Science.gov

Sample records for instant stereoscopic tomography

  1. Stereoscopic vascular models of the head and neck: A computed tomography angiography visualization.

    PubMed

    Cui, Dongmei; Lynch, James C; Smith, Andrew D; Wilson, Timothy D; Lehman, Michael N

    2016-01-01

    Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching anatomy includes use of computed tomography angiography (CTA) images of the head and neck to create clinically relevant 3D stereoscopic virtual models. These high resolution images of the arteries can be used in unique and innovative ways to create 3D virtual models of the vasculature as a tool for teaching anatomy. Blood vessel 3D models are presented stereoscopically in a virtual reality environment, can be rotated 360° in all axes, and magnified according to need. In addition, flexible views of internal structures are possible. Images are displayed in a stereoscopic mode, and students view images in a small theater-like classroom while wearing polarized 3D glasses. Reconstructed 3D models enable students to visualize vascular structures with clinically relevant anatomical variations in the head and neck and appreciate spatial relationships among the blood vessels, the skull and the skin. © 2015 American Association of Anatomists.

  2. Novel microscope-integrated stereoscopic heads-up display for intrasurgical optical coherence tomography

    PubMed Central

    Shen, Liangbo; Carrasco-Zevallos, Oscar; Keller, Brenton; Viehland, Christian; Waterman, Gar; Hahn, Paul S.; Kuo, Anthony N.; Toth, Cynthia A.; Izatt, Joseph A.

    2016-01-01

    Intra-operative optical coherence tomography (OCT) requires a display technology which allows surgeons to visualize OCT data without disrupting surgery. Previous research and commercial intrasurgical OCT systems have integrated heads-up display (HUD) systems into surgical microscopes to provide monoscopic viewing of OCT data through one microscope ocular. To take full advantage of our previously reported real-time volumetric microscope-integrated OCT (4D MIOCT) system, we describe a stereoscopic HUD which projects a stereo pair of OCT volume renderings into both oculars simultaneously. The stereoscopic HUD uses a novel optical design employing spatial multiplexing to project dual OCT volume renderings utilizing a single micro-display. The optical performance of the surgical microscope with the HUD was quantitatively characterized and the addition of the HUD was found not to substantially effect the resolution, field of view, or pincushion distortion of the operating microscope. In a pilot depth perception subject study, five ophthalmic surgeons completed a pre-set dexterity task with 50.0% (SD = 37.3%) higher success rate and in 35.0% (SD = 24.8%) less time on average with stereoscopic OCT vision compared to monoscopic OCT vision. Preliminary experience using the HUD in 40 vitreo-retinal human surgeries by five ophthalmic surgeons is reported, in which all surgeons reported that the HUD did not alter their normal view of surgery and that live surgical maneuvers were readily visible in displayed stereoscopic OCT volumes. PMID:27231616

  3. Novel microscope-integrated stereoscopic heads-up display for intrasurgical optical coherence tomography.

    PubMed

    Shen, Liangbo; Carrasco-Zevallos, Oscar; Keller, Brenton; Viehland, Christian; Waterman, Gar; Hahn, Paul S; Kuo, Anthony N; Toth, Cynthia A; Izatt, Joseph A

    2016-05-01

    Intra-operative optical coherence tomography (OCT) requires a display technology which allows surgeons to visualize OCT data without disrupting surgery. Previous research and commercial intrasurgical OCT systems have integrated heads-up display (HUD) systems into surgical microscopes to provide monoscopic viewing of OCT data through one microscope ocular. To take full advantage of our previously reported real-time volumetric microscope-integrated OCT (4D MIOCT) system, we describe a stereoscopic HUD which projects a stereo pair of OCT volume renderings into both oculars simultaneously. The stereoscopic HUD uses a novel optical design employing spatial multiplexing to project dual OCT volume renderings utilizing a single micro-display. The optical performance of the surgical microscope with the HUD was quantitatively characterized and the addition of the HUD was found not to substantially effect the resolution, field of view, or pincushion distortion of the operating microscope. In a pilot depth perception subject study, five ophthalmic surgeons completed a pre-set dexterity task with 50.0% (SD = 37.3%) higher success rate and in 35.0% (SD = 24.8%) less time on average with stereoscopic OCT vision compared to monoscopic OCT vision. Preliminary experience using the HUD in 40 vitreo-retinal human surgeries by five ophthalmic surgeons is reported, in which all surgeons reported that the HUD did not alter their normal view of surgery and that live surgical maneuvers were readily visible in displayed stereoscopic OCT volumes.

  4. Stereoscopic Vascular Models of the Head and Neck: A Computed Tomography Angiography Visualization

    ERIC Educational Resources Information Center

    Cui, Dongmei; Lynch, James C.; Smith, Andrew D.; Wilson, Timothy D.; Lehman, Michael N.

    2016-01-01

    Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching…

  5. Stereoscopic Vascular Models of the Head and Neck: A Computed Tomography Angiography Visualization

    ERIC Educational Resources Information Center

    Cui, Dongmei; Lynch, James C.; Smith, Andrew D.; Wilson, Timothy D.; Lehman, Michael N.

    2016-01-01

    Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching…

  6. Novel and quick coronary image analysis by instant stent-accentuated three-dimensional optical coherence tomography system in catheterization laboratory.

