showing automated identification of moving subjects, night and day, at multiple distances will be presented.

  13. Teacher Activism: Enacting a Vision for Social Justice

    ERIC Educational Resources Information Center

    Picower, Bree

    2012-01-01

    This qualitative study focused on educators who participated in grassroots social justice groups to explore the role teacher activism can play in the struggle for educational justice. Findings show teacher activists made three overarching commitments: to reconcile their vision for justice with the realities of injustice around them; to work within…

  14. Effects of vigorous late-night exercise on sleep quality and cardiac autonomic activity.

    PubMed

    Myllymäki, Tero; Kyröläinen, Heikki; Savolainen, Katri; Hokka, Laura; Jakonen, Riikka; Juuti, Tanja; Martinmäki, Kaisu; Kaartinen, Jukka; Kinnunen, Marja-Liisa; Rusko, Heikki

    2011-03-01

    Sleep is the most important period for recovery from daily load. Regular physical activity enhances overall sleep quality, but the effects of acute exercise on sleep are not well defined. In sleep hygiene recommendations, intensive exercising is not suggested within the last 3 h before bed time, but this recommendation has not been adequately tested experimentally. Therefore, the effects of vigorous late-night exercise on sleep were examined by measuring polysomnographic, actigraphic and subjective sleep quality, as well as cardiac autonomic activity. Eleven (seven men, four women) physically fit young adults (VO(2max) 54±8 mL·kg(-1)·min(-1) , age 26±3 years) were monitored in a sleep laboratory twice in a counterbalanced order: (1) after vigorous late-night exercise; and (2) after a control day without exercise. The incremental cycle ergometer exercise until voluntary exhaustion started at 21:00±00:28 hours, lasted for 35±3 min, and ended 2:13±00:19 hours before bed time. The proportion of non-rapid eye movement sleep was greater after the exercise day than the control day (P<0.01), while no differences were seen in actigraphic or subjective sleep quality. During the whole sleep, no differences were found in heart rate (HR) variability, whereas HR was higher after the exercise day than the control day (54±7 versus 51±7, P<0.01), and especially during the first three sleeping hours. The results indicate that vigorous late-night exercise does not disturb sleep quality. However, it may have effects on cardiac autonomic control of heart during the first sleeping hours.

  15. Brain cholinesterase activity of nestling great egrets, snowy egrets and black-crowned night-herons.

    PubMed

    Custer, T W; Ohlendorf, H M

    1989-07-01

    inhibition of brain cholinesterase (ChE) activity in birds is often used to diagnose exposure or death from organophosphorus or carbamate pesticides. Brain ChE activity in the young of altricial species increases with age; however, this relationship has only been demonstrated in the European starling (Sturnus vulgaris). Brain ChE activity of nestling great egrets (Casmerodius albus) collected from a colony in Texas (USA) increased significantly with age and did not differ among individuals from different nests. Brain ChE activity of nestling snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax) collected in one colony each from Rhode Island, Texas and California (USA) also increased significantly with age and did not differ among individuals from different nests or colonies. This study further demonstrates that age must be considered when evaluating exposure of nestling altricial birds to ChE inhibitors.

  16. Brain cholinesterase activity of nestling great egrets snowy egrets and black-crowned night-herons

    USGS Publications Warehouse

    Custer, T.W.; Ohlendorf, H.M.

    1989-01-01

    Inhibition of brain cholinesterase (ChE) activity in birds is often used to diagnose exposure or death from organophosphorus or carbamate pesticides. Brain ChE activity in the young of altricial species increases with age; however, this relationship has only been demonstrated in the European starling (Sturnus vulgaris). Brain ChE activity of nestling great egrets (Casmerodius albus) collected from a colony in Texas (USA) increased significantly with age and did not differ among individuals from different nests. Brain ChE activity of nestling snowy egrets (Egretta thula) and black-crowned night-herons (Nycticorax nycticorax) collected in one colony each from Rhode Island, Texas and California (USA) also increased significantly with age and did not differ among individuals from different nests or colonies. This study further demonstrates that age must be considered when evaluating exposure of nestling altricial birds to ChE inhibitors.

  17. Brain cholinesterase activity of nestling great egrets, snowy egrets, and black-crowned night-herons

    USGS Publications Warehouse

    Custer, T.W.; Ohlendorf, H.M.

    1989-01-01

    Inhibition of brain cholinesterase (ChE) activity in birds is often used to diagnose exposure or death from organophosphorus or carbmate pesticides. Brain ChE activity in the young of altricial species increase with age; however, this relationship has only been demonstrated in the European starling (Sturnus vulgaris). Brain ChE activity of nestling great egrets (Casmerodius albus) collected from a colony in Texas increased significantly with age and did not differ among individuals from different nests. Brain ChE activity of nestling snowy egrets (Egretta thula) and black-crowned night -herons (Nycticorax nycticorax) collected in one colony each from Rhode Island, Texas, and California also increased significantly with age and did not differ among individuals from different nests or colonies. This study further demonstrates that age must be considered when evaluating exposure of nestling altricial birds to ChE inhibitors.

  18. Real and virtual robot head for active vision research

    NASA Astrophysics Data System (ADS)

    Marapane, Suresh B.; Lassiter, Nils T.; Trivedi, Mohan M.

    1992-11-01

    In the emerging paradigm of animate vision, the visual processes are not thought of as being independent of cognitive or motor processing, but as an integrated system within the context of visual behavior. Intimate coupling of sensory and motor systems have found to improve significantly the performance of behavior based vision systems. In order to conduct research in animate vision one requires an active image acquisition platform. This platform should possess the capability to change vision geometrical and optical parameters of the sensors under the control of a computer. This has led to the development of several robotic sensory-motor systems with multiple degrees of freedoms (DOF). In this paper we describe the status of on going work in developing a sensory-motor robotic system, R2H, with ten degrees of freedoms (DOF) for research in active vision. A Graphical Simulation and Animation (GSA) environment is also presented. The objective of building the GSA system is to create an environment to aid the researchers in developing high performance and reliable software and hardware in a most effective manner. The GSA includes a complete kinematic simulation of the R2H system, it''s sensors and it''s workspace. GSA environment is not meant to be a substitute for performing real experiments but is to complement it. Thus, the GSA environment will be an integral part of the total research effort. With the aid of the GSA environment a Depth from Defocus (DFD), Depth from Vergence, and Depth from Stereo modules have been implemented and tested. The power and usefulness of the GSA system as a research tool is demonstrated by acquiring and analyzing stereo images in the virtual world.

  19. Unexpected Levels of Biological Activity during the Polar Night Offer New Perspectives on a Warming Arctic.

    PubMed

    Berge, Jørgen; Daase, Malin; Renaud, Paul E; Ambrose, William G; Darnis, Gerald; Last, Kim S; Leu, Eva; Cohen, Jonathan H; Johnsen, Geir; Moline, Mark A; Cottier, Finlo; Varpe, Øystein; Shunatova, Natalia; Bałazy, Piotr; Morata, Nathalie; Massabuau, Jean-Charles; Falk-Petersen, Stig; Kosobokova, Ksenia; Hoppe, Clara J M; Węsławski, Jan Marcin; Kukliński, Piotr; Legeżyńska, Joanna; Nikishina, Daria; Cusa, Marine; Kędra, Monika; Włodarska-Kowalczuk, Maria; Vogedes, Daniel; Camus, Lionel; Tran, Damien; Michaud, Emma; Gabrielsen, Tove M; Granovitch, Andrei; Gonchar, Anya; Krapp, Rupert; Callesen, Trine A

    2015-10-05

    The current understanding of Arctic ecosystems is deeply rooted in the classical view of a bottom-up controlled system with strong physical forcing and seasonality in primary-production regimes. Consequently, the Arctic polar night is commonly disregarded as a time of year when biological activities are reduced to a minimum due to a reduced food supply. Here, based upon a multidisciplinary ecosystem-scale study from the polar night at 79°N, we present an entirely different view. Instead of an ecosystem that has entered a resting state, we document a system with high activity levels and biological interactions across most trophic levels. In some habitats, biological diversity and presence of juvenile stages were elevated in winter months compared to the more productive and sunlit periods. Ultimately, our results suggest a different perspective regarding ecosystem function that will be of importance for future environmental management and decision making, especially at a time when Arctic regions are experiencing accelerated environmental change [1].

  20. Cholinesterase activity in black-crowned night-herons exposed to fenthion-treated water

    USGS Publications Warehouse

    Smith, G.J.; Spann, J.W.; Hill, E.F.

    1986-01-01

    Fenthion, (O,O-Dimethyl O-(3-methyl-4-(methylthio)phenyl) phosphorothioate), a widely used mosquito control agent, has caused wildlife mortality. To simulate a shallow wetland environment, an exposure chamber was used containing water treated with fenthion at 1 and 10 times the field application rate of 112 g active ingredient (AI)/ha. This system permitted an evaluation of exposure routes and the effects of fenthion in a representative species of wading bird, the black-crowned night-heron (Nycticorax nycticorax). The results suggested that herons received only a dermal exposure, and that their brain acetylcholinesterase activity was not significantly inhibited. In contrast, however, plasma butyrylcholinesterase activity was inhibited, suggesting the herons were exposed to the insecticide. The application rates and types of exposures were not life-threatening in this species.

  1. Vector disparity sensor with vergence control for active vision systems.

    PubMed

    Barranco, Francisco; Diaz, Javier; Gibaldi, Agostino; Sabatini, Silvio P; Ros, Eduardo

    2012-01-01

    This paper presents an architecture for computing vector disparity for active vision systems as used on robotics applications. The control of the vergence angle of a binocular system allows us to efficiently explore dynamic environments, but requires a generalization of the disparity computation with respect to a static camera setup, where the disparity is strictly 1-D after the image rectification. The interaction between vision and motor control allows us to develop an active sensor that achieves high accuracy of the disparity computation around the fixation point, and fast reaction time for the vergence control. In this contribution, we address the development of a real-time architecture for vector disparity computation using an FPGA device. We implement the disparity unit and the control module for vergence, version, and tilt to determine the fixation point. In addition, two on-chip different alternatives for the vector disparity engines are discussed based on the luminance (gradient-based) and phase information of the binocular images. The multiscale versions of these engines are able to estimate the vector disparity up to 32 fps on VGA resolution images with very good accuracy as shown using benchmark sequences with known ground-truth. The performances in terms of frame-rate, resource utilization, and accuracy of the presented approaches are discussed. On the basis of these results, our study indicates that the gradient-based approach leads to the best trade-off choice for the integration with the active vision system.

  2. Robust active stereo vision using Kullback-Leibler divergence.

    PubMed

    Wang, Yongchang; Liu, Kai; Hao, Qi; Wang, Xianwang; Lau, Daniel L; Hassebrook, Laurence G

    2012-03-01

    Active stereo vision is a method of 3D surface scanning involving the projecting and capturing of a series of light patterns where depth is derived from correspondences between the observed and projected patterns. In contrast, passive stereo vision reveals depth through correspondences between textured images from two or more cameras. By employing a projector, active stereo vision systems find correspondences between two or more cameras, without ambiguity, independent of object texture. In this paper, we present a hybrid 3D reconstruction framework that supplements projected pattern correspondence matching with texture information. The proposed scheme consists of using projected pattern data to derive initial correspondences across cameras and then using texture data to eliminate ambiguities. Pattern modulation data are then used to estimate error models from which Kullback-Leibler divergence refinement is applied to reduce misregistration errors. Using only a small number of patterns, the presented approach reduces measurement errors versus traditional structured light and phase matching methodologies while being insensitive to gamma distortion, projector flickering, and secondary reflections. Experimental results demonstrate these advantages in terms of enhanced 3D reconstruction performance in the presence of noise, deterministic distortions, and conditions of texture and depth contrast.

  3. A low-noise 15-μm pixel-pitch 640×512 hybrid InGaAs image sensor for night vision

    NASA Astrophysics Data System (ADS)

    Guellec, Fabrice; Dubois, Sébastien; de Borniol, Eric; Castelein, Pierre; Martin, Sébastien; Guiguet, Romain; Tchagaspanian, Micha"l.; Rouvié, Anne; Bois, Philippe

    2012-03-01

    Hybrid InGaAs focal plane arrays are very interesting for night vision because they can benefit from the nightglow emission in the Short Wave Infrared band. Through a collaboration between III-V Lab and CEA-Léti, a 640x512 InGaAs image sensor with 15μm pixel pitch has been developed. The good crystalline quality of the InGaAs detectors opens the door to low dark current (around 20nA/cm2 at room temperature and -0.1V bias) as required for low light level imaging. In addition, the InP substrate can be removed to extend the detection range towards the visible spectrum. A custom readout IC (ROIC) has been designed in a standard CMOS 0.18μm technology. The pixel circuit is based on a capacitive transimpedance amplifier (CTIA) with two selectable charge-to-voltage conversion gains. Relying on a thorough noise analysis, this input stage has been optimized to deliver low-noise performance in high-gain mode with a reasonable concession on dynamic range. The exposure time can be maximized up to the frame period thanks to a rolling shutter approach. The frame rate can be up to 120fps or 60fps if the Correlated Double Sampling (CDS) capability of the circuit is enabled. The first results show that the CDS is effective at removing the very low frequency noise present on the reference voltage in our test setup. In this way, the measured total dark noise is around 90 electrons in high-gain mode for 8.3ms exposure time. It is mainly dominated by the dark shot noise for a detector temperature settling around 30°C when not cooled. The readout noise measured with shorter exposure time is around 30 electrons for a dynamic range of 71dB in high-gain mode and 108 electrons for 79dB in low-gain mode.

  4. Night-Time Light Data: A Good Proxy Measure for Economic Activity?

    PubMed Central

    Mellander, Charlotta; Lobo, José; Stolarick, Kevin; Matheson, Zara

    2015-01-01

    Much research has suggested that night-time light (NTL) can be used as a proxy for a number of variables, including urbanization, density, and economic growth. As governments around the world either collect census data infrequently or are scaling back the amount of detail collected, alternate sources of population and economic information like NTL are being considered. But, just how close is the statistical relationship between NTL and economic activity at a fine-grained geographical level? This paper uses a combination of correlation analysis and geographically weighted regressions in order to examine if light can function as a proxy for economic activities at a finer level. We use a fine-grained geo-coded residential and industrial full sample micro-data set for Sweden, and match it with both radiance and saturated light emissions. We find that the correlation between NTL and economic activity is strong enough to make it a relatively good proxy for population and establishment density, but the correlation is weaker in relation to wages. In general, we find a stronger relation between light and density values, than with light and total values. We also find a closer connection between radiance light and economic activity, than with saturated light. Further, we find the link between light and economic activity, especially estimated by wages, to be slightly overestimated in large urban areas and underestimated in rural areas. PMID:26496428

  5. Intra-night optical activity of the blazar CTA 102 during its maximum state

    NASA Astrophysics Data System (ADS)

    Popov, Velimir; Bachev, Rumen

    2016-11-01

    CTA 102 is known to experience violent outbursts in the optical, the latest of which happened just recently (ATel #9756, ATel #9732). Following these reports we observed this object for four nights (17.11.2016 - 20.11.2016) in a search for intra-night variability.

  6. Scene interpretation module for an active vision system

    NASA Astrophysics Data System (ADS)

    Remagnino, P.; Matas, J.; Illingworth, John; Kittler, Josef

    1993-08-01

    In this paper an implementation of a high level symbolic scene interpreter for an active vision system is considered. The scene interpretation module uses low level image processing and feature extraction results to achieve object recognition and to build up a 3D environment map. The module is structured to exploit spatio-temporal context provided by existing partial world interpretations and has spatial reasoning to direct gaze control and thereby achieve efficient and robust processing using spatial focus of attention. The system builds and maintains an awareness of an environment which is far larger than a single camera view. Experiments on image sequences have shown that the system can: establish its position and orientation in a partially known environment, track simple moving objects such as cups and boxes, temporally integrate recognition results to establish or forget object presence, and utilize spatial focus of attention to achieve efficient and robust object recognition. The system has been extensively tested using images from a single steerable camera viewing a simple table top scene containing box and cylinder-like objects. Work is currently progressing to further develop its competences and interface it with the Surrey active stereo vision head, GETAFIX.

  7. Active vision in marmosets: a model system for visual neuroscience.

    PubMed

    Mitchell, Jude F; Reynolds, John H; Miller, Cory T

    2014-01-22

    The common marmoset (Callithrix jacchus), a small-bodied New World primate, offers several advantages to complement vision research in larger primates. Studies in the anesthetized marmoset have detailed the anatomy and physiology of their visual system (Rosa et al., 2009) while studies of auditory and vocal processing have established their utility for awake and behaving neurophysiological investigations (Lu et al., 2001a,b; Eliades and Wang, 2008a,b; Osmanski and Wang, 2011; Remington et al., 2012). However, a critical unknown is whether marmosets can perform visual tasks under head restraint. This has been essential for studies in macaques, enabling both accurate eye tracking and head stabilization for neurophysiology. In one set of experiments we compared the free viewing behavior of head-fixed marmosets to that of macaques, and found that their saccadic behavior is comparable across a number of saccade metrics and that saccades target similar regions of interest including faces. In a second set of experiments we applied behavioral conditioning techniques to determine whether the marmoset could control fixation for liquid reward. Two marmosets could fixate a central point and ignore peripheral flashing stimuli, as needed for receptive field mapping. Both marmosets also performed an orientation discrimination task, exhibiting a saturating psychometric function with reliable performance and shorter reaction times for easier discriminations. These data suggest that the marmoset is a viable model for studies of active vision and its underlying neural mechanisms.

  8. Night Games.

    ERIC Educational Resources Information Center

    Steinbach, Paul

    2001-01-01

    Discusses how to control sports facility outdoor lighting during night games. Different lighting techniques are explored for keeping lighting inside the stadium and not disturb the surrounding community. (GR)

  9. LINE-1 activity as molecular basis for genomic instability associated with light exposure at night.

    PubMed

    Belancio, Victoria P

    2015-01-01

    The original hypothesis that exposure to light at night increases risk of breast cancer via suppression of nocturnal melatonin production was proposed over 2 decades ago. In 2007, shift work that involves circadian disruption has been recognized by the World Health Organization as a probable human carcinogen. Our discovery of melatonin-dependent regulation of LINE-1 retrotransposon expression and mobilization is the latest addition to the list of cellular genes and processes that are affected by light exposure at night. This finding establishes an unexpected health relevant connection between this endogenous DNA damaging agent and environmental light exposure. It also offers an appealing hypothesis pertaining to the origin of genomic instability in the genomes of individuals with light at night- or age-associated disruption of melatonin signaling.

  10. Phase inversion of neural activity in the olfactory and visual systems of a night-migratory bird during migration.

    PubMed

    Rastogi, Ashutosh; Kumari, Yatinesh; Rani, Sangeeta; Kumar, Vinod

    2011-07-01

    Olfactory and visual sensory mechanisms seem to play a critical role in migratory orientation and navigation. How these two mechanisms are functionally linked with other migratory processes is unknown. We investigated this, in relation to the profound behavioural shift that occurs during migration in the night-migratory blackheaded bunting (Emberiza melanocephala). Photosensitive unstimulated birds singly housed in activity cages were subjected to long days (LD 16/8). The activity of each bird was continuously monitored. Daily activity pattern defined the nonmigratory phase (no nocturnal activity) and migratory phase (intense nocturnal activity, Zugunruhe). Body mass and testis size were measured at the beginning and end of the experiment. Long days induced the migratory phenotype (body fattening and Zugunruhe) and testis maturation. The c-fos (Fos) immunoreactivity, as marker of the neural activity of the olfactory and visual subsystems, was measured at midday (8 h after lights-on) and midnight (4 h after lights-off) after the first seven long days (nonmigratory phase) and after seven nights of the Zugunruhe (migratory phase). In the nonmigratory phase, Fos-like immunoreactive (Fos-lir) cells in the olfactory and visual subsystems were high in the day and low at night. In the migratory phase, this was reversed; Fos-lir cells were high at night and low in the day. The phase inversion of neural activity in the olfactory and visual systems in parallel with the behavioral shift suggests a functional coupling between the systems governing migratory flight (expressed as Zugunruhe) and migratory orientation and navigation.

  11. Using Light-at-Night (LAN) Satellite Data for Identifying Clusters of Economic Activities in Europe

    NASA Astrophysics Data System (ADS)

    Rybnikova, N. A.; Portnov, B. A.

    2015-04-01

    Enterprises organized in clusters are often efficient in stimulating urban development, productivity and profit outflows. Identifying clusters of economic activities (EAs) thus becomes an important step in devising regional development policies, aimed at facilitating regional economic development. However, a major problem with cluster identification stems from limited reporting of specific EAs by individual countries and administrative entities. Even Eurostat, which maintains most advances regional databases, provides data for less than 50% of all regional subdivisions of the 3rd tier of the Nomenclature of Territorial Units for Statistics (NUTS3). Such poor reporting impedes identification of EA clusters and economic forces behind them. In this study, we test a possibility that missing data on geographic concentrations of EAs can be reconstructed using Light-at-Night (LAN) satellite measurements, and that such reconstructed data can then be used for the identification of EA clusters. As we hypothesize, LAN, captured by satellite sensors, is characterized by different intensity, depending on its source - production facilities, services, etc., - and this information can be used for EA identification. The study was carried out in three stages. First, using nighttime satellite images, we determined what types of EAs can be identified, with a sufficient degree of accuracy, by LAN they emit. Second, we calculated multivariate statistical models, linking EAs concentrations with LAN intensities and several locational and development attributes of NUTS3 regions in Europe. Next, using the obtained statistical models, we restored missing data on EAs across NUTS3 regions in Europe and identified clusters of EAs, using spatial analysis tools.

  12. Aurora Activities Observed by SNPP VIIRS Day-Night Band during St. Patrick's Day, 2015 G4 Level Geomagnetic Storm

    NASA Astrophysics Data System (ADS)

    Liu, T. C.; Shao, X.; Cao, C.; Zhang, B.; Fung, S. F.; Sharma, S.

    2015-12-01

    A G4 level (severe) geomagnetic storm occurred on March 17 (St. Patrick's Day), 2015 and it is among the strongest geomagnetic storms of the current solar cycle (Solar Cycle 24). The storm is identified as due to the Coronal Mass Ejections (CMEs) which erupted on March 15 from Region 2297 of solar surface. During this event, the geomagnetic storm index Dst reached -223 nT and the geomagnetic aurora electrojet (AE) index increased and reached as high as >2200 nT with large amplitude fluctuations. Aurora occurred in both hemispheres. Ground auroral sightings were reported from Michigan to Alaska and as far south as southern Colorado. The Day Night Band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi-NPP represents a major advancement in night time imaging capabilities. The DNB senses radiance that can span 7 orders of magnitude in one panchromatic (0.5-0.9 μm) reflective solar band and provides imagery of clouds and other Earth features over illumination levels ranging from full sunlight to quarter moon. In this paper, DNB observations of aurora activities during the St. Patrick's Day geomagnetic storm are analyzed. Aurora are observed to evolve with salient features by DNB for orbital pass on the night side (~local time 1:30am) in both hemispheres. The radiance data from DNB observation are collected at the night sides of southern and northern hemispheres and geo-located onto geomagnetic local time (MLT) coordinates. Regions of aurora during each orbital pass are identified through image processing by contouring radiance values and excluding regions with stray light near day-night terminator. The evolution of aurora are characterized with time series of the poleward and low latitude boundary of aurora, their latitude-span and area, peak radiance and total light emission of the aurora region in DNB observation. These characteristic parameters are correlated with solar wind and geomagnetic index parameters.

  13. Examination of Attention Level in Nurses Working Night Shifts in terms of the Relationship between Electrodermal Activity and Sex Hormones

    PubMed Central

    DOLU, Nazan; ELALMIŞ, Derya Deniz; KELOĞLAN, Seval

    2013-01-01

    Introduction Electrodermal activity (EDA) is an electrical activity of eccrine sweat gland stimulated by the sympathetic nervous system. Skin conductance level (SCL) is measured with EDA. SCL and sweat gland activity increase in emotional situations, such as high activation, attention or stress. In this study, we investigated whether working in shifts affects attention level of nurses with EDA and explored the relationship between EDA and sex hormones. Method The study was carried out on nurses working night shifts (16.00–08.00 h) (n=22) and nurses working without a shift (08.00–16.00 h) (n=20). Firstly, The Epworth Sleepiness Scale which evaluates a person’s daytime sleepiness was applied to the subjects. For EDA measurement, Ag/AgCl electrodes were put on two fingers of their dominant hand. SCL was measured via MP30 system and GSR connection. The blood samples were analyzed for cortisol and ACTH hormone levels to investigate the changes in sleep and circadian rhythm. Result It was found that there was no statistically significant difference in skin conductance levels between the groups. Moreover, in the comparison of hormone values between the groups, the cortisol levels in night shift nurses were higher than in those working without a shift. Conclusion Night shift had no significant effect on the attention levels in the nurses. This situation is thought to be related to the fact that the nurses responsible for the night service raise their attention level to the highest point. The reason for higher level of cortisol in nurses working shifts may reflect that cortisol has no effect on the breadth of attention but reflects a high level of stress.

  14. Seasonally different response of photosynthetic activity to daytime and night-time warming in the Northern Hemisphere

    DOE PAGES

    Tan, Jianguang; Piao, Shilong; Chen, Anping; ...

    2014-08-27

    Over the last century the Northern Hemisphere has experienced rapid climate warming, but this warming has not been evenly distributed seasonally, as well as diurnally. The implications of such seasonal and diurnal heterogeneous warming on regional and global vegetation photosynthetic activity, however, are still poorly understood. Here, we investigated for different seasons how photosynthetic activity of vegetation correlates with changes in seasonal daytime and night-time temperature across the Northern Hemisphere (>30°N), using Normalized Difference Vegetation Index (NDVI) data from 1982 to 2011 obtained from the Advanced Very High Resolution Radiometer (AVHRR). Our analysis revealed some striking seasonal differences in themore » response of NDVI to changes in day- versus night-time temperatures. For instance, while higher daytime temperature (Tmax) is generally associated with higher NDVI values across the boreal zone, the area exhibiting a statistically significant positive correlation between Tmax and NDVI is much larger in spring (41% of area in boreal zone – total area 12.6 × 106 km2) than in summer and autumn (14% and 9%, respectively). In contrast to the predominantly positive response of boreal ecosystems to changes in Tmax, increases in Tmax tended to negatively influence vegetation growth in temperate dry regions, particularly during summer. Changes in night-time temperature (Tmin) correlated negatively with autumnal NDVI in most of the Northern Hemisphere, but had a positive effect on spring and summer NDVI in most temperate regions (e.g., Central North America and Central Asia). Such divergent covariance between the photosynthetic activity of Northern Hemispheric vegetation and day- and night-time temperature changes among different seasons and climate zones suggests a changing dominance of ecophysiological processes across time and space. Lastly, understanding the seasonally different responses of vegetation photosynthetic activity to diurnal

  15. The night-time temporal window of locomotor activity in the Namib Desert long-distance wandering spider, Leucorchestris arenicola.

    PubMed

    Nørgaard, Thomas; Henschel, Joh R; Wehner, Rüdiger

    2006-04-01

    Even though being active exclusively after sunset, the male Leucorchestris arenicola spiders are able to return to their point of departure by following bee-line routes of up to several hundreds of meters in length. While performing this kind of long-distance path integration they must rely on external cues to adjust for navigational errors. Many external cues which could be used by the spiders change dramatically or disappear altogether in the transition period from day to night. Hence, it is therefore imperative to know exactly when after sunset the spiders navigate in order to find out how they do it. To explore this question, we monitored their locomotor activity with data loggers equipped with infrared beam sensors. Our results show that the male spiders are most active in the period between the end and the beginning of the astronomical twilight period. Moreover, they prefer the moonless, i.e. darkest times at night. Hence, we conclude that the males are truly-and extremely-nocturnal. We further show that they are able to navigate under the very dim light conditions prevailing on moonless nights, and thus do not have to rely on the moon or on moon-related patterns of polarised light as potential compass cues.

  16. Application of remote thermal imaging and night vision technology to improve endangered wildlife resource management with minimal animal distress and hazard to humans

    NASA Astrophysics Data System (ADS)

    Lavers, C.; Franks, K.; Floyd, M.; Plowman, A.

    2005-01-01

    Advanced electromagnetic sensor systems more commonly associated with the hightech military battlefield may be applied to remote surveillance of wildlife. The first comprehensive study of a wide global variety of Near Infra Red (NIR) and thermal wildlife portraits are presented with this technology: for mammals, birds and other animals. The paper illustrates the safety aspects afforded to zoo staff and personnel in the wild during the day and night from potentially lethal and aggressive animals, and those difficult to approach normally. Such remote sensing systems are non-invasive and provide minimal disruption and distress to animals both in captivity and in the wild. We present some of the veterinarian advantages of such all weather day and night systems to identify sickness and injuries at an early diagnostic stage, as well as age related effects and mammalian cancer. Animals have very different textured surfaces, reflective and emissive properties in the NIR and thermal bands than when compared with the visible spectrum. Some surface features may offer biomimetic materials design advantages.

  17. Night terror

    MedlinePlus

    ... not be disoriented after the episode. Exams and Tests In many cases, no further examination or testing is needed. If the night terror is severe or prolonged, the child may need a psychological evaluation. Treatment In many cases, a child who ...

  18. Active vision system integrating fast and slow processes

    NASA Astrophysics Data System (ADS)

    Castrillon-Santana, Modesto; Guerra-Artal, C.; Hernandez-Sosa, J.; Dominguez-Brito, A.; Isern-Gonzalez, J.; Cabrera-Gamez, Jorge; Hernandez-Tejera, F. M.

    1998-10-01

    This paper describes an Active Vision System whose design assumes a distinction between fast or reactive and slow or background processes. Fast processes need to operate in cycles with critical timeouts that may affect system stability. While slow processes, though necessary, do not compromise system stability if its execution is delayed. Based on this simple taxonomy, a control architecture has been proposed and a prototype implemented that is able to track people in real-time with a robotic head while trying to identify the target. In this system, the tracking mobile is considered as the reactive part of the system while person identification is considered a background task. This demonstrator has been developed using a new generation DSP (TMS320C80) as a specialized coprocessor to deal with fast processes, and a commercial robotic head with a dedicated DSP-based motor controller. These subsystems are hosted by a standard Pentium-Pro PC running Windows NT where slow processes are executed. The flexibility achieved in the design phase and the preliminary results obtained so far seem to validate the approach followed to integrate time- critical and slow tasks on a heterogeneous hardware platform.

  19. Robust active binocular vision through intrinsically motivated learning.

    PubMed

    Lonini, Luca; Forestier, Sébastien; Teulière, Céline; Zhao, Yu; Shi, Bertram E; Triesch, Jochen

    2013-01-01

    The efficient coding hypothesis posits that sensory systems of animals strive to encode sensory signals efficiently by taking into account the redundancies in them. This principle has been very successful in explaining response properties of visual sensory neurons as adaptations to the statistics of natural images. Recently, we have begun to extend the efficient coding hypothesis to active perception through a form of intrinsically motivated learning: a sensory model learns an efficient code for the sensory signals while a reinforcement learner generates movements of the sense organs to improve the encoding of the signals. To this end, it receives an intrinsically generated reinforcement signal indicating how well the sensory model encodes the data. This approach has been tested in the context of binocular vison, leading to the autonomous development of disparity tuning and vergence control. Here we systematically investigate the robustness of the new approach in the context of a binocular vision system implemented on a robot. Robustness is an important aspect that reflects the ability of the system to deal with unmodeled disturbances or events, such as insults to the system that displace the stereo cameras. To demonstrate the robustness of our method and its ability to self-calibrate, we introduce various perturbations and test if and how the system recovers from them. We find that (1) the system can fully recover from a perturbation that can be compensated through the system's motor degrees of freedom, (2) performance degrades gracefully if the system cannot use its motor degrees of freedom to compensate for the perturbation, and (3) recovery from a perturbation is improved if both the sensory encoding and the behavior policy can adapt to the perturbation. Overall, this work demonstrates that our intrinsically motivated learning approach for efficient coding in active perception gives rise to a self-calibrating perceptual system of high robustness.

  20. Radiometric Quantification of Aurora Activities during Severe Geomagnetic Storms from SNPP VIIRS Day-Night Band Observations

    NASA Astrophysics Data System (ADS)

    Shao, X.; Cao, C.; Liu, T. C.; Zhang, B.; Fung, S. F.; Sharma, A. S.

    2015-12-01

    Two severe geomagnetic storms of level G4 occurred so far in 2015. These are among the strongest geomagnetic storms of the current solar cycle (Solar Cycle 24). Both reached G4-Severe level (Kp = 8) on March 17, 2015 and on June 22, 2015, respectively. The March 17 geomagnetic storm is identified as due to the Coronal Mass Ejections (CMEs) which erupted on March 15 from Region 2297 of solar surface. Combined effects of three CMEs produced on June 18, 19 and 21 caused G4-Severe geomagnetic storm on June 22, 2015. During these geomagnetic storms, solar wind interacts with the Earth's magnetic field and causes temporary disturbances of the Earth's magnetosphere and aurora may be seen in low latitude region. The Day Night Band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi-NPP represents a major advancement in night time imaging capabilities. The DNB senses radiance spanning 7 orders of magnitude in one (0.5-0.9 μm) reflective solar band and provides imagery over illumination levels ranging from full sunlight to quarter moon. In this paper, DNB observations of aurora activities during the two geomagnetic storm events are analyzed. During these events, auroras are observed to evolve with salient features by DNB during orbital pass on the night side (~local time 1:30am) in both hemispheres. The radiometricly calibrated DNB observations allow us to quantitatively analyze the large-scale spatial distribution and temporal evolution of aurora during the geomagnetic storms. The radiance data from DNB observation are collected at the night sides of both hemispheres during the two events and geo-located onto geomagnetic local time (MLT) coordinates. Regions of aurora during each orbital pass are identified through image processing by contouring radiance values and excluding regions with stray light near day-night terminator. The evolution of aurora are characterized with time series of the poleward and low latitude boundary of aurora, their

  1. Seasonally different response of photosynthetic activity to daytime and night-time warming in the Northern Hemisphere

    SciTech Connect

    Tan, Jianguang; Piao, Shilong; Chen, Anping; Zeng, Zhenzhong; Ciais, Philippe; Janssens, Ivan A.; Mao, Jiafu; Myneni, Ranga B.; Peng, Shushi; Peñuelas, Josep; Shi, Xiaoying; Vicca, Sara

    2014-08-27

    Over the last century the Northern Hemisphere has experienced rapid climate warming, but this warming has not been evenly distributed seasonally, as well as diurnally. The implications of such seasonal and diurnal heterogeneous warming on regional and global vegetation photosynthetic activity, however, are still poorly understood. Here, we investigated for different seasons how photosynthetic activity of vegetation correlates with changes in seasonal daytime and night-time temperature across the Northern Hemisphere (>30°N), using Normalized Difference Vegetation Index (NDVI) data from 1982 to 2011 obtained from the Advanced Very High Resolution Radiometer (AVHRR). Our analysis revealed some striking seasonal differences in the response of NDVI to changes in day- versus night-time temperatures. For instance, while higher daytime temperature (Tmax) is generally associated with higher NDVI values across the boreal zone, the area exhibiting a statistically significant positive correlation between Tmax and NDVI is much larger in spring (41% of area in boreal zone – total area 12.6 × 106 km2) than in summer and autumn (14% and 9%, respectively). In contrast to the predominantly positive response of boreal ecosystems to changes in Tmax, increases in Tmax tended to negatively influence vegetation growth in temperate dry regions, particularly during summer. Changes in night-time temperature (Tmin) correlated negatively with autumnal NDVI in most of the Northern Hemisphere, but had a positive effect on spring and summer NDVI in most temperate regions (e.g., Central North America and Central Asia). Such divergent covariance between the photosynthetic activity of Northern Hemispheric vegetation and day- and night-time temperature changes among different seasons and climate zones suggests a changing dominance of ecophysiological processes across time and space. Lastly, understanding the seasonally

  2. The reported incidence of man-machine interface issues in Army aviators using the Aviator's Night Vision System (ANVIS) in a combat theatre

    NASA Astrophysics Data System (ADS)

    Hiatt, Keith L.; Rash, Clarence E.

    2011-06-01

    Background: Army Aviators rely on the ANVIS for night operations. Human factors literature notes that the ANVIS man-machine interface results in reports of visual and spinal complaints. This is the first study that has looked at these issues in the much harsher combat environment. Last year, the authors reported on the statistically significant (p<0.01) increased complaints of visual discomfort, degraded visual cues, and incidence of static and dynamic visual illusions in the combat environment [Proc. SPIE, Vol. 7688, 76880G (2010)]. In this paper we present the findings regarding increased spinal complaints and other man-machine interface issues found in the combat environment. Methods: A survey was administered to Aircrew deployed in support of Operation Enduring Freedom (OEF). Results: 82 Aircrew (representing an aggregate of >89,000 flight hours of which >22,000 were with ANVIS) participated. Analysis demonstrated high complaints of almost all levels of back and neck pain. Additionally, the use of body armor and other Aviation Life Support Equipment (ALSE) caused significant ergonomic complaints when used with ANVIS. Conclusions: ANVIS use in a combat environment resulted in higher and different types of reports of spinal symptoms and other man-machine interface issues over what was previously reported. Data from this study may be more operationally relevant than that of the peacetime literature as it is derived from actual combat and not from training flights, and it may have important implications about making combat predictions based on performance in training scenarios. Notably, Aircrew remarked that they could not execute the mission without ANVIS and ALSE and accepted the degraded ergonomic environment.