    PubMed

    Nakao, Fumiaki; Ueda, Tooru; Nishimura, Shigehiko; Uchinoumi, Hitoshi; Kanemoto, Masashi; Tanaka, Nobuaki; Fujii, Takashi

    2013-07-01

    In order to confirm the relation between stent struts and the jailed side branch (SB), the actual wire re-crossing position and the optimal wire re-crossing position during a bifurcation stenting, we developed the instant stent-accentuated three-dimensional optical coherence tomography (iSA 3D-OCT) system based on a novel algorithm. Stent struts in two-dimensional optical coherence tomography (2D-OCT) are represented as high-intensity line segments or spots in low-intensity background. Stent struts disappear and a vessel image is created by the mean filter followed by the minimum filter. A strut image is created by subtracting a vessel image from an original image, and accentuated. By adding a vessel image to a strut image, iSA 2D-OCT is created. It took only 3 s to accentuate stent struts of 100 frames by ImageJ with its macro program. By the iSA 3D-OCT system which consists of the console of OCT, the USB selector, USB cables, the USB flash drive, the computer, and three freeware programs, it took about 65 s from an export of the image data to an observation of iSA 3D-OCT semi-automatically. During a bifurcation stenting procedure, we could confirm the relation between stent struts and the jailed SB, the actual wire re-crossing position and the optimal wire re-crossing position. Using the iSA 3D-OCT system, a detailed process during a bifurcation PCI can be observed in very short waiting time, about 65 s. It is expected to improve the outcome of a complicated bifurcation PCI by the iSA 3D-OCT system.

  7. Surface area and volume measurements of volcanic ash particles using micro-computed tomography (micro-CT): A comparison with scanning electron microscope (SEM) stereoscopic imaging and geometric considerations

    NASA Astrophysics Data System (ADS)

    Ersoy, Orkun; Şen, Erdal; Aydar, Erkan; Tatar, İlkan; Çelik, H. Hamdi

    2010-10-01

    Volcanic ash particles are important components of explosive eruptions, and their surface textures are the subject of intense research. Characterization of ash surfaces is crucial for understanding the physics of volcanic plumes, remote sensing measurements of ash and aerosols, interfacial processes, modelling transportation and deposition of tephra and characterizing eruptive styles. A number of different methods have been used over the years to arrive at surface area estimates. The more common methods include estimates based on geometric considerations (geometric surface area) and physisorption of gas molecules on the surface of interest (physical surface area). In this study, micro computed tomography (micro-CT), which is a non-destructive method providing three-dimensional data, enabled the measurement of surface area and volume of individual ash particles. Results were compared with the values obtained from SEM stereoscopic imaging and geometric considerations. Surface area estimates of micro-CT and SEM stereoscopic imaging are similar, with surface area/volume ratios (SA/V) of 0.0368 and 0.0467, respectively. Ash particle surface textures show a large deviation from that of simple geometric forms, and an approximation both to spheres and ellipsoids do not seem adequate for the representation of ash surface. SEM stereoscopic and/or micro-CT imaging are here suggested as good candidate techniques for the characterization of textures on macro-pore regions of ash particles.

  8. Stereoscopic Flat Panel Display

    DTIC Science & Technology

    2004-12-01

    the display of stereo imagery have been demonstrated. Stereoscopic displays typically require the user to wear special headgear. Autostereoscopic ...components and the resulting changes in the encoding algorithm. Keywords: Stereoscopic display, LCD, 3D , polarization encoding, flat panel 1...panel display when viewing non-stereoscopic imagery or data. Remotely operated vehicles do not represent the only potential application for 3D

  9. Stereoscopic augmented reality for laparoscopic surgery.

    PubMed

    Kang, Xin; Azizian, Mahdi; Wilson, Emmanuel; Wu, Kyle; Martin, Aaron D; Kane, Timothy D; Peters, Craig A; Cleary, Kevin; Shekhar, Raj

    2014-07-01

    Conventional laparoscopes provide a flat representation of the three-dimensional (3D) operating field and are incapable of visualizing internal structures located beneath visible organ surfaces. Computed tomography (CT) and magnetic resonance (MR) images are difficult to fuse in real time with laparoscopic views due to the deformable nature of soft-tissue organs. Utilizing emerging camera technology, we have developed a real-time stereoscopic augmented-reality (AR) system for laparoscopic surgery by merging live laparoscopic ultrasound (LUS) with stereoscopic video. The system creates two new visual cues: (1) perception of true depth with improved understanding of 3D spatial relationships among anatomical structures, and (2) visualization of critical internal structures along with a more comprehensive visualization of the operating field. The stereoscopic AR system has been designed for near-term clinical translation with seamless integration into the existing surgical workflow. It is composed of a stereoscopic vision system, a LUS system, and an optical tracker. Specialized software processes streams of imaging data from the tracked devices and registers those in real time. The resulting two ultrasound-augmented video streams (one for the left and one for the right eye) give a live stereoscopic AR view of the operating field. The team conducted a series of stereoscopic AR interrogations of the liver, gallbladder, biliary tree, and kidneys in two swine. The preclinical studies demonstrated the feasibility of the stereoscopic AR system during in vivo procedures. Major internal structures could be easily identified. The system exhibited unobservable latency with acceptable image-to-video registration accuracy. We presented the first in vivo use of a complete system with stereoscopic AR visualization capability. This new capability introduces new visual cues and enhances visualization of the surgical anatomy. The system shows promise to improve the precision and

  10. Surface area and volume measurements of volcanic ash particles using micro-computed tomography (micro-CT): A comparison with scanning electron microscope (SEM) stereoscopic imaging and Brunauer-Emmett-Teller (BET) model

    NASA Astrophysics Data System (ADS)

    Ersoy, Orkun; Şen, Erdal; Aydar, Erkan; Tatar, Ä.°Lkan; Ćelik, H. Hamdi

    2010-05-01

    Volcanic ash particles are important components of explosive eruptions and their surface texture is the subject of intense research. Characterization of ash surfaces is crucial for understanding the physics of the volcanic plumes, remote sensing measurements of ash and aerosols, interfacial processes, modelling transportation and deposition of tephra and characterizing eruptive styles. A number of different methods have been used over the years to arrive at surface area estimates. The more common methods include estimates based on the geometric considerations (geometric surface area) and the physisorption of gas molecules on the surface of interest (physical surface area). In this study, micro computed tomography (micro-CT), a non-destructive method providing three-dimensional data enabled the measurement of surface areas and volumes of individual ash particles. Specific surface area estimates for ash particles were also obtained using nitrogen as gas adsorbent and the BET (Brunauer-Emmett-Teller) model. Results were compared with the values obtained from SEM stereoscopic imaging and geometric considerations. Surface area estimates of micro-CT and SEM stereoscopic imaging overlaps with mean specific surface area results of 0.0167 and 0.0214 m2/g, respectively. However, ash particle surface textures present quite a deviation from that of their geometric forms and approximation to sphere and ellipsoid both seemed to be inadequate for representation of real ash surfaces. The higher surface area estimate (> 0.4 m2/g) obtained from the technique based on physical sorption of gases (BET model here) was attributed to its capability for surface areas associated even with angstrom-sized pores. SEM stereoscopic and/or micro-CT imaging were suggested for characterization of textures on macro-pore regions of ash particles.