  3. Active vision task and postural control in healthy, young adults: Synergy and probably not duality.

    PubMed

    Bonnet, Cédrick T; Baudry, Stéphane

    2016-07-01

    In upright stance, individuals sway continuously and the sway pattern in dual tasks (e.g., a cognitive task performed in upright stance) differs significantly from that observed during the control quiet stance task. The cognitive approach has generated models (limited attentional resources, U-shaped nonlinear interaction) to explain such patterns based on competitive sharing of attentional resources. The objective of the current manuscript was to review these cognitive models in the specific context of visual tasks involving gaze shifts toward precise targets (here called active vision tasks). The selection excluded the effects of early and late stages of life or disease, external perturbations, active vision tasks requiring head and body motions and the combination of two tasks performed together (e.g., a visual task in addition to a computation in one's head). The selection included studies performed by healthy, young adults with control and active - difficult - vision tasks. Over 174 studies found in Pubmed and Mendeley databases, nine were selected. In these studies, young adults exhibited significantly lower amplitude of body displacement (center of pressure and/or body marker) under active vision tasks than under the control task. Furthermore, the more difficult the active vision tasks were, the better the postural control was. This underscores that postural control during active vision tasks may rely on synergistic relations between the postural and visual systems rather than on competitive or dual relations. In contrast, in the control task, there would not be any synergistic or competitive relations.

  4. Holographic optogenetic stimulation of patterned neuronal activity for vision restoration.

    PubMed

    Reutsky-Gefen, Inna; Golan, Lior; Farah, Nairouz; Schejter, Adi; Tsur, Limor; Brosh, Inbar; Shoham, Shy

    2013-01-01

    When natural photoreception is disrupted, as in outer-retinal degenerative diseases, artificial stimulation of surviving nerve cells offers a potential strategy for bypassing compromised neural circuits. Recently, light-sensitive proteins that photosensitize quiescent neurons have generated unprecedented opportunities for optogenetic neuronal control, inspiring early development of optical retinal prostheses. Selectively exciting large neural populations are essential for eliciting meaningful perceptions in the brain. Here we provide the first demonstration of holographic photo-stimulation strategies for bionic vision restoration. In blind retinas, we demonstrate reliable holographically patterned optogenetic stimulation of retinal ganglion cells with millisecond temporal precision and cellular resolution. Holographic excitation strategies could enable flexible control over distributed neuronal circuits, potentially paving the way towards high-acuity vision restoration devices and additional medical and scientific neuro-photonics applications.

  5. Night Vision Technology and the Night Attack by Light Infantry

    DTIC Science & Technology

    1992-12-30

    devices for observation must compensate for their low mobility and stationary operating requirements by positioning them in advance to provide...heavily into the model. The target the soldier seeks to engage is the fWh facor. Its degree of mobility and exposure directly effect the ability to hit it...environment of combat. The low mobility , longer range TI systems that are utilized by platoons and companies can play a critical role in the targeting cycle

  6. Ionospheric anomaly due to seismic activities-III: correlation between night time VLF amplitude fluctuations and effective magnitudes of earthquakes in Indian sub-continent

    NASA Astrophysics Data System (ADS)

    Ray, S.; Chakrabarti, S. K.; Mondal, S. K.; Sasmal, S.

    2011-10-01

    We present the results of an analysis of yearlong (2007) monitoring of night time data of the VLF signal amplitude from the Indian Navy station VTX at 18.2 kHz, received by the Indian Centre for Space Physics, Kolkata. We analyzed this data to find out the correlation, if any, between night time amplitude fluctuation and seismic events. We found, analyzing individual cases (with magnitudes >5) as well as statistical analysis (of all the events with effective magnitudes greater than 3.5), that night time fluctuation of the signal amplitude has the highest probability to be beyond the 2_ level about three days prior to seismic events. Thus, the night time fluctuation could be considered as a precursor to enhanced seismic activities.

  7. Exploring techniques for vision based human activity recognition: methods, systems, and evaluation.

    PubMed

    Xu, Xin; Tang, Jinshan; Zhang, Xiaolong; Liu, Xiaoming; Zhang, Hong; Qiu, Yimin

    2013-01-25

    With the wide applications of vision based intelligent systems, image and video analysis technologies have attracted the attention of researchers in the computer vision field. In image and video analysis, human activity recognition is an important research direction. By interpreting and understanding human activity, we can recognize and predict the occurrence of crimes and help the police or other agencies react immediately. In the past, a large number of papers have been published on human activity recognition in video and image sequences. In this paper, we provide a comprehensive survey of the recent development of the techniques, including methods, systems, and quantitative evaluation towards the performance of human activity recognition.

  8. MONIM: the new Met Office Night Illumination Model

    NASA Astrophysics Data System (ADS)

    Revell, S. J.; Hignett, P.

    2004-09-01

    This paper describes a new model developed by the Met Office to predict night-time light levels. The Met Office Night Illumination Model (MONIM) predicts light levels both in the visible (photopic) range and in the waveband to which night vision goggles (NVGs) are sensitive. The model will be used operationally for support of night-time flying operations. The model is described in detail and its light-level forecasts are compared with observations.

  9. Categorisation through evidence accumulation in an active vision system

    NASA Astrophysics Data System (ADS)

    Mirolli, Marco; Ferrauto, Tomassino; Nolfi, Stefano

    2010-12-01

    In this paper, we present an artificial vision system that is trained with a genetic algorithm for categorising five different kinds of images (letters) of different sizes. The system, which has a limited field of view, can move its eye so as to explore the images visually. The analysis of the system at the end of the training process indicates that correct categorisation is achieved by (1) exploiting sensory-motor coordination so as to experience stimuli that facilitate discrimination, and (2) integrating perceptual and/or motor information over time through a process of accumulation of partially conflicting evidence. We discuss our results with respect to the possible different strategies for categorisation and to the possible roles that action can play in perception.

  10. Towards remote sensing of Arctic ice roads and associated human activities using SUOMI NPP night light images

    NASA Astrophysics Data System (ADS)

    Bennett, M.; Smith, L. C.; Stephenson, S. R.

    2014-12-01

    Ice roads are often the only cost-effective means of transporting goods and supplies to communities, mines, and other sites in remote parts of the Arctic. Yet, there is no global dataset for Arctic ice roads. However, remotely sensed images from the SUOMI NPP day/night band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) may allow for the construction of such a dataset. The DNB's high sensitivity to low-level light suggests that while it is not feasible to view ice roads at night per se, other prominent features associated with ice roads can serve as proxies. Using a time series of images taken in winter 2012, 2013, and 2014, SUOMI NPP images are compared with Landsat 8 images and an existing map of the Tibbitt to Contwoyto ice road in the Northwest Territories and Nunavut, Canada. First results reveal that while the ice road's exact path cannot be discerned, key points of human activity along the way can be made out. This bodes well for future applications of DNB imagery to detect ice roads in places like the Russian Federation, for which there is a dearth of publicly available maps. Knowing the location of ice roads is important for two reasons. First, these data can signal sites of natural resource extraction in places for which information is not widely disseminated, such as in the Russian Far East. Second, new geospatial datasets for ice roads can be combined with models assessing impacts of climate change on circumpolar land accessibility (Stephenson et al. 2011) in order to understand where the structural integrity of ice roads may be at risk. As warming temperatures threaten to shorten the season for ice roads, communities and mines alike will need to prepare for changes to their transportation infrastructure, made out of the changing landscape itself.

  11. Repeated psychosocial stress at night affects the circadian activity rhythm of male mice.

    PubMed

    Bartlang, Manuela S; Oster, Henrik; Helfrich-Förster, Charlotte

    2015-06-01

    We have recently shown that molecular rhythms in the murine suprachiasmatic nucleus (SCN) are affected by repeated social defeat (SD) during the dark/active phase (social defeat dark [SDD]), while repeated SD during the light/inactive phase (social defeat light [SDL]) had no influence on PERIOD2::LUCIFERASE explant rhythms in the SCN. Here we assessed the effects of the same stress paradigm by in vivo biotelemetry on 2 output rhythms of the circadian clock (i.e., activity and core body temperature) in wild-type (WT) and clock-deficient Period (Per)1/2 double-mutant mice during and following repeated SDL and SDD. In general, stress had more pronounced effects on activity compared to body temperature rhythms. Throughout the SD procedure, activity and body temperature were markedly increased during the 2 h of stressor exposure at zeitgeber time (ZT) 1 to ZT3 (SDL mice) and ZT13 to ZT15 (SDD mice), which was compensated by decreased activity during the remaining dark phase (SDL and SDD mice) and light phase (SDL mice) in both genotypes. Considerable differences in the activity between SDL and SDD mice were seen in the poststress period. SDD mice exhibited a reduced first activity bout at ZT13, delayed activity onset, and, consequently, a more narrow activity bandwidth compared with single-housed control (SHC) and SDL mice. Given that this effect was absent in Per1/2 mutant SDD mice and persisted under constant darkness conditions in SDD WT mice, it suggests an involvement of the endogenous clock. Taken together, the present findings demonstrate that SDD has long-lasting consequences for the functional output of the biological clock that, at least in part, appear to depend on the clock genes Per1 and Per2.

  12. Physics Based Simulation of Night Vision Goggles

    DTIC Science & Technology

    2000-07-01

    concentric circles of varying brightness. The halo is a two dimensional effect caused by an elastic rebound of electrons hitting the structure of the...response. Since halos are a 2-D effect , occurring in the goggle, they do not change size as a function of distance. Illumination Sources. There are a...the image. The effect called “skyglow” is caused by solar light once the sun is below the horizon. Sunset skyglow lasts well after sunset in middle

  13. Fusion of Night Vision and Thermal Images

    DTIC Science & Technology

    2006-12-01

    Oct 1946) For example, the S1 photocathode used in Gen 0 is made from mixed oxides of silver and caesium (Montoro H.P., Oct 2006) and is not as...antimony-potassium-sodium- caesium and provided about three times the photo sensitivity of Gen 0 products. However this level of amplification still had

  14. Pleiades Visions

    NASA Astrophysics Data System (ADS)

    Whitehouse, M.

    2016-01-01

    Pleiades Visions (2012) is my new musical composition for organ that takes inspiration from traditional lore and music associated with the Pleiades (Seven Sisters) star cluster from Australian Aboriginal, Native American, and Native Hawaiian cultures. It is based on my doctoral dissertation research incorporating techniques from the fields of ethnomusicology and cultural astronomy; this research likely represents a new area of inquiry for both fields. This large-scale work employs the organ's vast sonic resources to evoke the majesty of the night sky and the expansive landscapes of the homelands of the above-mentioned peoples. Other important themes in Pleiades Visions are those of place, origins, cosmology, and the creation of the world.

  15. The influence of active vision on the exoskeleton of intelligent agents

    NASA Astrophysics Data System (ADS)

    Smith, Patrice; Terry, Theodore B.

    2016-04-01

    Chameleonization occurs when a self-learning autonomous mobile system's (SLAMR) active vision scans the surface of which it is perched causing the exoskeleton to changes colors exhibiting a chameleon effect. Intelligent agents having the ability to adapt to their environment and exhibit key survivability characteristics of its environments would largely be due in part to the use of active vision. Active vision would allow the intelligent agent to scan its environment and adapt as needed in order to avoid detection. The SLAMR system would have an exoskeleton, which would change, based on the surface it was perched on; this is known as the "chameleon effect." Not in the common sense of the term, but from the techno-bio inspired meaning as addressed in our previous paper. Active vision, utilizing stereoscopic color sensing functionality would enable the intelligent agent to scan an object within its close proximity, determine the color scheme, and match it; allowing the agent to blend with its environment. Through the use of its' optical capabilities, the SLAMR system would be able to further determine its position, taking into account spatial and temporal correlation and spatial frequency content of neighboring structures further ensuring successful background blending. The complex visual tasks of identifying objects, using edge detection, image filtering, and feature extraction are essential for an intelligent agent to gain additional knowledge about its environmental surroundings.

  16. Poor Vision, Functioning, and Depressive Symptoms: A Test of the Activity Restriction Model

    ERIC Educational Resources Information Center

    Bookwala, Jamila; Lawson, Brendan

    2011-01-01

    Purpose: This study tested the applicability of the activity restriction model of depressed affect to the context of poor vision in late life. This model hypothesizes that late-life stressors contribute to poorer mental health not only directly but also indirectly by restricting routine everyday functioning. Method: We used data from a national…

  17. Purposeful gazing in active vision through phase-based disparity and dynamic vergence control

    NASA Astrophysics Data System (ADS)

    Wu, Liwei; Marefat, Michael M.

    1994-10-01

    In this research we propose solutions to the problems involved in gaze stabilization of a binocular active vision system, i.e., vergence error extraction, and vergence servo control. Gazing is realized by decreasing the disparity which represents the vergence error. A Fourier transform based approach that robustly and efficiently estimates vergence disparity is developed for holding gaze on selected visual target. It is shown that this method has certain advantages over existing approaches. Our work also points out that vision sensor based vergence control system is a dual sampling rate system. Feedback information prediction and dynamic vision-based self-tuning control strategy are investigated to implement vergence control. Experiments on the gaze stabilization using the techniques developed in this paper are performed.

  18. The Effect of Gender and Level of Vision on the Physical Activity Level of Children and Adolescents with Visual Impairment

    ERIC Educational Resources Information Center

    Aslan, Ummuhan Bas; Calik, Bilge Basakci; Kitis, Ali

    2012-01-01

    This study was planned in order to determine physical activity levels of visually impaired children and adolescents and to investigate the effect of gender and level of vision on physical activity level in visually impaired children and adolescents. A total of 30 visually impaired children and adolescents (16 low vision and 14 blind) aged between…

  19. A Study of Light and Electron Microscopy of the Neural Basis for Diurnal and Nocturnal Vision.

    DTIC Science & Technology

    RETINA, *PHOTORECEPTORS, LIPIDS, MORPHOLOGY, ELECTRON MICROSCOPY, COLORS, NERVE CELLS, VISION, NIGHT VISION, SPAIN, BIRDS, CELLS(BIOLOGY), DAYLIGHT, CELL STRUCTURE, ELECTROPHYSIOLOGY, NOCTURNAL ANIMALS .

  20. Reduction of computational complexity in the image/video understanding systems with active vision

    NASA Astrophysics Data System (ADS)

    Kuvich, Gary

    2003-10-01

    The vision system evolved not only as a recognition system, but also as a sensory system for reaching, grasping and other motion activities. In advanced creatures, it became a component of prediction function, allowing creation of environmental models and activity planning. Fast information processing and decision making is vital for any living creature, and requires reduction of informational and computational complexities. The brain achieves this goal using symbolic coding, hierarchical compression, and selective processing of visual information. Network-Symbolic representation, where both systematic structural / logical methods and neural / statistical methods are the parts of a single mechanism, is the most feasible for such models. It converts visual information into the relational Network-Symbolic structures, instead of precise computations of a 3-dimensional models. Narrow foveal vision provides separation of figure from ground, object identification, semantic analysis, and precise control of actions. Rough wide peripheral vision identifies and tracks salient motion, guiding foveal system to salient objects. It also provides scene context. Objects with rigid bodies and other stable systems have coherent relational structures. Hierarchical compression and Network-Symbolic transformations derive more abstract structures that allow invariably recognize a particular structure as an exemplar of class. Robotic systems equipped with such smart vision will be able effectively navigate in any environment, understand situation, and act accordingly.

  1. Three-dimensional data-acquiring system fusing active projection and stereo vision

    NASA Astrophysics Data System (ADS)

    Wu, Jianbo; Zhao, Hong; Tan, Yushan

    2001-09-01

    Combining the active digitizing technique with the passive stereo vision, a novel method is proposed to acquire the 3D data from two 2D images. Based on the principle of stereo vision, and assisting the active dense structure light projecting, the system overcomes the problem of data points matching between two stereo images, which is the most important difficulty occurring in stereo vision. An algorithm based on wavelet transform is proposed here to auto-get the threshold for image segment and extract the grid points. The system described here is mainly applied to digitize the 3D objects in time. Comparing with the general digitizers, it performs the translation from 2D images to 3D data completely, and gets over some shortcomings, such as slow image acquiring and data processing speed, depending on mechanical moving, painting on the object before digitizing, and so on. The system is the same with the non-contact and fast measurement and modeling for the 3D object with freedom surface, and can be employed widely in the fields of Reverse Engineering and CAD/CAM. Experiment proves the efficiency of the new use of shape from stereo vision (SFSV) in engineering.

  2. Visions of the Future. Social Science Activities Text. Teacher's Edition.

    ERIC Educational Resources Information Center

    Melnick, Rob; Ronan, Bernard

    Intended to put both national and global issues into perspective and help students make decisions about their futures, this teacher's edition provides instructional objectives, ideas for discussion and inquiries, test blanks for each section, and answer keys for the 22 activities provided in the accompanying student text. Designed to provide high…

  3. Time variability of Io's volcanic activity from near-IR adaptive optics observations on 100 nights in 2013-2015

    NASA Astrophysics Data System (ADS)

    de Kleer, Katherine; de Pater, Imke

    2016-12-01

    Jupiter's moon Io is a dynamic target, exhibiting extreme and time-variable volcanic activity powered by tidal forcing from Jupiter. We have conducted a campaign of high-cadence observations of Io with the goal of characterizing its volcanic activity. Between Aug 2013 and the end of 2015, we imaged Io on 100 nights in the near-infrared with adaptive optics on the Keck and Gemini N telescopes, which resolve emission from individual volcanic hot spots. During our program, we made over 400 detections of 48 distinct hot spots, some of which were detected 30+ times. We use these observations to derive a timeline of global volcanic activity on Io, which exhibits wide variability from month to month. The timelines of thermal activity at individual volcanic centers have geophysical implications, and will permit future characterization by others. We evaluate hot spot detection limits and give a simple parameterization of the minimum detectable intensity as a function of emission angle, which can be applied to other analyses. We detected three outburst eruptions in August 2013, but no other outburst-scale events were observed in the subsequent ∼90 observations. Either the cluster of events in August 2013 was a rare occurrence, or there is a mechanism causing large events to occur closely-spaced in time. We also detected large eruptions (though not of outburst scale) within days of one another at Kurdalagon Patera and Sethlaus/Gabija Paterae in 2015. As was also seen in the Galileo dataset, the hot spots we detected can be separated into two categories based on their thermal emission: those that are persistently active for 1 year or more at moderate intensity, and those that are only briefly active, are time-variable, and often reach large intensities. A small number of hot spots in the latter category appear and subside in a matter of days, reaching particularly high intensities; although these are not bright enough to qualify as outbursts, their thermal signatures follow

  4. Spatial distribution of Io's volcanic activity from near-IR adaptive optics observations on 100 nights in 2013-2015

    NASA Astrophysics Data System (ADS)

    de Kleer, Katherine; de Pater, Imke

    2016-12-01

    The extreme and time-variable volcanic activity on Jupiter's moon Io is the result of periodic tidal forcing. The spatial distribution of Io's surface heat flux provides an important constraint on models for tidal heat dissipation, yielding information on interior properties and on the depth at which the tidal heat is primarily dissipated. We analyze the spatial distribution of 48 hot spots based on more than 400 total hot spot detections in adaptive optics images taken on 100 nights in 2013-2015 (data presented in de Kleer and de Pater [2016] Time variability of Io's volcanic activity from near-IR adaptive optics 13 observations on 100 nights in 2013-2015). We present full surface maps of Io at multiple near-infrared wavelengths for three epochs during this time period, and show that the longitudinal distribution of hot spots has not changed significantly since the Galileo mission. We find that hot spots that are persistently active at moderate intensities tend to occur at different latitudes/longitudes than those that exhibit sudden brightening events characterized by high peak intensities and subsequent decay phases. While persistent hot spots are located primarily between ± 30°N, hot spots exhibiting bright eruption events occur primarily between 40° and 65° in both the northern and southern hemispheres. In addition, while persistent hot spots occur preferentially on the leading hemisphere, all bright eruptions were detected on the trailing hemisphere, despite the comparable longitudinal coverage of our observations to both hemispheres. A subset of the bright hot spots which are not intense enough to qualify as outburst eruptions resemble outbursts in terms of temporal evolution and spatial distribution, and may be outbursts whose peak emission went unobserved, or else scaled-down versions of the same phenomenon. A statistical analysis finds that large eruptions are more spatially clustered and occur at higher latitudes than 95% of simulated datasets that

  5. Disability Awareness Night[TM]: 2006 Honorees, Sponsors, Teams

    ERIC Educational Resources Information Center

    Exceptional Parent, 2006

    2006-01-01

    This article presents the 2006 honorees, sponsors, and teams for the Disability Awareness Night[TM]. Disability Awareness Night[TM] is a unique and powerful community outreach program. Its vision is to continue to raise awareness outside of the community of individuals with disabilities to continue the goal that this program will open doors to…

  6. Vision based assistive technology for people with dementia performing activities of daily living (ADLs): an overview

    NASA Astrophysics Data System (ADS)

    As'ari, M. A.; Sheikh, U. U.

    2012-04-01

    The rapid development of intelligent assistive technology for replacing a human caregiver in assisting people with dementia performing activities of daily living (ADLs) promises in the reduction of care cost especially in training and hiring human caregiver. The main problem however, is the various kinds of sensing agents used in such system and is dependent on the intent (types of ADLs) and environment where the activity is performed. In this paper on overview of the potential of computer vision based sensing agent in assistive system and how it can be generalized and be invariant to various kind of ADLs and environment. We find that there exists a gap from the existing vision based human action recognition method in designing such system due to cognitive and physical impairment of people with dementia.

  7. NCRP Vision for the Future and Program Area Committee Activities.

    PubMed

    Boice, John D

    2017-02-01

    The National Council on Radiation Protection and Measurements (NCRP) believes that the most critical need for the nation in radiation protection is to train, engage, and retain radiation professionals for the future. Not only is the pipeline shrinking, but for some areas there is no longer a pipe! When the call comes to respond, there may be no one to answer the phone! The NCRP "Where are the Radiation Professionals?" initiative, Council Committee (CC) 2, and this year's annual meeting are to focus our efforts to find solutions and not just reiterate the problems. Our next major initiative is CC 1, where the NCRP is making recommendations for the United States on all things dealing with radiation protection. Our last publication was NCRP Report No. 116, Limitation of Exposure to Ionizing Radiation, in 1993-time for an update. NCRP has seven active Program Area Committees on biology and epidemiology, operational concerns, emergency response and preparedness, medicine, environmental issues and waste management, dosimetry, and communications. A major scientific research initiative is the Million Person Study of Low Dose Radiation Health Effects. It includes workers from the Manhattan Project, nuclear weapons test participants (atomic veterans), industrial radiographers, and early medical workers such as radiologists and technologists. This research will answer the one major gap in radiation risk evaluation: what are the health effects when the exposure occurs gradually over time? Other cutting edge initiatives include a re-evaluation of science behind recommendations for lens of the eye dose limits, recommendations for emergency responders on dosimetry after a major radiological incident, guidance to the National Aeronautics and Space Administration with regard to possible central nervous system effects from galactic cosmic rays (the high energy, high mass particles bounding through space), re-evaluating the population exposure to medical radiation (NCRP Report No

  8. A Computational Model of Active Vision for Visual Search in Human-Computer Interaction

    DTIC Science & Technology

    2010-08-01

    the Model Mixed Density Task CVC Task 3. ANSWERING THE FOUR QUESTIONS OF ACTIVE VISION 3.1. When do the Eyes Move? Modeling Fixation...from two experiments: a mixed density search task and a CVC (consonant-vowel- consonant) search task. The mixed density experiment (Halverson & Hornof...2004b) investigated the effects of varying the visual density of elements in a structured layout. The CVC search experiment (Hornof, 2004

  9. Night terrors. Clinical characteristics and personality patterns.

    PubMed

    Kales, J D; Kales, A; Soldatos, C R; Caldwell, A B; Charney, D S; Martin, E D

    1980-12-01

    The development and clinical course of night terrors and the personality patterns of patients with this disorder were evaluated in 40 adults who had a current complaint of night terrors. Compared with a group of adult sleepwalkers, the patients with night terrors had a later age of onset for their disorder, a higher frequency of events, and an earlier time of night for the occurrence of episodes. Both groups had high levels of psychopathology, with higher values for the night terror group. This sleepwalkers showed active, outwardly directed behavioral patterns, whereas the night terror patients showed an inhibition of outward expressions of aggression and a predominance of anxiety, depression, tendencies obsessive-compulsive/, and phobicness. Although night terrors and sleepwalking in childhood seem to be related primarily to genetic and developmental factors, their persistence and especially their onset in adulthood are found to be related more to psychological factors.

  10. The transition from day-to-night activity is a risk factor for the development of CNS oxygen toxicity in the diurnal fat sand rat (Psammomys obesus).

    PubMed

    Eynan, Mirit; Biram, Adi; Mullokandov, Michael; Kronfeld-Schor, Noga; Paz-Cohen, Rotem; Menajem, Dvir; Arieli, Yehuda

    2017-02-03

    Performance and safety are impaired in employees engaged in shift work. Combat divers who use closed-circuit oxygen diving apparatus undergo part of their training during the night hours. The greatest risk involved in diving with such apparatus is the development of central nervous system oxygen toxicity (CNS-OT). We investigated whether the switch from day-to-night activity may be a risk factor for the development of CNS-OT using a diurnal animal model, the fat sand rat (Psammomys obesus). Animals were kept on a 12:12 light-dark schedule (6 a.m. to 6 p.m. at 500 lx). The study included two groups: (1) Control group: animals were kept awake and active during the day, between 09:00 and 15:00. (2) Experimental group: animals were kept awake and active during the night, between 21:00 and 03:00, when they were exposed to dim light in order to simulate the conditions prevalent during combat diver training. This continued for a period of 3 weeks, 5 days a week. On completion of this phase, 6-sulphatoxymelatonin (6-SMT) levels in urine were determined over a period of 24 h. Animals were then exposed to hyperbaric oxygen (HBO). To investigate the effect of acute melatonin administration, melatonin (50 mg/kg) or its vehicle was administered to the animals in both groups 20 min prior to HBO exposure. After the exposure, the activity of superoxide dismutase, catalase and glutathione peroxidase was measured, as were the levels of neuronal nitric oxide synthase (nNOS) and overall nitrotyrosylation in the cortex and hippocampus. Latency to CNS-OT was significantly reduced after the transition from day-to-night activity. This was associated with alterations in the level of melatonin metabolites secreted in the urine. Acute melatonin administration had no effect on latency to CNS-OT in either of the groups. Nevertheless, the activity of superoxide dismutase and catalase, as well as nitrotyrosine and nNOS levels, were altered in the hippocampus following melatonin

  11. Low Vision Bicycling.

    ERIC Educational Resources Information Center

    Connor, M.

    1992-01-01

    This article considers bicycling as a means of transportation, not recreation, for individuals with low vision. Considered are evaluation of capabilities, watching for child cyclists, central and peripheral field loss, necessary equipment, potential problems, seasonal and weather considerations, night riding, route planning, basic visual skills…

  12. Design and control of active vision based mechanisms for intelligent robots

    NASA Technical Reports Server (NTRS)

    Wu, Liwei; Marefat, Michael M.

    1994-01-01

    In this paper, we propose a design of an active vision system for intelligent robot application purposes. The system has the degrees of freedom of pan, tilt, vergence, camera height adjustment, and baseline adjustment with a hierarchical control system structure. Based on this vision system, we discuss two problems involved in the binocular gaze stabilization process: fixation point selection and vergence disparity extraction. A hierarchical approach to determining point of fixation from potential gaze targets using evaluation function representing human visual behavior to outside stimuli is suggested. We also characterize different visual tasks in two cameras for vergence control purposes, and a phase-based method based on binarized images to extract vergence disparity for vergence control is presented. A control algorithm for vergence control is discussed.

  13. Night nursing – staff's working experiences

    PubMed Central

    Nilsson, Kerstin; Campbell, Ann-Mari; Andersson, Ewa Pilhammar

    2008-01-01

    Background Although the duties and working conditions of registered, and enrolled nurses have previously been described from different perspectives, they have not been examined from the night nursing aspect. The aim of the study was to describe the night nursing staff's working experiences. Methods The design of the study is qualitative and descriptive. Interviews were conducted with 10 registered and 10 enrolled nurses working as night staff at a Swedish University Hospital. The interview guide was thematic and concerned the content of their tasks, as well as the working conditions that constitute night nursing. In addition, the interviews were transcribed verbatim and analyzed using content analysis. Results The night duties have to be performed under difficult conditions that include working silently in dimmed lighting, and making decisions when fatigue threatens. According to the night staff, its main goals are to provide the patients with rest and simultaneously ensure qualified care. Furthermore, the night nursing staff must prepare the ward for the daytime activities. Conclusion The most important point is the team work, which developed between the registered and enrolled nurses and how necessary this team work is when working at night. In order for nurses working at night to be fully appreciated, the communication between day and night staff in health care organizations needs to be developed. Furthermore, it is important to give the night staff opportunities to use its whole field of competence. PMID:18976475

  14. Low Vision

    MedlinePlus

    ... USAJobs Home > Statistics and Data > Low Vision Low Vision Low Vision Defined: Low Vision is defined as the best- ... 2010 U.S. Age-Specific Prevalence Rates for Low Vision by Age, and Race/Ethnicity Table for 2010 ...

  15. Frequency of College Students' Night-Sky Watching Behaviors

    ERIC Educational Resources Information Center

    Kelly, William E.; Kelly, Kathryn E.; Batey, Jason

    2006-01-01

    College students (N = 112) completed the Noctcaelador Inventory, a measure of psychological attachment to the night-sky, and estimated various night-sky watching related activities: frequency and duration of night-sky watching, astro-tourism, ownership of night-sky viewing equipment, and attendance of observatories or planetariums. The results…

  16. A tactile vision substitution system for the study of active sensing.

    PubMed

    Hsu, Brian; Hsieh, Cheng-Han; Yu, Sung-Nien; Ahissar, Ehud; Arieli, Amos; Zilbershtain-Kra, Yael

    2013-01-01

    This paper presents a tactile vision substitution system (TVSS) for the study of active sensing. Two algorithms, namely image processing and trajectory tracking, were developed to enhance the capability of conventional TVSS. Image processing techniques were applied to reduce the artifacts and extract important features from the active camera and effectively converted the information into tactile stimuli with much lower resolution. A fixed camera was used to record the movement of the active camera. A trajectory tracking algorithm was developed to analyze the active sensing strategy of the TVSS users to explore the environment. The image processing subsystem showed advantageous improvement in extracting object's features for superior recognition. The trajectory tracking subsystem, on the other hand, enabled accurately locating the portion of the scene pointed by the active camera and providing profound information for the study of active sensing strategy applied by TVSS users.

  17. Retinal Structures and Visual Cortex Activity are Impaired Prior to Clinical Vision Loss in Glaucoma

    PubMed Central

    Murphy, Matthew C.; Conner, Ian P.; Teng, Cindy Y.; Lawrence, Jesse D.; Safiullah, Zaid; Wang, Bo; Bilonick, Richard A.; Kim, Seong-Gi; Wollstein, Gadi; Schuman, Joel S.; Chan, Kevin C.

    2016-01-01

    Glaucoma is the second leading cause of blindness worldwide and its pathogenesis remains unclear. In this study, we measured the structure, metabolism and function of the visual system by optical coherence tomography and multi-modal magnetic resonance imaging in healthy subjects and glaucoma patients with different degrees of vision loss. We found that inner retinal layer thinning, optic nerve cupping and reduced visual cortex activity occurred before patients showed visual field impairment. The primary visual cortex also exhibited more severe functional deficits than higher-order visual brain areas in glaucoma. Within the visual cortex, choline metabolism was perturbed along with increasing disease severity in the eye, optic radiation and visual field. In summary, this study showed evidence that glaucoma deterioration is already present in the eye and the brain before substantial vision loss can be detected clinically using current testing methods. In addition, cortical cholinergic abnormalities are involved during trans-neuronal degeneration and can be detected non-invasively in glaucoma. The current results can be of impact for identifying early glaucoma mechanisms, detecting and monitoring pathophysiological events and eye-brain-behavior relationships, and guiding vision preservation strategies in the visual system, which may help reduce the burden of this irreversible but preventable neurodegenerative disease. PMID:27510406

  18. Forward-looking activities: incorporating citizens' visions: A critical analysis of the CIVISTI method.

    PubMed

    Gudowsky, Niklas; Peissl, Walter; Sotoudeh, Mahshid; Bechtold, Ulrike

    2012-11-01

    Looking back on the many prophets who tried to predict the future as if it were predetermined, at first sight any forward-looking activity is reminiscent of making predictions with a crystal ball. In contrast to fortune tellers, today's exercises do not predict, but try to show different paths that an open future could take. A key motivation to undertake forward-looking activities is broadening the information basis for decision-makers to help them actively shape the future in a desired way. Experts, laypeople, or stakeholders may have different sets of values and priorities with regard to pending decisions on any issue related to the future. Therefore, considering and incorporating their views can, in the best case scenario, lead to more robust decisions and strategies. However, transferring this plurality into a form that decision-makers can consider is a challenge in terms of both design and facilitation of participatory processes. In this paper, we will introduce and critically assess a new qualitative method for forward-looking activities, namely CIVISTI (Citizen Visions on Science, Technology and Innovation; www.civisti.org), which was developed during an EU project of the same name. Focussing strongly on participation, with clear roles for citizens and experts, the method combines expert, stakeholder and lay knowledge to elaborate recommendations for decision-making in issues related to today's and tomorrow's science, technology and innovation. Consisting of three steps, the process starts with citizens' visions of a future 30-40 years from now. Experts then translate these visions into practical recommendations which the same citizens then validate and prioritise to produce a final product. The following paper will highlight the added value as well as limits of the CIVISTI method and will illustrate potential for the improvement of future processes.

  19. Prospective Evaluation of Mesopic Night Vision and Night Vision Goggle Visual Acuity After Photorefractive Keratectomy (PRK)

    DTIC Science & Technology

    2005-03-01

    DTIC) should direct requests for copies to: Defense Technical Information Center, 8725 John J. Kingman Rd., STE 0944, Ft. Belvior, VA 22060-6218. Non...770-6. 9. Verdon W, Bullimore M, Maloney RK. Visual Performance after Photorefractive Keratectomy. A Prospective Study. Arch Ophthalmol. December

  20. Pollination of Campomanesia phaea (Myrtaceae) by night-active bees: a new nocturnal pollination system mediated by floral scent.

    PubMed

    Cordeiro, G D; Pinheiro, M; Dötterl, S; Alves-Dos-Santos, I

    2017-03-01

    Bees are the most important diurnal pollinators of angiosperms. In several groups of bees a nocturnal/crepuscular habit developed, yet little is known about their role in pollination and whether some plants are adapted specifically to these bees. We used a multidisciplinary approach to investigate the reproductive biology and to understand the role of nocturnal/crepuscular bees in pollination of Campomanesia phaea (Myrtaceae), popularly named cambuci. We studied the floral biology and breeding system of C. phaea. We collected the floral visitors and tested the pollinators' effectiveness. We also determined the floral scents released at night and during daytime, and studied behavioural responses of crepuscular/nocturnal bees towards these scents. The flowers of cambuci were self-incompatible and had pollen as the only resource for flower visitors. Anthesis lasted around 14 h, beginning at 04:30 h at night. The flowers released 14 volatile compounds, mainly aliphatic and aromatic compounds. We collected 52 species of floral visitors, mainly bees. Nocturnal and crepuscular bees (four species) were among the most frequent species and the only effective pollinators. In field bioassays performed at night, nocturnal/crepuscular bees were attracted by a synthetic scent blend consisting of the six most abundant compounds. This study describes the first scent-mediated pollination system between a plant and its nocturnal bee pollinators. Further, C. phaea has several floral traits that do not allow classification into other nocturnal pollination syndromes (e.g. pollinator attraction already before sunrise, with pollen as the only reward), instead it is a plant specifically adapted to nocturnal bees.

  1. Defining filled and empty space: reassessing the filled space illusion for active touch and vision.

    PubMed

    Collier, Elizabeth S; Lawson, Rebecca

    2016-09-01

    In the filled space illusion, an extent filled with gratings is estimated as longer than an equivalent extent that is apparently empty. However, researchers do not seem to have carefully considered the terms filled and empty when describing this illusion. Specifically, for active touch, smooth, solid surfaces have typically been used to represent empty space. Thus, it is not known whether comparing gratings to truly empty space (air) during active exploration by touch elicits the same illusionary effect. In Experiments 1 and 2, gratings were estimated as longer if they were compared to smooth, solid surfaces rather than being compared to truly empty space. Consistent with this, Experiment 3 showed that empty space was perceived as longer than solid surfaces when the two were compared directly. Together these results are consistent with the hypothesis that, for touch, the standard filled space illusion only occurs if gratings are compared to smooth, solid surfaces and that it may reverse if gratings are compared to empty space. Finally, Experiment 4 showed that gratings were estimated as longer than both solid and empty extents in vision, so the direction of the filled space illusion in vision was not affected by the nature of the comparator. These results are discussed in relation to the dual nature of active touch.

  2. An Active Vision Approach to Understanding and Improving Visual Training in the Geosciences

    NASA Astrophysics Data System (ADS)

    Voronov, J.; Tarduno, J. A.; Jacobs, R. A.; Pelz, J. B.; Rosen, M. R.

    2009-12-01

    Experience in the field is a fundamental aspect of geologic training, and its effectiveness is largely unchallenged because of anecdotal evidence of its success among expert geologists. However, there have been only a few quantitative studies based on large data collection efforts to investigate how Earth Scientists learn in the field. In a recent collaboration between Earth scientists, Cognitive scientists and experts in Imaging science at the University of Rochester and Rochester Institute of Technology, we are investigating such a study. Within Cognitive Science, one school of thought, referred to as the Active Vision approach, emphasizes that visual perception is an active process requiring us to move our eyes to acquire new information about our environment. The Active Vision approach indicates the perceptual skills which experts possess and which novices will need to acquire to achieve expert performance. We describe data collection efforts using portable eye-trackers to assess how novice and expert geologists acquire visual knowledge in the field. We also discuss our efforts to collect images for use in a semi-immersive classroom environment, useful for further testing of novices and experts using eye-tracking technologies.

  3. Effectiveness of the anaesthetic MS-222 in gilthead seabream, Sparus aurata: effect of feeding time and day-night variations in plasma MS-222 concentration and GST activity.

    PubMed

    Vera, L M; Montoya, A; Sánchez-Vázquez, F J

    2013-02-17

    Feeding time is a potent zeitgeber capable of synchronising behavioural and physiological daily rhythms in fish. However, the effect of feeding time on the daily rhythm of drugs toxicity and/or effectiveness remains unexplored to date. In this paper we investigated the day/night variations in the effectiveness of an anaesthetic commonly used in fish (Tricaine, MS-222) in a teleost of great chronobiological and aquaculture interest (gilthead seabream). To this end, fish were kept under LD 12:12 and fed at mid-light (ML), mid-darkness (MD) or random times (RD). The time needed to induce anaesthesia (reduction of locomotor activity) during MS-222 exposure (65 mg/L) as well as the recovery period were investigated at ML and MD in the three experimental groups using specialised video tracking software. In addition, daily rhythms of GST activity in the liver (as an indicator of detoxification processes) and plasma MS-222 concentration (related to uptake) were determined. The results revealed that MS-222 effectiveness in the ML group was higher during the day than at night (significant reduction of activity after 3 min vs. 5 min) whereas in the MD group, the daily variation of MS-222 effectiveness was inverted (significant reduction of activity after 7 min at ML vs. 2 min at MD), suggesting that feeding time can shift the day-night variations in the effectiveness of MS-222. Hepatic GST also seemed to be affected by feeding time: in fish fed at MD or RD this enzyme activity showed significant differences during the day, and the highest levels were found at different times of the day in each group. Plasma MS-222 concentrations were higher at ML (142.4±12.8 ng/ml) than at MD (96.3±10.9 ng/ml) (t-Student, p<0.05). These results suggest that the daily variation in MS-222 concentration following exposure might be involved, among other factors, in the existence of day-night variations in the effectiveness of this anaesthetic. Furthermore, manipulation of the feeding schedule

  4. Altered Vision-Related Resting-State Activity in Pituitary Adenoma Patients with Visual Damage

    PubMed Central

    Qian, Haiyan; Wang, Xingchao; Wang, Zhongyan; Wang, Zhenmin; Liu, Pinan

    2016-01-01

    Objective To investigate changes of vision-related resting-state activity in pituitary adenoma (PA) patients with visual damage through comparison to healthy controls (HCs). Methods 25 PA patients with visual damage and 25 age- and sex-matched corrected-to-normal-vision HCs underwent a complete neuro-ophthalmologic evaluation, including automated perimetry, fundus examinations, and a magnetic resonance imaging (MRI) protocol, including structural and resting-state fMRI (RS-fMRI) sequences. The regional homogeneity (ReHo) of the vision-related cortex and the functional connectivity (FC) of 6 seeds within the visual cortex (the primary visual cortex (V1), the secondary visual cortex (V2), and the middle temporal visual cortex (MT+)) were evaluated. Two-sample t-tests were conducted to identify the differences between the two groups. Results Compared with the HCs, the PA group exhibited reduced ReHo in the bilateral V1, V2, V3, fusiform, MT+, BA37, thalamus, postcentral gyrus and left precentral gyrus and increased ReHo in the precuneus, prefrontal cortex, posterior cingulate cortex (PCC), anterior cingulate cortex (ACC), insula, supramarginal gyrus (SMG), and putamen. Compared with the HCs, V1, V2, and MT+ in the PAs exhibited decreased FC with the V1, V2, MT+, fusiform, BA37, and increased FC primarily in the bilateral temporal lobe (especially BA20,21,22), prefrontal cortex, PCC, insular, angular gyrus, ACC, pre-SMA, SMG, hippocampal formation, caudate and putamen. It is worth mentioning that compared with HCs, V1 in PAs exhibited decreased or similar FC with the thalamus, whereas V2 and MT+ exhibited increased FCs with the thalamus, especially pulvinar. Conclusions In our study, we identified significant neural reorganization in the vision-related cortex of PA patients with visual damage compared with HCs. Most subareas within the visual cortex exhibited remarkable neural dysfunction. Some subareas, including the MT+ and V2, exhibited enhanced FC with the thalamic

  5. Recognition of Activities of Daily Living with Egocentric Vision: A Review

    PubMed Central

    Nguyen, Thi-Hoa-Cuc; Nebel, Jean-Christophe; Florez-Revuelta, Francisco

    2016-01-01

    Video-based recognition of activities of daily living (ADLs) is being used in ambient assisted living systems in order to support the independent living of older people. However, current systems based on cameras located in the environment present a number of problems, such as occlusions and a limited field of view. Recently, wearable cameras have begun to be exploited. This paper presents a review of the state of the art of egocentric vision systems for the recognition of ADLs following a hierarchical structure: motion, action and activity levels, where each level provides higher semantic information and involves a longer time frame. The current egocentric vision literature suggests that ADLs recognition is mainly driven by the objects present in the scene, especially those associated with specific tasks. However, although object-based approaches have proven popular, object recognition remains a challenge due to the intra-class variations found in unconstrained scenarios. As a consequence, the performance of current systems is far from satisfactory. PMID:26751452

  6. Evolution of activity patterns and chromatic vision in primates: morphometrics, genetics and cladistics.

    PubMed

    Heesy, C P; Ross, C F

    2001-02-01

    Hypotheses for the adaptive origin of primates have reconstructed nocturnality as the primitive activity pattern for the entire order based on functional/adaptive interpretations of the relative size and orientation of the orbits, body size and dietary reconstruction. Based on comparative data from extant taxa this reconstruction implies that basal primates were also solitary, faunivorous, and arboreal. Recently, primates have been hypothesized to be primitively diurnal, based in part on the distribution of color-sensitive photoreceptor opsin genes and active trichromatic color vision in several extant strepsirrhines, as well as anthropoid primates (Tan & Li, 1999 Nature402, 36; Li, 2000 Am. J. phys. Anthrop. Supple.30, 318). If diurnality is primitive for all primates then the functional and adaptive significance of aspects of strepsirrhine retinal morphology and other adaptations of the primate visual system such as high acuity stereopsis, have been misinterpreted for decades. This hypothesis also implies that nocturnality evolved numerous times in primates. However, the hypothesis that primates are primitively diurnal has not been analyzed in a phylogenetic context, nor have the activity patterns of several fossil primates been considered. This study investigated the evolution of activity patterns and trichromacy in primates using a new method for reconstructing activity patterns in fragmentary fossils and by reconstructing visual system character evolution at key ancestral nodes of primate higher taxa. Results support previous studies that reconstruct omomyiform primates as nocturnal. The larger body sizes of adapiform primates confound inferences regarding activity pattern evolution in this group. The hypothesis of diurnality and trichromacy as primitive for primates is not supported by the phylogenetic data. On the contrary, nocturnality and dichromatic vision are not only primitive for all primates, but also for extant strepsirrhines. Diurnality, and

  7. Effects of changing shift schedules from a full-day to a half-day shift before a night shift on physical activities and sleep patterns of single nurses and married nurses with children.

    PubMed

    Watanabe, Misuzu; Akamatsu, Yasuhiro; Furui, Hikari; Tomita, Teruyuki; Watanabe, Takemasa; Kobayashi, Fumio

    2004-01-01

    To clarify the effects of changing shift schedules from a full-day to a half-day before a night shift, 12 single nurses and 18 married nurses with children that engaged in night shift work in a Japanese hospital were investigated. Subjects worked 2 different shift patterns consisting of a night shift after a half-day shift (HF-N) and a night shift after a day shift (D-N). Physical activity levels were recorded with a physical activity volume meter to measure sleep/wake time more precisely without restricting subjects' activities. The duration of sleep before a night shift of married nurses was significantly shorter than that of single nurses for both shift schedules. Changing shift from the D-N to the HF-N increased the duration of sleep before a night shift for both groups, and made wake-up time earlier for single nurses only. Repeated ANCOVA of the series of physical activities showed significant differences with shift (p < 0.01) and marriage (p < 0.01) for variances, and age (p < 0.05) for a covariance. The paired t-test to compare the effects of changing shift patterns in each subject group and ANCOVA for examining the hourly activity differences between single and married nurses showed that the effects of a change in shift schedules seemed to have less effect on married nurses than single nurses. These differences might due to the differences of their family/home responsibilities.

  8. Night ventilation control strategies in office buildings

    SciTech Connect

    Wang, Zhaojun; Yi, Lingli; Gao, Fusheng

    2009-10-15

    In moderate climates night ventilation is an effective and energy-efficient approach to improve the indoor thermal environment for office buildings during the summer months, especially for heavyweight construction. However, is night ventilation a suitable strategy for office buildings with lightweight construction located in cold climates? In order to answer this question, the whole energy-consumption analysis software EnergyPlus was used to simulate the indoor thermal environment and energy consumption in typical office buildings with night mechanical ventilation in three cities in northern China. The summer outdoor climate data was analyzed, and three typical design days were chosen. The most important factors influencing night ventilation performance such as ventilation rates, ventilation duration, building mass and climatic conditions were evaluated. When night ventilation operation time is closer to active cooling time, the efficiency of night ventilation is higher. With night ventilation rate of 10 ach, the mean radiant temperature of the indoor surface decreased by up to 3.9 C. The longer the duration of operation, the more efficient the night ventilation strategy becomes. The control strategies for three locations are given in the paper. Based on the optimized strategies, the operation consumption and fees are calculated. The results show that more energy is saved in office buildings cooled by a night ventilation system in northern China than ones that do not employ this strategy. (author)

  9. Behavioral, morphological and physiological correlates of diurnal and nocturnal vision in selected wading bird species.

    PubMed

    Rojas, L M; McNeil, R; Cabana, T; Lachapelle, P

    1999-01-01

    We examined in selected wading bird species if diurnal or nocturnal foraging and the use of visual or tactile feeding strategies could be correlated with retinal structure and function. The selected species were the Yellow-crowned Night Heron (Nycticorax violaceus), a crepuscular and nocturnal forager, the Great Blue Heron (Ardea herodias), a mainly crepuscular, but also diurnal and nocturnal feeder, the Roseate Spoonbill (Ajaia ajaja), a mainly crepuscular feeder which forages more at night than during the day, the Cattle (Bubulcus ibis) and Tricolored (Egretta tricolor) egrets and the American White Ibis (Eudocimus ruber) which forage only during daytime. Herons and egrets are visual foragers; ibises and spoonbills are tactile feeders. Electroretinograms were obtained from anesthetized birds in photopic and scotopic conditions to a wide range of light intensities, following which the retinae were processed for histological analysis. Based on rod densities and rods:cones ratios, nocturnal vision capability is greater in the Yellow-crowned Night Heron, followed by the Great Blue Heron and the spoonbill, then by the egrets and the ibis. Visual feeders that forage near dawn or dusk or at night have a higher rods:cones ratio, and consequently a greater night vision capability, than visual feeding species which forage only during daytime. Visual nocturnal feeders have a night vision capability greater than tactile diurnal as well as tactile nocturnal feeders. However, based on maximum scotopic b-wave amplitudes, all species studied have roughly comparable night vision capability. The factor that best discriminates between wading bird species appears to be the daytime visual capabilities. Indeed, the diurnal ibis and egrets have similar cone densities, cones:rods ratios, and photopic a-wave amplitudes, values which are greater than those measured in the two nocturnally active heron species.

  10. Auroral activities observed by SNPP VIIRS day/night band during a long period geomagnetic storm event on April 29-30, 2014

    NASA Astrophysics Data System (ADS)

    Shao, Xi; Cao, Changyong; Liu, Tung-chang; Zhang, Bin; Wang, Wenhui; Fung, Shing F.

    2015-10-01

    The Day/Night Band (DNB) of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi-NPP represents a major advancement in night time imaging capabilities. The DNB senses radiance that can span 7 orders of magnitude in one panchromatic (0.5-0.9 μm) reflective solar band and provides imagery of clouds and other Earth features over illumination levels ranging from full sunlight to quarter moon. When the satellite passes through the day-night terminator, the DNB sensor is affected by stray light due to solar illumination on the instrument. With the implementation of stray light correction, stray light-corrected DNB images enable the observation of aurora occurred in the high latitude regions during geomagnetic storms. In this paper, DNB observations of auroral activities are analyzed during a long period (> 20 hours) of geomagnetic storm event occurred on Apr. 29-30, 2014. The storm event has the Bz component of interplanetary magnetic field (IMF) pointing southward for more than 20 hours. During this event, the geomagnetic storm index Dst reached -67 nT and the geomagnetic auroral electrojet (AE) index increased and reached as high as 1200 nT with large amplitude fluctuations. The event occurred during new moon period and DNB observation has minimum moon light contamination. During this event, auroras are observed by DNB for each orbital pass on the night side (~local time 1:30am) in the southern hemisphere. DNB radiance data are processed to identify regions of aurora during each orbital pass. The evolution of aurora is characterized with time series of the poleward and equatorward boundary of aurora, area, peak radiance and total light emission of the aurora in DNB observation. These characteristic parameters are correlated with solar wind and geomagnetic index parameters. It is found that the evolution of total area-integrated radiance of auroral region over the southern hemisphere correlated well with the ground geomagnetic AE index with correlation

  11. Birth and evolution of visionics

    NASA Astrophysics Data System (ADS)

    Wiseman, Robert S.

    1992-09-01

    The success of the U.S. Army's Night Vision Program at Fort Belvoir, VA was significantly influenced by the evolution and timely culmination of Visionics technology which was initiated by Mr. John Johnson. In the late 1950's, Visionics technology started with concern for Near Infrared (NIR) and Image Intensifier (II) Night Vision developments. It resulted in the Johnson Criteria which coupled system physical characteristics to visual performance by using resolution of line pairs across the minimum dimension of a target. This led to development of image evaluation procedures and standardized laboratory testing. Later the Visionics team addressed the Far Infrared (FIR) system performance and developed a series of FLIR Performance Models. The Visionic's Static Performance Model computer code was accepted and proliferated widely by the mid-70's. Visionics moved from static viewing to address the problems of search effectiveness. Then came more work on target signatures and the consideration of the effects of fog, rain, snow, artillery barrages, and realistic battlefield conditions on system performance in order to assure the utility of fielded equipments for all theaters of interest. The general use of the various Visionics models and methodology throughout Government and Industry is recognition of the contributions made by Mr. John Johnson and his Visionics staff.

  12. Optogenetic activation of melanin-concentrating hormone neurons increases non-rapid eye movement and rapid eye movement sleep during the night in rats.

    PubMed

    Blanco-Centurion, Carlos; Liu, Meng; Konadhode, Roda P; Zhang, Xiaobing; Pelluru, Dheeraj; van den Pol, Anthony N; Shiromani, Priyattam J

    2016-11-01

    Neurons containing melanin-concentrating hormone (MCH) are located in the hypothalamus. In mice, optogenetic activation of the MCH neurons induces both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep at night, the normal wake-active period for nocturnal rodents [R. R. Konadhode et al. (2013) J. Neurosci., 33, 10257-10263]. Here we selectively activate these neurons in rats to test the validity of the sleep network hypothesis in another species. Channelrhodopsin-2 (ChR2) driven by the MCH promoter was selectively expressed by MCH neurons after injection of rAAV-MCHp-ChR2-EYFP into the hypothalamus of Long-Evans rats. An in vitro study confirmed that the optogenetic activation of MCH neurons faithfully triggered action potentials. In the second study, in Long-Evans rats, rAAV-MCH-ChR2, or the control vector, rAAV-MCH-EYFP, were delivered into the hypothalamus. Three weeks later, baseline sleep was recorded for 48 h without optogenetic stimulation (0 Hz). Subsequently, at the start of the lights-off cycle, the MCH neurons were stimulated at 5, 10, or 30 Hz (1 mW at tip; 1 min on - 4 min off) for 24 h. Sleep was recorded during the 24-h stimulation period. Optogenetic activation of MCH neurons increased both REM and NREM sleep at night, whereas during the day cycle, only REM sleep was increased. Delta power, an indicator of sleep intensity, was also increased. In control rats without ChR2, optogenetic stimulation did not increase sleep or delta power. These results lend further support to the view that sleep-active MCH neurons contribute to drive sleep in mammals.

  13. A vision system planner for increasing the autonomy of the Extravehicular Activity Helper/Retriever

    NASA Technical Reports Server (NTRS)

    Magee, Michael

    1993-01-01

    The Extravehicular Activity Retriever (EVAR) is a robotic device currently being developed by the Automation and Robotics Division at the NASA Johnson Space Center to support activities in the neighborhood of the Space Shuttle or Space Station Freedom. As the name implies, the Retriever's primary function will be to provide the capability to retrieve tools and equipment or other objects which have become detached from the spacecraft, but it will also be able to rescue a crew member who may have become inadvertently de-tethered. Later goals will include cooperative operations between a crew member and the Retriever such as fetching a tool that is required for servicing or maintenance operations. This paper documents a preliminary design for a Vision System Planner (VSP) for the EVAR that is capable of achieving visual objectives provided to it by a high level task planner. Typical commands which the task planner might issue to the VSP relate to object recognition, object location determination, and obstacle detection. Upon receiving a command from the task planner, the VSP then plans a sequence of actions to achieve the specified objective using a model-based reasoning approach. This sequence may involve choosing an appropriate sensor, selecting an algorithm to process the data, reorienting the sensor, adjusting the effective resolution of the image using lens zooming capability, and/or requesting the task planner to reposition the EVAR to obtain a different view of the object. An initial version of the Vision System Planner which realizes the above capabilities using simulated images has been implemented and tested. The remaining sections describe the architecture and capabilities of the VSP and its relationship to the high level task planner. In addition, typical plans that are generated to achieve visual goals for various scenarios are discussed. Specific topics to be addressed will include object search strategies, repositioning of the EVAR to improve the

  14. Night Pass over Malaysia

    NASA Video Gallery

    This video showing night lights over Malaysia was taken by the crew of Expedition 28 aboard the International Space Station. This sequence of shots was taken on Aug. 21, 2011, from 19:33:05 to 19:3...

  15. Urinating more at night

    MedlinePlus

    ... you to urinate more often during the night. Caffeine and alcohol after dinner can also lead to ... or urinary tract Drinking a lot of alcohol, caffeine, or other fluids before bedtime Enlarged prostate gland ( ...

  16. One Night in January.

    ERIC Educational Resources Information Center

    Rottmann, Larry

    1992-01-01

    Describes student demonstrations on the night that U.S. planes bombed Iraq in the Persian Gulf War. Compares attitudes and feelings to the Vietnam War era. Concludes that the students incorrectly supported the Gulf War action. (CFR)

  17. Day-night differences in neural activation in histaminergic and serotonergic areas with putative projections to the cerebrospinal fluid in a diurnal brain.

    PubMed

    Castillo-Ruiz, A; Gall, A J; Smale, L; Nunez, A A

    2013-10-10

    In nocturnal rodents, brain areas that promote wakefulness have a circadian pattern of neural activation that mirrors the sleep/wake cycle, with more neural activation during the active phase than during the rest phase. To investigate whether differences in temporal patterns of neural activity in wake-promoting regions contribute to differences in daily patterns of wakefulness between nocturnal and diurnal species, we assessed Fos expression patterns in the tuberomammillary (TMM), supramammillary (SUM), and raphe nuclei of male grass rats maintained in a 12:12 h light-dark cycle. Day-night profiles of Fos expression were observed in the ventral and dorsal TMM, in the SUM, and in specific subpopulations of the raphe, including serotonergic cells, with higher Fos expression during the day than during the night. Next, to explore whether the cerebrospinal fluid is an avenue used by the TMM and raphe in the regulation of target areas, we injected the retrograde tracer cholera toxin subunit beta (CTB) into the ventricular system of male grass rats. While CTB labeling was scarce in the TMM and other hypothalamic areas including the suprachiasmatic nucleus, which contains the main circadian pacemaker, a dense cluster of CTB-positive neurons was evident in the caudal dorsal raphe, and the majority of these neurons appeared to be serotonergic. Since these findings are in agreement with reports for nocturnal rodents, our results suggest that the evolution of diurnality did not involve a change in the overall distribution of neuronal connections between systems that support wakefulness and their target areas, but produced a complete temporal reversal in the functioning of those systems.

  18. Congenital stationary night blindness presenting as Leber's congenital amaurosis.

    PubMed

    Weleber, R G; Tongue, A C

    1987-03-01

    Two siblings with autosomal-recessive congenital stationary night blindness were clinically blind in infancy. Both had markedly abnormal electroretinograms that, in the first child, led consultants at two university centers to make the diagnosis of Leber's congenital amaurosis. The patients had intermittent nystagmus and esotropia, but good photopic vision developed eventually. Scotopic vision was clearly defective in each child. Refractive error in both patients was close to emetropic in early infancy but became myopic by 1 year of age. Congenital stationary night blindness must be considered in the differential diagnosis of the blind infant.

  19. Relation among cytochrome P450, Ah-active PCB congeners and dioxin equivalents in pipping black-crowned night-heron embryos

    SciTech Connect

    Rattner, B.A.; Hatfield, J.S.; Melancon, M.J.; Custer, T.W. . Patuxent Environmental Science Center); Tillitt, D.E. . Midwest Science Center)

    1994-11-01

    Pipping black-crowned night-heron (Nycticorax nycticorax) embryos were collected from a relatively uncontaminated site (next to Chincoteague National Wildlife Refuge, VA) and three polluted sites (Cat Island, Green Bay, Lake Michigan, WI; Bair Island, San Francisco Bay, CA; West Marin Island, San Francisco Bay, CA). Hepatic cytochrome P450-associated mono-oxygenates and cytochrome P450 proteins, induced up to 85-fold relative to the reference site, were associated with concentrations of total polychlorinated biphenyls (PCBs) and 11 PCB congeners that are presumed to express toxicity through the arylhydrocarbon (Ah) receptor. Multiple regression revealed that up to 86% of the variation of cytochrome P450 measurements was accounted for by variation in the concentration of these PCB congeners. Toxic equivalents (TEQs) of sample extracts, predicted mathematically (summed product of PCB congener concentrations and toxic equivalency factors), and dioxin equivalents (TCDD-EQs), derived by bioassay (ethoxyresorufin-O-dealkylase activity of treated H4IIE rat hepatoma cells), were greatest in Cat Island samples. Cytochrome P450-associated monooxygenases and cytochrome P450 proteins were related to TEQs and TCDD-EQs; adjusted r[sup 2] often exceeded 0.5 for the relation among mathematically predicted TEQs and cytochrome P450 measurements. These data extend previous observations in heron embryos of an association between P450 and total PCB burdens to include Ah-active PCB congeners, and presumably other compounds, which interact similarly with the AH receptor. Benzyloxyresorufin O-dealkylase, ethoxyresorufin O-dealkylase, and cytochrome P450 1A appear to be the most reliable measures of exposure to Ah-active PCB congeners in black-crowned night-heron embryos. These findings provide further evidence that cytochrome P450-associated parameters have considerable value as a biomarker for assessing environmental contamination of wetlands.

  20. Relation among cytochrome P450, Ah-active PCB congeners and dioxin equivalents in pipping black- crowned night-heron embryos

    USGS Publications Warehouse

    Rattner, B.A.; Hatfield, J.S.; Melancon, M.J.; Custer, T.W.; Tillitt, D.E.

    1994-01-01

    Pipping black-crowned night-heron (Nycticorax nycticorax) embryos were collected from a relatively uncontaminated site (next to Chincoteague National Wildlife Refuge, VA) and three polluted sites (Cat Island, Green Bay, Lake Michigan, WI; Bair Island, San Francisco Bay, CA; West Marin Island, San Francisco Bay, CA). Hepatic cytochrome P450-associated monooxygenases and cytochrome P450 proteins, induced up to 85- fold relative to the reference site, were associated with concentrations of total polychlorinated biphenyls (PCBs) and 11 PCB congeners that are presumed to express toxicity through the arylhydrocarbon (Ah) receptor. Multiple regression revealed that up to 86% of the variation of cytochrome P450 measurements was accounted for by variation in the concentration of these PCB congeners. Toxic equivalents (TEQs) of sample extracts, predicted mathematically (summed product of PCB congener concentrations and toxic equivalency factors), and dioxin equivalents (TCDD-EQs), derived by bioassay (ethoxyresorufin-O-dealkylase activity of treated H4IIE rat hepatoma cells), were greatest in Cat Island samples. Cytochrome P450-associated monooxygenases and cytochrome P450 proteins were related to TEQs and TCDD-EQs; adjusted r super(2) often exceeded 0.5 for the relation among mathematically predicted TEQs and cytochrome P450 measurements. These data extend previous observations in heron embryos of an association between P450 and total PCB burdens to include Ah- active PCB congeners, and presumably other compounds, which interact similarly with the Ah receptor. Benzyloxyresorufin O-dealkylase, ethoxyresorufin O-dealkylase, and cytochrome P450 1A appear to be the most reliable measures of exposure to Ah-active PCB congeners in black-crowned night-heron embryos. These findings provide further evidence that cytochrome P450-associated parameters have considerable value as a biomarker for assessing environmental contamination of wetlands.

  1. Relation among cytochrome P450, AH-active PCB congeners and dioxin equivalents in pipping black-crowned night-heron embryos

    USGS Publications Warehouse

    Rattner, B.A.; Hatfield, J.S.; Melancon, M.J.; Custer, T.W.; Tillitt, D.E.

    1994-01-01

    Pipping black-crowned night-heron (Nycticorax nycticorax) embryos were collected from a relatively uncontaminated site (next to Chincoteague National Wildlife Refuge, VA) and three polluted sites (Cat Island, Green Bay, Lake Michigan, WI; Bair Island, San Francisco Bay, CA; West Marin Island, San Francisco Bay, CA). Hepatic cytochrome P-450-associated monooxygenases and cytochrome P-450 proteins, induced up to 85-fold relative to the reference site, were associated with concentrations of total polychlorinated biphenyls (PCBs) and 11 PCB congeners that are presumed to express toxicity through the arylhydrocarbon (Ah) receptor. Multiple regression revealed that up to 86% of the variation of cytochrome P450 measurements was accounted for by variation in the concentration of these PCB congeners. Toxic equivalents (TEQs) of sample extracts, predicted mathematically (summed product of PCB congener concentrations and toxic equivalency factors), and dioxin equivalents (TCDD-EQs), derived by bioassay (ethoxyresorufin-O-dealkylase activity of treated H4IIE rat hepatoma cells), were greatest in Cat Island samples. Cytochrome P450-associated monooxygenases and cytochrome P450 proteins were related to TEQs and TCDD-EQs; adjusted r-2 often exceeded 0.5 for the relation among mathematically predicted TEQs and cytochrome P450 measurements. These data extend previous observations in heron embryos of an association between P450 and total PCB burdens to include Ah-active PCB congeners, and presumably other compounds, which interact similarly with the Ah receptor. Benzyloxyresorufin O-dealkylase, ethoxyresorufin O-dealkylase, and cytochrome P450 1A appear to be the most reliable measures of exposure to Ah-active PCB congeners in black-crowned night-heron embryos. These findings provide further evidence that cytochrome P450-associated parameters have considerable value as a biomarker for assessing environmental contamination of wetlands.

  2. Evaluating the performance of close-range 3D active vision systems for industrial design applications

    NASA Astrophysics Data System (ADS)

    Beraldin, J.-Angelo; Gaiani, Marco

    2004-12-01

    In recent years, active three-dimensional (3D) active vision systems or range cameras for short have come out of research laboratories to find niche markets in application fields as diverse as industrial design, automotive manufacturing, geomatics, space exploration and cultural heritage to name a few. Many publications address different issues link to 3D sensing and processing but currently these technologies pose a number of challenges to many recent users, i.e., "what are they, how good are they and how do they compare?". The need to understand, test and integrate those range cameras with other technologies, e.g. photogrammetry, CAD, etc. is driven by the quest for optimal resolution, accuracy, speed and cost. Before investing, users want to be certain that a given range camera satisfy their operational requirements. The understanding of the basic theory and best practices associated with those cameras are in fact fundamental to fulfilling the requirements listed above in an optimal way. This paper addresses the evaluation of active 3D range cameras as part of a study to better understand and select one or a number of them to fulfill the needs of industrial design applications. In particular, object material and surface features effect, calibration and performance evaluation are discussed. Results are given for six different range cameras for close range applications.

  3. Evaluating the performance of close-range 3D active vision systems for industrial design applications

    NASA Astrophysics Data System (ADS)

    Beraldin, J.-Angelo; Gaiani, Marco

    2005-01-01

    In recent years, active three-dimensional (3D) active vision systems or range cameras for short have come out of research laboratories to find niche markets in application fields as diverse as industrial design, automotive manufacturing, geomatics, space exploration and cultural heritage to name a few. Many publications address different issues link to 3D sensing and processing but currently these technologies pose a number of challenges to many recent users, i.e., "what are they, how good are they and how do they compare?". The need to understand, test and integrate those range cameras with other technologies, e.g. photogrammetry, CAD, etc. is driven by the quest for optimal resolution, accuracy, speed and cost. Before investing, users want to be certain that a given range camera satisfy their operational requirements. The understanding of the basic theory and best practices associated with those cameras are in fact fundamental to fulfilling the requirements listed above in an optimal way. This paper addresses the evaluation of active 3D range cameras as part of a study to better understand and select one or a number of them to fulfill the needs of industrial design applications. In particular, object material and surface features effect, calibration and performance evaluation are discussed. Results are given for six different range cameras for close range applications.

  4. Associations between platelet monoamine oxidase-B activity and acquired colour vision loss in a fish-eating population.

    PubMed

    Stamler, Christopher John; Mergler, Donna; Abdelouahab, Nadia; Vanier, Claire; Chan, Hing Man

    2006-01-01

    Platelet monoamine oxidase-B (MAO-B) has been considered a surrogate biochemical marker of neurotoxicity, as it may reflect changes in the monoaminergic system in the brain. Colour vision discrimination, in part a dopamine dependent process, has been used to identify early neurological effects of some environmental and industrial neurotoxicants. The objective of this cross-sectional study was to explore the relationship between platelet MAO-B activity and acquired colour discrimination capacity in fish-consumers from the St. Lawrence River region of Canada. Assessment of acquired dyschromatopsia was determined using the Lanthony D-15 desaturated panel test. Participants classified with dyschromatopsia (n=81) had significantly lower MAO-B activity when compared to those with normal colour vision (n=32) (26.5+/-9.6 versus 31.0+/-9.9 nmol/min/20 microg, P=0.030)). Similarly, Bowman's Colour Confusion Index (CCI) was inversely correlated with MAO-B activity when the vision test was performed with the worst eye only (r=-0.245, P=0.009), the best eye only (r=-0.188, P=0.048) and with both eyes together (r=-0.309, P=0.001). Associations remained significant after adjustment for age and gender when both eyes (P=0.003) and the worst eye (P=0.045) were tested. Adjustment for heavy smoking weakened the association between MAO-B and CCI in the worst eye (P=0.140), but did not alter this association for both eyes (P=0.006). Adjustment for blood-mercury concentrations did not change the association. This study suggests a relationship between reduced MAO-B activity and acquired colour vision loss and both are associated with tobacco smoking. Therefore, results show that platelet MAO-B may be used as a surrogate biochemical marker of acquired colour vision loss.

  5. A re-evaluation of the role of vision in the activity and communication of nocturnal primates.

    PubMed

    Bearder, S K; Nekaris, K A I; Curtis, D J

    2006-01-01

    This paper examines the importance of vision in the lives of nocturnal primates in comparison to diurnal and cathemeral species. Vision is the major sense in all primates and there is evidence that the eyesight of nocturnal species is more acute and variable than has previously been recognized. Case studies of the behaviour of a galago and a loris in open woodland habitats in relation to ambient light show that Galago moholi males are more likely to travel between clumps of vegetation along the ground when the moon is up, and during periods of twilight, whereas they retreat to more continuous vegetation and travel less when the moon sets. This is interpreted as a strategy for avoiding predators that hunt on the ground when it is dark. The travel distances of Loris lydekkerianus are not affected by moonlight but this species reduces its choice of food items from more mobile prey to mainly ants when the moon sets, indicating the importance of light when searching for high-energy supplements to its staple diet. Evidence is presented for the first time to indicate key aspects of nocturnal vision that would benefit from further research. It is suggested that the light and dark facial markings of many species convey information about species and individual identity when animals approach each other at night. Differences in the colour of the reflective eye-shine, and behavioural responses displayed when exposed to white torchlight, point to different kinds of nocturnal vision that are suited to each niche, including the possibility of some degree of colour discrimination. The ability of even specialist nocturnal species to see well in broad daylight demonstrates an inherent flexibility that would enable movement into diurnal niches. The major differences in the sensitivity and perceptual anatomy of diurnal lemurs compared to diurnal anthropoids, and the emergence of cathemerality in lemurs, is interpreted as a reflection of evolution from different ancestral stocks in very

  6. Image/video understanding systems based on network-symbolic models and active vision

    NASA Astrophysics Data System (ADS)

    Kuvich, Gary

    2004-07-01

    Vision is a part of information system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, which is an interpretation of visual information in terms of these knowledge models. It is hard to split the entire system apart, and vision mechanisms cannot be completely understood separately from informational processes related to knowledge and intelligence. Brain reduces informational and computational complexities, using implicit symbolic coding of features, hierarchical compression, and selective processing of visual information. Vision is a component of situation awareness, motion and planning systems. Foveal vision provides semantic analysis, recognizing objects in the scene. Peripheral vision guides fovea to salient objects and provides scene context. Biologically inspired Network-Symbolic representation, in which both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, converts visual information into relational Network-Symbolic structures, avoiding precise artificial computations of 3-D models. Network-Symbolic transformations derive more abstract structures that allows for invariant recognition of an object as exemplar of a class and for a reliable identification even if the object is occluded. Systems with such smart vision will be able to navigate in real environment and understand real-world situations.

  7. Day/night fluctuations in melatonin content, arylalkylamine N-acetyltransferase activity and NAT mRNA expression in the CNS, peripheral tissues and hemolymph of the cockroach, Periplaneta americana.

    PubMed

    Bembenek, Jadwiga; Sehadova, Hana; Ichihara, Naoyuki; Takeda, Makio

    2005-01-01

    Melatonin content measured by a radioenzymatic assay in the brain of the American cockroach (Periplaneta americana) showed a day/night fluctuation with higher levels at night under LD 12:12. The activity of arylalkylamine N-acetyltransferase (NAT) in brain was also higher at night and this pattern continued in constant darkness. The results suggest that the rhythmicity in melatonin content can be caused by NAT. Melatonin content in hemolymph showed an even greater day/night difference, more than 12 times that in brain under LD 12:12. Melatonin levels in retina were also higher at night while NAT activity was not significantly higher at night than at daytime. Using a probe designed from NAT cloned from testes we performed Northern blot analysis of total RNA, which revealed that the level of NAT mRNA was higher in midgut, ovary and female accessory glands than in fat body and brain. The level of transcript in midgut was higher at night, but the levels in ovary and female accessory reproductive gland showed the opposite pattern. We also used the antibody to whole Drosophila melanogaster aaNAT1 protein, seeking a homologous antigen in the cephalic ganglia. NAT-like antigen was detected in several restricted populations of cells in the brain that were partially co-localized with PER-like antigen. The results suggest that NAT exists in multiple forms in various tissues of the cockroach and that its functions and regulations can vary among tissues. The results in the brain led to the conclusion that NAT could be a clock-controlled gene functioning as an output regulator of the circadian clock.

  8. "Twelfth Night" for Kids.