  11. Jig For Stereoscopic Photography

    NASA Technical Reports Server (NTRS)

    Nielsen, David J.

    1990-01-01

    Separations between views adjusted precisely for best results. Simple jig adjusted to set precisely, distance between right and left positions of camera used to make stereoscopic photographs. Camera slides in slot between extreme positions, where it takes stereoscopic pictures. Distance between extreme positions set reproducibly with micrometer. In view of trend toward very-large-scale integration of electronic circuits, training method and jig used to make training photographs useful to many companies to reduce cost of training manufacturing personnel.

  12. Stereoscopic camera design

    NASA Astrophysics Data System (ADS)

    Montgomery, David J.; Jones, Christopher K.; Stewart, James N.; Smith, Alan

    2002-05-01

    It is clear from the literature that the majority of work in stereoscopic imaging is directed towards the development of modern stereoscopic displays. As costs come down, wider public interest in this technology is expected to increase. This new technology would require new methods of image formation. Advances in stereo computer graphics will of course lead to the creation of new stereo computer games, graphics in films etc. However, the consumer would also like to see real-world stereoscopic images, pictures of family, holiday snaps etc. Such scenery would have wide ranges of depth to accommodate and would need also to cope with moving objects, such as cars, and in particular other people. Thus, the consumer acceptance of auto/stereoscopic displays and 3D in general would be greatly enhanced by the existence of a quality stereoscopic camera. This paper will cover an analysis of existing stereoscopic camera designs and show that they can be categorized into four different types, with inherent advantages and disadvantages. A recommendation is then made with regard to 3D consumer still and video photography. The paper will go on to discuss this recommendation and describe its advantages and how it can be realized in practice.

  13. [Measuring the instant].

    PubMed

    Cugini, P

    The instant is the infinitesimal fraction of time nearest to zero. Its computational measurement is not feasable in that it should be an infinitesimal commensurable portion of infinite time, which is incommensurabile by principle. The philosophical implication is that the instant has to be intended as an abstract entity belonging to metaphysical, transcendent, supranormal, suprasensitive, infinite time. In other words, the instant does not represent an experential deduction of our intellect, but an aprioristic innate idea letting us to be aware of physical, immanent, natural, sensible, finite temporality.

  14. Instant nonthermal leptogenesis

    SciTech Connect

    Ahn, Eun-Joo; Kolb, Edward W.; /Fermilab /Chicago U., Astron. Astrophys. Ctr. /Chicago U., EFI

    2005-08-01

    We propose an economical model of nonthermal leptogenesis following inflation during 'instant' preheating. The model involves only the inflaton field, the standard model Higgs, and the heavy 'right-handed' neutrino.

  15. Instant Childhood Immunization Schedule

    MedlinePlus

    ... Recommendations Why Immunize? Vaccines: The Basics Instant Childhood Immunization Schedule Recommend on Facebook Tweet Share Compartir Get ... date. See Disclaimer for additional details. Based on Immunization Schedule for Children 0 through 6 Years of ...

  16. Instant Messaging by SIP

    NASA Astrophysics Data System (ADS)

    Muhi, Daniel; Dulai, Tibor; Jaskó, Szilárd

    2008-11-01

    SIP is a general-purpose application layer protocol which is able to establish sessions between two or more parties. These sessions are mainly telephone calls and multimedia conferences. However it can be used for other purposes like instant messaging and presence service. SIP has a very important role in mobile communication as more and more communicating applications are going mobile. In this paper we would like to show how SIP can be used for instant messaging purposes.

  17. Nonpowered Instant Water Heater

    DTIC Science & Technology

    1994-08-01

    TECHNICAL REPORT AD NATICK/TR-94/028 __ NONPOWERED INSTANT WATER HEATER 00= By Eric C. Guyer Yankee Scientific, Inc. Medfield, MA 02052 August 1994...Instant water Heater Contract _ _._AUTHOR(S)_DAAK60-93-C-0022 6. AUTHOR(S) Eric C. Guyer 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) B. PERFORMING...DISTRIBUTION/AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE Approved for Public Release; Distribution Unlinited 13. ABSTRACT (Maximum 200 words ) The

  18. Stereoscopic image recoloring

    NASA Astrophysics Data System (ADS)

    Li, Xujie; Zhao, Hanli; Huang, Hui; Xiao, Lei; Hu, Zhongyi; Shao, Jingkai

    2016-09-01

    Image recoloring is the process of modification and adjustment of color appearance in images. Existing methods address the recoloring of a single image. We propose a method for recoloring stereoscopic images. Naively recoloring each image independently will require a pair of strokes in the source stereoscopic image pair. However, it is difficult to require consistent strokes on both the left and right views. We show how to extend a single image recoloring to work on stereoscopic images. Our method requires only a few user strokes on the left view and automatically transfers the corresponding strokes to the right view. Then a nonlocal color linear model optimization assumption is designed. Our nonlocal color linear model inherits the advantages of global and local color propagation methods. Our approach can propagate color cues in a global manner which can propagate color relatively far from the provided color constraints, while it provides the user with good local control. The experimental results show that the recolorized image pair is geometrically consistent with the original one.