    ERIC Educational Resources Information Center

    Burdett, Lois; Coburn, Christine

    Aimed at primary-age children, this book brings William Shakespeare's "Twelfth Night" to them, recognizing that children, properly guided, will take to Shakespeare's characters and stories like "ducks to water"; in the process they find their inner voices, they collaborate, they improvise, and they communicate. Illustrated with…

  9. Family Science Night

    ERIC Educational Resources Information Center

    Hansen, Holly; Alderman, Helen Christine

    2016-01-01

    The goal of the Family Science Night (FSN) described in this article was to involve culturally and linguistically diverse families in school life so that students would be more vocal, successful, and interactive in science class. The project would also demonstrate to the students that their teacher valued their input in the classroom. The setting…

  10. A night sky model.

    NASA Astrophysics Data System (ADS)

    Erpylev, N. P.; Smirnov, M. A.; Bagrov, A. V.

    A night sky model is proposed. It includes different components of light polution, such as solar twilight, moon scattered light, zodiacal light, Milky Way, air glow and artificial light pollution. The model is designed for calculating the efficiency of astronomical installations.

  11. Lambda Vision

    NASA Astrophysics Data System (ADS)

    Czajkowski, Michael

    2014-06-01

    There is an explosion in the quantity and quality of IMINT data being captured in Intelligence Surveillance and Reconnaissance (ISR) today. While automated exploitation techniques involving computer vision are arriving, only a few architectures can manage both the storage and bandwidth of large volumes of IMINT data and also present results to analysts quickly. Lockheed Martin Advanced Technology Laboratories (ATL) has been actively researching in the area of applying Big Data cloud computing techniques to computer vision applications. This paper presents the results of this work in adopting a Lambda Architecture to process and disseminate IMINT data using computer vision algorithms. The approach embodies an end-to-end solution by processing IMINT data from sensors to serving information products quickly to analysts, independent of the size of the data. The solution lies in dividing up the architecture into a speed layer for low-latent processing and a batch layer for higher quality answers at the expense of time, but in a robust and fault-tolerant way. This approach was evaluated using a large corpus of IMINT data collected by a C-130 Shadow Harvest sensor over Afghanistan from 2010 through 2012. The evaluation data corpus included full motion video from both narrow and wide area field-of-views. The evaluation was done on a scaled-out cloud infrastructure that is similar in composition to those found in the Intelligence Community. The paper shows experimental results to prove the scalability of the architecture and precision of its results using a computer vision algorithm designed to identify man-made objects in sparse data terrain.

  12. Flight Tests of the KO-1 Aircraft at Night

    NASA Astrophysics Data System (ADS)

    Kwon, Jong-Kwang; Kim, Whan-Woo

    The KO-1 aircraft which has the functionality of tactical observation, was successfully developed in August of 2004 in South Korea. It is important for the KO-1 aircraft to achieve successful missions at nighttime as well as during daytime. The aircraft, equipped with interior and exterior lighting systems and lighting control panel modified from those of the KT-1 basic trainer, provides improved safety, operational effectiveness, and situational awareness during operation at night when used with night-vision goggles (NVGs). KO-1 is the first domestic aircraft that utilizes the night-vision imaging system (NVIS) technology in Korea. KO-1 NVIS was developed with the goal of defining the components of NVIS and establishing test and evaluation procedures for both the subsystems and main system. In this paper, we present the establishment of a KO-1 NVIS lighting system, NVIS component development, and representative ground and flight test results.

  13. Rotating waves during human sleep spindles organize global patterns of activity that repeat precisely through the night.

    PubMed

    Muller, Lyle; Piantoni, Giovanni; Koller, Dominik; Cash, Sydney S; Halgren, Eric; Sejnowski, Terrence J

    2016-11-15

    During sleep, the thalamus generates a characteristic pattern of transient, 11-15 Hz sleep spindle oscillations, which synchronize the cortex through large-scale thalamocortical loops. Spindles have been increasingly demonstrated to be critical for sleep-dependent consolidation of memory, but the specific neural mechanism for this process remains unclear. We show here that cortical spindles are spatiotemporally organized into circular wave-like patterns, organizing neuronal activity over tens of milliseconds, within the timescale for storing memories in large-scale networks across the cortex via spike-time dependent plasticity. These circular patterns repeat over hours of sleep with millisecond temporal precision, allowing reinforcement of the activity patterns through hundreds of reverberations. These results provide a novel mechanistic account for how global sleep oscillations and synaptic plasticity could strengthen networks distributed across the cortex to store coherent and integrated memories.

  14. Rotating waves during human sleep spindles organize global patterns of activity that repeat precisely through the night

    PubMed Central

    Muller, Lyle; Piantoni, Giovanni; Koller, Dominik; Cash, Sydney S; Halgren, Eric; Sejnowski, Terrence J

    2016-01-01

    During sleep, the thalamus generates a characteristic pattern of transient, 11-15 Hz sleep spindle oscillations, which synchronize the cortex through large-scale thalamocortical loops. Spindles have been increasingly demonstrated to be critical for sleep-dependent consolidation of memory, but the specific neural mechanism for this process remains unclear. We show here that cortical spindles are spatiotemporally organized into circular wave-like patterns, organizing neuronal activity over tens of milliseconds, within the timescale for storing memories in large-scale networks across the cortex via spike-time dependent plasticity. These circular patterns repeat over hours of sleep with millisecond temporal precision, allowing reinforcement of the activity patterns through hundreds of reverberations. These results provide a novel mechanistic account for how global sleep oscillations and synaptic plasticity could strengthen networks distributed across the cortex to store coherent and integrated memories. DOI: http://dx.doi.org/10.7554/eLife.17267.001 PMID:27855061

  15. Monooxygenase activity of black-crowned night-heron (BCNH) nestlings in Virginia, the Great Lakes and San Francisco Bay

    USGS Publications Warehouse

    Rattner, B.A.; Melancon, M.J.; Custer, T.W.; Hothem, R.L.; King, K.A.; LeCaptain, L.J.; Spann, J.W.

    1990-01-01

    To evaluate cytochrome P-450 related parameters as biomarkers of pollutant exposure, rates of arylhydrocarbon hydroxylase (AHH), ethoxyresorufin-O-deethylase (EROD), benzyloxyROD (BROD), pentoxyROD (PROD) and ethoxycoumarinOD (ECOD) were studied in 10-day-old BCNHs (Nycticorax nycticorax). Nestlings were collected from Chincoteague National Wildlife Refuge, VA ('controls') and from polluted sites including. Cat Island, Green Bay, WI, and Bair and West Marin Islands, San Francisco Bay, CA. Livers were frozen (-70.C) for monooxygenase assays and SDS-PAGE. Microsomal AHH and BROD activities were greater (P2 standard deviations from the control mean (induced up to 3-fold). EROD, PROD and ECOD did not differ among sites. Absence of an EROD response with AHH and BROD induction in BCNHs is different than responses in other species. The association of pollutant burdens with P-450 parameters is being studied. These biomarkers may serve as a rapid screen of exposure in a national contaminant biomonitoring program and other assessment activities.

  16. Development of Air Force aerial spray night operations: High altitude swath characterization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiple trials were conducted from 2006 to 2014 in an attempt to validate aerial spray efficacy at altitudes conducive to night spray operations using night vision goggles (NVG). Higher altitude application of pesticide (>400 feet above ground level [AGL]) suggested that effective vector control mi...

  17. How to assess vision.

    PubMed

    Marsden, Janet

    2016-09-21

    Rationale and key points An objective assessment of the patient's vision is important to assess variation from 'normal' vision in acute and community settings, to establish a baseline before examination and treatment in the emergency department, and to assess any changes during ophthalmic outpatient appointments. » Vision is one of the essential senses that permits people to make sense of the world. » Visual assessment does not only involve measuring central visual acuity, it also involves assessing the consequences of reduced vision. » Assessment of vision in children is crucial to identify issues that might affect vision and visual development, and to optimise lifelong vision. » Untreatable loss of vision is not an inevitable consequence of ageing. » Timely and repeated assessment of vision over life can reduce the incidence of falls, prevent injury and optimise independence. Reflective activity 'How to' articles can help update you practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How this article might change your practice when assessing people holistically. 2. How you could use this article to educate your colleagues in the assessment of vision.

  18. Active vision and image/video understanding with decision structures based on the network-symbolic models

    NASA Astrophysics Data System (ADS)

    Kuvich, Gary

    2003-08-01

    Vision is a part of a larger information system that converts visual information into knowledge structures. These structures drive vision process, resolve ambiguity and uncertainty via feedback projections, and provide image understanding that is an interpretation of visual information in terms of such knowledge models. The ability of human brain to emulate knowledge structures in the form of networks-symbolic models is found. And that means an important shift of paradigm in our knowledge about brain from neural networks to "cortical software". Symbols, predicates and grammars naturally emerge in such active multilevel hierarchical networks, and logic is simply a way of restructuring such models. Brain analyzes an image as a graph-type decision structure created via multilevel hierarchical compression of visual information. Mid-level vision processes like clustering, perceptual grouping, separation of figure from ground, are special kinds of graph/network transformations. They convert low-level image structure into the set of more abstract ones, which represent objects and visual scene, making them easy for analysis by higher-level knowledge structures. Higher-level vision phenomena are results of such analysis. Composition of network-symbolic models works similar to frames and agents, combines learning, classification, analogy together with higher-level model-based reasoning into a single framework. Such models do not require supercomputers. Based on such principles, and using methods of Computational intelligence, an Image Understanding system can convert images into the network-symbolic knowledge models, and effectively resolve uncertainty and ambiguity, providing unifying representation for perception and cognition. That allows creating new intelligent computer vision systems for robotic and defense industries.

  19. Object tracking with stereo vision

    NASA Technical Reports Server (NTRS)

    Huber, Eric

    1994-01-01

    A real-time active stereo vision system incorporating gaze control and task directed vision is described. Emphasis is placed on object tracking and object size and shape determination. Techniques include motion-centroid tracking, depth tracking, and contour tracking.

  20. Methods and Strategies: Math and Science Night

    ERIC Educational Resources Information Center

    Sullivan, Joan; Hatton, Mary

    2011-01-01

    Family Math and Science Nights engage students and parents in active investigations tied to the curriculum in a fun, informal environment. Through this program, families actively explore math and science ideas, discover together through guided inquiry, and apply their discoveries to solve a problem at the end. All activities are hands-on, use…

  1. Self-reported visual impairment and impact on vision-related activities in an elderly Nigerian population: report from the Ibadan Study of Ageing

    PubMed Central

    Bekibele, CO; Gureje, Oye

    2010-01-01

    Background Studies have shown an association between visual impairment and poor overall function. Studies from Africa and developing countries show high prevalence of visual impairment. More information is needed on the community prevalence and impact of visual impairment among elderly Africans. Methods A multi-stage stratified sampling of households was implemented to select persons aged 65 years and over in the south-western and north-central parts of Nigeria. Impairments of distant and near vision were based on subjective self-reports obtained with the use of items derived from the World Health Organization multi-country World Health Survey questionnaire. Impairment was defined as reporting much difficulty to questions on distant and near vision. Disabilities in activities of daily living (ADL) and instrumental activities of daily living (IADL) were evaluated by interview, using standardized scales. Results A total of 2054 subjects 957 (46.6%) males and 1097 (53.4) females responded to the questions on vision. 22% (n=453) of the respondents reported distant vision impairment, and 18% (n=377) reported near vision impairment (not mutually exclusive). 15% (n= 312) however reported impairment for both far and near vision. Impairment of distant vision increased progressively with age (P < 0.01). Persons with self reported near vision impairment had elevated risk of functional disability in several IADLs and ADLs than those with out. Distant vision impairment was less associated with role limitations in both ADLs and IADLs. Conclusion The prevalence of self reported distant visual impairment was high but that for near visual impairment was less than expected in this elderly African population. Impairment of near vision was found to carry with it a higher burden of functional disability than that of distant vision. PMID:18780258

  2. Emergency/Night Lightning

    NASA Astrophysics Data System (ADS)

    1980-01-01

    UDEC's highly efficient lighting system is finding wide acceptance among industrial and commercial firms as an energy savings means of providing emergency and night lighting. Originating from Skylab, the system consists of small high frequency fluorescent light fixtures powered by solar cells. Advantages of UDEC's lighting system stem from high reliability and high light output with very low energy drain. Principal components of system are long life fluorescent lamps operated by electronic circuitry, a sealed gelatine cell battery that needs no maintenance for eight years and a solid-state automatic battery charger. Installation of UDEC lighting in a company's six-and-a-half acre warehouse office cut the annual night lighting electric bill from 8,000 a year to 300 per year.

  3. Jupiter Night and Day

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Day and night side narrow angle images taken on January 1, 2001 illustrating storms visible on the day side which are the sources of visible lightning when viewed on the night side. The images have been enhanced in contrast. Note the two day-side occurrences of high clouds, in the upper and lower parts of the image, are coincident with lightning storms seen on the darkside. The storms occur at 34.5 degrees and 23.5 degrees North latitude, within one degree of the latitudes at which similar lightning features were detected by the Galileo spacecraft. The images were taken at different times. The storms' longitudinal separation changes from one image to the next because the winds carrying them blow at different speeds at the two latitudes.

  4. Emergency/Night Lightning

    NASA Technical Reports Server (NTRS)

    1980-01-01

    UDEC's highly efficient lighting system is finding wide acceptance among industrial and commercial firms as an energy savings means of providing emergency and night lighting. Originating from Skylab, the system consists of small high frequency fluorescent light fixtures powered by solar cells. Advantages of UDEC's lighting system stem from high reliability and high light output with very low energy drain. Principal components of system are long life fluorescent lamps operated by electronic circuitry, a sealed gelatine cell battery that needs no maintenance for eight years and a solid-state automatic battery charger. Installation of UDEC lighting in a company's six-and-a-half acre warehouse office cut the annual night lighting electric bill from $8,000 a year to $300 per year.

  5. Travelers In The Night

    NASA Astrophysics Data System (ADS)

    Grauer, Albert D.

    2014-11-01

    Travelers In The Night is an engaging and informative series of two minute radio programs about asteroids, comets, spacecraft, and other objects in space. The pieces are evergreen in that they are current but not dated. They are published on the Public Radio Exchange and carried by a number of radio stations. For teachers, students, and kids of all ages, the script for each piece and the start of a path for further inquiry can be found on the website travelersinthenight.org . The Travelers InThe Night Pieces are written and produced by an observing member of the Catalina Sky Survey Team at the University of Arizona. DPS members are encouraged to submit program ideas which can be developed to feature their research efforts.

  6. A Poet's Vision.

    ERIC Educational Resources Information Center

    Marshall, Suzanne; Newman, Dan

    1997-01-01

    Describes a series of activities to help middle school students develop an artist's vision and then convey that vision through poetry. Describes how lessons progress from looking at concrete objects to observations of settings and characters, gradually adding memory and imagination to direct observation, and finishing with revision. Notes that…

  7. Vision problems

    MedlinePlus

    ... shade or curtain hanging across part of your visual field. Optic neuritis : inflammation of the optic nerve ... Impaired vision; Blurred vision Images Crossed eyes Eye Visual acuity test Slit-lamp exam Visual field test ...

  8. Day, night and all-weather security surveillance automation synergy from combining two powerful technologies

    SciTech Connect

    Morellas, Vassilios; Johnson, Andrew; Johnston, Chris; Roberts, Sharon D.; Francisco, Glen L.

    2006-07-01

    Thermal imaging is rightfully a real-world technology proven to bring confidence to daytime, night-time and all weather security surveillance. Automatic image processing intrusion detection algorithms are also a real world technology proven to bring confidence to system surveillance security solutions. Together, day, night and all weather video imagery sensors and automated intrusion detection software systems create the real power to protect early against crime, providing real-time global homeland protection, rather than simply being able to monitor and record activities for post event analysis. These solutions, whether providing automatic security system surveillance at airports (to automatically detect unauthorized aircraft takeoff and landing activities) or at high risk private, public or government facilities (to automatically detect unauthorized people or vehicle intrusion activities) are on the move to provide end users the power to protect people, capital equipment and intellectual property against acts of vandalism and terrorism. As with any technology, infrared sensors and automatic image intrusion detection systems for global homeland security protection have clear technological strengths and limitations compared to other more common day and night vision technologies or more traditional manual man-in-the-loop intrusion detection security systems. This paper addresses these strength and limitation capabilities. False Alarm (FAR) and False Positive Rate (FPR) is an example of some of the key customer system acceptability metrics and Noise Equivalent Temperature Difference (NETD) and Minimum Resolvable Temperature are examples of some of the sensor level performance acceptability metrics. (authors)

  9. Small Boats in an Ocean of School Activities: Towards a European Vision on Education

    ERIC Educational Resources Information Center

    Villalba, Ernesto

    2008-01-01

    The paper discusses the concept of schools as "multi-purpose learning centres", proposed by the European Commission in the year 2000 as part of the Lisbon Strategy to improve competitiveness. This concept was arguably the "European vision" for school education and was meant to drive the modernization of school education.…

  10. Visualization of Whole-Night Sleep EEG From 2-Channel Mobile Recording Device Reveals Distinct Deep Sleep Stages with Differential Electrodermal Activity.

    PubMed

    Onton, Julie A; Kang, Dae Y; Coleman, Todd P

    2016-01-01

    Brain activity during sleep is a powerful marker of overall health, but sleep lab testing is prohibitively expensive and only indicated for major sleep disorders. This report demonstrates that mobile 2-channel in-home electroencephalogram (EEG) recording devices provided sufficient information to detect and visualize sleep EEG. Displaying whole-night sleep EEG in a spectral display allowed for quick assessment of general sleep stability, cycle lengths, stage lengths, dominant frequencies and other indices of sleep quality. By visualizing spectral data down to 0.1 Hz, a differentiation emerged between slow-wave sleep with dominant frequency between 0.1-1 Hz or 1-3 Hz, but rarely both. Thus, we present here the new designations, Hi and Lo Deep sleep, according to the frequency range with dominant power. Simultaneously recorded electrodermal activity (EDA) was primarily associated with Lo Deep and very rarely with Hi Deep or any other stage. Therefore, Hi and Lo Deep sleep appear to be physiologically distinct states that may serve unique functions during sleep. We developed an algorithm to classify five stages (Awake, Light, Hi Deep, Lo Deep and rapid eye movement (REM)) using a Hidden Markov Model (HMM), model fitting with the expectation-maximization (EM) algorithm, and estimation of the most likely sleep state sequence by the Viterbi algorithm. The resulting automatically generated sleep hypnogram can help clinicians interpret the spectral display and help researchers computationally quantify sleep stages across participants. In conclusion, this study demonstrates the feasibility of in-home sleep EEG collection, a rapid and informative sleep report format, and novel deep sleep designations accounting for spectral and physiological differences.

  11. Visualization of Whole-Night Sleep EEG From 2-Channel Mobile Recording Device Reveals Distinct Deep Sleep Stages with Differential Electrodermal Activity

    PubMed Central

    Onton, Julie A.; Kang, Dae Y.; Coleman, Todd P.

    2016-01-01

    Brain activity during sleep is a powerful marker of overall health, but sleep lab testing is prohibitively expensive and only indicated for major sleep disorders. This report demonstrates that mobile 2-channel in-home electroencephalogram (EEG) recording devices provided sufficient information to detect and visualize sleep EEG. Displaying whole-night sleep EEG in a spectral display allowed for quick assessment of general sleep stability, cycle lengths, stage lengths, dominant frequencies and other indices of sleep quality. By visualizing spectral data down to 0.1 Hz, a differentiation emerged between slow-wave sleep with dominant frequency between 0.1–1 Hz or 1–3 Hz, but rarely both. Thus, we present here the new designations, Hi and Lo Deep sleep, according to the frequency range with dominant power. Simultaneously recorded electrodermal activity (EDA) was primarily associated with Lo Deep and very rarely with Hi Deep or any other stage. Therefore, Hi and Lo Deep sleep appear to be physiologically distinct states that may serve unique functions during sleep. We developed an algorithm to classify five stages (Awake, Light, Hi Deep, Lo Deep and rapid eye movement (REM)) using a Hidden Markov Model (HMM), model fitting with the expectation-maximization (EM) algorithm, and estimation of the most likely sleep state sequence by the Viterbi algorithm. The resulting automatically generated sleep hypnogram can help clinicians interpret the spectral display and help researchers computationally quantify sleep stages across participants. In conclusion, this study demonstrates the feasibility of in-home sleep EEG collection, a rapid and informative sleep report format, and novel deep sleep designations accounting for spectral and physiological differences. PMID:27965558

  12. Is binocular vision worth considering in people with low vision?

    PubMed

    Uzdrowska, Marta; Crossland, Michael; Broniarczyk-Loba, Anna

    2014-01-01

    In someone with good vision, binocular vision provides benefits which could not be obtained by monocular viewing only. People with visual impairment often have abnormal binocularity. However, they often use both eyes simultaneously in their everyday activities. Much remains to be known about binocular vision in people with visual impairment. As the binocular status of people with low vision strongly influences their treatment and rehabilitation, it should be evaluated and considered before diagnosis and further recommendations.

  13. Low Vision Aids and Low Vision Rehabilitation

    MedlinePlus

    ... Vision Resources Low Vision Rehabilitation and Low Vision Aids Written by: David Turbert Edited by: Robert H ... covers most services, but not devices.) Low vision aids There are many low vision aids and devices ...

  14. Evaluation of Tactile Situation Awareness System as an Aid for Improving Aircraft Control During Periods of Impaired Vision

    DTIC Science & Technology

    2009-06-01

    Standardization NVG Night Vision Goggles OPNAVINST Operational Naval Instruction POM Program Objective Memorandum SEC Seconds TSAS Tactile...pioneering work of Dr. Rupert. The Netherlands used the TSAS in a study to reduce side drift while training pilots in the use of night vision ...H.A.H.C., Oving, A.B. (2002). Tactile Torso Display as Countermeasure to Reduce Night Vision Goggles Induced Drift, TNO Human Factors Soesterberg

  15. Vision and Motion Pictures.

    ERIC Educational Resources Information Center

    Grambo, Gregory

    1998-01-01

    Presents activities on persistence of vision that involve students in a hands-on approach to the study of early methods of creating motion pictures. Students construct flip books, a Zoetrope, and an early movie machine. (DDR)

  16. Night Side Jovian Aurora

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Jovian aurora on the night side of the planet. The upper bright arc is auroral emission seen 'edge on' above the planetary limb with the darkness of space as a background. The lower bright arc is seen against the dark clouds of Jupiter. The aurora is easier to see on the night side of Jupiter because it is fainter than the clouds when they are illuminated by sunlight. Jupiter's north pole is out of view to the upper right. The images were taken in the clear filter (visible light) and are displayed in shades of blue.

    As on Earth, the auroral emission is caused by electrically charged particles striking the upper atmosphere from above. The particles travel along the magnetic field lines of the planet, but their origin is not fully understood. The field lines where the aurora is most intense cross the Jovian equator at large distances (many Jovian radii) from the planet. The faint background throughout the image is scattered light in the camera. This stray light comes from the sunlit portion of Jupiter, which is out of the image to the right. In multispectral observations the aurora appears red, consistent with glow from atomic hydrogen in Jupiter's atmosphere. Galileo's unique perspective allows it to view the night side of the planet at short range, revealing details that cannot be seen from Earth. These detailed features are time dependent, and can be followed in sequences of Galileo images.

    North is at the top of the picture. A grid of planetocentric latitude and west longitude is overlain on the images. The images were taken on November 5, 1997 at a range of 1.3 million kilometers by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the

  17. Building Student Understanding of the Cause of Day and Night: A Study of Literacy- and Spatial Thinking-Integrated Activities Compared to a Commercial Curriculum

    ERIC Educational Resources Information Center

    Rule, Audrey C.; Webb, Angela Naomi

    2015-01-01

    The cause of day and night is a difficult concept to master without concrete foundational skills of understanding shadows, rotation, changing point of view, and relative positions of objects in the sky. This pretest-posttest experimental-control group study examined student learning in a science-literacy-spatial skills integrated unit with…

  18. Low Vision FAQs

    MedlinePlus

    ... USAJobs Home > Low Vision > Low Vision FAQs Healthy Vision Diabetes Diabetes Home How Much Do You Know? ... los Ojos Cómo hablarle a su oculista Low Vision FAQs What is low vision? Low vision is ...

  19. Dead of night.

    PubMed

    Balter, Leon

    2010-07-01

    Dead of Night, the first psychoanalytic horror film, was produced in England in 1945, immediately after the end of World War II--that is, after the English population had suffered systematic Nazi terror from imminent invasion, incessant aerial bombing, and rocket-bombs. This film continued the prewar format of horror films based on themes of the supernatural and the hubris and excesses of science. However, it introduced psychoanalysis as the science in question. The film is structured on two levels: a genteel English country weekend to which witty and urbane guests have been invited; and five horror stories told by the guests. Psychoanalytic insights into this film structure are used here to explain how the film induces horror in the audience.

  20. Strangers in the Night

    NASA Astrophysics Data System (ADS)

    McDonald, Gene D.

    Strangers in the Night was written by a father and son team, the elder of whom is a cosmochemist. Probably because of this view-point, the book makes a few novel points about the evolution of thinking on the origin of life and extraterrestrial life. A notable example is the mention of the first synthesis of a biological molecule (urea) by Freidrich Wohler in 1828, as one of the turning points in the gradual acceptance of the possibility of extraterrestrial life. Another high point in the book is the discussion of the other “life in meteorites” controversy the debate in the early 1960s concerning “organized elements” in carbonaceous chondrites. This chapter in the history of meteoritics is not very widely known and is highlighted with good cause by the authors as a stern warning about interpretation of possible biological structures in meteorites.

  1. [Blood transfusion practices: about transfusions at night].

    PubMed

    Roche, C; Théfenne, H; Hance, P; Garnotel, E

    2013-12-01

    Blood transfusion safety covers all stages from prescription of immuno-haematological examinations until the completion of the transfusion. According to the 05/11/2006 Afssaps' decision on good transfusion practices, transfusions should not be given at night unless the patient is actively bleeding or has some other urgent clinical need. A retrospective study was used to assess the proportion of transfusions at night. Through this professional practice evaluation, we analyze the reasons leading to perform transfusions at late hours, in order to reduce errors and improve safety for patients.

  2. Perception of difficulties with vision-related activities of daily living among patients undergoing unilateral posterior capsulotomy

    PubMed Central

    de Senne, Firmani M. B.; Temporini, Edméa R.; Arieta, Carlos E. L.; Pacheco, Karla D.

    2010-01-01

    OBJECTIVES To assess the influence of Nd:YAG (neodymium: yttrium-aluminum- garnet) laser unilateral posterior capsulotomy on visual acuity and patients’ perception of difficulties with vision-related activities of daily life. METHODS We conducted an interventional survey that included 48 patients between 40 and 80 years of age with uni- or bilateral pseudophakia, posterior capsule opacification, and visual acuity ≤0.30 (logMAR) in one eye who were seen at a Brazilian university hospital. All patients underwent posterior capsulotomy using an Nd:YAG laser. Before and after the intervention, patients were asked to complete a questionnaire that was developed in an exploratory study. RESULTS Before posterior capsulotomy, the median visual acuity (logMAR) of the included patients was 0.52 (range 0.30–1.60). After posterior capsulotomy, the median visual acuity of the included patients improved to 0.10 (range 0.0–0.52). According to the subjects’ perceptions, their ability to perform most of their daily life activities improved after the intervention (p<0.05). CONCLUSIONS After patients underwent posterior capsulotomy with an Nd:YAG laser, a significant improvement in the visual acuity of the treated eye was observed. Additionally, subjects felt that they experienced less difficulty performing most of their vision-dependent activities of daily living. PMID:20535363

  3. Visual acuity, color vision, and visual search performance at sea.

    PubMed

    Donderi, D C

    1994-03-01

    Visual acuity and color vision were tested during a search and rescue exercise at sea. Fifty-seven watchkeepers searched for orange and yellow life rafts during daylight and for lighted and unlighted life rafts at night with night vision goggles. There were 588 individual watches of one hour each. Measures of wind, waves, and weather were used as covariates. Daytime percentage detection was positively correlated with low-contrast visual acuity and negatively correlated with error scores on Dvorine pseudoisochromatic plates and the Farnsworth color test. Performance was better during the first half-hour of the watch. Efficiency calculations show that color vision selective screening at one standard deviation above the mean would increase daylight search performance by 10% and that one standard deviation visual acuity selection screening would increase performance by 12%. There was no relationship between either acuity or color vision and life raft detection using night vision goggles.

  4. Invite an Alien to Astronomy Night

    ERIC Educational Resources Information Center

    Governor, Donna; Richwine, Pebble

    2007-01-01

    Dozens of inflatable aliens recently "descended" upon the authors' middle school to kick-off their first school-wide Astronomy night. With an estimated attendance of over 500, their eighth-grade students hosted over a dozen activity-rich sessions designed to entertain and educate students and their families about the wonders of the solar system…

  5. Family Reading Night: A How to Guide

    ERIC Educational Resources Information Center

    Rehmer, Julie

    2007-01-01

    A family reading night is the ideal way to introduce the library media center and actively involve parents in their child's reading success. This event is an opportunity to explain how a reading program works and provide parents with strategies to encourage further reading at home. Parents can sit down with their children and read in the library,…

  6. Dynamically re-configurable CMOS imagers for an active vision system

    NASA Technical Reports Server (NTRS)

    Yang, Guang (Inventor); Pain, Bedabrata (Inventor)

    2005-01-01

    A vision system is disclosed. The system includes a pixel array, at least one multi-resolution window operation circuit, and a pixel averaging circuit. The pixel array has an array of pixels configured to receive light signals from an image having at least one tracking target. The multi-resolution window operation circuits are configured to process the image. Each of the multi-resolution window operation circuits processes each tracking target within a particular multi-resolution window. The pixel averaging circuit is configured to sample and average pixels within the particular multi-resolution window.

  7. Image Intensifiers, Night Vision (AN/PVS-7 Goggles)

    DTIC Science & Technology

    1985-07-11

    goggles as indi- cated by the chart for the set of lines observed in step d above. f. Repeat steps c , d, and e above illuminating the resolution...assembly 90 degrees in holder and repeat steps c through i. Record all readings on data sheet. k. Pick up this test when measuring the off-axis MTF

  8. Distance Estimation to Flashes in a Simulated Night Vision Environment

    DTIC Science & Technology

    2007-12-01

    Object recognition and contrast sensitivity with image intensifiers employing white phosphor versus green phosphor displays. Proceedings of SPIE - The...generation III model. NVGs are generally constructed using similar components. These components include the image intensifier tube, the objective lens, and...process of light amplification begins when the light photons reflect from surfaces in the environment and enter the objective lens. The image is

  9. Night Vision Laboratory Static Performance Model for Thermal Viewing Systems

    DTIC Science & Technology

    1975-04-01

    Electro-Science Laboratory, Columbus, Ohio, May 1968, AD 831666. 5:’ 4,0 L~IGT FOG - CLEAH TO Li-3HT HAZE 0.01 - VERY LL I CLEAR 0.5 1.0 2 34 63810 20...Next, note that for a simple imaging system Ii’Ad L 7r Ad2 LL () AT (49 where 77o(X) = the optical efficiency of the viewer F = the f/number T...CSeATV.CJNL NU AN2/ S:STPMUL) LL ,-km. PAGL f’JLL CS WAIT. CLEAR SCRN-EN, PRINT ’JANNE.R9 AND RETURN. CSIO CALL CUJNNEC(.5LIN1-UTs0) CS CALL CUNNLCCbL0UTPUTa0) C

  10. Thales Angenieux recent progress in night vision technology

    NASA Astrophysics Data System (ADS)

    Rollin, Joel; Teszner, Jean Louis; Espie, Jean-Luc

    2004-02-01

    Uncooled LWIR technology yields now an attractive alternative within the thermal sights area: TAGX launched one year ago, a new product line ELVIR, promoting cost-efficient solutions whilst meeting performances that are likely to suit most hand-held military purposes. We backed on our earnest skills on previous in-house made equipment such as light intensifier goggles, to reach the best trends, both complying with operational demands and current market prices. The very first step which is aiming at settling the main device characteristics will be emphasized thought typical requirements upon current customer"s requests: quick and flexible range computations models should answer that purpose and we will rely on operational feed back. ELVIR is built around micro- bolometer arrays that are available in France: a very best effort was done on each cost budget contributor, involving mechanics, electronics and optics. As detailed hereafter, many improvements were steered up by the latest research outcomes, partly sponsored by the French DGA, as, for instance, low cost LWIR lenses already off-the-shelves in France thanks to the UMICORE IR Glass Company. All these compromises will be displayed

  11. Evaluation of Night Vision Devices for Image Fusion Studies

    DTIC Science & Technology

    2004-12-01

    of the different NVDs. A new method using MATLAB programming to objectively analyze digitized images for characterization of II based NVDs is... MATLAB programming to objectively analyze digitized images for characterization of II based NVDs is proposed. This test method can also be extended to...75 APPENDIX A: ASTROSCOPE 9350 ANALYSIS RESULTS.......................... 77 APPENDIX B: MATLAB CODES

  12. Human Factors and Safety Considerations of Night Vision Systems Flight

    DTIC Science & Technology

    1989-07-01

    footlamberts. For cockpit lighting compatibility, the interior surfaces of the objective lenses of ANVIS are coated with a dielectric film (a minus-blue...exit pupil of the 12 NVD optics. Variations in head anthropometry and wearing protective mask or corrective lenses may prevent proper eye placement...A design solution to this problem is incorporated in the ANVIS. The interior surface of the objective lenses in the ANVIS have been coated with a

  13. Mild Hypoxia and Visual Performance with Night Vision Goggles

    DTIC Science & Technology

    1985-05-01

    21 5. Single - session data gathering .......................... 26 6. Performance without supplemental oxygen ................... 30 7...30 40 50 60 7 oz 0 CNNe M CD , 0 C 10 20 30 40 60 70 MINUTES Figure 5. Single - session data gathering. 27 Depletion of premixed gas required on-site

  14. Hunting in Bioluminescent Light: Vision in the Nocturnal Box Jellyfish Copula sivickisi

    PubMed Central

    Garm, Anders; Bielecki, Jan; Petie, Ronald; Nilsson, Dan-Eric

    2016-01-01

    Cubomedusae all have a similar set of six eyes on each of their four rhopalia. Still, there is a great variation in activity patterns with some species being strictly day active while others are strictly night active. Here we have examined the visual ecology of the medusa of the night active Copula sivickisi from Okinawa using optics, morphology, electrophysiology, and behavioral experiments. We found the lenses of both the upper and the lower lens eyes to be image forming but under-focused, resulting in low spatial resolution in the order of 10–15°. The photoreceptor physiology is similar in the two lens eyes and they have a single opsin peaking around 460 nm and low temporal resolution with a flicker fusion frequency (fff) of 2.5 Hz indicating adaptions to vision in low light intensities. Further, the outer segments have fluid filled swellings, which may concentrate the light in the photoreceptor membrane by total internal reflections, and thus enhance the signal to noise ratio in the eyes. Finally our behavioral experiments confirmed that the animals use vision when hunting. When they are active at night they seek out high prey-concentration by visual attraction to areas with abundant bioluminescent flashes triggered by their prey. PMID:27065877

  15. Vision without the Image

    PubMed Central

    Chen, Bo; Perona, Pietro

    2016-01-01

    Novel image sensors transduce the stream of photons directly into asynchronous electrical pulses, rather than forming an image. Classical approaches to vision start from a good quality image and therefore it is tempting to consider image reconstruction as a first step to image analysis. We propose that, instead, one should focus on the task at hand (e.g., detection, tracking or control) and design algorithms that compute the relevant variables (class, position, velocity) directly from the stream of photons. We discuss three examples of such computer vision algorithms and test them on simulated data from photon-counting sensors. Such algorithms work just-in-time, i.e., they complete classification, search and tracking with high accuracy as soon as the information is sufficient, which is typically before there are enough photons to form a high-quality image. We argue that this is particularly useful when the photons are few or expensive, e.g., in astronomy, biological imaging, surveillance and night vision. PMID:27058543

  16. Degradation of near infrared and shortwave infrared imager performance due to atmospheric scattering of diffuse night illumination.

    PubMed

    Vollmerhausen, Richard

    2013-07-20

    On moonless nights, airglow is the primary source of natural ground illumination in the near infrared and shortwave infrared spectral bands. Therefore, night vision imagers operating in these spectral bands view targets that are diffusely illuminated. Aerosol scattering of diffuse airglow illumination causes atmospheric path radiance and that radiance causes increased imager noise. These phenomena and their quantification are described in this paper.

  17. Computer vision

    NASA Technical Reports Server (NTRS)

    Gennery, D.; Cunningham, R.; Saund, E.; High, J.; Ruoff, C.

    1981-01-01

    The field of computer vision is surveyed and assessed, key research issues are identified, and possibilities for a future vision system are discussed. The problems of descriptions of two and three dimensional worlds are discussed. The representation of such features as texture, edges, curves, and corners are detailed. Recognition methods are described in which cross correlation coefficients are maximized or numerical values for a set of features are measured. Object tracking is discussed in terms of the robust matching algorithms that must be devised. Stereo vision, camera control and calibration, and the hardware and systems architecture are discussed.

  18. All Vision Impairment

    MedlinePlus

    ... Home > Statistics and Data > All Vision Impairment All Vision Impairment Vision Impairment Defined Vision impairment is defined as the ... Ethnicity 2010 U.S. Age-Specific Prevalence Rates for Vision Impairment by Age and Race/Ethnicity Table for ...

  19. Objectively measured night-to-night sleep variations are associated with body composition in very elderly women.

    PubMed

    Kim, Miji; Sasai, Hiroyuki; Kojima, Narumi; Kim, Hunkyung

    2015-12-01

    This cross-sectional study examined the association between objectively measured sleep patterns and body composition in very elderly community-dwelling women. Participants included 191 community-dwelling adults aged ≥ 80 years (mean age: 83.4 ± 2.6 years; age range: 80-92 years). Sleep and physical activity were monitored via accelerometer (ActiGraph GT3X+) during at least five consecutive 24-h periods. Night-to-night sleep pattern variability across all nights of recording was assessed using standard deviations (SDs). Body composition was assessed using dual-energy X-ray absorptiometry. Simple and multivariable linear regression analyses were performed. The mean number of nights with usable actigraphy data was 7.3 ± 1.3. On average, participants went to bed at 22:57 hours (SD: 1.11 h) and rose from bed at 6:27 hours (SD: 1.01 h). Night-to-night bedtime, sleep duration and sleep timing mid-point variations correlated slightly with the percentage body fat and percentage lean mass (P < 0.05). Multiple linear regression analysis revealed significant associations of night-to-night bedtime variations and inconsistent sleep-wake patterns with all body composition indices after adjusting for potential confounding factors, including mean nightly sleep duration, self-reported nap duration and daily physical activity. After further adjusting for night-to-night wake time, sleep timing mid-point and sleep duration variations, greater bedtime variability remained associated significantly with all body composition indices except lean/fat mass ratio. Inconsistent sleep-wake patterns were associated independently with an increased fat mass and decreased lean mass among very elderly women. These findings suggest that in most elderly individuals, sleep patterns might be an important modifiable factor associated with obesity and sarcopenia development.

  20. Improving Vision

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Many people are familiar with the popular science fiction series Star Trek: The Next Generation, a show featuring a blind character named Geordi La Forge, whose visor-like glasses enable him to see. What many people do not know is that a product very similar to Geordi's glasses is available to assist people with vision conditions, and a NASA engineer's expertise contributed to its development. The JORDY(trademark) (Joint Optical Reflective Display) device, designed and manufactured by a privately-held medical device company known as Enhanced Vision, enables people with low vision to read, write, and watch television. Low vision, which includes macular degeneration, diabetic retinopathy, and glaucoma, describes eyesight that is 20/70 or worse, and cannot be fully corrected with conventional glasses.

  1. Vision Underwater.

    ERIC Educational Resources Information Center

    Levine, Joseph S.

    1980-01-01

    Provides information regarding underwater vision. Includes a discussion of optically important interfaces, increased eye size of organisms at greater depths, visual peculiarities regarding the habitat of the coastal environment, and various pigment visual systems. (CS)

  2. [Central vision].

    PubMed

    Fahle, M

    2004-07-01

    The clinical assessment of vision by means of optotypes does by no means test just two-point resolution, since a correct naming of the letters or digits requires a preceding visual object recognition. Cortical lesions can massively deteriorate vision up to a "Seelenblindheit" in spite of intact optics and retina. There are different processing levels involved in the analysis which can be individually defective, leading to disorders from visual indiscrimination to agnosia or anomia.

  3. Retina-specific activation of a sustained hypoxia-like response leads to severe retinal degeneration and loss of vision.

    PubMed

    Lange, Christina; Caprara, Christian; Tanimoto, Naoyuki; Beck, Susanne; Huber, Gesine; Samardzija, Marijana; Seeliger, Mathias; Grimm, Christian

    2011-01-01

    Loss of vision and blindness in human patients is often caused by the degeneration of neuronal cells in the retina. In mouse models, photoreceptors can be protected from death by hypoxic preconditioning. Preconditioning in low oxygen stabilizes and activates hypoxia inducible transcription factors (HIFs), which play a major role in the hypoxic response of tissues including the retina. We show that a tissue-specific knockdown of von Hippel-Lindau protein (VHL) activated HIF transcription factors in normoxic conditions in the retina. Sustained activation of HIF1 and HIF2 was accompanied by persisting embryonic vasculatures in the posterior eye and the iris. Embryonic vessels persisted into adulthood and led to a severely abnormal mature vessel system with vessels penetrating the photoreceptor layer in adult mice. The sustained hypoxia-like response also activated the leukemia inhibitory factor (LIF)-controlled endogenous molecular cell survival pathway. However, this was not sufficient to protect the retina against massive cell death in all retinal layers of adult mice. Caspases 1, 3 and 8 were upregulated during the degeneration as were several VHL target genes connected to the extracellular matrix. Misregulation of these genes may influence retinal structure and may therefore facilitate growth of vessels into the photoreceptor layer. Thus, an early and sustained activation of a hypoxia-like response in retinal cells leads to abnormal vasculature and severe retinal degeneration in the adult mouse retina.

  4. The night before your surgery - children

    MedlinePlus

    Surgery - child; Preoperative - night before ... food after 11 p.m. the night before surgery. Your child should not eat or drink any ... child the night before or the day of surgery, call the doctor. Stop giving your child any ...

  5. Day, night, and all-weather security surveillance automation: synergy from combining two powerful technologies

    NASA Astrophysics Data System (ADS)

    Morellas, Vassilios; Johnston, Chris; Johnson, Andrew; Roberts, Sharon D.; Francisco, Glen L.

    2005-05-01

    Thermal imaging is rightfully a real-world technology proven to bring confidence to daytime, nighttime and all weather security surveillance. Automatic image processing intrusion detection algorithms are also a real world technology proven to bring confidence to system surveillance security solutions. Together, day, night and all weather video imagery sensors and automated intrusion detection software systems create the real power to protect early against crime, providing real-time global homeland protection, rather than simply being able to monitor and record activities for post event analysis. These solutions, whether providing automatic security system surveillance at airports (to automatically detect unauthorized aircraft takeoff and landing activities) or at high risk private, public or government facilities (to automatically detect unauthorized people or vehicle intrusion activities) are on the move to provide end users the power to protect people, capital equipment and intellectual property against acts of vandalism and terrorism. As with any technology, infrared sensors and automatic image intrusion detection systems for global homeland security protection have clear technological strengths and limitations compared to other more common day and night vision technologies or more traditional manual man-in-the-loop intrusion detection security systems. This paper addresses these strength and limitation capabilities. False Alarm (FAR) and False Positive Rate (FPR) is an example of some of the key customer system acceptability metrics and Noise Equivalent Temperature Difference (NETD) and Minimum Resolvable Temperature are examples of some of the sensor level performance acceptability metrics.

  6. Definition of display/control requirements for assault transport night/adverse weather capability

    NASA Technical Reports Server (NTRS)

    Milelli, R. J.; Mowery, G. W.; Pontelandolfo, C.

    1982-01-01

    A Helicopter Night Vision System was developed to improve low-altitude night and/or adverse weather assult transport capabilities. Man-in-the-loop simulation experiments were performed to define the minimum display and control requirements for the assult transport mission and investigate forward looking infrared sensor requirements, along with alternative displays such as panel mounted displays (PMD) helmet mounted displays (HMD), and integrated control display units. Also explored were navigation requirements, pilot/copilot interaction, and overall cockpit arrangement. Pilot use of an HMD and copilot use of a PMD appear as both the preferred and most effective night navigation combination.

  7. Congenital stationary night blindness in a Thoroughbred and a Paso Fino.

    PubMed

    Nunnery, Catherine; Pickett, J Phillip; Zimmerman, Kurt L

    2005-01-01

    This report documents congenital stationary night blindness (CSNB) in two non-Appaloosa horse breeds (Thoroughbred and Paso Fino). History of vision impairment since birth, normal ocular structures on ophthalmic examination, and electroretinographic findings were consistent with CSNB. In one horse (Thoroughbred), a 9-year follow-up was carried out. In the Paso Fino, severe vision impairment from birth to approximately 1 year of age in both dim and bright light situations led to humane euthanasia and histopathologic confirmation of the disorder.

  8. Vision-based aircraft guidance

    NASA Technical Reports Server (NTRS)

    Menon, P. K.

    1993-01-01

    Early research on the development of machine vision algorithms to serve as pilot aids in aircraft flight operations is discussed. The research is useful for synthesizing new cockpit instrumentation that can enhance flight safety and efficiency. With the present work as the basis, future research will produce low-cost instrument by integrating a conventional TV camera together with off-the=shelf digitizing hardware for flight test verification. Initial focus of the research will be on developing pilot aids for clear-night operations. Latter part of the research will examine synthetic vision issues for poor visibility flight operations. Both research efforts will contribute towards the high-speed civil transport aircraft program. It is anticipated that the research reported here will also produce pilot aids for conducting helicopter flight operations during emergency search and rescue. The primary emphasis of the present research effort is on near-term, flight demonstrable technologies. This report discusses pilot aids for night landing and takeoff and synthetic vision as an aid to low visibility landing.

  9. Artificial night lighting inhibits feeding in moths.

    PubMed

    van Langevelde, Frank; van Grunsven, Roy H A; Veenendaal, Elmar M; Fijen, Thijs P M

    2017-03-01

    One major, yet poorly studied, change in the environment is nocturnal light pollution, which strongly alters habitats of nocturnally active species. Artificial night lighting is often considered as driving force behind rapid moth population declines in severely illuminated countries. To understand these declines, the question remains whether artificial light causes only increased mortality or also sublethal effects. We show that moths subjected to artificial night lighting spend less time feeding than moths in darkness, with the shortest time under light conditions rich in short wavelength radiation. These findings provide evidence for sublethal effects contributing to moth population declines. Because effects are strong under various types of light compared with dark conditions, the potential of spectral alterations as a conservation tool may be overestimated. Therefore, restoration and maintenance of darkness in illuminated areas is essential for reversing declines of moth populations.

  10. Ultraviolet vision may be widespread in bats

    USGS Publications Warehouse

    Gorresen, P. Marcos; Cryan, Paul; Dalton, David C.; Wolf, Sandy; Bonaccorso, Frank

    2015-01-01

    Insectivorous bats are well known for their abilities to find and pursue flying insect prey at close range using echolocation, but they also rely heavily on vision. For example, at night bats use vision to orient across landscapes, avoid large obstacles, and locate roosts. Although lacking sharp visual acuity, the eyes of bats evolved to function at very low levels of illumination. Recent evidence based on genetics, immunohistochemistry, and laboratory behavioral trials indicated that many bats can see ultraviolet light (UV), at least at illumination levels similar to or brighter than those before twilight. Despite this growing evidence for potentially widespread UV vision in bats, the prevalence of UV vision among bats remains unknown and has not been studied outside of the laboratory. We used a Y-maze to test whether wild-caught bats could see reflected UV light and whether such UV vision functions at the dim lighting conditions typically experienced by night-flying bats. Seven insectivorous species of bats, representing five genera and three families, showed a statistically significant ‘escape-toward-the-light’ behavior when placed in the Y-maze. Our results provide compelling evidence of widespread dim-light UV vision in bats.

  11. Night airglow in RGB mode

    NASA Astrophysics Data System (ADS)

    Mikhalev, Aleksandr; Podlesny, Stepan; Stoeva, Penka

    2016-09-01

    To study dynamics of the upper atmosphere, we consider results of the night sky photometry, using a color CCD camera and taking into account the night airglow and features of its spectral composition. We use night airglow observations for 2010-2015, which have been obtained at the ISTP SB RAS Geophysical Observatory (52° N, 103° E) by the camera with KODAK KAI-11002 CCD sensor. We estimate the average brightness of the night sky in R, G, B channels of the color camera for eastern Siberia with typical values ranging from ~0.008 to 0.01 erg*cm-2*s-1. Besides, we determine seasonal variations in the night sky luminosities in R, G, B channels of the color camera. In these channels, luminosities decrease in spring, increase in autumn, and have a pronounced summer maximum, which can be explained by scattered light and is associated with the location of the Geophysical Observatory. We consider geophysical phenomena with their optical effects in R, G, B channels of the color camera. For some geophysical phenomena (geomagnetic storms, sudden stratospheric warmings), we demonstrate the possibility of the quantitative relationship between enhanced signals in R and G channels and increases in intensities of discrete 557.7 and 630 nm emissions, which are predominant in the airglow spectrum.

  12. Community Vision and Interagency Alignment: A Community Planning Process to Promote Active Transportation.

    PubMed

    DeGregory, Sarah Timmins; Chaudhury, Nupur; Kennedy, Patrick; Noyes, Philip; Maybank, Aletha

    2016-04-01

    In 2010, the Brooklyn Active Transportation Community Planning Initiative launched in 2 New York City neighborhoods. Over a 2-year planning period, residents participated in surveys, school and community forums, neighborhood street assessments, and activation events-activities that highlighted the need for safer streets locally. Consensus among residents and key multisectoral stakeholders, including city agencies and community-based organizations, was garnered in support of a planned expansion of bicycling infrastructure. The process of building on community assets and applying a collective impact approach yielded changes in the built environment, attracted new partners and resources, and helped to restore a sense of power among residents.

  13. When a photograph can be heard: vision activates the auditory cortex within 110 ms.

    PubMed

    Proverbio, Alice Mado; D'Aniello, Guido Edoardo; Adorni, Roberta; Zani, Alberto

    2011-01-01

    As the makers of silent movies knew well, it is not necessary to provide an actual auditory stimulus to activate the sensation of sounds typically associated with what we are viewing. Thus, you could almost hear the neigh of Rodolfo Valentino's horse, even though the film was mute. Evidence is provided that the mere sight of a photograph associated with a sound can activate the associative auditory cortex. High-density ERPs were recorded in 15 participants while they viewed hundreds of perceptually matched images that were associated (or not) with a given sound. Sound stimuli were discriminated from non-sound stimuli as early as 110 ms. SwLORETA reconstructions showed common activation of ventral stream areas for both types of stimuli and of the associative temporal cortex, at the earliest stage, only for sound stimuli. The primary auditory cortex (BA41) was also activated by sound images after approximately 200 ms.

  14. Vision by Man and Machine.

    ERIC Educational Resources Information Center

    Poggio, Tomaso

    1984-01-01

    Studies of stereo vision guide research on how animals see and how computers might accomplish this human activity. Discusses a sequence of algorithms to first extract information from visual images and then to calculate the depths of objects in the three-dimensional world, concentrating on stereopsis (stereo vision). (JN)

  15. Night Myopia Studied with an Adaptive Optics Visual Analyzer

    PubMed Central

    Artal, Pablo; Schwarz, Christina; Cánovas, Carmen; Mira-Agudelo, Alejandro

    2012-01-01

    Purpose Eyes with distant objects in focus in daylight are thought to become myopic in dim light. This phenomenon, often called “night myopia” has been studied extensively for several decades. However, despite its general acceptance, its magnitude and causes are still controversial. A series of experiments were performed to understand night myopia in greater detail. Methods We used an adaptive optics instrument operating in invisible infrared light to elucidate the actual magnitude of night myopia and its main causes. The experimental setup allowed the manipulation of the eye's aberrations (and particularly spherical aberration) as well as the use of monochromatic and polychromatic stimuli. Eight subjects with normal vision monocularly determined their best focus position subjectively for a Maltese cross stimulus at different levels of luminance, from the baseline condition of 20 cd/m2 to the lowest luminance of 22×10−6 cd/m2. While subjects performed the focusing tasks, their eye's defocus and aberrations were continuously measured with the 1050-nm Hartmann-Shack sensor incorporated in the adaptive optics instrument. The experiment was repeated for a variety of controlled conditions incorporating specific aberrations of the eye and chromatic content of the stimuli. Results We found large inter-subject variability and an average of −0.8 D myopic shift for low light conditions. The main cause responsible for night myopia was the accommodation shift occurring at low light levels. Other factors, traditionally suggested to explain night myopia, such as chromatic and spherical aberrations, have a much smaller effect in this mechanism. Conclusions An adaptive optics visual analyzer was applied to study the phenomenon of night myopia. We found that the defocus shift occurring in dim light is mainly due to accommodation errors. PMID:22768343

  16. TWAN: The World at Night

    NASA Astrophysics Data System (ADS)

    Tafreshi, Babak A.

    2011-06-01

    The World at Night (TWAN) is a global program to produce, collect, and present stunning photographs and time-lapse videos of the world's most beautiful and historic sites against the night-time backdrop of stars, planets, and celestial events. TWAN is a bridge between art, science and humanity to bring the message of peace, concealed in the sky. Organised by ``Astronomers Without Borders'', the project consist of world's best night sky photographers in over countries and coordinators, regional event organisers, and consultants. TWAN was also designated as a Special Project of the International Year of Astronomy 2009. While the project's global exhibitions and educational events peaked during IYA2009, TWAN is planned for long term in several phases and will continue to create and exhibit images in the next years.

  17. Presidential Visions.

    ERIC Educational Resources Information Center

    Gallin, Alice, Ed.

    1992-01-01

    This journal issue is devoted to the theme of university presidents and their visions of the future. It presents the inaugural addresses and speeches of 16 Catholic college and university presidents focusing on their goals, ambitions, and reasons for choosing to become higher education leaders at this particular time in the history of education in…

  18. Visions 2001.

    ERIC Educational Resources Information Center

    Rivero, Victor; Norman, Michele

    2001-01-01

    Reports on the views of 18 educational leaders regarding their vision on the future of education in an information age. Topics include people's diverse needs; relationships between morality, ethics, values, and technology; leadership; parental involvement; online courses from multiple higher education institutions; teachers' role; technology…

  19. Night Blindness and Ancient Remedy

    PubMed Central

    Al Binali, H.A. Hajar

    2014-01-01

    The aim of this article is to briefly review the history of night blindness and its treatment from ancient times until the present. The old Egyptians, the Babylonians, the Greeks and the Arabs used animal liver for treatment and successfully cured the disease. The author had the opportunity to observe the application of the old remedy to a patient. Now we know what the ancients did not know, that night blindness is caused by Vitamin A deficiency and the animal liver is the store house for Vitamin A. PMID:25774260

  20. Healthy Vision Tips

    MedlinePlus

    ... NEI for Kids > Healthy Vision Tips All About Vision About the Eye Ask a Scientist Video Series ... Links to More Information Optical Illusions Printables Healthy Vision Tips Healthy vision starts with you! Use these ...

  1. Blindness and vision loss

    MedlinePlus

    ... eye ( chemical burns or sports injuries) Diabetes Glaucoma Macular degeneration The type of partial vision loss may differ, ... tunnel vision and missing areas of vision With macular degeneration, the side vision is normal but the central ...

  2. Girls' Sports and Physical Activities in the Community: An Inclusive Vision for the New Millennium.

    ERIC Educational Resources Information Center

    Varpalotai, Aniko; Doherty, Alison

    The Gender Equity in Recreation Services Policy for the City of London (Ontario, Canada, November 1996) was the first municipal policy of its kind in Canada. It followed the development of the Sport Canada Policy on Women in Sport and the Ontario Policy on Full and Fair Access for Women and Girls in Sport and Physical Activity. It resulted from…

  3. Colour, vision and ergonomics.

    PubMed

    Pinheiro, Cristina; da Silva, Fernando Moreira

    2012-01-01

    This paper is based on a research project - Visual Communication and Inclusive Design-Colour, Legibility and Aged Vision, developed at the Faculty of Architecture of Lisbon. The research has the aim of determining specific design principles to be applied to visual communication design (printed) objects, in order to be easily read and perceived by all. This study target group was composed by a selection of socially active individuals, between 55 and 80 years, and we used cultural events posters as objects of study and observation. The main objective is to overlap the study of areas such as colour, vision, older people's colour vision, ergonomics, chromatic contrasts, typography and legibility. In the end we will produce a manual with guidelines and information to apply scientific knowledge into the communication design projectual practice. Within the normal aging process, visual functions gradually decline; the quality of vision worsens, colour vision and contrast sensitivity are also affected. As people's needs change along with age, design should help people and communities, and improve life quality in the present. Applying principles of visually accessible design and ergonomics, the printed design objects, (or interior spaces, urban environments, products, signage and all kinds of visually information) will be effective, easier on everyone's eyes not only for visually impaired people but also for all of us as we age.

  4. Inconsolable night-time awakening: beyond night terrors.

    PubMed

    Snyder, David M; Goodlin-Jones, Beth L; Pionk, Mary Jane; Stein, Martin T

    2008-08-01

    Sophia is a 3-year-old girl who was brought to her pediatrician by her parents who were concerned about inconsolable night-time awakening. Her mother indicated that she has frequent (>6), early nocturnal awakenings accompanied by screaming and crying lasting up to 1 hour since her birth. These episodes increased in intensity and frequency in the past year since the birth of her brother. With a bedtime routine (a cup of water by bedside with a washcloth and touching mother's nose, chin, and cheeks), Sophia falls asleep easily; however, within 1 hour she awakes screaming and flailing unaware of her surroundings and unable to be comforted. There are no tonic-clonic movements. Prior interventions, including a sleep coach and "letting Sophia cry it out," did not change her sleep pattern. Sophia's mother reports that she needs to be on a specific daily routine including set times for awakening, activity, snacks, naps, and meals. Diversion from the routine and separation from her mother results in a tantrum (kicking, hitting, screaming, and inconsolability) often lasting more than 30 minutes. Sophia was born after an uncomplicated 37-week gestation. Neonatal hyperbilirubinemia required readmission for 24 hours of phototherapy; serum bilirubin levels were performed daily for 3 weeks after discharge. At 6 weeks, daily episodes of screaming, inconsolability, forceful vomiting, and inability to sleep led to a diagnosis of gastroesophageal reflux. Medication trials were not successful, but the symptoms resolved by 5 months. Formula intolerance and difficulty swallowing and chewing different textures of solid food occurred in the first year. Occupational therapy was of "no benefit"; Sophia was overwhelmed by the activity and took a long time to warm up to the therapist. Her texture aversion resolved by 2 years of age. She prefers one-on-one play and has minimal interactions with other children. She has met all her developmental milestones appropriately and has no other health

  5. Low night temperature acclimation of Phalaenopsis.

    PubMed

    Pollet, Bruno; Vanhaecke, Lynn; Dambre, Pieter; Lootens, Peter; Steppe, Kathy

    2011-06-01

    The capability of Phalaenopsis to acclimate its photosynthetic capacity and metabolic activity to cool night temperature conditions is crucial for improving orchid production in terms of efficient greenhouse heating. The extent to which Phalaenopsis possesses acclimation potential and the mechanistic background of the metabolic processes involved, have, however, not been studied before. Plants were subjected to a direct and gradual shift from a day to night temperature regime of 28/28-28/16°C, the cold stress and cold acclimation treatment, respectively. In comparison with the cold stress treatment, the cold acclimation treatment led to a higher malate accumulation and a reduction in leaf net CO(2) uptake. Consistently, the contribution of respiratory CO(2) recycling to nocturnal malate synthesis was calculated to be 23.5 and 47.0% for the cold stress and cold acclimation treatment, respectively. Moreover, the lower levels of starch measured in the cold acclimated leaves confirmed the suggested enhanced respiratory CO(2) recycling, implying that Phalaenopsis CAM operation evolved towards CAM idling. It is, however, plausible that this adjustment was not an effect of the low night temperature per se but a consequence of cool-root induced drought stress. Apart from that, at the start of the photoperiod, membrane stability showed a depression which was directly counteracted by an increased generation of glucose, fructose and sucrose. From these observations, it can be concluded that the observed plasticity in CAM operation and metabolic flexibility may be recognized as important steps in the low night temperature acclimation of Phalaenopsis.

  6. TrkB Activators for the Treatment of Traumatic Vision Loss

    DTIC Science & Technology

    2015-10-01

    receptor for brain -derived neurotrophic factor (BDNF). BDNF has been shown to have neuroprotective effects in a number of degeneration models ...4 HIOC has also demonstrated protective activity in an animal model for light-induced retinal degeneration, and can pass the blood- brain and blood...14. ABSTRACT Pressure waves due to explosions can damage the neurons of the eye and visual centers in the brain , leading to functional loss of

  7. Optical correction and quality of vision of the French soldiers stationed in the Republic of Djibouti in 2009.

    PubMed

    Vignal, Rodolphe; Ollivier, Lénaïck

    2011-03-01

    To ensure vision readiness on the battlefield, the French military has been providing its soldiers with eyewear since World War I. A military refractive surgery program was initiated in 2008. A prospective questionnaire-based investigation on optical correction and quality of vision among active duty members with visual deficiencies stationed in Djibouti, Africa, was conducted in 2009. It revealed that 59.3% of the soldiers were wearing spectacles, 21.2% were wearing contact lenses--despite official recommendations--and 8.5% had undergone refractive surgery. Satisfaction rates were high with refractive surgery and contact lenses; 33.6% of eyeglass wearers were planning to have surgery. Eye dryness and night vision disturbances were the most reported symptoms following surgery. Military optical devices were under-prescribed before deployment. This suggests that additional and more effective studies on the use of military optical devices should be performed and policy supporting refractive surgery in military populations should be strengthened.

  8. Present Vision--Future Vision.

    ERIC Educational Resources Information Center

    Fitterman, L. Jeffrey

    This paper addresses issues of current and future technology use for and by individuals with visual impairments and blindness in Florida. Present technology applications used in vision programs in Florida are individually described, including video enlarging, speech output, large inkprint, braille print, paperless braille, and tactual output…

  9. Night Operations - The Soviet Approach

    DTIC Science & Technology

    1978-06-09

    Battle of Berlin reveal the purpose for the night tactic of il- * ilumination : surprise and psychological impact, both on the enemy and friendly forces. An...attack Ilumination by shell Tn in k* Illumination by flare a Tank In firing position Observation post Antitank missle in firing position APC C3 APC

  10. Shedding Light on Light Pollution: Reports from GLOBE at Night

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.; Pompea, S. M.; Isbell, D.

    2009-05-01

    The citizen-science program on light pollution, GLOBE at Night, has had rich responses during this year's campaign in March 2009. Reporting on some of the highlights, we will hear success stories and lessons learned from educators, students, science centers and astronomy clubs from around the world. Communities will be featured from several cities, such Norman, Oklahoma, Mishawaka, Indiana, Willimantic, Connecticut, and Waynesville, Ohio, which created mini-campaigns that combined local students with public advocates and representatives from local city and county governments. Connecticut kids collaborated with students in Wales, Canada and Romania on GLOBE at Night, and an extensive campaign was planned with the schools near the observatories of north-central Chile. Groups that have received special training in GLOBE at Night and related activities include the "Astronomy from the Ground Up” network of science and nature centers (fostered by the ASP and the NSF), 146 amateur astronomers who are part of the ASP-NASA Night-Sky Network, and the Association of Science-Technology Centers. Special training was given over forums, telecon-powerpoint presentations and blogs, to fit the needs of the communities. Among the more interesting media efforts for the general public, GLOBE at Night was the topic of the March 6 episode of the IYA2009 "Days of Astronomy" podcast. International organizing efforts for GLOBE at Night have been strong in countries like Argentina, Australia, Austria, Brazil, Canada, Chile, Costa Rica, the Czech Republic, Germany, Hungary, Ireland, Poland, Portugal, Romania, Spain and the United Kingdom, to name a few. We will also discuss how cities, such as Tucson, Arizona, combined efforts on GLOBE at Night with involvement in the World Wildlife Fund's Earth Hour event (www.earthhour.org). Earth Hour encouraged everyone to turn out their lights from 8:30-9:30 p.m. local time on Saturday, March 28, the final night of GLOBE at Night 2009.

  11. Computer vision

    SciTech Connect

    Not Available

    1982-01-01

    This paper discusses material from areas such as artificial intelligence, psychology, computer graphics, and image processing. The intent is to assemble a selection of this material in a form that will serve both as a senior/graduate-level academic text and as a useful reference to those building vision systems. This book has a strong artificial intelligence flavour, emphasising the belief that both the intrinsic image information and the internal model of the world are important in successful vision systems. The book is organised into four parts, based on descriptions of objects at four different levels of abstraction. These are: generalised images-images and image-like entities; segmented images-images organised into subimages that are likely to correspond to interesting objects; geometric structures-quantitative models of image and world structures; relational structures-complex symbolic descriptions of image and world structures. The book contains author and subject indexes.

  12. A Chang'e-4 mission concept and vision of future Chinese lunar exploration activities

    NASA Astrophysics Data System (ADS)

    Wang, Qiong; Liu, Jizhong

    2016-10-01

    A novel concept for Chinese Chang'e-4 lunar exploration mission is presented in this paper at first. After the success of Chang'e-3, its backup probe, Chang'e-4 lander/rover combination, would be upgraded and land on the unexplored lunar farside by the aid of a relay satellite near the second Earth-Moon Lagrange point. Mineralogical and geochemical surveys on the farside to study the formation and evolution of lunar crust and observations at low radio frequencies to track the signals of the Universe's Dark Ages are priorities. Follow-up Chinese lunar exploration activities before 2030 are envisioned as building a robotic lunar science station by three to five missions. Finally several methods of international cooperation are proposed.

  13. Cartesian visions.

    PubMed

    Fara, Patricia

    2008-12-01

    Few original portraits exist of René Descartes, yet his theories of vision were central to Enlightenment thought. French philosophers combined his emphasis on sight with the English approach of insisting that ideas are not innate, but must be built up from experience. In particular, Denis Diderot criticised Descartes's views by describing how Nicholas Saunderson--a blind physics professor at Cambridge--relied on touch. Diderot also made Saunderson the mouthpiece for some heretical arguments against the existence of God.

  14. Machine vision

    SciTech Connect

    Horn, D.

    1989-06-01

    To keep up with the speeds of modern production lines, most machine vision applications require very powerful computers (often parallel-processing machines), which process millions of points of data in real time. The human brain performs approximately 100 billion logical floating-point operations each second. That is 400 times the speed of a Cray-1 supercomputer. The right software must be developed for parallel-processing computers. The NSF has awarded Rensselaer Polytechnic Institute (Troy, N.Y.) a $2 million grant for parallel- and image-processing software research. Over the last 15 years, Rensselaer has been conducting image-processing research, including work with high-definition TV (HDTV) and image coding and understanding. A similar NSF grant has been awarded to Michigan State University (East Lansing, Mich.) Neural networks are supposed to emulate human learning patterns. These networks and their hardware implementations (neurocomputers) show a great deal of promise for machine vision systems because they allow the systems to understand the use sensory data input more effectively. Neurocomputers excel at pattern-recognition tasks when input data are fuzzy or the vision algorithm is not optimal and is difficult to ascertain.

  15. Light Pollution Awareness through Globe at Night & IYL2015

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.

    2015-01-01

    The International Astronomical Union (IAU) will be coordinating extensive activities to raise awareness of light pollution through running the Cosmic Light theme of the International Year of Light (IYL2015) and by partnering in particular with the popular Globe at Night program.Globe at Night (www.globeatnight.org) is an international campaign to raise public awareness of the impact of light pollution by having people measure night-sky brightness and submit observations in real-time with smart phone or later with a computer. In 2015, Globe at Night will run for 10-nights each month, an hour after sunset til before the Moon rises. Students can use the data to monitor levels of light pollution around the world, as well as understand light pollution's effects on energy consumption, plants, wildlife, human health and our ability to enjoy a starry night sky.Since its inception in 2006, more than 115,000 measurements from 115 countries have been reported. The last 9 years of data can be explored with Globe at Night's interactive world map or with the 'map app' to view a particular area. A spreadsheet of the data is downloadable from any year. One can compare Globe at Night data with a variety of other databases to see, for example, how light pollution affects the foraging habits of bats.To encourage public participation in Globe at Night during IYL2015, each month will target an area of the world that habitually contributes during that time. Special concerns for how light pollution affects that area and solutions will be featured on the Globe at Night website (www.globeatnight.org), through its Facebook page, in its newsletter or in the 365DaysofAstronomy.org podcasts.Twice during IYL there will be a global Flash Mob event, one on Super Pi Day (March 14, 2015) and a second in mid-September, where the public will be invited to take night-sky brightness measurements en masse. In April, the International Dark-Sky Week hosted by the International Dark-Sky Association will be

  16. Simplified night sky display system

    NASA Technical Reports Server (NTRS)

    Castellano, Timothy P. (Inventor)

    2008-01-01

    A portable structure, simply constructed with inexpensive and generally lightweight materials, for displaying a selected portion of the night sky and selected planets, satellites, comets and other astronomically observable objects that are visually perceptible within that portion of the night sky. The structure includes a computer having stored signals representing the observable objects, an image projector that converts and projects the stored signals as visually perceptible images, a first curvilinear light-reflecting surface to receive and reflect the visually perceptible images, and a second curvilinear surface to receive and display the visually perceptible images reflected from the first surface. The images may be motionless or may move with passage of time. In one embodiment, the structure includes an inflatable screen surface that receives gas in an enclosed volume, supports itself without further mechanical support, and optionally self-regulates pressure of the received gas within the enclosed volume.

  17. Tips for Getting a Good Night's Sleep

    MedlinePlus

    ... of this page please turn JavaScript on. Feature: Sleep Disorders Tips for Getting A Good Night's Sleep Past ... in bed at night, you may have a sleep disorder. Your family healthcare provider or a sleep specialist ...

  18. Hot Flashes amd Night Sweats (PDQ)

    MedlinePlus

    ... Professionals Questions to Ask about Your Treatment Research Hot Flashes and Night Sweats (PDQ®)–Patient Version Overview ... quality of life in many patients with cancer. Hot flashes and night sweats may be side effects ...

  19. Low-cost day/night helmet-mounted displays (HMD) in airborne operations

    NASA Astrophysics Data System (ADS)

    Casey, Curtis J.

    1999-07-01

    Current doctrine dictates a requirement for conducting 24-hour operations on the modern battlefield either in a rural or urban environment. To date, Night Vision Goggles (NVGs) along with Infrared sensors provide the bulk of vision aids that allow crew members to engage in tactical operations at night and during periods of low and reduced visibility. Since operations employing these devices, as well as operational doctrine, require the crewmember to fly 'heads-out,' Heads-Up Displays (HUDs), enumerating flight parameters, engine and navigation information have come into existence, greatly reducing the workload on today's combat aviators. A fine example is the Marconi/Tracor ANVS-7. This device employs a symbol generator and CRT to project symbology of critical aircraft parameters into the Night Vision Goggle giving the aviator a HUD capability while engaged in NVG night operations. The system is limited to aided vision night operations employing NVGs. The same criteria that create a need for supplying critical flight information at night exist for day and night unaided vision operations. However, there is no system in production to answer this obvious need. There are several reasons for this: (1) Available technology that will offer a low-cost solution for days ops, (2) Ergonomic and Human factors Issues, (3) Competition with currently fielded systems (ANVS-7), (4) Cost. Highly sophisticated HMDs such as the Apache IHADSS and the Comanche HIDSS, which combine navigation, targeting as well as weapons and flight status for 24 hour, all-weather operations are far too expensive and, in many cases, inappropriate for the majority of Combat Support aircraft. Using internal R&D Kaiser Electronics has developed a low-cost HMD -- called Lite EyeTM HMD -- that is capable of being used in day and night operations that addresses the aforementioned issues. The solution, using recent advances in solid state display technology, maximizes the use of currently fielded equipment

  20. Night Sky Brightness at San Pedro Martir Observatory

    NASA Astrophysics Data System (ADS)

    Plauchu-Frayn, I.; Richer, M. G.; Colorado, E.; Herrera, J.; Córdova, A.; Ceseña, U.; Ávila, F.

    2017-03-01

    We present optical UBVRI zenith night sky brightness measurements collected on 18 nights during 2013 to 2016 and SQM measurements obtained daily over 20 months during 2014 to 2016 at the Observatorio Astronómico Nacional on the Sierra San Pedro Mártir (OAN-SPM) in México. The UBVRI data is based upon CCD images obtained with the 0.84 m and 2.12 m telescopes, while the SQM data is obtained with a high-sensitivity, low-cost photometer. The typical moonless night sky brightness at zenith averaged over the whole period is U = 22.68, B = 23.10, V = 21.84, R = 21.04, I = 19.36, and SQM = 21.88 {mag} {{arcsec}}-2, once corrected for zodiacal light. We find no seasonal variation of the night sky brightness measured with the SQM. The typical night sky brightness values found at OAN-SPM are similar to those reported for other astronomical dark sites at a similar phase of the solar cycle. We find a trend of decreasing night sky brightness with decreasing solar activity during period of the observations. This trend implies that the sky has become darker by Δ U = 0.7, Δ B = 0.5, Δ V = 0.3, Δ R=0.5 mag arcsec‑2 since early 2014 due to the present solar cycle.

  1. Activating a Vision

    ERIC Educational Resources Information Center

    Wilson, Carroll L.

    1973-01-01

    International Center of Insect Physiology and Ecology (ICIPE) is an organized effort to study physiology, endocrinology, genetics, and related processes of five insects. Location of the center in Kenya encourages developing countries to conduct research for the control of harmful insects. (PS)

  2. Psychotherapy with night-terror patients.

    PubMed

    Kales, J C; Cadieux, R J; Soldatos, C R; Kales, A

    1982-07-01

    This is the first report of the effectiveness of psychotherapy in treating adult night-terror patients. Night terrors were eliminated or drastically reduced in two patients who completed psychotherapy. A third patient discontinued therapy and showed no improvement. Thus, the primary role of psychopathology in the production of night terrors in adulthood was illustrated.