  19. Instant Insanity II

    ERIC Educational Resources Information Center

    Richmond, Tom; Young, Aaron

    2013-01-01

    "Instant Insanity II" is a sliding mechanical puzzle whose solution requires the special alignment of 16 colored tiles. We count the number of solutions of the puzzle's classic challenge and show that the more difficult ultimate challenge has, up to row permutation, exactly two solutions, and further show that no…

  20. Grounding in Instant Messaging

    ERIC Educational Resources Information Center

    Fox Tree, Jean E.; Mayer, Sarah A.; Betts, Teresa E.

    2011-01-01

    In two experiments, we investigated predictions of the "collaborative theory of language use" (Clark, 1996) as applied to instant messaging (IM). This theory describes how the presence and absence of different grounding constraints causes people to interact differently across different communicative media (Clark & Brennan, 1991). In Study 1, we…

  1. Grounding in Instant Messaging

    ERIC Educational Resources Information Center

    Fox Tree, Jean E.; Mayer, Sarah A.; Betts, Teresa E.

    2011-01-01

    In two experiments, we investigated predictions of the "collaborative theory of language use" (Clark, 1996) as applied to instant messaging (IM). This theory describes how the presence and absence of different grounding constraints causes people to interact differently across different communicative media (Clark & Brennan, 1991). In Study 1, we…

  2. Are Instant Messages Speech?

    NASA Astrophysics Data System (ADS)

    Baron, Naomi S.

    Instant messaging (IM) is commonly viewed as a “spoken” medium, in light of its reputation for informality, non-standard spelling and punctuation, and use of lexical shortenings and emoticons. However, the actual nature of IM is an empirical issue that bears linguistic analysis.

  3. Instant Insanity II

    ERIC Educational Resources Information Center

    Richmond, Tom; Young, Aaron

    2013-01-01

    "Instant Insanity II" is a sliding mechanical puzzle whose solution requires the special alignment of 16 colored tiles. We count the number of solutions of the puzzle's classic challenge and show that the more difficult ultimate challenge has, up to row permutation, exactly two solutions, and further show that no…

  4. Universal electronic stereoscopic display

    NASA Astrophysics Data System (ADS)

    Lipton, Lenny; Halnon, Jeff

    1996-04-01

    SimulEYES VRTM, a new product for mass consumer electro-stereoscopic displays, is described. The system uses a unique indexing approach to allow content providers latitude in choosing the display mode. Board and PC manufacturers may also take advantage of the elegance of the solution by building in the SimulEYES VR capability. Hardware components consist, in part, of two custom chips which may be integrated at the board level, or employed in a VGA port dongle and control box. The liquid crystal shuttering eyewear is of a unique ergonomic design which is comfortable for people of all ages and most facial types, even when wearing eyeglasses.

  5. SU-E-J-39: Comparison of PTV Margins Determined by In-Room Stereoscopic Image Guidance and by On-Board Cone Beam Computed Tomography Technique for Brain Radiotherapy Patients

    SciTech Connect

    Ganesh, T; Paul, S; Munshi, A; Sarkar, B; Krishnankutty, S; Sathya, J; George, S; Jassal, K; Roy, S; Mohanti, B

    2014-06-01

    Purpose: Stereoscopic in room kV image guidance is a faster tool in daily monitoring of patient positioning. Our centre, for the first time in the world, has integrated such a solution from BrainLAB (ExacTrac) with Elekta's volumetric cone beam computed tomography (XVI). Using van Herk's formula, we compared the planning target volume (PTV) margins calculated by both these systems for patients treated with brain radiotherapy. Methods: For a total of 24 patients who received partial or whole brain radiotherapy, verification images were acquired for 524 treatment sessions by XVI and for 334 sessions by ExacTrac out of the total 547 sessions. Systematic and random errors were calculated in cranio-caudal, lateral and antero-posterior directions for both techniques. PTV margins were then determined using van Herk formula. Results: In the cranio-caudal direction, systematic error, random error and the calculated PTV margin were found to be 0.13 cm, 0.12 cm and 0.41 cm with XVI and 0.14 cm, 0.13 cm and 0.44 cm with ExacTrac. The corresponding values in lateral direction were 0.13 cm 0.1 cm and 0.4 cm with XVI and 0.13 cm, 0.12 cm and 0.42 cm with ExacTrac imaging. The same parameters for antero-posterior were for 0.1 cm, 0.11 cm and 0.34 cm with XVI and 0.13 cm, 0.16 cm and 0.43 cm with ExacTrac imaging. The margins estimated with the two imaging modalities were comparable within ± 1 mm limit. Conclusion: Verification of setup errors in the major axes by two independent imaging systems showed the results are comparable and within ± 1 mm. This implies that planar imaging based ExacTrac can yield equal accuracy in setup error determination as the time consuming volumetric imaging which is considered as the gold standard. Accordingly PTV margins estimated by this faster imaging technique can be confidently used in clinical setup.

  6. Stereoscopic optical viewing system

    DOEpatents

    Tallman, C.S.

    1986-05-02

    An improved optical system which provides the operator with a stereoscopic viewing field and depth of vision, particularly suitable for use in various machines such as electron or laser beam welding and drilling machines. The system features two separate but independently controlled optical viewing assemblies from the eyepiece to a spot directly above the working surface. Each optical assembly comprises a combination of eye pieces, turning prisms, telephoto lenses for providing magnification, achromatic imaging relay lenses and final stage pentagonal turning prisms. Adjustment for variations in distance from the turning prisms to the workpiece, necessitated by varying part sizes and configurations and by the operator's visual accuity, is provided separately for each optical assembly by means of separate manual controls at the operator console or within easy reach of the operator.

  7. Stereoscopic optical viewing system

    DOEpatents

    Tallman, Clifford S.

    1987-01-01

    An improved optical system which provides the operator a stereoscopic viewing field and depth of vision, particularly suitable for use in various machines such as electron or laser beam welding and drilling machines. The system features two separate but independently controlled optical viewing assemblies from the eyepiece to a spot directly above the working surface. Each optical assembly comprises a combination of eye pieces, turning prisms, telephoto lenses for providing magnification, achromatic imaging relay lenses and final stage pentagonal turning prisms. Adjustment for variations in distance from the turning prisms to the workpiece, necessitated by varying part sizes and configurations and by the operator's visual accuity, is provided separately for each optical assembly by means of separate manual controls at the operator console or within easy reach of the operator.