  3. Vision Therapy News Backgrounder.

    ERIC Educational Resources Information Center

    American Optometric Association, St. Louis, MO.

    The booklet provides an overview on vision therapy to aid writers, editors, and broadcasters help parents, teachers, older adults, and all consumers learn more about vision therapy. Following a description of vision therapy or vision training, information is provided on how and why vision therapy works. Additional sections address providers of…

  4. [Night shift work and prolactin as a breast cancer risk factor].

    PubMed

    Bukowska, Agnieszka; Pepłońska, Beata

    2013-01-01

    Prolactin - a hormone secreted in a circadian rhythm acts as a regulator of growth and development of the mammary glands. It has been observed that working at night increases breast cancer risk in women. Night shift work, probably carcinogenic to humans (Group 2A IARC), can disrupt a circadian rhythm, and thus potentially alter the rhythm of prolactin secretion. The aim of our work was to review epidemiological evidence on the association between prolactin and the risk of breast cancer and the influence of work at night on prolactin secretion. Search was done in the Medline database by keywords (shift work, work at night, risk of breast cancer and prolactin). 'The increased proliferation of breast cells activated by prolactin can promote the development of cancer. The results of the largest epidemiological prospective studies suggest the association between prolactin levels and the risk of breast cancer in women. So far, only seven studies have investigated the association between work at night and prolactin secretion. In three studies lower concentrations of prolactin have been observed in night shift workers. No relationship between the night shift work duration and prolactin level in women have been reported. Night shift work can modify the profile of prolactin secretion in night workers, probably decreasing the secretion of this hormone at night. It is therefore unlikely that prolactin plays an important role in the development of breast cancer in women working at night. This conclusion is based on the results of a few epidemiological studies.

  5. The World Water Vision: From Developing a Vision to Action

    NASA Astrophysics Data System (ADS)

    Gangopadhyay, S.; Cosgrove, W.; Rijsberman, F.; Strzepek, K.; Strzepek, K.

    2001-05-01

    The World Water Vision exercise was initiated by the World Water Commission under the auspices of the World Water Council. The goal of the World Water Vision project was to develop a widely shared vision on the actions required to achieve a common set of water-related goals and the necessary commitment to carry out these actions. The Vision should be participatory in nature, including input from both developed and developing regions, with a special focus on the needs of the poor, women, youth, children and the environment. Three overall objectives were to: (i)raise awareness of water issues among both the general population and decision-makers so as to foster the necessary political will and leadership to tackle the problems seriously and systematically; (ii) develop a vision of water management for 2025 that is shared by water sector specialists as well as international, national and regional decision-makers in government, the private sector and civil society; and (iii) provide input to a Framework for Action to be elaborated by the Global Water Partnership, with steps to go from vision to action, including recommendations to funding agencies for investment priorities. This exercise was characterized by the principles of: (i) a participatory approach with extensive consultation; (ii) Innovative thinking; (iii) central analysis to assure integration and co-ordination; and (iv) emphasis on communication with groups outside the water sector. The primary activities included, developing global water scenarios that fed into regional consultations and sectoral consultations as water for food, water for people - water supply and sanitation, and water and environment. These consultations formulated the regional and sectoral visions that were synthesized to form the World Water Vision. The findings from this exercise were reported and debated at the Second World Water Forum and the Ministerial Conference held in The Hague, The Netherlands during April 2000. This paper

  6. From geospatial observations of ocean currents to causal predictors of spatio-economic activity using computer vision and machine learning

    NASA Astrophysics Data System (ADS)

    Popescu, Florin; Ayache, Stephane; Escalera, Sergio; Baró Solé, Xavier; Capponi, Cecile; Panciatici, Patrick; Guyon, Isabelle

    2016-04-01

    The big data transformation currently revolutionizing science and industry forges novel possibilities in multi-modal analysis scarcely imaginable only a decade ago. One of the important economic and industrial problems that stand to benefit from the recent expansion of data availability and computational prowess is the prediction of electricity demand and renewable energy generation. Both are correlates of human activity: spatiotemporal energy consumption patterns in society are a factor of both demand (weather dependent) and supply, which determine cost - a relation expected to strengthen along with increasing renewable energy dependence. One of the main drivers of European weather patterns is the activity of the Atlantic Ocean and in particular its dominant Northern Hemisphere current: the Gulf Stream. We choose this particular current as a test case in part due to larger amount of relevant data and scientific literature available for refinement of analysis techniques. This data richness is due not only to its economic importance but also to its size being clearly visible in radar and infrared satellite imagery, which makes it easier to detect using Computer Vision (CV). The power of CV techniques makes basic analysis thus developed scalable to other smaller and less known, but still influential, currents, which are not just curves on a map, but complex, evolving, moving branching trees in 3D projected onto a 2D image. We investigate means of extracting, from several image modalities (including recently available Copernicus radar and earlier Infrared satellites), a parameterized representation of the state of the Gulf Stream and its environment that is useful as feature space representation in a machine learning context, in this case with the EC's H2020-sponsored 'See.4C' project, in the context of which data scientists may find novel predictors of spatiotemporal energy flow. Although automated extractors of Gulf Stream position exist, they differ in methodology

  7. In the darkness of the polar night, scallops keep on a steady rhythm

    PubMed Central

    Tran, Damien; Sow, Mohamedou; Camus, Lionel; Ciret, Pierre; Berge, Jorgen; Massabuau, Jean-Charles

    2016-01-01

    Although the prevailing paradigm has held that the polar night is a period of biological quiescence, recent studies have detected noticeable activity levels in marine organisms. In this study, we investigated the circadian rhythm of the scallop Chlamys islandica by continuously recording the animal’s behaviour over 3 years in the Arctic (Svalbard). Our results showed that a circadian rhythm persists throughout the polar night and lasts for at least 4 months. Based on observations across three polar nights, we showed that the robustness and synchronicity of the rhythm depends on the angle of the sun below the horizon. The weakest rhythm occurred at the onset of the polar night during the nautical twilight. Surprisingly, the circadian behaviour began to recover during the darkest part of the polar night. Because active rhythms optimize the fitness of an organism, our study brings out that the scallops C. islandica remain active even during the polar night. PMID:27577847

  8. In the darkness of the polar night, scallops keep on a steady rhythm

    NASA Astrophysics Data System (ADS)

    Tran, Damien; Sow, Mohamedou; Camus, Lionel; Ciret, Pierre; Berge, Jorgen; Massabuau, Jean-Charles

    2016-08-01

    Although the prevailing paradigm has held that the polar night is a period of biological quiescence, recent studies have detected noticeable activity levels in marine organisms. In this study, we investigated the circadian rhythm of the scallop Chlamys islandica by continuously recording the animal’s behaviour over 3 years in the Arctic (Svalbard). Our results showed that a circadian rhythm persists throughout the polar night and lasts for at least 4 months. Based on observations across three polar nights, we showed that the robustness and synchronicity of the rhythm depends on the angle of the sun below the horizon. The weakest rhythm occurred at the onset of the polar night during the nautical twilight. Surprisingly, the circadian behaviour began to recover during the darkest part of the polar night. Because active rhythms optimize the fitness of an organism, our study brings out that the scallops C. islandica remain active even during the polar night.

  9. Human gene therapy for RPE65 isomerase deficiency activates the retinoid cycle of vision but with slow rod kinetics.

    PubMed

    Cideciyan, Artur V; Aleman, Tomas S; Boye, Sanford L; Schwartz, Sharon B; Kaushal, Shalesh; Roman, Alejandro J; Pang, Ji-Jing; Sumaroka, Alexander; Windsor, Elizabeth A M; Wilson, James M; Flotte, Terence R; Fishman, Gerald A; Heon, Elise; Stone, Edwin M; Byrne, Barry J; Jacobson, Samuel G; Hauswirth, William W

    2008-09-30

    The RPE65 gene encodes the isomerase of the retinoid cycle, the enzymatic pathway that underlies mammalian vision. Mutations in RPE65 disrupt the retinoid cycle and cause a congenital human blindness known as Leber congenital amaurosis (LCA). We used adeno-associated virus-2-based RPE65 gene replacement therapy to treat three young adults with RPE65-LCA and measured their vision before and up to 90 days after the intervention. All three patients showed a statistically significant increase in visual sensitivity at 30 days after treatment localized to retinal areas that had received the vector. There were no changes in the effect between 30 and 90 days. Both cone- and rod-photoreceptor-based vision could be demonstrated in treated areas. For cones, there were increases of up to 1.7 log units (i.e., 50 fold); and for rods, there were gains of up to 4.8 log units (i.e., 63,000 fold). To assess what fraction of full vision potential was restored by gene therapy, we related the degree of light sensitivity to the level of remaining photoreceptors within the treatment area. We found that the intervention could overcome nearly all of the loss of light sensitivity resulting from the biochemical blockade. However, this reconstituted retinoid cycle was not completely normal. Resensitization kinetics of the newly treated rods were remarkably slow and required 8 h or more for the attainment of full sensitivity, compared with <1 h in normal eyes. Cone-sensitivity recovery time was rapid. These results demonstrate dramatic, albeit imperfect, recovery of rod- and cone-photoreceptor-based vision after RPE65 gene therapy.

  10. Flight test of monocular day/night HMD systems

    NASA Astrophysics Data System (ADS)

    Hudson, Craig; Longman, Peter J.; Makepeace, Nat R.

    2002-08-01

    The Crew Systems Group at QinetiQ Farnborough, formerly part of the Defence Evaluation and Research Agency (DERA), have recently conducted development and flight evaluations of two monocular display systems that provided dynamic symbology for the pilot. The systems were the Pilkington Optronics (now Thales) Guardian monocular Helmet Mounted Display (HMD) used for daytime operations and the QinetiQ Display Night Vision Goggles (DNVGs) used at night. Test flights of the two systems were performed in a modified Jaguar T2B combat aircraft, that was based at the QinetiQ Boscombe Down research facility. Good performance was obtained from each system with both producing clear, legible symbology. During day and night Air to Ground (A-G) sorties both the Guardian and the DNVGs were used for simulated attacks and reconnaissance tasks on a variety of operationally realistic targets. In addition the Guardian HMD was used with an ASRAAM in the day Air to Air (A-A) environment to provide high off-boresight capability. The results from the test program have validated a range of significant capability enhancements offered by either a HMD or a DNVG, and have provided a significant increase in the technical and operational understanding of fast-jet helmet display systems.

  11. The first World Atlas of the artificial night sky brightness

    NASA Astrophysics Data System (ADS)

    Cinzano, P.; Falchi, F.; Elvidge, C. D.

    2001-12-01

    We present the first World Atlas of the zenith artificial night sky brightness at sea level. Based on radiance-calibrated high-resolution DMSP satellite data and on accurate modelling of light propagation in the atmosphere, it provides a nearly global picture of how mankind is proceeding to envelop itself in a luminous fog. Comparing the Atlas with the United States Department of Energy (DOE) population density data base, we determined the fraction of population who are living under a sky of given brightness. About two-thirds of the World population and 99 per cent of the population in the United States (excluding Alaska and Hawaii) and European Union live in areas where the night sky is above the threshold set for polluted status. Assuming average eye functionality, about one-fifth of the World population, more than two-thirds of the United States population and more than one half of the European Union population have already lost naked eye visibility of the Milky Way. Finally, about one-tenth of the World population, more than 40 per cent of the United States population and one sixth of the European Union population no longer view the heavens with the eye adapted to night vision, because of the sky brightness.

  12. Night terrors: strategies for family coping.

    PubMed

    Gates, D; Morwessel, N

    1989-02-01

    This article discusses the occurrence of night terrors (parvor nocturnus) in children. The characteristics of a typical night terror incident are described, as are the common parental reactions to such frightening events. Nurses who work with children and families need to know about the etiology and clinical course of night terrors. They need to be able to differentiate night terrors from other sleep disturbances and determine possible ways to alleviate the occurrences. This article emphasizes assessment, anticipatory guidance, education, and counseling. A practical guide for parents is included to provide families with information on ways to cope with night terrors.

  13. Healthy Living, Healthy Vision

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  14. Pregnancy and Your Vision

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  15. Tactical Night Terrain Flight Navigation

    DTIC Science & Technology

    1979-09-01

    an reverse aide It necesarmy and identify by block unmber) Terrain flight Night flight Surface nav’igation 20,. AW4~ACT ( C ~venoUa sov ero " eom a maa...were used on each test flight. The helicopter used for the low-level flights were equipped initially with a commercial radar altimeter with a single...indicator, which was later changed to a military AN/APN-209 radar altimeter with dual indicators. The second helicopter was used for command and

  16. Binocular Vision

    PubMed Central

    Blake, Randolph; Wilson, Hugh

    2010-01-01

    This essay reviews major developments –empirical and theoretical –in the field of binocular vision during the last 25 years. We limit our survey primarily to work on human stereopsis, binocular rivalry and binocular contrast summation, with discussion where relevant of single-unit neurophysiology and human brain imaging. We identify several key controversies that have stimulated important work on these problems. In the case of stereopsis those controversies include position versus phase encoding of disparity, dependence of disparity limits on spatial scale, role of occlusion in binocular depth and surface perception, and motion in 3D. In the case of binocular rivalry, controversies include eye versus stimulus rivalry, role of “top-down” influences on rivalry dynamics, and the interaction of binocular rivalry and stereopsis. Concerning binocular contrast summation, the essay focuses on two representative models that highlight the evolving complexity in this field of study. PMID:20951722

  17. Robot Vision

    NASA Technical Reports Server (NTRS)

    Sutro, L. L.; Lerman, J. B.

    1973-01-01

    The operation of a system is described that is built both to model the vision of primate animals, including man, and serve as a pre-prototype of possible object recognition system. It was employed in a series of experiments to determine the practicability of matching left and right images of a scene to determine the range and form of objects. The experiments started with computer generated random-dot stereograms as inputs and progressed through random square stereograms to a real scene. The major problems were the elimination of spurious matches, between the left and right views, and the interpretation of ambiguous regions, on the left side of an object that can be viewed only by the left camera, and on the right side of an object that can be viewed only by the right camera.

  18. Artificial vision.

    PubMed

    Humayun, M S; de Juan, E

    1998-01-01

    Outer retinal degenerations such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD) lead to blindness because of photoreceptor degeneration. To test whether controlled electrical stimulation of the remaining retinal neurons could provide form vision, we electrically stimulated the inner retinal surface with micro-electrodes inserted through the sclera/eye wall of 14 of these patients (12 RP and 2 AMD). This procedure was performed in the operating room under local anaesthesia and all responses were recorded via a video camera mounted on the surgical microscope. Electrical stimulation of the inner retinal surface elicited visual perception of a spot of light (phosphene) in all subjects. This perception was retinotopically correct in 13 of 14 patients. In a resolution test in a subject with no light perception, the patient could resolve phosphenes at 1.75 degrees centre-to-centre distance (i.e. visual acuity compatible with mobility; Snellen visual acuity of 4/200).

  19. Vision Screening

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Visi Screen OSS-C, marketed by Vision Research Corporation, incorporates image processing technology originally developed by Marshall Space Flight Center. Its advantage in eye screening is speed. Because it requires no response from a subject, it can be used to detect eye problems in very young children. An electronic flash from a 35 millimeter camera sends light into a child's eyes, which is reflected back to the camera lens. The photorefractor then analyzes the retinal reflexes generated and produces an image of the child's eyes, which enables a trained observer to identify any defects. The device is used by pediatricians, day care centers and civic organizations that concentrate on children with special needs.

  20. Lateralized activation of Cluster N in the brains of migratory songbirds.

    PubMed

    Liedvogel, Miriam; Feenders, Gesa; Wada, Kazuhiro; Troje, Nikolaus F; Jarvis, Erich D; Mouritsen, Henrik

    2007-02-01

    Cluster N is a cluster of forebrain regions found in night-migratory songbirds that shows high activation of activity-dependent gene expression during night-time vision. We have suggested that Cluster N may function as a specialized night-vision area in night-migratory birds and that it may be involved in processing light-mediated magnetic compass information. Here, we investigated these ideas. We found a significant lateralized dominance of Cluster N activation in the right hemisphere of European robins (Erithacus rubecula). Activation predominantly originated from the contralateral (left) eye. Garden warblers (Sylvia borin) tested under different magnetic field conditions and under monochromatic red light did not show significant differences in Cluster N activation. In the fairly sedentary Sardinian warbler (Sylvia melanocephala), which belongs to the same phyolgenetic clade, Cluster N showed prominent activation levels, similar to that observed in garden warblers and European robins. Thus, it seems that Cluster N activation occurs at night in all species within predominantly migratory groups of birds, probably because such birds have the capability of switching between migratory and sedentary life styles. The activation studies suggest that although Cluster N is lateralized, as is the dependence on magnetic compass orientation, either Cluster N is not involved in magnetic processing or the magnetic modulations of the primary visual signal, forming the basis for the currently supported light-dependent magnetic compass mechanism, are relatively small such that activity-dependent gene expression changes are not sensitive enough to pick them up.

  1. Arabian sandflies (Diptera: Psychodidae) prefer the hottest nights?

    PubMed

    Roberts, D M

    1994-04-01

    A vehicle-mounted net was used to collect hourly samples of sandflies on 15 nights during June in northern Oman. Every half hour, the temperature, relative humidity, wind velocity and light intensity were measured (there was no cloud or rainfall during this period). The sandflies caught were mainly Phlebotomus alexandri and Sergentomyia clydei. Their circadian activity increased rapidly after sunset (18.50 hours). The high level of activity was fairly constant during 9h of darkness until dawn, when it decreased rapidly. A few flies were still active at 07.00 hours, 1.5h after sunrise. A multiple regression showed that the main factor affecting sandfly activity was light intensity. When this factor was removed, by considering only the 135 catches collected during the 9h of darkness, the second most important factor was low relative humidity, followed by low wind velocity. Temperature was not a significant factor in the analysis, because of its strong negative correlation with humidity. However, when the effect of humidity was removed from the regression, high temperature became significant, but less important than wind. The regressions showed that, for flight activity, the optimum humidity was around 10%; the probable maximum wind velocity was 3.5 m s-1 and 11 degrees C was the probable minimum temperature. Thus, when the 4 nights with highest catches (200-260 flies/night) were compared with the 4 nights with lowest catches (50-120 flies/night), the best nights had a low humidity (10-25%) and low wind speed (< 0.3 m s-1) in combination with highest temperatures (31-43 degrees C).

  2. 2010 National Observe the Moon Night!

    NASA Astrophysics Data System (ADS)

    Daou, Doris; Hsu, B. C.; Bleacher, L. V.; Day, B.; Jones, A.; Mitchell, B.; Shaner, A.; Shipp, S.

    2010-05-01

    We are creating a nation-wide, annual public outreach event called "National Observe the Moon Night” (NOMN) that provides opportunities for involving new partners in engaging the public in lunar science and exploration. The 2010 NOMN events will occur at our partner institutions - Ames Research Center (ARC; Moffett Field, CA), Goddard Space Flight Center (GFSC; Greenbelt, MD), Lunar and Planetary Institute (LPI; Houston, TX), and Marshall Space Flight Center (MSFC; Huntsville, AL). The goal of National Observe the Moon Night is to engage the lunar science and education community, our partner networks, amateur astronomers, space enthusiasts, and the general public in annual lunar observation campaigns that share the excitement of lunar science and exploration. National Observe the Moon Night events will use NASA's "Tweet-ups" model and partners' dissemination networks to promote and recruit participation in the events. All information about NOMN will be supplied on a central website, accessible to the public (http://mymoon.lpi.usra.edu/nationalobservethemoonnight). Members of the public are encouraged to host their own NOMN events, and there will be a place for local astronomy clubs, schools, or other groups to post information about NOMN events they are organizing. To assist with their efforts, the website will contain downloadable documents of templates of advertising fliers, Moon maps, and activities that will be distributed at the national events, such as Moon calendar journals. After the events, participants will be able to continue using the website to follow links for more information about sites indicated on their Moon maps.

  3. Stennis hosts NASA Night in Oxford

    NASA Technical Reports Server (NTRS)

    2010-01-01

    A young visitor to the Powerhouse Community Arts and Cultural Center in Oxford, Miss., enjoys a balloon rocket transportation activity during a NASA Night in the Neighborhood on March 29. NASA's John C. Stennis Space Center near Bay St. Louis visited the center with a variety of space-related displays and educational activities. Events targeted for children included moon phasers and build-your-own rocket transportation exercises, as well as an astronaut ice cream tasting station. Visitors also were able to take photos in the astronaut suit display. Displays focused on the 40th anniversaries of the Apollo 11 and Apollo 13 lunar missions, the International Space Station, and various aspects of Stennis work. The event was sponsored by the NASA Office of External Affairs and Education at Stennis.

  4. NV-CMOS HD camera for day/night imaging

    NASA Astrophysics Data System (ADS)

    Vogelsong, T.; Tower, J.; Sudol, Thomas; Senko, T.; Chodelka, D.

    2014-06-01

    SRI International (SRI) has developed a new multi-purpose day/night video camera with low-light imaging performance comparable to an image intensifier, while offering the size, weight, ruggedness, and cost advantages enabled by the use of SRI's NV-CMOS HD digital image sensor chip. The digital video output is ideal for image enhancement, sharing with others through networking, video capture for data analysis, or fusion with thermal cameras. The camera provides Camera Link output with HD/WUXGA resolution of 1920 x 1200 pixels operating at 60 Hz. Windowing to smaller sizes enables operation at higher frame rates. High sensitivity is achieved through use of backside illumination, providing high Quantum Efficiency (QE) across the visible and near infrared (NIR) bands (peak QE <90%), as well as projected low noise (<2h+) readout. Power consumption is minimized in the camera, which operates from a single 5V supply. The NVCMOS HD camera provides a substantial reduction in size, weight, and power (SWaP) , ideal for SWaP-constrained day/night imaging platforms such as UAVs, ground vehicles, fixed mount surveillance, and may be reconfigured for mobile soldier operations such as night vision goggles and weapon sights. In addition the camera with the NV-CMOS HD imager is suitable for high performance digital cinematography/broadcast systems, biofluorescence/microscopy imaging, day/night security and surveillance, and other high-end applications which require HD video imaging with high sensitivity and wide dynamic range. The camera comes with an array of lens mounts including C-mount and F-mount. The latest test data from the NV-CMOS HD camera will be presented.

  5. Ares Valles: Night and Day

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 15 June 2004 This pair of images shows part of the Ares Valles region.

    Day/Night Infrared Pairs

    The image pairs presented focus on a single surface feature as seen in both the daytime and nighttime by the infrared THEMIS camera. The nighttime image (right) has been rotated 180 degrees to place north at the top.

    Infrared image interpretation

    Daytime: Infrared images taken during the daytime exhibit both the morphological and thermophysical properties of the surface of Mars. Morphologic details are visible due to the effect of sun-facing slopes receiving more energy than antisun-facing slopes. This creates a warm (bright) slope and cool (dark) slope appearance that mimics the light and shadows of a visible wavelength image. Thermophysical properties are seen in that dust heats up more quickly than rocks. Thus dusty areas are bright and rocky areas are dark.

    Nighttime: Infrared images taken during the nighttime exhibit only the thermophysical properties of the surface of Mars. The effect of sun-facing versus non-sun-facing energy dissipates quickly at night. Thermophysical effects dominate as different surfaces cool at different rates through the nighttime hours. Rocks cool slowly, and are therefore relatively bright at night (remember that rocks are dark during the day). Dust and other fine grained materials cool very quickly and are dark in nighttime infrared images.

    Image information: IR instrument. Latitude 3.6, Longitude 339.9 East (20.1 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released

  6. Channel by Day and Night

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 17 June 2004 This pair of images shows part of a small channel.

    Day/Night Infrared Pairs

    The image pairs presented focus on a single surface feature as seen in both the daytime and nighttime by the infrared THEMIS camera. The nighttime image (right) has been rotated 180 degrees to place north at the top.

    Infrared image interpretation

    Daytime: Infrared images taken during the daytime exhibit both the morphological and thermophysical properties of the surface of Mars. Morphologic details are visible due to the effect of sun-facing slopes receiving more energy than antisun-facing slopes. This creates a warm (bright) slope and cool (dark) slope appearance that mimics the light and shadows of a visible wavelength image. Thermophysical properties are seen in that dust heats up more quickly than rocks. Thus dusty areas are bright and rocky areas are dark.

    Nighttime: Infrared images taken during the nighttime exhibit only the thermophysical properties of the surface of Mars. The effect of sun-facing versus non-sun-facing energy dissipates quickly at night. Thermophysical effects dominate as different surfaces cool at different rates through the nighttime hours. Rocks cool slowly, and are therefore relatively bright at night (remember that rocks are dark during the day). Dust and other fine grained materials cool very quickly and are dark in nighttime infrared images.

    Image information: IR instrument. Latitude 19.8, Longitude 141.5 East (218.5 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through

  7. Lomonosov Crater, Day and Night

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    Released 16 June 2004 This pair of images shows part of Lomonosov Crater.

    Day/Night Infrared Pairs

    The image pairs presented focus on a single surface feature as seen in both the daytime and nighttime by the infrared THEMIS camera. The nighttime image (right) has been rotated 180 degrees to place north at the top.

    Infrared image interpretation

    Daytime: Infrared images taken during the daytime exhibit both the morphological and thermophysical properties of the surface of Mars. Morphologic details are visible due to the effect of sun-facing slopes receiving more energy than antisun-facing slopes. This creates a warm (bright) slope and cool (dark) slope appearance that mimics the light and shadows of a visible wavelength image. Thermophysical properties are seen in that dust heats up more quickly than rocks. Thus dusty areas are bright and rocky areas are dark.

    Nighttime: Infrared images taken during the nighttime exhibit only the thermophysical properties of the surface of Mars. The effect of sun-facing versus non-sun-facing energy dissipates quickly at night. Thermophysical effects dominate as different surfaces cool at different rates through the nighttime hours. Rocks cool slowly, and are therefore relatively bright at night (remember that rocks are dark during the day). Dust and other fine grained materials cool very quickly and are dark in nighttime infrared images.

    Image information: IR instrument. Latitude 64.9, Longitude 350.7 East (9.3 West). 100 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through

  8. Melas Chasma, Day and Night.

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image is a mosaic of day and night infrared images of Melas Chasma taken by the camera system on NASA's Mars Odyssey spacecraft. The daytime temperature images are shown in black and white, superimposed on the martian topography. A single nighttime temperature image is superimposed in color. The daytime temperatures range from approximately -35 degrees Celsius (-31 degrees Fahrenheit) in black to -5 degrees Celsius (23 degrees Fahrenheit) in white. Overlapping landslides and individual layers in the walls of Melas Chasma can be seen in this image. The landslides flowed over 100 kilometers (62 miles) across the floor of Melas Chasma, producing deposits with ridges and grooves of alternating warm and cold materials that can still be seen. The temperature differences in the daytime images are due primarily to lighting effects, where sunlit slopes are warm (bright) and shadowed slopes are cool (dark). The nighttime temperature differences are due to differences in the abundance of rocky materials that retain their heat at night and stay relatively warm (red). Fine grained dust and sand (blue) cools off more rapidly at night. These images were acquired using the thermal infrared imaging system infrared Band 9, centered at 12.6 micrometers.

    Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the 2001 Mars Odyssey mission for NASA's Office of Space Science in Washington, D.C. Investigators at Arizona State University in Tempe, the University of Arizona in Tucson and NASA's Johnson Space Center, Houston, operate the science instruments. Additional science partners are located at the Russian Aviation and Space Agency and at Los Alamos National Laboratories, New Mexico. Lockheed Martin Astronautics, Denver, is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL. Aviation and Space Agency and at Los Alamos National

  9. Hereditary factors in sleepwalking and night terrors.

    PubMed

    Kales, A; Soldatos, C R; Bixler, E O; Ladda, R L; Charney, D S; Weber, G; Schweitzer, P K

    1980-08-01

    The families of 25 probands with sleepwalking and 27 probands with night terrors were studied. Eighty per cent of the sleepwalking pedigrees and 96 per cent of the night terror pedigrees included one or more individuals, other than the proband, who were affected by sleepwalking, night terrors, or both. Our data appear to fit a 'two threshold' multifactorial mode of inheritance. This finding supports the hypothesis that sleepwalking and night terrors share a common genetic predisposition, with sleepwalking being a more prevalent and less severe manifestation of the same substrate that underlies night terrors. Heritable factors predispose an individual to develop sleepwalking and/or night terrors, but expression of the trait may be influenced by environmental factors.

  10. Simplified Night Sky Display System

    NASA Technical Reports Server (NTRS)

    Castellano, Timothy P.

    2010-01-01

    A document describes a simple night sky display system that is portable, lightweight, and includes, at most, four components in its simplest configuration. The total volume of this system is no more than 10(sup 6) cm(sup 3) in a disassembled state, and weighs no more than 20 kilograms. The four basic components are a computer, a projector, a spherical light-reflecting first surface and mount, and a spherical second surface for display. The computer has temporary or permanent memory that contains at least one signal representing one or more images of a portion of the sky when viewed from an arbitrary position, and at a selected time. The first surface reflector is spherical and receives and reflects the image from the projector onto the second surface, which is shaped like a hemisphere. This system may be used to simulate selected portions of the night sky, preserving the appearance and kinesthetic sense of the celestial sphere surrounding the Earth or any other point in space. These points will then show motions of planets, stars, galaxies, nebulae, and comets that are visible from that position. The images may be motionless, or move with the passage of time. The array of images presented, and vantage points in space, are limited only by the computer software that is available, or can be developed. An optional approach is to have the screen (second surface) self-inflate by means of gas within the enclosed volume, and then self-regulate that gas in order to support itself without any other mechanical support.

  11. [Night-to-night variability of the obstructive sleep apnoea-hypopnoea syndrome].

    PubMed

    Mjid, M; Ouahchi, Y; Toujani, S; Snen, H; Ben Salah, N; Ben Hmida, A; Louzir, B; Mhiri, N; Cherif, J; Beji, M

    2016-11-01

    The apnoea-hypopnoea index (AHI) is the primary measurement used to characterize the obstructive sleep apnoea-hypopnoea syndrome (OSAHS). Despite its popularity, there are limiting factors to its application such as night-to-night variability.

  12. A truncated form of rod photoreceptor PDE6 β-subunit causes autosomal dominant congenital stationary night blindness by interfering with the inhibitory activity of the γ-subunit.

    PubMed

    Manes, Gaël; Cheguru, Pallavi; Majumder, Anurima; Bocquet, Béatrice; Sénéchal, Audrey; Artemyev, Nikolai O; Hamel, Christian P; Brabet, Philippe

    2014-01-01

    Autosomal dominant congenital stationary night blindness (adCSNB) is caused by mutations in three genes of the rod phototransduction cascade, rhodopsin (RHO), transducin α-subunit (GNAT1), and cGMP phosphodiesterase type 6 β-subunit (PDE6B). In most cases, the constitutive activation of the phototransduction cascade is a prerequisite to cause adCSNB. The unique adCSNB-associated PDE6B mutation found in the Rambusch pedigree, the substitution p.His258Asn, leads to rod photoreceptors desensitization. Here, we report a three-generation French family with adCSNB harboring a novel PDE6B mutation, the duplication, c.928-9_940dup resulting in a tyrosine to cysteine substitution at codon 314, a frameshift, and a premature termination (p.Tyr314Cysfs*50). To understand the mechanism of the PDE6β1-314fs*50 mutant, we examined the properties of its PDE6-specific portion, PDE6β1-313. We found that PDE6β1-313 maintains the ability to bind noncatalytic cGMP and the inhibitory γ-subunit (Pγ), and interferes with the inhibition of normal PDE6αβ catalytic subunits by Pγ. Moreover, both truncated forms of the PDE6β protein, PDE6β1-313 and PDE6β1-314fs*50 expressed in rods of transgenic X. laevis are targeted to the phototransduction compartment. We hypothesize that in affected family members the p.Tyr314Cysfs*50 change results in the production of the truncated protein, which binds Pγ and causes constitutive activation of the phototransduction thus leading to the absence of rod adaptation.

  13. Development of Air Force Aerial Spray Night Operations: High Altitude Swath Characterizations.

    PubMed

    Haagsma, Karl A; Breidenbaugh, Mark S; Linthicum, Kenneth J; Aldridge, Robert L; Britch, Seth C

    2015-01-01

    Multiple trials were conducted from 2006 to 2014 in an attempt to validate aerial spray efficacy at altitudes conducive to night spray operations using night vision goggles (NVGs). Higher altitude application of pesticide (more than 400 ft (121.9 m) above ground level (AGL)) suggested that effective vector control might be possible under ideal meteorological conditions. A series of lower altitude daytime applications (300 ft (91.4 m) AGL) demonstrated effective and repeatable mortality of target sentinel insects more than 5,000 ft (1,524 m) downwind, and control of natural vector populations. From these results we believe further pursuit of aerial night applications of pesticide using NVGs at 300 ft (91.4 m) AGL by this group is warranted.

  14. NASA Vision

    NASA Technical Reports Server (NTRS)

    Fenton, Mary (Editor); Wood, Jennifer (Editor)

    2003-01-01

    This newsletter contains several articles, primarily on International Space Station (ISS) crewmembers and their activities, as well as the activities of NASA administrators. Other subjects covered in the articles include the investigation of the Space Shuttle Columbia accident, activities at NASA centers, Mars exploration, a collision avoidance test on a unmanned aerial vehicle (UAV). The ISS articles cover landing in a Soyuz capsule, photography from the ISS, and the Expedition Seven crew.

  15. Seeing Stars: A GLOBE at Night Campaign Update

    NASA Astrophysics Data System (ADS)

    Walker, Constance E.; Pompea, S. M.; Sparks, R. T.; Newhouse, M.

    2012-01-01

    The emphasis in the international citizen-science, star-hunting campaign, GLOBE at Night, is in bringing awareness to the public on issues of light pollution. Light pollution threatens not only observatory sites and our "right to starlight", but can affect energy consumption, wildlife and health. GLOBE at Night has successfully reached a few 100,000 citizen-scientists. What has done in the last year to contribute to its success? • To promote the campaign via popular social media, GLOBE at Night created Facebook and Twitter pages. • Videos have been created for 4 out of 8 Dark Skies Rangers activities. • Sky brightness measurements can be submitted in real time with smart phones or tablets using the new Web application at www.globeatnight.org/webapp/. The location, date and time register automatically. • As a proto-type, an adopt-a-street program had people in Tucson take measurements every mile for the length of the street. Grid measurements canvassed the town, allowing for comparisons of light levels over time. • The increase to 2 campaigns in 2011 re-enforces these studies. In 2012, the campaign will be offered 4 times for 10 days a month: January 14-23, February 12-21, March 13-22 and April 11-20. • A new Web application (www.globeatnight.org/mapapp/) allows for mapping GLOBE at Night data points within a specified distance around a city or area of choice. The resulting maps are bookmarkable and shareable. • NOAO and Arizona Game and Fish Department started a project with GLOBE at Night data and bat telemetry to examine a dark skies corridor in Tucson where endangered bats fly. While providing these updates to the GLOBE at Night program, the presentation will highlight the education and outreach value of the program's resources and outcomes, lessons learned, successes and pitfalls in communicating awareness with the public and attracting young people to study science.

  16. 77 FR 62147 - Night Definition; Technical Amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-12

    ... [Docket No. FAA-2012-1043; Amdt. Nos. 1-1] Night Definition; Technical Amendment AGENCY: Federal Aviation..., the United States, and Canada. In 14 CFR 1.1 the definition of night refers to twilight times as... Administration amends chapter I of title 14, Code of Federal Regulations as follows: PART 1--DEFINITIONS...

  17. The Night Sky on Mars

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Taking advantage of extra solar energy collected during the day, NASA's Mars Exploration Rover Spirit settled in for an evening of stargazing, photographing the two moons of Mars as they crossed the night sky. This time-lapse composite, acquired the evening of Spirit's martian sol 590 (Aug. 30, 2005) from a perch atop 'Husband Hill' in Gusev Crater, shows Phobos, the brighter moon, on the left, and Deimos, the dimmer moon, on the right. In this sequence of images obtained every 170 seconds, both moons move from top to bottom. The bright star Aldebaran forms a trail on the right, along with some other stars in the constellation Taurus. Most of the other streaks in the image mark the collision of cosmic rays with pixels in the camera.

    Scientists will use images of the two moons to better map their orbital positions, learn more about their composition, and monitor the presence of nighttime clouds or haze. Spirit took the six images that make up this composite using Spirit's panoramic camera with the camera's broadband filter, which was designed specifically for acquiring images under low-light conditions.

  18. Naked-eye astronomy: optics of the starry night skies

    NASA Astrophysics Data System (ADS)

    Bará, Salva

    2014-07-01

    The world at night offers a wealth of stimuli and opportunities as a resource for Optics education, at all age levels and from any (formal, non formal or informal) perspective. The starry sky and the urban nightscape provide a unique combination of pointlike sources with extremely different emission spectra and brightness levels on a generally darker, locally homogeneous background. This fact, combined with the particular characteristics of the human visual system under mesopic and scotopic conditions, provides a perfect setting for experiencing first-hand different optical phenomena of increasing levels of complexity: from the eye's point spread function to the luminance contrast threshold for source detection, from basic diffraction patterns to the intricate irradiance fluctuations due to atmospheric turbulence. Looking at the nightscape is also a perfect occasion to raise awareness on the increasing levels of light pollution associated to the misuse of public and private artificial light at night, to promote a sustainable use of lighting, and to take part in worldwide citizen science campaigns. Last but not least, night sky observing activities can be planned and developed following a very flexible schedule, allowing individual students to carry them out from home and sharing the results in the classroom as well as organizing social events and night star parties with the active engagement of families and groups of the local community. This contribution describes these possibilities and introduces some of the free resources available to put them in practice.