  8. A novel 3D stereoscopic anatomy tutorial.

    PubMed

    Brown, Philip M; Hamilton, Neil M; Denison, Alan R

    2012-02-01

    Advancement in technology is an important driver for the evolution of the medical curriculum. With continued criticism of medical students' knowledge of anatomy, further investigation into adjuncts for anatomy teaching seems appropriate. This project sought to create an interactive 3D stereoscopic tutorial to bridge the teaching of anatomy and pathology. Anonymised computed tomography (CT) scans were collected of a normal aorta and a ruptured abdominal aortic aneurysm. These scans were rendered into 3D stereoscopic images using open-source software. These images were then annotated with interactive labels and buttons to access information on normal aortic anatomy and the clinical details of abdominal aortic aneurysms. A total of 183 first-year medical students viewed the tutorial, and 160 gave feedback (87%). The students found the 3D system aided their understanding of anatomy and pathology (93 versus 3%), and provided an advantage when compared with current anatomy classes (93 versus 1%). The students highlighted the musculoskeletal system and cerebral vasculature as areas for future 3D visualisation. Of the responders, 96 per cent felt that the curriculum would benefit from further 3D stereoscopic anatomy/pathology tutorials. This technology has the exciting potential to use the radiographic libraries in hospitals for medical education. The computer software, however, has some limitations at present. It is not able to effectively distinguish between tissues of similar densities. Furthermore, not all tissues are amenable to CT scanning of a high enough resolution for presentation. Despite these limitations, the software continues to advance and is capable of producing very high quality anatomy images. © Blackwell Publishing Ltd 2012.

  9. [Dendrobium officinale stereoscopic cultivation method].

    PubMed

    Si, Jin-Ping; Dong, Hong-Xiu; Liao, Xin-Yan; Zhu, Yu-Qiu; Li, Hui

    2014-12-01

    The study is aimed to make the most of available space of Dendrobium officinale cultivation facility, reveal the yield and functional components variation of stereoscopic cultivated D. officinale, and improve quality, yield and efficiency. The agronomic traits and yield variation of stereoscopic cultivated D. officinale were studied by operating field experiment. The content of polysaccharide and extractum were determined by using phenol-sulfuric acid method and 2010 edition of "Chinese Pharmacopoeia" Appendix X A. The results showed that the land utilization of stereoscopic cultivated D. officinale increased 2.74 times, the stems, leaves and their total fresh or dry weight in unit area of stereoscopic cultivated D. officinale were all heavier than those of the ground cultivated ones. There was no significant difference in polysaccharide content between stereoscopic cultivation and ground cultivation. But the extractum content and total content of polysaccharide and extractum were significantly higher than those of the ground cultivated ones. In additional, the polysaccharide content and total content of polysaccharide and extractum from the top two levels of stereoscopic culture matrix were significantly higher than that of the ones from the other levels and ground cultivation. Steroscopic cultivation can effectively improves the utilization of space and yield, while the total content of polysaccharides and extractum were significantly higher than that of the ground cultivated ones. The significant difference in Dendrobium polysaccharides among the plants from different height of stereo- scopic culture matrix may be associated with light factor.

  10. Stereoscopically Observing Manipulative Actions

    PubMed Central

    Ferri, S.; Pauwels, K.; Rizzolatti, G.; Orban, G. A.

    2016-01-01

    The purpose of this study was to investigate the contribution of stereopsis to the processing of observed manipulative actions. To this end, we first combined the factors “stimulus type” (action, static control, and dynamic control), “stereopsis” (present, absent) and “viewpoint” (frontal, lateral) into a single design. Four sites in premotor, retro-insular (2) and parietal cortex operated specifically when actions were viewed stereoscopically and frontally. A second experiment clarified that the stereo-action-specific regions were driven by actions moving out of the frontoparallel plane, an effect amplified by frontal viewing in premotor cortex. Analysis of single voxels and their discriminatory power showed that the representation of action in the stereo-action-specific areas was more accurate when stereopsis was active. Further analyses showed that the 4 stereo-action-specific sites form a closed network converging onto the premotor node, which connects to parietal and occipitotemporal regions outside the network. Several of the specific sites are known to process vestibular signals, suggesting that the network combines observed actions in peripersonal space with gravitational signals. These findings have wider implications for the function of premotor cortex and the role of stereopsis in human behavior. PMID:27252350

  11. Saliency detection for stereoscopic images.

    PubMed

    Fang, Yuming; Wang, Junle; Narwaria, Manish; Le Callet, Patrick; Lin, Weisi

    2014-06-01

    Many saliency detection models for 2D images have been proposed for various multimedia processing applications during the past decades. Currently, the emerging applications of stereoscopic display require new saliency detection models for salient region extraction. Different from saliency detection for 2D images, the depth feature has to be taken into account in saliency detection for stereoscopic images. In this paper, we propose a novel stereoscopic saliency detection framework based on the feature contrast of color, luminance, texture, and depth. Four types of features, namely color, luminance, texture, and depth, are extracted from discrete cosine transform coefficients for feature contrast calculation. A Gaussian model of the spatial distance between image patches is adopted for consideration of local and global contrast calculation. Then, a new fusion method is designed to combine the feature maps to obtain the final saliency map for stereoscopic images. In addition, we adopt the center bias factor and human visual acuity, the important characteristics of the human visual system, to enhance the final saliency map for stereoscopic images. Experimental results on eye tracking databases show the superior performance of the proposed model over other existing methods.

  12. Venus - Stereoscopic Images of Volcanic Domes

    NASA Image and Video Library

    1996-03-14

    This Magellan image depicts a stereoscopic pair of an area on Venus with small volcanic domes. Stereoscopic images of Venus offer exciting new possibilities for scientific analysis of Venusian landforms. http://photojournal.jpl.nasa.gov/catalog/PIA00251

  13. Techniques for Fast Stereoscopic MRI

    PubMed Central

    Guttman, Michael A.; McVeigh, Elliot R.

    2007-01-01

    Stereoscopic MRI can impart 3D perception with only two image acquisitions. This economy over standard multiplanar 3D volume renderings allows faster frame rates, which are needed for real-time imaging applications. Real-time 3D perception may enhance the appreciation of complex anatomical structures, and may improve hand-eye coordination while manipulating a medical device during an image-guided interventional procedure. To this goal, a system is being developed to acquire and display stereoscopic MR images in real-time. A clinically used, fast gradient-recalled echo-train sequence has been modified to produce stereo image pairs. Features have been added for depth cueing, view sharing, and bulk signal suppression. A workstation was attached to a clinical MR scanner for fast data extraction, image reconstruction and stereoscopic image display. PMID:11477636

  14. Stereoscopic applications for design visualization

    NASA Astrophysics Data System (ADS)

    Gilson, Kevin J.

    2007-02-01

    Advances in display technology and 3D design visualization applications have made real-time stereoscopic visualization of architectural and engineering projects a reality. Parsons Brinkerhoff (PB) is a transportation consulting firm that has used digital visualization tools from their inception and has helped pioneer the application of those tools to large scale infrastructure projects. PB is one of the first Architecture/Engineering/Construction (AEC) firms to implement a CAVE- an immersive presentation environment that includes stereoscopic rear-projection capability. The firm also employs a portable stereoscopic front-projection system, and shutter-glass systems for smaller groups. PB is using commercial real-time 3D applications in combination with traditional 3D modeling programs to visualize and present large AEC projects to planners, clients and decision makers in stereo. These presentations create more immersive and spatially realistic presentations of the proposed designs. This paper will present the basic display tools and applications, and the 3D modeling techniques PB is using to produce interactive stereoscopic content. The paper will discuss several architectural and engineering design visualizations we have produced.

  15. Ghosting in anaglyphic stereoscopic images

    NASA Astrophysics Data System (ADS)

    Woods, Andrew J.; Rourke, Tegan

    2004-05-01

    Anaglyphic 3D images are an easy way of displaying stereoscopic 3D images on a wide range of display types, e.g. CRT, LCD, print, etc. While the anaglyphic 3D image method is cheap and accessible, its use requires a compromise in stereoscopic image quality. A common problem with anaglyphic 3D images is ghosting. Ghosting (or crosstalk) is the leaking of an image to one eye, when it is intended exclusively for the other eye. Ghosting degrades the ability of the observer to fuse the stereoscopic image and hence the quality of the 3D image is reduced. Ghosting is present in various levels with most stereoscopic displays, however it is often particularly evident with anaglyphic 3D images. This paper describes a project whose aim was to characterize the presence of ghosting in anaglyphic 3D images due to spectral issues. The spectral response curves of several different display types and several different brands of anaglyph glasses were measured using a spectroradiometer or spectrophotometer. A mathematical model was then developed to predict the amount of crosstalk in anaglyphic 3D images when different combinations of displays and glasses are used, and therefore predict the best type of anaglyph glasses for use with a particular display type.

  16. A rendering approach for stereoscopic web pages

    NASA Astrophysics Data System (ADS)

    Zhang, Jianlong; Wang, Wenmin; Wang, Ronggang; Chen, Qinshui

    2014-03-01

    Web technology provides a relatively easy way to generate contents for us to recognize the world, and with the development of stereoscopic display technology, the stereoscopic devices will become much more popular. The combination of web technology and stereoscopic display technology will bring revolutionary visual effect. The Stereoscopic 3D (S3D) web pages, in which text, image and video may have different depth, can be displayed on stereoscopic display devices. This paper presents the approach about how to render two viewing S3D web pages including text, images, widgets: first, an algorithm should be developed in order to display stereoscopic elements like text, widgets by using 2D graphic library; second, a method should be presented to render stereoscopic web page based on current framework of the browser; third, a rough solution is invented to fix the problem that comes out in the method.

  17. 21 CFR 137.170 - Instantized flours.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Instantized flours. 137.170 Section 137.170 Food... HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.170 Instantized flours. (a) Instantized flours, instant blending...

  18. 21 CFR 137.170 - Instantized flours.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Instantized flours. 137.170 Section 137.170 Food... HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.170 Instantized flours. (a) Instantized flours, instant blending...

  19. 21 CFR 137.170 - Instantized flours.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Instantized flours. 137.170 Section 137.170 Food... HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.170 Instantized flours. (a) Instantized flours, instant blending...

  20. Stereoscopic observations from meteorological satellites

    NASA Astrophysics Data System (ADS)

    Hasler, A. F.; Mack, R.; Negri, A.

    The capability of making stereoscopic observations of clouds from meteorological satellites is a new basic analysis tool with a broad spectrum of applications. Stereoscopic observations from satellites were first made using the early vidicon tube weather satellites (e.g., Ondrejka and Conover [1]). However, the only high quality meteorological stereoscopy from low orbit has been done from Apollo and Skylab, (e.g., Shenk et al. [2] and Black [3], [4]). Stereoscopy from geosynchronous satellites was proposed by Shenk [5] and Bristor and Pichel [6] in 1974 which allowed Minzner et al. [7] to demonstrate the first quantitative cloud height analysis. In 1978 Bryson [8] and desJardins [9] independently developed digital processing techniques to remap stereo images which made possible precision height measurement and spectacular display of stereograms (Hasler et al. [10], and Hasler [11]). In 1980 the Japanese Geosynchronous Satellite (GMS) and the U.S. GOES-West satellite were synchronized to obtain stereo over the central Pacific as described by Fujita and Dodge [12] and in this paper. Recently the authors have remapped images from a Low Earth Orbiter (LEO) to the coordinate system of a Geosynchronous Earth Orbiter (GEO) and obtained stereoscopic cloud height measurements which promise to have quality comparable to previous all GEO stereo. It has also been determined that the north-south imaging scan rate of some GEOs can be slowed or reversed. Therefore the feasibility of obtaining stereoscopic observations world wide from combinations of operational GEO and LEO satellites has been demonstrated. Stereoscopy from satellites has many advantages over infrared techniques for the observation of cloud structure because it depends only on basic geometric relationships. Digital remapping of GEO and LEO satellite images is imperative for precision stereo height measurement and high quality displays because of the curvature of the earth and the large angular separation of the