  19. Night-Vision Goggle Visual Performance During 12 Hours at 10,000 ft Altitude at Night Conditions

    DTIC Science & Technology

    2008-03-01

    lats and ta identify the va ri ab les that are invalved in the develapment .of NIHL . Methods. A tatal .of 232 healthy Calambian Air Farce pi lats...31.76 yrs., S.D.= 5.68, p= 0.01). There was a strang correlatian between NIHL and attendance ta discatheques (OR= 3.30, CI= 1.21-9.05). Knawledge .of...occupationa l hearing lass pragrams reduced the risk of hearing lass in 11% .of the pilats. The mast Important symptams .of NIHL identified by this

  20. Is part-night lighting an effective measure to limit the impacts of artificial lighting on bats?

    PubMed

    Azam, Clémentine; Kerbiriou, Christian; Vernet, Arthur; Julien, Jean-François; Bas, Yves; Plichard, Laura; Maratrat, Julie; Le Viol, Isabelle

    2015-12-01

    As light pollution is currently considered to be a major threat to biodiversity, different lighting management options are being explored to mitigate the impact of artificial lighting on wildlife. Although part-night lighting schemes have been adopted by many local authorities across Europe to reduce the carbon footprint and save energy, their effects on biodiversity are unknown. Through a paired, in situ experiment, we compared the activity levels of 8 bat species under unlit, part-night, and full-night lighting treatments in a rural area located 60 km south of Paris, France. We selected 36 study locations composed of 1 lit site and a paired unlit control site; 24 of these sites were located in areas subject to part-night lighting schemes, and 12 sites were in areas under standard, full-night lighting. There was significantly more activity on part-night lighting sites compared to full-night lighting sites for the late-emerging, light-sensitive Plecotus spp., and a similar pattern was observable for Myotis spp., although not significant. In contrast, part-night lighting did not influence the activity of early emerging bat species around streetlights, except for Pipistrellus pipistrellus for which there was significantly less activity on part-night lighting sites than on full-night lighting sites. Overall, no significant difference in activity between part- and full-night lighting sites were observed in 5 of the 8 species studied, suggesting that current part-night lighting schemes fail to encompass the range of activity of most bat species. We recommend that such schemes start earlier at night to effectively mitigate the adverse effects of artificial lighting on light-sensitive species, particularly along ecological corridors that are especially important to the persistence of biodiversity in urban landscapes.

  1. The Medawar Lecture 2001 Knowledge for vision: vision for knowledge

    PubMed Central

    Gregory, Richard L

    2005-01-01

    An evolutionary development of perception is suggested—from passive reception to active perception to explicit conception—earlier stages being largely retained and incorporated in later species. A key is innate and then individually learned knowledge, giving meaning to sensory signals. Inappropriate or misapplied knowledge produces rich cognitive phenomena of illusions, revealing normally hidden processes of vision, tentatively classified here in a ‘peeriodic table’. Phenomena of physiology are distinguished from phenomena of general rules and specific object knowledge. It is concluded that vision uses implicit knowledge, and provides knowledge for intelligent behaviour and for explicit conceptual understanding including science. PMID:16147519

  2. Identifying the computational requirements of an integrated top-down-bottom-up model for overt visual attention within an active vision system.

    PubMed

    McBride, Sebastian; Huelse, Martin; Lee, Mark

    2013-01-01

    Computational visual attention systems have been constructed in order for robots and other devices to detect and locate regions of interest in their visual world. Such systems often attempt to take account of what is known of the human visual system and employ concepts, such as 'active vision', to gain various perceived advantages. However, despite the potential for gaining insights from such experiments, the computational requirements for visual attention processing are often not clearly presented from a biological perspective. This was the primary objective of this study, attained through two specific phases of investigation: 1) conceptual modeling of a top-down-bottom-up framework through critical analysis of the psychophysical and neurophysiological literature, 2) implementation and validation of the model into robotic hardware (as a representative of an active vision system). Seven computational requirements were identified: 1) transformation of retinotopic to egocentric mappings, 2) spatial memory for the purposes of medium-term inhibition of return, 3) synchronization of 'where' and 'what' information from the two visual streams, 4) convergence of top-down and bottom-up information to a centralized point of information processing, 5) a threshold function to elicit saccade action, 6) a function to represent task relevance as a ratio of excitation and inhibition, and 7) derivation of excitation and inhibition values from object-associated feature classes. The model provides further insight into the nature of data representation and transfer between brain regions associated with the vertebrate 'active' visual attention system. In particular, the model lends strong support to the functional role of the lateral intraparietal region of the brain as a primary area of information consolidation that directs putative action through the use of a 'priority map'.

  3. Color vision test

    MedlinePlus

    ... from birth) color vision problems: Achromatopsia -- complete color blindness , seeing only shades of gray Deuteranopia -- difficulty telling ... test - color; Ishihara color vision test Images Color blindness tests References Adams AJ, Verdon WA, Spivey BE. ...

  4. Chemicals Industry Vision

    SciTech Connect

    none,

    1996-12-01

    Chemical industry leaders articulated a long-term vision for the industry, its markets, and its technology in the groundbreaking 1996 document Technology Vision 2020 - The U.S. Chemical Industry. (PDF 310 KB).

  5. NASA Vision

    NASA Technical Reports Server (NTRS)

    Prior, Edwin J.

    2003-01-01

    The political, economic, and enivronmental conditions of the twenty-first century demand new goals for NASA. These goals include the imaging of habitable extrasolar planets, expanded commercialization of low earth orbit, clean and rapid air transportation, environment protection, and distance learning. The presentation recommends strategies for pursuing these goals, and summarizes activities at NASA Langley Research Center (LaRC).

  6. A Robot Vision System.

    DTIC Science & Technology

    1985-12-01

    ix e ...... . . . . . . .. . - . 1 I. Introduction This project includes the design and implementation of a vision - based goal achievement system. The... vision system design base . Final Conclusions Stereo vision is useless beyond about 15 feet for the camera separation of .75 feet, a picture...model. Such monocular vision and modelling, duplicated for two cameras, would give a second source of model data for resolving ambiguities, and

  7. Bedtime problems and night wakings in children.

    PubMed

    Moore, Melisa; Meltzer, Lisa J; Mindell, Jodi A

    2008-09-01

    Bedtime problems and night wakings in children are extremely common, and the treatment literature demonstrates strong empirical support for behavioral interventions. Empirically validated interventions for bedtime problems and night wakings include extinction, graduated extinction, positive routines, and parental education. Most children respond to behavioral interventions, resulting not only in better sleep for the child, but also better sleep and improved daytime functioning for the entire family. This article reviews the presentation of bedtime problems and night wakings, empirically validated interventions, and challenges to treatment in both typically developing and special populations of children.

  8. Robot Vision Library

    NASA Technical Reports Server (NTRS)

    Howard, Andrew B.; Ansar, Adnan I.; Litwin, Todd E.; Goldberg, Steven B.

    2009-01-01

    The JPL Robot Vision Library (JPLV) provides real-time robot vision algorithms for developers who are not vision specialists. The package includes algorithms for stereo ranging, visual odometry and unsurveyed camera calibration, and has unique support for very wideangle lenses

  9. Computer vision in nuclear medicine

    NASA Astrophysics Data System (ADS)

    Sommer, Gerald

    1990-11-01

    Computervision is used to overcome the mismatch between user models and implementation models of software systems for image analysis in nuclear medicine. Computer vision in nuclear medicine results in an active support of the user by the system. This is reached by modeling of imaging equipment and schedules scenes of interest and the process of visual image interpretation. Computer vision is demonstrated especially in the low level and medium level range. Special highlights are given for the estimation of image quality an uniform approach to enhancement and restoration of images and analysis of shape and dynamics of patterns. 1.

  10. Behavioral phenotypic properties of a natural occurring rat model of congenital stationary night blindness with Cacna1f mutation.

    PubMed

    An, Jing; Wang, Li; Guo, Qun; Li, Li; Xia, Feng; Zhang, Zuoming

    2012-09-01

    Cacna1f gene mutation could lead to incomplete congenital stationary night blindness (iCSNB) disease. The CSNB-like phenotype rat is a spontaneous rat model caused by Cacna1f gene mutation. The present study explored the phenotypic properties of behavior performance in CSNB rats further. The vision-related behaviors of CSNB rats were assessed with a Morris water maze (MWM), passive avoidance tests, and open-field test. Motor ability was evaluated with a rotarod test and a wire hang test, and mechanical pain and thermalgia were used to evaluate sensory system function. Electroretinograms (ERGs) were recorded to evaluate the function of the retina. The vision-related results showed that longer latencies of escape and reduced probe trial in MWM for CSNB rats. There were more errors in avoidance test; CSNB rats were more active in the open field and presented a different pattern of exploration. The locomotor-related behaviors showed shorter falling latencies in the rotarod test and shorter gripping time in CSNB rats. And mechanical thresholds of pain increased in CSNB rats. The ERGs indicated that both the amplitude and latency of rod and cone systems were impaired in the CSNB rats. In summary, Cacna1f gene mutation changed the performance of various behaviors in the CSNB rat aside from vision-related phenotype. Cacna1f gene might play a role in a wide range of responses in the organism. These results confirm the importance of a comprehensive profile for understanding the behavior phenotype of Cacna1f gene mutation in CSNB rat.

  11. Antenna Technology and other Radio Frequency (RF) Communications Activities at the Glenn Research Center in Support of NASA's Exploration Vision

    NASA Technical Reports Server (NTRS)

    Miranda, Felix A.

    2007-01-01

    NASA s Vision for Space Exploration outlines a very ambitious program for the next several decades of the Space Agency endeavors. Ahead is the completion of the International Space Station (ISS); safely flight the shuttle (STS) until 2010; develop and fly the Crew Exploration Vehicle (Orion) by no later than 2014; return to the moon by no later than 2020; extend human presence across the solar system and beyond; implement a sustainable and affordable human and robotic program; develop supporting innovative technologies, knowledge and infrastructure; and promote international and commercial participation in exploration. To achieve these goals, a series of enabling technologies must be developed or matured in a timely manner. Some of these technologies are: spacecraft RF technology (e.g., high power sources and large antennas which using surface receive arrays can get up to 1 Gbps from Mars), uplink arraying (reduce reliance on large ground-based antennas and high operation costs; single point of failure; enable greater data-rates or greater effective distance; scalable, evolvable, flexible scheduling), software define radio (i.e., reconfigurable, flexible interoperability allows for in flight updates open architecture; reduces mass, power, volume), and optical communications (high capacity communications with low mass/power required; significantly increases data rates for deep space). This presentation will discuss some of the work being performed at the NASA Glenn Research Center, Cleveland, Ohio, in antenna technology as well as other on-going RF communications efforts.

  12. Genetics Home Reference: autosomal dominant congenital stationary night blindness

    MedlinePlus

    ... stationary night blindness autosomal dominant congenital stationary night blindness Enable Javascript to view the expand/collapse boxes. ... Close All Description Autosomal dominant congenital stationary night blindness is a disorder of the retina , which is ...

  13. MSFC Catches Geminids In The Night Sky

    NASA Video Gallery

    This video shows meteors captured by a wide-field camera at the NASA Marshall Space Flight Center on the night of December 12. There are 141 events; at least 77 of these are Geminids, based on thei...

  14. Fred Haise Honored at Aerospace Appreciation Night

    NASA Video Gallery

    Retired NASA astronaut and test pilot Fred Haise was honored recently by the Lancaster, Calif., Jethawks baseball team at its Aerospace Appreciation Night. Best known as one of the Apollo 13 crew, ...

  15. Computational approaches to vision

    NASA Technical Reports Server (NTRS)

    Barrow, H. G.; Tenenbaum, J. M.

    1986-01-01

    Vision is examined in terms of a computational process, and the competence, structure, and control of computer vision systems are analyzed. Theoretical and experimental data on the formation of a computer vision system are discussed. Consideration is given to early vision, the recovery of intrinsic surface characteristics, higher levels of interpretation, and system integration and control. A computational visual processing model is proposed and its architecture and operation are described. Examples of state-of-the-art vision systems, which include some of the levels of representation and processing mechanisms, are presented.

  16. Microwave vision for robots

    NASA Technical Reports Server (NTRS)

    Lewandowski, Leon; Struckman, Keith

    1994-01-01

    Microwave Vision (MV), a concept originally developed in 1985, could play a significant role in the solution to robotic vision problems. Originally our Microwave Vision concept was based on a pattern matching approach employing computer based stored replica correlation processing. Artificial Neural Network (ANN) processor technology offers an attractive alternative to the correlation processing approach, namely the ability to learn and to adapt to changing environments. This paper describes the Microwave Vision concept, some initial ANN-MV experiments, and the design of an ANN-MV system that has led to a second patent disclosure in the robotic vision field.

  17. A child's vision.

    PubMed

    Nye, Christina

    2014-06-01

    Implementing standard vision screening techniques in the primary care practice is the most effective means to detect children with potential vision problems at an age when the vision loss may be treatable. A critical period of vision development occurs in the first few weeks of life; thus, it is imperative that serious problems are detected at this time. Although it is not possible to quantitate an infant's vision, evaluating ocular health appropriately can mean the difference between sight and blindness and, in the case of retinoblastoma, life or death.

  18. Vision and multiple sclerosis.

    PubMed

    Hickman, Simon J; Raoof, Naz; McLean, Rebecca J; Gottlob, Irene

    2014-01-01

    Multiple sclerosis can affect vision in many ways, including optic neuritis, chronic optic neuropathy, retrochiasmal visual field defects, higher order cortical processing, double vision, nystagmus and also by related ocular conditions such as uveitis. There are also side effects from recently introduced multiple sclerosis treatments that can affect vision. This review will discuss all these aspects and how they come together to cause visual symptoms. It will then focus on practical aspects of how to recognise when there is a vision problem in a multiple sclerosis patient and on what treatments are available to improve vision.

  19. Nature's Late-Night Light Shows

    NASA Astrophysics Data System (ADS)

    Peterson, Carolyn Collins

    2002-09-01

    In addition to stars and planets, there are other interesting lights to be seen in the night sky. The northern and southern lights, called the aurora borealis and aurora australis, are created by charged particles from the Sun reacting in Earth's magnetic field. Night-shining clouds or noctilucent clouds appear at evening twilight as a result of water vapor in the polar mesosphere. Zodiacal light can be seen stretching up from the horizon after sunset or before sunrise.

  20. Colour vision deficiency.

    PubMed

    Simunovic, M P

    2010-05-01

    Colour vision deficiency is one of the commonest disorders of vision and can be divided into congenital and acquired forms. Congenital colour vision deficiency affects as many as 8% of males and 0.5% of females--the difference in prevalence reflects the fact that the commonest forms of congenital colour vision deficiency are inherited in an X-linked recessive manner. Until relatively recently, our understanding of the pathophysiological basis of colour vision deficiency largely rested on behavioural data; however, modern molecular genetic techniques have helped to elucidate its mechanisms. The current management of congenital colour vision deficiency lies chiefly in appropriate counselling (including career counselling). Although visual aids may be of benefit to those with colour vision deficiency when performing certain tasks, the evidence suggests that they do not enable wearers to obtain normal colour discrimination. In the future, gene therapy remains a possibility, with animal models demonstrating amelioration following treatment.

  1. Acquired color vision deficiency.

    PubMed

    Simunovic, Matthew P

    2016-01-01

    Acquired color vision deficiency occurs as the result of ocular, neurologic, or systemic disease. A wide array of conditions may affect color vision, ranging from diseases of the ocular media through to pathology of the visual cortex. Traditionally, acquired color vision deficiency is considered a separate entity from congenital color vision deficiency, although emerging clinical and molecular genetic data would suggest a degree of overlap. We review the pathophysiology of acquired color vision deficiency, the data on its prevalence, theories for the preponderance of acquired S-mechanism (or tritan) deficiency, and discuss tests of color vision. We also briefly review the types of color vision deficiencies encountered in ocular disease, with an emphasis placed on larger or more detailed clinical investigations.

  2. Coherent laser vision system

    SciTech Connect

    Sebastion, R.L.

    1995-10-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system.

  3. Effect of Light at Night on oxidative stress markers in Golden spiny mice (Acomys russatus) liver.

    PubMed

    Ashkenazi, Lilach; Haim, Abraham

    2013-07-01

    Light at Night (LAN) suppresses melatonin (MLT) production, and effects metabolism, hormone secretion, gene expression and enzyme activity. Changes in antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD), can be used as an indication for oxidative stress level. We assayed activity and expression of these enzymes in the liver of Acomys russatus exposed to LAN and treated with MLT. Short day (SD)-acclimated A. russatus, was exposed to 30min of LAN for two, seven or 21 nights. MLT impact was assessed simultaneously with two and seven nights of LAN exposure. GPx and SOD activities were measured. Gpx1 expression was evaluated by RT-PCR. There was a significant increase in GPx activity following LAN exposure for all acclimation durations, GPx activity was elevated after two nights of LAN and MLT treatment, Gpx1 expression was elevated by MLT after seven nights of LAN. SOD activity increased after two nights of LAN in MLT-treated A. russatus, GPx activity increased with the duration of LAN acclimation, indicating changes in liver redox status. Our results suggest that LAN is a stressor that influences oxidative stress. As in the other studies, MLT increases antioxidant activities, presumably attenuating stress response, in order to restore homeostasis.

  4. Interim-Night Integrated Goggle Head Tracking System (I-Nights). Volume 1. Ground Test Summary

    DTIC Science & Technology

    1992-08-01

    3 Figure 2. Honeywell I-NIGHTS System Drawing . . . . . . . . 4 Figure 3. Kaiser I-NIGHTS System Drawing . . . . . . . . . . 5 Figure 4. Spinal ...thoracolumbar spinal fracture during ejection seat use. The USAF use of the DRI to evaluate ejection seats is embodied in Military Specification: Seat Systems...probability of spinal injury. But, what WT/CG/force combinations are reasonably acceptable during ejection? The I-NIGHTS program helped establish an interim

  5. Chemiluminescents Light Up the Night.

    ERIC Educational Resources Information Center

    Dashiell, Judy

    1997-01-01

    Provides a general description of chemiluminescence and distinguishes between the two types of chemistry that contribute to our understanding of chemiluminescence: fluorescence and the excitation process. Presents an activity that explores the phenomenon. (DDR)

  6. Determining Light Pollution of the Global Sky: GLOBE at Night

    NASA Astrophysics Data System (ADS)

    Henderson, S.; Meymaris, K.; Ward, D.; Walker, C.; Russell, R.; Pompea, S.; Salisbury, D.

    2006-05-01

    GLOBE at Night is an international science event designed to observe and record the visible stars as a means of measuring light pollution in a given location. Increased and robust understanding of our environment requires learning opportunities that take place outside of the conventional K-12 classroom and beyond the confines of the school day. This hands-on learning activity extended the traditional classroom and school day last March with a week of nighttime sky observations involving teachers, students and their families. The quality of the night sky for stellar observations is impacted by several factors including human activities. By observing cloud cover and locating specific constellations in the sky, students from around the world learned how the lights in their community contribute to light pollution, exploring the relationship between science, technology and their society. Students learned that light pollution impacts more than just the visibility of stars at night. Lights at night impact both the biology and ecology of many species in our environment. Students were able to participate in this global scientific campaign by submitting their observations through an online database, allowing for authentic worldwide research and analysis by participating scientists. Students and their families learned how latitude and longitude coordinates provide a location system to map and analyze the observation data submitted from around the globe. The collected data is available online for use by students, teachers and scientists worldwide to assess how the quality of the night sky varies around the world. This session will share how students and scientists across the globe can explore and analyze the results of this exciting campaign. GLOBE at Night is a collaborative effort sponsored by The GLOBE Program, the National Optical Astronomy Observatory (NOAO), Centro de Apoyo a la Didactica de la Astronomia (CADIAS), Windows to the Universe, and ESRI. The GLOBE Program is

  7. Development of VIPER: a simulator for assessing vision performance of warfighters

    NASA Astrophysics Data System (ADS)

    Familoni, Jide; Thompson, Roger; Moyer, Steve; Mueller, Gregory; Williams, Tim; Nguyen, Hung-Quang; Espinola, Richard L.; Sia, Rose K.; Ryan, Denise S.; Rivers, Bruce A.

    2016-05-01

    activities. In the military context, in addition to reading road signs, this includes vision with night sensors and identification of objects of military interest. Once completed and validated, VIPER will be used to evaluate functional performance before and after refractive surgery. Results: This initial study was to prove the principle, and its results at the time of this publication were very preliminary. Nine Soldiers viewed visible-day and IR-day VIPER simulations with civilian and military targets, separately, at 10 and 30 miles/hour. Analyses were performed separately for visible and IR, and also aggregated. Only the civilian targets are discussed in this report. At 10 miles/hour, the population detected civilian road signs at an aggregated average of 90.11 +/- 64.20 m, and identified them at 26.93 +/- 22.27m. At 30 miles/hour, the corresponding distances were 103.03 +/- 58.81 and 26.26 +/- 8.55, respectively. Conclusion: This preliminary report proves the principle and suggests that VIPER could be a useful clinical tool in longitudinal assessment of functional vision in warfighters.

  8. Family Science Night: Changing Perceptions One Family at a Time

    NASA Technical Reports Server (NTRS)

    Pesnell, W. D.; Drobnes, E.; Mitchell, S.; Colina-Trujillo, M.

    2007-01-01

    If students are not encouraged to succeed in science, mathematics, and technology classes at school, efforts to improve the quality of content and teaching in these subjects may be futile. Parents and families are in a unique position to encourage children to enroll and achieve in these classes. The NASA Goddard Space Flight Center Family Science Night program invites middle school students and their families to explore the importance of science and technology in our daily lives by providing a venue for families to comfortably engage in learning activities that change their perception and understanding of science - making it more practical and approachable for participants of all ages. Family Science Night strives to change the way that students and their families participate in science, within the program and beyond.

  9. Export of carbon from chloroplasts at night

    SciTech Connect

    Schleucher, J.; Vanderveer, P.J.; Sharkey, T.D.

    1998-12-01

    Hexose export from chloroplasts at night has been inferred in previous studies of mutant and transgenic plants. The authors have tested whether hexose export is the normal route of carbon export from chloroplasts at night. The authors used nuclear magnetic resonance to distinguish glucose (Glc) made from hexose export and Glc made from triose export. Glc synthesized in vitro from fructose-6-phosphate in the presence of deuterium-labeled water had deuterium incorporated at C-2, whereas synthesis from triose phosphates caused C-2 through C-5 to become deuterated. In both tomato (Lycopersicon esculentum L.) and bean (phaseolus vulgaris L.), Glc from sucrose made at night in the presence of deuterium-enriched water was deuterated only in the C-2 position, indicating that >75% of carbon is exported as hexoses at night. In darkness the phosphate in the cytosol was 28 mM, whereas that in the chloroplasts was 5 mW, but hexose phosphates were 10-fold higher in the cytosol than in the chloroplasts. Therefore, hexose phosphates would not move out of chloroplasts without the input of energy. The authors conclude that most carbon leaves chloroplasts at night as Glc, maltose, or higher maltodextrins under normal conditions.

  10. FPGA Vision Data Architecture

    NASA Technical Reports Server (NTRS)

    Morfopoulos, Arin C.; Pham, Thang D.

    2013-01-01

    JPL has produced a series of FPGA (field programmable gate array) vision algorithms that were written with custom interfaces to get data in and out of each vision module. Each module has unique requirements on the data interface, and further vision modules are continually being developed, each with their own custom interfaces. Each memory module had also been designed for direct access to memory or to another memory module.

  11. A Night on the Nile.

    ERIC Educational Resources Information Center

    Hayes, Maureen E.; Heathwood, Neil

    1984-01-01

    Two New Rochelle, New York, teachers who developed a unit on ancient Egypt for gifted fifth and sixth grade students give tips on preparing interdisciplinary units which involve independent student research. Their unit incorporated social studies, science, language art, and mathematics activities. (PP)

  12. NightSkyLive.net: Bringing the Night Sky into Your Classroom

    NASA Astrophysics Data System (ADS)

    Nemiroff, R. J.; Night Sky Live

    2004-12-01

    Show your class a full live night sky with a single click. The Night Sky Live project now has 10 fisheye CONtinuous CAMeras (CONCAMs) deployed around the world that send live images of the night sky back to http://NightSkyLive.net every few minutes. Any classroom that has access to a web browser can see the current night sky, live, horizon to horizon, similar in depth to what the human eye can see, and annotated, above a major observatory somewhere in the world. Additionally, archived images and automatically generated movies show how the night sky appeared over the past night and the past year, and how it will likely appear above your student's heads tonight, all through the night. Stars, planets, and constellations are automatically labelled. In addition to live products, canned on-line tutorials for beginning students use archived NSL images to explain concepts such as diurnal motion and and demonstrate the transience of variable stars. Projects for more advanced undergraduates include using the automatically generated photometry files to follow the light curves of well known stars such as Polaris, Betelgeuse, and Alpha Centauri.

  13. Biomimetic machine vision system.

    PubMed

    Harman, William M; Barrett, Steven F; Wright, Cameron H G; Wilcox, Michael

    2005-01-01

    Real-time application of digital imaging for use in machine vision systems has proven to be prohibitive when used within control systems that employ low-power single processors without compromising the scope of vision or resolution of captured images. Development of a real-time machine analog vision system is the focus of research taking place at the University of Wyoming. This new vision system is based upon the biological vision system of the common house fly. Development of a single sensor is accomplished, representing a single facet of the fly's eye. This new sensor is then incorporated into an array of sensors capable of detecting objects and tracking motion in 2-D space. This system "preprocesses" incoming image data resulting in minimal data processing to determine the location of a target object. Due to the nature of the sensors in the array, hyperacuity is achieved thereby eliminating resolutions issues found in digital vision systems. In this paper, we will discuss the biological traits of the fly eye and the specific traits that led to the development of this machine vision system. We will also discuss the process of developing an analog based sensor that mimics the characteristics of interest in the biological vision system. This paper will conclude with a discussion of how an array of these sensors can be applied toward solving real-world machine vision issues.

  14. Vision Changes in Space

    NASA Video Gallery

    This Human Research Program 'Research to Outreach' video featuring NASA Clinical Translational Scientist Jennifer Fogarty explains the risk of vision impairment both during and after spaceflight, i...

  15. Artificial human vision camera

    NASA Astrophysics Data System (ADS)

    Goudou, J.-F.; Maggio, S.; Fagno, M.

    2014-10-01

    In this paper we present a real-time vision system modeling the human vision system. Our purpose is to inspire from human vision bio-mechanics to improve robotic capabilities for tasks such as objects detection and tracking. This work describes first the bio-mechanical discrepancies between human vision and classic cameras and the retinal processing stage that takes place in the eye, before the optic nerve. The second part describes our implementation of these principles on a 3-camera optical, mechanical and software model of the human eyes and associated bio-inspired attention model.

  16. Making Space Cool - Successful Outreach at Yuri's Night Stuttgart

    NASA Astrophysics Data System (ADS)

    Hill, Christine; Bretschneider, Jens; Nathanson, Emil; Grossmann, Agnes

    Yuri’s Night - also known as the “World Space Party” - is the annual celebration commemorating Gagarin’s historic flight on April 12, 1961, and the maiden voyage of the American space shuttle on April 12, 1981. It was created by young space enthusiasts in 2000 at the annual Space Generation Congress and was first celebrated in 2001, registering more than 60 events around the world from the start. Since then the interest in celebrating human spaceflight grew constantly to over 350 events across all seven continents in 2013. The honoring of Yuri Gagarin’s first spaceflight in Stuttgart started in 2007 and resulted in one of the largest events outside the US, with five parties following in 2008, 2009, 2010, 2012 and 2013. The Stuttgart event was originally organized as space party for an audience at the age of 20 and beyond including informative aspects at the afternoon and a following party far into the night. Since 2010 the focus of the Yuri’s Night Stuttgart is to bring awareness of space exploration to people of all ages, including particularly many participatory hands-on space activities for kids and families that attract hundreds of visitors every year. As much as Yuri’s Night is a worldwide party, the events in Stuttgart successfully concentrate on educational aspects that help to inspire new generations of space enthusiasts who will ultimately shape the future of space exploration. It is therefore not only a look back to one of the greatest achievements of the 20th Century, but it is also a look into the future: from multinational cooperation on the International Space Station to benefit of space flight to the introduction of the next generation of space technology. This paper will introduce the celebrations of Yuri’s Night in Stuttgart of the past four years and compare them to the early events. It provides a summary of the development of the Yuri’s Night including educational aspects, public relations and media attraction and gives

  17. Night sweats: it may be hemochromatosis.

    PubMed

    Murday, H K M; Rusli, F D; Blandy, C; Vollenhoven, B

    2016-08-01

    The aim of this case report is to show that hemochromatosis can present, unusually, with night sweats. At presentation, hemochromatosis often tends to have non-specific symptoms, making it easy to misdiagnose, especially if it presents with rare symptoms. Misdiagnosis of hemochromatosis can lead to lethal outcomes, given it can cause multiple organ dysfunctions if left untreated and hence the need to identify it early on. The case we present is a 41-year-old woman with previously undiagnosed hemochromatosis complaining of night sweats. She thought she was menopausal. The diagnosis of hemochromatosis was made solely on investigations given that she did not have any other symptoms other than night sweats. Her serum iron concentrations were within the normal range due to menstruation. It is uncommon for women to present with symptoms of hemochromatosis during their reproductive life since their iron concentration is kept within normal range through monthly menstrual bleeding.

  18. Solar power for the lunar night

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.

    1989-01-01

    Providing power over the 354 hour lunar night provides a considerable challenge to solar power concepts for a moonbase. Concepts are reviewed for providing night power for a solar powered moonbase. The categories of solutions considered are electrical storage, physical storage, transmitted power, and innovative concepts. Electrical storage is the most well-developed option. Less developed electrical storage options are capacitors and superconducting inductors. Physical storage options include storage of potential energy and storage of energy in flywheels. Thermal storage has potentially high energy/weight, but problems of conduction and radiation losses during the night need to be addressed. Transmitted power considers use of microwave or laser beams to transmit power either from orbit or directly from the Earth. Finally, innovative concepts proposed include reflecting light from orbital mirrors, locating the moonbase at a lunar pole, converting reflected Earthlight, or moving the moonbase to follow the sun.

  19. Night sky brightness measurement at PERMATApintar observatory

    NASA Astrophysics Data System (ADS)

    Azhar, A. D.; Gopir, G.; Kamil, W. M. A. Wan Mohd; Mohamad, N. S.; Azmi, N. Che

    2016-11-01

    One of the quality parameter of an astronomical site testing is sky brightness. We measure the night sky brightness over PERMATApintar Observatory to obtain the first preliminary sky brightness reading. The measurement is done by using an Unihedron Sky Quality Meter (SQM-LU) with a position pointing zenith. Six measurements have been done during the period of January to March 2016. The measurement is taken between approximately 7 p.m. to 11 p.m. on each of the night. The best (darken) night sky brightness reading is 19.54 mag/arcsec2 obtained on March 11th, 2016. The preliminary average reading of sky brightness is 17.20 mag/arcsec2. Comparison with previous similar measurement for the same type of area (suburban area) shows that our data is within the range of the sky brightness for suburban area, which is 19.5 to 20.7 mag/arcsec2.

  20. NVG adjustment methods, eyepiece focus settings, and vision

    NASA Astrophysics Data System (ADS)

    Van Arsdel, Richard; Baldwin, J. Bruce; Hausmann, Martha A.; Harrington, Lawrence K.; Craig, Jeffrey L.; Koepke, Corbin G.

    2006-05-01

    Several studies and many anecdotal reports indicate that aircrew members focus night vision goggle (NVG) eyepiece lenses to more negative powers than would be expected based on refractive error, presumably due to instrument myopia, "dark focus" myopia, and other factors. Excessive negative power stimulates accommodation, introducing risks from discomfort, fatigue, and blurred vision. Aircrew members are trained to employ specific adjustment techniques to minimize "over-minusing" of eyepiece lens powers, but those techniques are prone to error. The currently fielded AN/AVS-9 NVG (F4949) has a focus range of (+2.0) to (-6.0) diopters, and meets the needs of most aircrew. However, the new AN/AVS-10 NVG panoramic night vision goggle (PNVG) has a fixed focus of (-1.0) diopters due to engineering design constraints. Accessory snap-on lenses are available, but data are needed to optimize the distribution of lens powers to be acquired and maintained. This study involved the characterization of vision (visual acuity, perceived quality, and comfort) as a function of: 1) eyepiece focus setting using trial lenses; 2) F4949 eyepiece focus adjustments using a point source vs. a Hoffman 20/20 box; and 3) PNVG eyepiece lens selections using a lens bar vs. snap-on lens selections. Eight subjects with normal (20/20 corrected) vision ranging in age from 23 years to 49 participated in this study. The experiments were conducted in the Aerospace Vision Experimental Laboratory and the Dynamic Vision Assessment Facility at Wright Patterson AFB, Ohio using F4949 and PNVG devices with a custom-designed NVG-compatible computer-based visual acuity acquisition system.

  1. Health Impact Modelling of Active Travel Visions for England and Wales Using an Integrated Transport and Health Impact Modelling Tool (ITHIM)

    PubMed Central

    Woodcock, James; Givoni, Moshe; Morgan, Andrei Scott

    2013-01-01

    Background Achieving health benefits while reducing greenhouse gas emissions from transport offers a potential policy win-win; the magnitude of potential benefits, however, is likely to vary. This study uses an Integrated Transport and Health Impact Modelling tool (ITHIM) to evaluate the health and environmental impacts of high walking and cycling transport scenarios for English and Welsh urban areas outside London. Methods Three scenarios with increased walking and cycling and lower car use were generated based upon the Visions 2030 Walking and Cycling project. Changes to carbon dioxide emissions were estimated by environmental modelling. Health impact assessment modelling was used to estimate changes in Disability Adjusted Life Years (DALYs) resulting from changes in exposure to air pollution, road traffic injury risk, and physical activity. We compare the findings of the model with results generated using the World Health Organization's Health Economic Assessment of Transport (HEAT) tools. Results This study found considerable reductions in disease burden under all three scenarios, with the largest health benefits attributed to reductions in ischemic heart disease. The pathways that produced the largest benefits were, in order, physical activity, road traffic injuries, and air pollution. The choice of dose response relationship for physical activity had a large impact on the size of the benefits. Modelling the impact on all-cause mortality rather than through individual diseases suggested larger benefits. Using the best available evidence we found fewer road traffic injuries for all scenarios compared with baseline but alternative assumptions suggested potential increases. Conclusions Methods to estimate the health impacts from transport related physical activity and injury risk are in their infancy; this study has demonstrated an integration of transport and health impact modelling approaches. The findings add to the case for a move from car transport to

  2. The role of oscillatory brain activity in object processing and figure-ground segmentation in human vision.

    PubMed

    Kinsey, K; Anderson, S J; Hadjipapas, A; Holliday, I E

    2011-03-01

    The perception of an object as a single entity within a visual scene requires that its features are bound together and segregated from the background and/or other objects. Here, we used magnetoencephalography (MEG) to assess the hypothesis that coherent percepts may arise from the synchronized high frequency (gamma) activity between neurons that code features of the same object. We also assessed the role of low frequency (alpha, beta) activity in object processing. The target stimulus (i.e. object) was a small patch of a concentric grating of 3c/°, viewed eccentrically. The background stimulus was either a blank field or a concentric grating of 3c/° periodicity, viewed centrally. With patterned backgrounds, the target stimulus emerged--through rotation about its own centre--as a circular subsection of the background. Data were acquired using a 275-channel whole-head MEG system and analyzed using Synthetic Aperture Magnetometry (SAM), which allows one to generate images of task-related cortical oscillatory power changes within specific frequency bands. Significant oscillatory activity across a broad range of frequencies was evident at the V1/V2 border, and subsequent analyses were based on a virtual electrode at this location. When the target was presented in isolation, we observed that: (i) contralateral stimulation yielded a sustained power increase in gamma activity; and (ii) both contra- and ipsilateral stimulation yielded near identical transient power changes in alpha (and beta) activity. When the target was presented against a patterned background, we observed that: (i) contralateral stimulation yielded an increase in high-gamma (>55 Hz) power together with a decrease in low-gamma (40-55 Hz) power; and (ii) both contra- and ipsilateral stimulation yielded a transient decrease in alpha (and beta) activity, though the reduction tended to be greatest for contralateral stimulation. The opposing power changes across different regions of the gamma spectrum with

  3. Vision Sensors and Cameras

    NASA Astrophysics Data System (ADS)

    Hoefflinger, Bernd

    Silicon charge-coupled-device (CCD) imagers have been and are a specialty market ruled by a few companies for decades. Based on CMOS technologies, active-pixel sensors (APS) began to appear in 1990 at the 1 μm technology node. These pixels allow random access, global shutters, and they are compatible with focal-plane imaging systems combining sensing and first-level image processing. The progress towards smaller features and towards ultra-low leakage currents has provided reduced dark currents and μm-size pixels. All chips offer Mega-pixel resolution, and many have very high sensitivities equivalent to ASA 12.800. As a result, HDTV video cameras will become a commodity. Because charge-integration sensors suffer from a limited dynamic range, significant processing effort is spent on multiple exposure and piece-wise analog-digital conversion to reach ranges >10,000:1. The fundamental alternative is log-converting pixels with an eye-like response. This offers a range of almost a million to 1, constant contrast sensitivity and constant colors, important features in professional, technical and medical applications. 3D retino-morphic stacking of sensing and processing on top of each other is being revisited with sub-100 nm CMOS circuits and with TSV technology. With sensor outputs directly on top of neurons, neural focal-plane processing will regain momentum, and new levels of intelligent vision will be achieved. The industry push towards thinned wafers and TSV enables backside-illuminated and other pixels with a 100% fill-factor. 3D vision, which relies on stereo or on time-of-flight, high-speed circuitry, will also benefit from scaled-down CMOS technologies both because of their size as well as their higher speed.

  4. Autophagy supports color vision

    PubMed Central

    Zhou, Zhenqing; Vinberg, Frans; Schottler, Frank; Doggett, Teresa A; Kefalov, Vladimir J; Ferguson, Thomas A

    2015-01-01

    Cones comprise only a small portion of the photoreceptors in mammalian retinas. However, cones are vital for color vision and visual perception, and their loss severely diminishes the quality of life for patients with retinal degenerative diseases. Cones function in bright light and have higher demand for energy than rods; yet, the mechanisms that support the energy requirements of cones are poorly understood. One such pathway that potentially could sustain cones under basal and stress conditions is macroautophagy. We addressed the role of macroautophagy in cones by examining how the genetic block of this pathway affects the structural integrity, survival, and function of these neurons. We found that macroautophagy was not detectable in cones under normal conditions but was readily observed following 24 h of fasting. Consistent with this, starvation induced phosphorylation of AMPK specifically in cones indicating cellular starvation. Inhibiting macroautophagy in cones by deleting the essential macroautophagy gene Atg5 led to reduced cone function following starvation suggesting that cones are sensitive to systemic changes in nutrients and activate macroautophagy to maintain their function. ATG5-deficiency rendered cones susceptible to light-induced damage and caused accumulation of damaged mitochondria in the inner segments, shortening of the outer segments, and degeneration of all cone types, revealing the importance of mitophagy in supporting cone metabolic needs. Our results demonstrate that macroautophagy supports the function and long-term survival of cones providing for their unique metabolic requirements and resistance to stress. Targeting macroautophagy has the potential to preserve cone-mediated vision during retinal degenerative diseases. PMID:26292183

  5. Autophagy supports color vision.

    PubMed

    Zhou, Zhenqing; Vinberg, Frans; Schottler, Frank; Doggett, Teresa A; Kefalov, Vladimir J; Ferguson, Thomas A

    2015-01-01

    Cones comprise only a small portion of the photoreceptors in mammalian retinas. However, cones are vital for color vision and visual perception, and their loss severely diminishes the quality of life for patients with retinal degenerative diseases. Cones function in bright light and have higher demand for energy than rods; yet, the mechanisms that support the energy requirements of cones are poorly understood. One such pathway that potentially could sustain cones under basal and stress conditions is macroautophagy. We addressed the role of macroautophagy in cones by examining how the genetic block of this pathway affects the structural integrity, survival, and function of these neurons. We found that macroautophagy was not detectable in cones under normal conditions but was readily observed following 24 h of fasting. Consistent with this, starvation induced phosphorylation of AMPK specifically in cones indicating cellular starvation. Inhibiting macroautophagy in cones by deleting the essential macroautophagy gene Atg5 led to reduced cone function following starvation suggesting that cones are sensitive to systemic changes in nutrients and activate macroautophagy to maintain their function. ATG5-deficiency rendered cones susceptible to light-induced damage and caused accumulation of damaged mitochondria in the inner segments, shortening of the outer segments, and degeneration of all cone types, revealing the importance of mitophagy in supporting cone metabolic needs. Our results demonstrate that macroautophagy supports the function and long-term survival of cones providing for their unique metabolic requirements and resistance to stress. Targeting macroautophagy has the potential to preserve cone-mediated vision during retinal degenerative diseases.

  6. Requirements of an HMS/D for a night-flying helicopter

    NASA Astrophysics Data System (ADS)

    Boehm, Hans-Dieter V.; Schranner, R.

    1990-10-01

    Helicopter pilots prefer for the night-flying tasks a combination of electro-optical sensors with different physical principles in the Infra-Red (IR) and in the near IR spectrum: Thermal Imager (TI or FLIR), Night Vision Goggles (NVG) or Low Light Level Television (LLLTV) . The limits of these three sensors are in extreme darkness with less than 1 mLux illumination or in heavy rain, fog or snow with temperature differences below 0.1 K or with cross-over effects respectively. The development goal for the near future should be an integrated, lightweight helmet h a binocular display on the visor providing two or three sensor images. The paper describes operational requirements, human engineering aspects and the requirements of an integrated light-weight helmet with two NVG-tubes and two CRTs to display superimposed NVG and TI images with flight symbologies.

  7. Combined impacts of Black-crowned Night-Heron predation/disturbance and various management activities on Roseate Tern productivity in 2003, and testing of a video surveillance system for recording the diurnal and nocturnal behavior of terns and night-herons at Falkner Island, Stewart B. McKinney National Wildlife Refuge, Connecticut, in 2004: Report to U.S. Fish and Wildlife Service, Stewart B. McKinney National Wildlife Refuge, Westbrook, Connecticut and U.S. Fish and Wildlife Service, Region 5 Regional Office, Hadley, Massachusetts

    USGS Publications Warehouse

    Spendelow, J.A.; Kuter, M.

    2004-01-01

    night-herons and the behavior and productivity of the terns are affected by the activities of management personnel (or researchers) that may be moving around the island at night. The second objective is to develop new structures (or to modify existing ones) that can be used by adult Roseate Terns for nesting sites and/or by chicks as hiding sites so that tern eggs and chicks will be less susceptible to night-heron predation. Work on the development and comparative use of various man-made structures began prior to the start of the 2003 nesting season; work on the evaluation and testing of a video surveillance system to study the nocturnal behavior of the terns and night-herons began in June 2003. Reported here are (1) the results of work on the placement and use by Roseate Terns of several types of structures in different habitats, and (2) a description of the set-up, testing, and evaluation of a multi-camera video system to record tern and predator behavior during both day and night. Also given here is some additional information on other factors that affected the productivity of the Roseate Terns at FICT collected as part of the CRTMP which served as the underlying foundation for the additional work done with support of the 2003 Quick Response Funds.

  8. New Term, New Vision?

    ERIC Educational Resources Information Center

    Ravenhall, Mark

    2011-01-01

    During the affluent noughties it was sometimes said of government that it had "more visions than Mystic Meg and more pilots than British Airways". In 2011, the pilots, the pathfinders, the new initiatives are largely gone--implementation is the name of the game--but the visions remain. The latest one, as it affects adult learners, is in…

  9. INSIGHT: Vision & Leadership, 2002.

    ERIC Educational Resources Information Center

    McGraw, Tammy, Ed.

    2002-01-01

    This publication focuses on promising new and emerging technologies and what they might mean to the future of K-12 schools. Half of the volume contains articles devoted in some way to "Vision," and articles in the other half are under the heading of "Leadership." Contents in the "Vision" section include: "The…

  10. Why Vision 2020?

    ERIC Educational Resources Information Center

    Hinckley, June

    2000-01-01

    Discusses changes in technology, information, and people and the impact on music programs. The Vision 2020 project focuses on the future of music education. Addresses the events that created Vision 2020. Includes "The Housewright Declaration," a summarization of agreements from the Housewright Symposium on the Future of Music Education. (CMK)

  11. Color vision deficiencies

    NASA Astrophysics Data System (ADS)

    Vannorren, D.

    1982-04-01

    Congenital and acquired color vision defects are described in the context of physiological data. Light sources, photometry, color systems and test methods are described. A list of medicines is also presented. The practical social consequences of color vision deficiencies are discussed.

  12. Near Vision Test for Adults

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  13. Light Vision Color

    NASA Astrophysics Data System (ADS)

    Valberg, Arne

    2005-04-01

    Light Vision Color takes a well-balanced, interdisciplinary approach to our most important sensory system. The book successfully combines basics in vision sciences with recent developments from different areas such as neuroscience, biophysics, sensory psychology and philosophy. Originally published in 1998 this edition has been extensively revised and updated to include new chapters on clinical problems and eye diseases, low vision rehabilitation and the basic molecular biology and genetics of colour vision. Takes a broad interdisciplinary approach combining basics in vision sciences with the most recent developments in the area Includes an extensive list of technical terms and explanations to encourage student understanding Successfully brings together the most important areas of the subject in to one volume

  14. Color vision and dentistry.

    PubMed

    Wasson, W; Schuman, N

    1992-05-01

    Color vision is a critical component of restorative and esthetic dentistry, but dentists, as a group, do not have their color vision tested at any time during their careers. A study was undertaken to ascertain the color-vision status of practicing dental personnel at the University of Tennessee, College of Dentistry. One hundred fifty individuals, 75 men and 75 women, were screened. The results corroborated the existing medical data for the general population. It was found that 9.3% of the men and none of the women exhibited color-vision defect. Since most dentists are male, this study demonstrates an area of potential weakness for some practitioners. Once a color-vision problem is found, it is simple to remedy by employing a team approach to shade matching or mechanical means of matching shades (by the practitioner). No ethnic or racial distinctions were detected, although these have been reported in other studies.

  15. Panoramic stereo sphere vision

    NASA Astrophysics Data System (ADS)

    Feng, Weijia; Zhang, Baofeng; Röning, Juha; Zong, Xiaoning; Yi, Tian

    2013-01-01

    Conventional stereo vision systems have a small field of view (FOV) which limits their usefulness for certain applications. While panorama vision is able to "see" in all directions of the observation space, scene depth information is missed because of the mapping from 3D reference coordinates to 2D panoramic image. In this paper, we present an innovative vision system which builds by a special combined fish-eye lenses module, and is capable of producing 3D coordinate information from the whole global observation space and acquiring no blind area 360°×360° panoramic image simultaneously just using single vision equipment with one time static shooting. It is called Panoramic Stereo Sphere Vision (PSSV). We proposed the geometric model, mathematic model and parameters calibration method in this paper. Specifically, video surveillance, robotic autonomous navigation, virtual reality, driving assistance, multiple maneuvering target tracking, automatic mapping of environments and attitude estimation are some of the applications which will benefit from PSSV.

  16. (Computer) Vision without Sight

    PubMed Central

    Manduchi, Roberto; Coughlan, James

    2012-01-01

    Computer vision holds great promise for helping persons with blindness or visual impairments (VI) to interpret and explore the visual world. To this end, it is worthwhile to assess the situation critically by understanding the actual needs of the VI population and which of these needs might be addressed by computer vision. This article reviews the types of assistive technology application areas that have already been developed for VI, and the possible roles that computer vision can play in facilitating these applications. We discuss how appropriate user interfaces are designed to translate the output of computer vision algorithms into information that the user can quickly and safely act upon, and how system-level characteristics affect the overall usability of an assistive technology. Finally, we conclude by highlighting a few novel and intriguing areas of application of computer vision to assistive technology. PMID:22815563

  17. Is there a First Night Effect on Sleep Bruxism? A Sleep Laboratory Study

    PubMed Central

    Hasegawa, Yoko; Lavigne, Gilles; Rompré, Pierre; Kato, Takafumi; Urade, Masahiro; Huynh, Nelly

    2013-01-01

    Study Objectives: Sleep bruxism (SB) is reported to vary in frequency over time. The aim of this study was to assess the first night effect on SB. Methods: A retrospective polysomnographic (PSG) analysis was performed of data from a sample of SB patients (12 females, 4 males; age range: 17-39 years) recorded in a sleep laboratory over 2 consecutive nights. Sleep parameters and jaw muscle activity variables (i.e., rhythmic masticatory muscle activity [RMMA]) for SB were quantified and compared between the 2 nights. Subjects were classified into groups according to severity of RMMA frequency, such as low frequency (2-4 episodes/h and/or < 25 bursts/h) and moderate-high frequency (≥ 4 episodes/h and ≥ 25 bursts/h). Results: Overall, no first night effects were found for most sleep variables. However, total sleep time, sleep efficiency, and stage transitions showed significant time and group interactions (repeated measures ANOVAs, p ≤ 0.05). The RMMA episode index did not differ between the 2 nights, whereas the second night showed significantly higher burst index, bruxism time index, and mean burst duration (repeated measure ANOVAs, p ≤ 0.05). Five patients of 8 in the low frequency group were classified into the moderate-high frequency group on the second night, whereas only one patient in the moderate-high frequency group moved to the low frequency group. Conclusions: The results showed no overall first night effect on severity of RMMA frequency in young and healthy patients with SB. In clinical practice, one-night sleep recording may be sufficient for moderate-high frequency SB patients. However, low RMMA frequency in the first night could be confirmed by a second night based on the patient's medical and dental history. Citation: Hasegawa Y; Lavigne G; Rompré P; Kato T; Urade M; Huynh N. Is there a first night effect on sleep bruxism? A sleep laboratory study. J Clin Sleep Med 2013;9(11):1139-1145. PMID:24235894

  18. Night-to-Night Sleep Variability in Older Adults with and Without Chronic Insomnia

    PubMed Central

    Buysse, Daniel J.; Cheng, Yu; Germain, Anne; Moul, Douglas E.; Franzen, Peter L.; Fletcher, Mary; Monk, Timothy H.

    2009-01-01

    Objectives 1) To quantify night-to-night variability in sleep behaviors and sleep measures among older chronic insomnia (CI) subjects and non-insomnia (NI) controls; 2) to investigate systematic temporal patterns of sleep behaviors and sleep measures across nights; and 3) to examine clinical correlates of sleep variability. Methods Sixty-one older adults with CI (71.4 years old, 67%F) and 31 older adults with NI (70.7 years old, 65%F) completed questionnaires and kept sleep diaries and wore wrist actigraphs for two weeks. Mixed models were used to estimate within-subject mean and standard deviation values; these were then compared across groups. Mixed models were also used to determine associations across nights of sleep measures. Results CI and NI differed on mean values for clinical ratings and sleep diary measures, but not for actigraphy measures. CI also showed significantly greater variability than NI on most sleep diary measures and on actigraphically-measured wakefulness after sleep onset (WASO) and sleep efficiency. Among CI, neither diary nor actigraphy measures from one night correlated with values from the previous night. Diary WASO and sleep time and actigraphy sleep latency and sleep time, however, positively correlated with values from the previous two nights. Variability measures were not correlated with other global clinical measures among CI. Conclusions Compared to NI, older adults with CI report worse sleep and greater night-tonight variability, which was confirmed with actigraphy. There was little evidence for positive or negative correlation of sleep measures across nights. Variability of sleep may be an important target for insomnia treatments. PMID:19962939

  19. Why Is the Sky Dark at Night?

    ERIC Educational Resources Information Center

    Stinner, Arthur

    2014-01-01

    The puzzle as to just why the sky is dark at night, given that there are so many stars, has been around at least since Newton. This article summarizes six cosmological models that have been used to attempt to give an account of this puzzle including the Copernican universe, the Newton-Halley universe, the nineteenth century "one galaxy"…

  20. Analysis of Thursday Night NFL Winning Margins

    ERIC Educational Resources Information Center

    Vaughan, Timothy S.

    2015-01-01

    This paper introduces a dataset and associated analysis of the scores of National Football League (NFL) games over the 2012, 2013, and first five weeks of the 2014 season. In the face of current media attention to "lopsided" scores in Thursday night games in the early part of the 2014 season, t-test results indicate no statistically…

  1. HH-60D night hawk helicopter

    NASA Technical Reports Server (NTRS)

    Richardson, C. S.

    1984-01-01

    Fundamental development issues, system requirements and improvements are reported for the HH-60D night hawk helicopter. The HH-60D mission requirements are for combat search and rescue (aerospace rescue and recovery service user based at Scott AFB) and special operations (special operations forces based at Hurlburt AFB). Cockpit design, computer architecture and software are described in detail.

  2. Ecological consequences of artificial night lighting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This edited volume is the best source for the increasingly recognized impact of artificial night lighting on the living world. Fifteen chapters cover effects of artificial lighting on mammals, birds, reptiles, amphibians, fishes, invertebrates (mostly insects), and plants. The book was an outgrowt...

  3. Things That Go "Peent" in the Night.

    ERIC Educational Resources Information Center

    Neidich, Carole Louise

    1981-01-01

    Describes early spring night field trips by two naturalists and ten adults, armed with cameras and flashlights, in search of Spotted Salamanders performing ritual mating dances. Although dancing salamanders proved elusive, their habits and those of other pond life were examined and Spring American Woodcock nuptial flights were observed. (NEC)

  4. Education in the Night: A Serious Separation.

    ERIC Educational Resources Information Center

    Manu'atu, Linita; Kepa, Tangiwai Mere Appleton

    Education is one of the social institutions manipulated by New Zealand's European people to establish and perpetuate a painfully fragmented society. Po Ako is a community-based educational project where immigrant teachers, parents, and children from Tonga educate themselves at night about their own culture to better understand themselves and their…

  5. Urban planning and traffic safety at night

    NASA Astrophysics Data System (ADS)

    Ispas, N.; Trusca, D.

    2016-08-01

    Urban planning including traffic signs serve vital functions, providing road users with regulatory, warning and guidance information about the roadway and surrounding environment. There are a large number of signs and even more guidelines on how these signs should be designed, installed, and maintained in concordance with on road surface traffic signs. More requirements for signs are made for night urban traffic, including appearance (size, shape, colour), placement (height, lateral, and longitudinal), maintenance (visibility, position, damage) and signs light and retroreflective. In the night, traffic signs visibility can interact by on pedestrian visibility and diminish urban traffic safety. The main aim of this paper are the scientific determination of an urban specific zone visibility for evaluate at night real conditions in case of a traffic accident in the Braşov city area. The night visibility study was made using PC-Rect version 4.2. Other goal of the paper was to modify some urban planning solution in order to increase the urban safety in Brașov.

  6. GLOBE at Night: a Worldwide Citizen-Science Program to Increase Awareness of Light Pollution by Measuring Night Sky Brightness

    NASA Astrophysics Data System (ADS)

    Walker, C. E.; Pompea, S. M.

    2011-12-01

    The emphasis in the international citizen-science, star-hunting campaign, GLOBE at Night, is in bringing awareness to the public on issues of light pollution. Light pollution threatens not only observatory sites and our "right to starlight", but can affect energy consumption, wildlife and health. GLOBE at Night has successfully reached a few 100,000 citizen-scientists. What has contributed to its success? Foundational resources are available to facilitate the public's participation in promoting dark skies awareness. The GLOBE at Night website explains clearly the simple-to-participate-in 5 step program and offers background information and interactive games on key concepts. To promote the campaign via popular social media, GLOBE at Night created Facebook and Twitter pages. The program has been expanded to include trainings of the general public, but especially educators in schools, museums and science centers, in unique ways. Education kits for dark skies awareness have been distributed at the training workshops. The kit includes material for a light shielding demonstration, a digital Sky Quality Meter and "Dark Skies Rangers" activities. The activities are on how unshielded light wastes energy, how light pollution affects wildlife and how one can participate in a citizen-science star-hunt like GLOBE at Night. To increase participation in the 2011 campaign, children and adults submitted their sky brightness measurements in real time with smart phones or tablets using the web application at www.globeatnight.org/webapp/. With smart phones and tablets, the location, date and time register automatically. For those without smart mobile devices, user-friendly tools on the GLOBE at Night report page were reconfigured to determine latitude and longitude more easily and accurately. As a proto-type for taking multiple measurements, people in Tucson found it easy to adopt a street and take measurements every mile for the length of the street. The grid of measurements

  7. Extending the Cortical Grasping Network: Pre-supplementary Motor Neuron Activity During Vision and Grasping of Objects

    PubMed Central

    Lanzilotto, Marco; Livi, Alessandro; Maranesi, Monica; Gerbella, Marzio; Barz, Falk; Ruther, Patrick; Fogassi, Leonardo; Rizzolatti, Giacomo; Bonini, Luca

    2016-01-01

    Grasping relies on a network of parieto-frontal areas lying on the dorsolateral and dorsomedial parts of the hemispheres. However, the initiation and sequencing of voluntary actions also requires the contribution of mesial premotor regions, particularly the pre-supplementary motor area F6. We recorded 233 F6 neurons from 2 monkeys with chronic linear multishank neural probes during reaching–grasping visuomotor tasks. We showed that F6 neurons play a role in the control of forelimb movements and some of them (26%) exhibit visual and/or motor specificity for the target object. Interestingly, area F6 neurons form 2 functionally distinct populations, showing either visually-triggered or movement-related bursts of activity, in contrast to the sustained visual-to-motor activity displayed by ventral premotor area F5 neurons recorded in the same animals and with the same task during previous studies. These findings suggest that F6 plays a role in object grasping and extend existing models of the cortical grasping network. PMID:27733538

  8. Extending the Cortical Grasping Network: Pre-supplementary Motor Neuron Activity During Vision and Grasping of Objects.

    PubMed

    Lanzilotto, Marco; Livi, Alessandro; Maranesi, Monica; Gerbella, Marzio; Barz, Falk; Ruther, Patrick; Fogassi, Leonardo; Rizzolatti, Giacomo; Bonini, Luca

    2016-12-01

    Grasping relies on a network of parieto-frontal areas lying on the dorsolateral and dorsomedial parts of the hemispheres. However, the initiation and sequencing of voluntary actions also requires the contribution of mesial premotor regions, particularly the pre-supplementary motor area F6. We recorded 233 F6 neurons from 2 monkeys with chronic linear multishank neural probes during reaching-grasping visuomotor tasks. We showed that F6 neurons play a role in the control of forelimb movements and some of them (26%) exhibit visual and/or motor specificity for the target object. Interestingly, area F6 neurons form 2 functionally distinct populations, showing either visually-triggered or movement-related bursts of activity, in contrast to the sustained visual-to-motor activity displayed by ventral premotor area F5 neurons recorded in the same animals and with the same task during previous studies. These findings suggest that F6 plays a role in object grasping and extend existing models of the cortical grasping network.

  9. Literature and information in vision care and vision science.

    PubMed

    Goss, David A

    2008-11-01

    The explosion of information in vision care and vision science makes keeping up with the literature and information in the field challenging. This report examines the nature of literature and information in vision care and vision science. A variety of topics are discussed, including the general nature of scientific and clinical journals, journals in vision science and vision care, resources available for searches for literature and information, and issues involved in the evaluation of journals and other information sources. Aspects of the application of citation analysis to vision care and vision science are reviewed, and a new citation analysis of a leading textbook in vision care (Borish's Clinical Refraction) is presented. This report is directed toward anyone who wants to be more informed about the literature of vision care and vision science, whether they are students, clinicians, educators, or librarians.

  10. Exercise effects on night-to-night fluctuations in self-rated sleep among older adults with sleep complaints.

    PubMed

    Buman, Matthew P; Hekler, Eric B; Bliwise, Donald L; King, Abby C

    2011-03-01

    Sleep interventions have rarely explored reductions in night-to-night fluctuations [i.e. intra-individual variability (IIV)] in sleep, despite the negative impacts of such fluctuations on affective states and cognitive and physical symptoms. In a community-based randomized controlled trial we evaluated whether physical exercise reduced IIV in self-rated sleep outcomes among middle-aged and older adults with sleep complaints. Under-active adults 55 years and older (n = 66, 67% women) with mild to moderate sleep complaints were randomized to 12 months of a moderate-intensity endurance exercise (n = 36) or a health education control group (n = 30). Daily sleep logs, Pittsburgh Sleep Quality Index (PSQI) and in-home polysomnographic sleep recordings (PSG) were collected at baseline, 6 months and 12 months. Sleep log-derived means and IIV were computed for sleep-onset latency (SOL), time in bed, feeling rested in the morning, number of nighttime awakenings, and wake after final awakening (WAFA). Using intent-to-treat methods, at 6 months no differences in IIV were observed by group. At 12 months, SOL-based IIV was reduced in the exercise group compared with the control (difference = 23.11, 95% CI: 3.04-47.18, P = 0.025, Cohen's d = 0.57). This change occurred without mean-level or IIV changes in sleep-wake schedules. For all sleep variables, except SOL and WAFA, IIV changes and mean-level changes in each variable were negatively correlated (r = -0.312 to -0.691, P < 0.05). Sleep log-derived IIV changes were modestly correlated with mean-level PSQI and PSG-based changes at 12 months. Twelve months of moderate-intensity exercise reduced night-to-night fluctuations in self-rated time to fall asleep, and this relationship was independent of mean-level time to fall asleep.

  11. Mixing processes within the polar night jet

    NASA Technical Reports Server (NTRS)

    Pierce, R. Bradley; Fairlie, T. Duncan; Grose, William L.; Swinbank, Richard; O'Neill, Alan

    1994-01-01

    Lagrangian material line simulations are performed using U.K. Meteorological Office simulated winds and temperatures to examine mixing processes in the middle- and lower-stratospheric polar night jet during the 1992 Southern Hemisphere spring and Northern Hemisphere winter. The Lagrangian simulations are undertaken to provide insight into the effects of mixing within the polar night jet on observations of the polar vortex made by instruments onboard the Upper Atmosphere Research Satellite (UARS) during these periods. A moderate to strong kinematic barrier to large-scale isentropic exchange, similar to the barrier identified in General Circulation Model (GCM) simulations, is identified during both of these periods. Characteristic timescales for mixing by large-scale isentropic motions within the polar night jet range from 20 days in the Southern Hemisphere lower stratosphere to years in the Northern Hemisphere middle stratosphere. The long mixing timescales found in the Northern Hemisphere polar night jet do not persist. Instead, the Northern Hemisphere kinematic barriers are broken down as part of the large-scale stratospheric response to a strong tropospheric blocking event. A series of Lagrangian experiments are conducted to investigate the sensitivity of the kinematic barrier to diabatic effects and to small-scale inertial gravity wave motions. Differential diabatic descent is found to have a significant impact on mixing processes within the Southern Hemisphere middle-stratospheric jet core. The interaction between small-scale displacements by idealized, inertial gravity waves and the large-scale flow is found to have a significant impact on mixing within the polar night jet in both hemispheres. These sensitivity experiments suggest that scales of motion that are unresolved in global assimilated datasets may contribute to mass exchange across the kinematic barrier to large-scale isentropic motion.

  12. Evolution of the ATLAS Nightly Build System

    NASA Astrophysics Data System (ADS)

    Undrus, A.

    2012-12-01

    The ATLAS Nightly Build System is a major component in the ATLAS collaborative software organization, validation, and code approval scheme. For over 10 years of development it has evolved into a factory for automatic release production and grid distribution. The 50 multi-platform branches of ATLAS releases provide vast opportunities for testing new packages, verification of patches to existing software, and migration to new platforms and compilers for ATLAS code that currently contains 2200 packages with 4 million C++ and 1.4 million python scripting lines written by about 1000 developers. Recent development was focused on the integration of ATLAS Nightly Build and Installation systems. The nightly releases are distributed and validated and some are transformed into stable releases used for data processing worldwide. The ATLAS Nightly System is managed by the NICOS control tool on a computing farm with 50 powerful multiprocessor nodes. NICOS provides the fully automated framework for the release builds, testing, and creation of distribution kits. The ATN testing framework of the Nightly System runs unit and integration tests in parallel suites, fully utilizing the resources of multi-core machines, and provides the first results even before compilations complete. The NICOS error detection system is based on several techniques and classifies the compilation and test errors according to their severity. It is periodically tuned to place greater emphasis on certain software defects by highlighting the problems on NICOS web pages and sending automatic e-mail notifications to responsible developers. These and other recent developments will be presented and future plans will be described.

  13. Single-unit activity during natural vision: diversity, consistency, and spatial sensitivity among AF face patch neurons.

    PubMed

    McMahon, David B T; Russ, Brian E; Elnaiem, Heba D; Kurnikova, Anastasia I; Leopold, David A

    2015-04-08

    Several visual areas within the STS of the macaque brain respond strongly to faces and other biological stimuli. Determining the principles that govern neural responses in this region has proven challenging, due in part to the inherently complex stimulus domain of dynamic biological stimuli that are not captured by an easily parameterized stimulus set. Here we investigated neural responses in one fMRI-defined face patch in the anterior fundus (AF) of the STS while macaques freely view complex videos rich with natural social content. Longitudinal single-unit recordings allowed for the accumulation of each neuron's responses to repeated video presentations across sessions. We found that individual neurons, while diverse in their response patterns, were consistently and deterministically driven by the video content. We used principal component analysis to compute a family of eigenneurons, which summarized 24% of the shared population activity in the first two components. We found that the most prominent component of AF activity reflected an interaction between visible body region and scene layout. Close-up shots of faces elicited the strongest neural responses, whereas far away shots of faces or close-up shots of hindquarters elicited weak or inhibitory responses. Sensitivity to the apparent proximity of faces was also observed in gamma band local field potential. This category-selective sensitivity to spatial scale, together with the known exchange of anatomical projections of this area with regions involved in visuospatial analysis, suggests that the AF face patch may be specialized in aspects of face perception that pertain to the layout of a social scene.

  14. Simulations of Keratoconus Patient Vision with Optical Eye Modeling

    NASA Astrophysics Data System (ADS)

    Tan, Bo; Chen, Ying-Ling; Lewis, J. W. L.; Shi, Lei; Wang, Ming

    2007-11-01

    Keratoconus (KC) is an eye condition that involves progressive corneal thinning. Pushed by the intraocular pressure, the weakened cornea bulges outward and creates an irregular surface shape. The result is degraded vision that is difficult to correct with regular eye glasses or contact lens. In this study we use the optical lens design software, ZeMax, and patient data including cornea topography and refraction prescription to construct KC eye models. The variation of KC ``cone height'' on the cornea is used to simulate KC progression. The consequent patients' night vision and Snellen letter chart vision at 20 feet are simulated using these anatomically accurate 3-dimensional models. 100 million rays are traced for each image simulation. Animated results illustrate the change of KC visual acuity with the progression of disease. This simulation technique provides a comprehensive tool for medical training and patient consultation/education.

  15. Spatiochromatic model of vision

    NASA Astrophysics Data System (ADS)

    Moorhead, Ian R.

    1996-04-01

    A computer model of human spatiochromatic vision, based on the scheme proposed by De Valois and De Valois has been developed. The implementation of the model enables true color 2-D images to be processed. The input consists of cone signals at each pixel. Subsequent levels of the model are represented by arrays of activity corresponding to the equivalent neural activity. The implementation allows the behavior of different stages of the model -- retinal and cortical -- to be studied with different varieties of spatial and chromatic stimuli of any complexity. In addition the model is extensible to allow different types of neural mechanisms and cortical demultiplexing processes to be incorporated. As well as providing qualitative insight into the operation of the different stages of the model the implementation also permits quantitative predictions to be made. Both increment threshold and hue naming results are predicted by the model, but the accuracy of these predictions is contingent upon an appropriate choice of adaptation state at the retinal cone and ganglion cell level.

  16. Vision, eye disease, and art: 2015 Keeler Lecture

    PubMed Central

    Marmor, M F

    2016-01-01

    The purpose of this study was to examine normal vision and eye disease in relation to art. Ophthalmology cannot explain art, but vision is a tool for artists and its normal and abnormal characteristics may influence what an artist can do. The retina codes for contrast, and the impact of this is evident throughout art history from Asian brush painting, to Renaissance chiaroscuro, to Op Art. Art exists, and can portray day or night, only because of the way retina adjusts to light. Color processing is complex, but artists have exploited it to create shimmer (Seurat, Op Art), or to disconnect color from form (fauvists, expressionists, Andy Warhol). It is hazardous to diagnose eye disease from an artist's work, because artists have license to create as they wish. El Greco was not astigmatic; Monet was not myopic; Turner did not have cataracts. But when eye disease is documented, the effects can be analyzed. Color-blind artists limit their palette to ambers and blues, and avoid greens. Dense brown cataracts destroy color distinctions, and Monet's late canvases (before surgery) showed strange and intense uses of color. Degas had failing vision for 40 years, and his pastels grew coarser and coarser. He may have continued working because his blurred vision smoothed over the rough work. This paper can barely touch upon the complexity of either vision or art. However, it demonstrates some ways in which understanding vision and eye disease give insight into art, and thereby an appreciation of both art and ophthalmology. PMID:26563659

  17. Vision, eye disease, and art: 2015 Keeler Lecture.

    PubMed

    Marmor, M F

    2016-02-01

    The purpose of this study was to examine normal vision and eye disease in relation to art. Ophthalmology cannot explain art, but vision is a tool for artists and its normal and abnormal characteristics may influence what an artist can do. The retina codes for contrast, and the impact of this is evident throughout art history from Asian brush painting, to Renaissance chiaroscuro, to Op Art. Art exists, and can portray day or night, only because of the way retina adjusts to light. Color processing is complex, but artists have exploited it to create shimmer (Seurat, Op Art), or to disconnect color from form (fauvists, expressionists, Andy Warhol). It is hazardous to diagnose eye disease from an artist's work, because artists have license to create as they wish. El Greco was not astigmatic; Monet was not myopic; Turner did not have cataracts. But when eye disease is documented, the effects can be analyzed. Color-blind artists limit their palette to ambers and blues, and avoid greens. Dense brown cataracts destroy color distinctions, and Monet's late canvases (before surgery) showed strange and intense uses of color. Degas had failing vision for 40 years, and his pastels grew coarser and coarser. He may have continued working because his blurred vision smoothed over the rough work. This paper can barely touch upon the complexity of either vision or art. However, it demonstrates some ways in which understanding vision and eye disease give insight into art, and thereby an appreciation of both art and ophthalmology.

  18. Three-dimensional motion estimation using genetic algorithms from image sequence in an active stereo vision system

    NASA Astrophysics Data System (ADS)

    Dipanda, Albert; Ajot, Jerome; Woo, Sanghyuk

    2003-06-01

    This paper proposes a method for estimating 3D rigid motion parameters from an image sequence of a moving object. The 3D surface measurement is achieved using an active stereovision system composed of a camera and a light projector, which illuminates objects to be analyzed by a pyramid-shaped laser beam. By associating the laser rays and the spots in the 2D image, the 3D points corresponding to these spots are reconstructed. Each image of the sequence provides a set of 3D points, which is modeled by a B-spline surface. Therefore, estimating the motion between two images of the sequence boils down to matching two B-spline surfaces. We consider the matching environment as an optimization problem and find the optimal solution using Genetic Algorithms. A chromosome is encoded by concatenating six binary coded parameters, the three angles of rotation and the x-axis, y-axis and z-axis translations. We have defined an original fitness function to calculate the similarity measure between two surfaces. The matching process is performed iteratively: the number of points to be matched grows as the process advances and results are refined until convergence. Experimental results with a real image sequence are presented to show the effectiveness of the method.

  19. [Possibilities and limits of sleep recovery for night-nursing workers].

    PubMed

    de Medeiros, Soraya Maria; de Macêdo, Maria Lúcia Azevedo Ferreira; de Oliveira, Jonas Sâmi Albuquerque; Ribeiro, Laiane Medeiros

    2009-03-01

    The present study had the objective of investigating the possibilities/limits of sleep recovery in women workers with medium level in nursing that develop their activities in night shifts in a first-aid clinic at a public hospital in Natal, Rio Grande do Norte, Brazil. This was an analytic study, with a qualitative approach which used the technique of thematic oral history Fifteen women workers with medium level in nursing were interviewed. The following empirical categories were defined: night shift work and night sleep and night rest at work environment Physiological and psychological sufferings are evident on their speech as well as what the lack of sleep causes in health and personal life of these women workers, making the overload of work clear and also the sociocultural imperfections of feminine gender

  20. Vision Voice: A Multimedia Exploration of Diabetes and Vision Loss in East Harlem

    PubMed Central

    Ives, Brett; Nedelman, Michael; Redwood, Charysse; Ramos, Michelle A.; Hughson-Andrade, Jessica; Hernandez, Evelyn; Jordan, Dioris; Horowitz, Carol R.

    2016-01-01

    Background East Harlem, New York, is a community actively struggling with diabetes and its complications, including vision-related conditions that can affect many aspects of daily life. Objectives Vision Voice was a qualitative community-based participatory research (CBPR) study that intended to better understand the needs and experiences of people living with diabetes, other comorbid chronic illnesses, and vision loss in East Harlem. Methods Using photovoice methodology, four participants took photographs, convened to review their photographs, and determined overarching themes for the group’s collective body of work. Lessons Learned Identified themes included effect of decreased vision function on personal independence/mobility and self-management of chronic conditions and the importance of informing community members and health care providers about these issues. The team next created a documentary film that further develops the narratives of the photovoice participants. Conclusions The Vision Voice photovoice project was an effective tool to assess community needs, educate and raise awareness. PMID:26548784