  1. Stereoscopic medical imaging collaboration system

    NASA Astrophysics Data System (ADS)

    Okuyama, Fumio; Hirano, Takenori; Nakabayasi, Yuusuke; Minoura, Hirohito; Tsuruoka, Shinji

    2007-02-01

    The computerization of the clinical record and the realization of the multimedia have brought improvement of the medical service in medical facilities. It is very important for the patients to obtain comprehensible informed consent. Therefore, the doctor should plainly explain the purpose and the content of the diagnoses and treatments for the patient. We propose and design a Telemedicine Imaging Collaboration System which presents a three dimensional medical image as X-ray CT, MRI with stereoscopic image by using virtual common information space and operating the image from a remote location. This system is composed of two personal computers, two 15 inches stereoscopic parallax barrier type LCD display (LL-151D, Sharp), one 1Gbps router and 1000base LAN cables. The software is composed of a DICOM format data transfer program, an operation program of the images, the communication program between two personal computers and a real time rendering program. Two identical images of 512×768 pixcels are displayed on two stereoscopic LCD display, and both images show an expansion, reduction by mouse operation. This system can offer a comprehensible three-dimensional image of the diseased part. Therefore, the doctor and the patient can easily understand it, depending on their needs.

  2. A stereoscopic lens for digital cinema cameras

    NASA Astrophysics Data System (ADS)

    Lipton, Lenny; Rupkalvis, John

    2015-03-01

    Live-action stereoscopic feature films are, for the most part, produced using a costly post-production process to convert planar cinematography into stereo-pair images and are only occasionally shot stereoscopically using bulky dual-cameras that are adaptations of the Ramsdell rig. The stereoscopic lens design described here might very well encourage more live-action image capture because it uses standard digital cinema cameras and workflow to save time and money.

  3. Novel 3D stereoscopic imaging technology

    NASA Astrophysics Data System (ADS)

    Faris, Sadeg M.

    1994-04-01

    Numerous 3-D stereoscopic techniques have been explored. These previous techniques have had shortcomings precluding them from making stereoscopic imaging pervasive in mainstream applications. In the last decade, several enabling technologies have emerged and have become available and affordable. They make it possible now to realize the near-ideal stereoscopic imaging technology that can be made available to the masses making possible the inevitable transition from flat imaging to stereoscopic imaging. The ideal stereoscopic technology must meet four important criteria: (1) high stereoscopic image quality; (2) affordability; (3) compatibility with existing infrastructure, e.g., NTSC video, PC, and other devices; and (4) general purpose characteristics, e.g., the ability to produce electronic displays, hard-copy printing and capturing stereoscopic images on film and stored electronically. In section 2, an overview of prior art technologies is given highlighting their advantages and disadvantages. In section 3, the novel (mu) PolTM stereoscopic technology is described making the case that it meets the four criteria for realizing the inevitable transition from flat to stereoscopic imaging for mass applications.

  4. Assessing Spatial Cognition in Stereoscopic Environments

    NASA Astrophysics Data System (ADS)

    Price, Aaron; Lee, H.

    2008-05-01

    Nineteen middle-school aged students visiting a planetarium were presented with three visuospatial tasks in both 2D (paper) and stereoscopic environments. The students' performance on tasks was evaluated in order to determine the impact of stereoscopic presentation upon accuracy and task completion time. Results show that accuracy did not differ between the two representational environments while completion time was greater for the stereoscopic environment. Post task interviews show that spatial and temporal discontiguity increased the cognitive load. Additionally, the interviews showed that students continued to visualize in two dimensions while using the stereoscopic representations.

  5. Stereoscopic game design and evaluation

    NASA Astrophysics Data System (ADS)

    Rivett, Joe; Holliman, Nicolas

    2013-03-01

    We report on a new game design where the goal is to make the stereoscopic depth cue sufficiently critical to success that game play should become impossible without using a stereoscopic 3D (S3D) display and, at the same time, we investigate whether S3D game play is affected by screen size. Before we detail our new game design we review previously unreported results from our stereoscopic game research over the last ten years at the Durham Visualisation Laboratory. This demonstrates that game players can achieve significantly higher scores using S3D displays when depth judgements are an integral part of the game. Method: We design a game where almost all depth cues, apart from the binocular cue, are removed. The aim of the game is to steer a spaceship through a series of oncoming hoops where the viewpoint of the game player is from above, with the hoops moving right to left across the screen towards the spaceship, to play the game it is essential to make decisive depth judgments to steer the spaceship through each oncoming hoop. To confound these judgements we design altered depth cues, for example perspective is reduced as a cue by varying the hoop's depth, radius and cross-sectional size. Results: Players were screened for stereoscopic vision, given a short practice session, and then played the game in both 2D and S3D modes on a seventeen inch desktop display, on average participants achieved a more than three times higher score in S3D than they achieved in 2D. The same experiment was repeated using a four metre S3D projection screen and similar results were found. Conclusions: Our conclusion is that games that use the binocular depth cue in decisive game judgements can benefit significantly from using an S3D display. Based on both our current and previous results we additionally conclude that display size, from cell-phone, to desktop, to projection display does not adversely affect player performance.

  6. Outcome Evaluation of the Instant Word Notebook

    ERIC Educational Resources Information Center

    Bland, Adrienne Lynn

    2012-01-01

    The Instant Word Notebook study was a program evaluation completed by two educators who saw a need for an instructional tool to teach and assess Instant Words. In order to address reading deficits of students in first and second grades, teachers were expected to teach Instant Words. Unfortunately, teachers did not have a systematic process to…

  7. Outcome Evaluation of the Instant Word Notebook

    ERIC Educational Resources Information Center

    Bland, Adrienne Lynn

    2012-01-01

    The Instant Word Notebook study was a program evaluation completed by two educators who saw a need for an instructional tool to teach and assess Instant Words. In order to address reading deficits of students in first and second grades, teachers were expected to teach Instant Words. Unfortunately, teachers did not have a systematic process to…

  8. Instant Pudding and Pie Filling

    DTIC Science & Technology

    1980-04-01

    0.57 Cocoa 12.46 Chocolate flavor enhancer 0.04 Artificial vanilla flavor 0.10 4 Food starch-modified, pre-gelatinized 14.32 Powdered vegetable... chocolate , vanilla and butterscotch flavors - were developed by NARADCOM, successfully production-tested, and subsequently procured through...powder of Example 1. These were chilled, sliced and served in the same manner as in Example 1. 8 Example 3 A chocolate flavored instant dessert

  9. Depth Perception In Remote Stereoscopic Viewing Systems

    NASA Technical Reports Server (NTRS)

    Diner, Daniel B.; Von Sydow, Marika

    1989-01-01

    Report describes theoretical and experimental studies of perception of depth by human operators through stereoscopic video systems. Purpose of such studies to optimize dual-camera configurations used to view workspaces of remote manipulators at distances of 1 to 3 m from cameras. According to analysis, static stereoscopic depth distortion decreased, without decreasing stereoscopitc depth resolution, by increasing camera-to-object and intercamera distances and camera focal length. Further predicts dynamic stereoscopic depth distortion reduced by rotating cameras around center of circle passing through point of convergence of viewing axes and first nodal points of two camera lenses.

  10. Stereoscopic desktop VR system for telemaintenance

    NASA Astrophysics Data System (ADS)

    Kleiber, Michael; Weltjen, Bastian; Förster, Julia

    2012-03-01

    Tele-cooperation for maintenance is usually supported by synchronous audio but only asynchronous video exchange when only limited bandwidth is available. We present an alternative approach for such a collaborative maintenance task. By utilizing techniques and technologies from Augmented Reality (AR) applications our approach can provide a synchronous shared visual context for the collaborators without a direct video link but through a Desktop VR system. To increase the spatial presence of the remote expert we employ stereoscopic displays. The effectiveness of a stereoscopic 3D system for orientation and localization was evaluated in an abstract experiment. In a more practical experiment the stereoscopic VR system was also evaluated by automobile mechanics. The benefits of stereoscopic Desktop VR systems were shown in both experiments.

  11. Depth perception estimation of various stereoscopic displays.

    PubMed

    Baek, Sangwook; Lee, Chulhee

    2016-10-17

    In this paper, we investigate the relationship between depth perception and several disparity parameters in stereoscopic images. A number of subjective experiments were conducted using various 3D displays, which indicate that depth perception of stereoscopic images is proportional to depth difference and is inversely related to the camera distance. Based on this observation, we developed some formulas to quantify the degree of depth perception of stereoscopic images. The proposed method uses depth differences and the camera distance between the objects and the 3D camera. This method also produces improved depth perception estimation by using non-linear functions whose inputs include a depth difference and a camera distance. The results show that the proposed method provides noticeable improvements in terms of correlation and produces more accurate depth perception estimations of stereoscopic images.

  12. Birth in an Ordinary Instant

    PubMed Central

    De Vries, Charlotte

    2010-01-01

    Our daily lives are a series of ordinary moments and unnoticed thresholds—times that define us in ways we often do not give much attention. While we consider childbirth to be one of life's extra-ordinary events, the hours of labor and birth need not be dramatic (or traumatic) ones. I describe a quiet, well-supported birth in the Netherlands that is cause for celebration of the beauty of an ordinary instant that can define and enrich the human experience. PMID:21629383

  13. Industrial Application Of Instant Holography

    NASA Astrophysics Data System (ADS)

    Schorner, J.; Rottenkolber, H.

    1983-10-01

    The development of holographic test methods has lead to a wide industrial application. Today serial tests of aircraft tyres with holography have become routine. A large chemical company is testing their plastic materials like tanks, wheels and fans with the method of holographic interferometry. In the power engine industry turbine blades are tested holographically to find an optimal shape and to test the vibration behaviour. The automotive industry is using holographic methods' for construction optimization. The economic application of these test methods was possible by using instant holography. The principle of a new hologramrecorder is presented. The application of this equipment is shown in examples of testing materials, optimizing constructions and vibration analysis.

  14. Quantitative Evaluation of Papilledema from Stereoscopic Color Fundus Photographs

    PubMed Central

    Tang, Li; Kardon, Randy H.; Wang, Jui-Kai; Garvin, Mona K.; Lee, Kyungmoo; Abràmoff, Michael D.

    2012-01-01

    Purpose. To derive a computerized measurement of optic disc volume from digital stereoscopic fundus photographs for the purpose of diagnosing and managing papilledema. Methods. Twenty-nine pairs of stereoscopic fundus photographs and optic nerve head (ONH) centered spectral domain optical coherence tomography (SD-OCT) scans were obtained at the same visit in 15 patients with papilledema. Some patients were imaged at multiple visits in order to assess their changes. Three-dimensional shape of the ONH was estimated from stereo fundus photographs using an automated multi-scale stereo correspondence algorithm. We assessed the correlation of the stereo volume measurements with the SD-OCT volume measurements quantitatively, in terms of volume of retinal surface elevation above a reference plane and also to expert grading of papilledema from digital fundus photographs using the Frisén grading scale. Results. The volumetric measurements of retinal surface elevation estimated from stereo fundus photographs and OCT scans were positively correlated (correlation coefficient r2 = 0.60; P < 0.001) and were positively correlated with Frisén grade (Spearman correlation coefficient r = 0.59; P < 0.001). Conclusions. Retinal surface elevation among papilledema patients obtained from stereo fundus photographs compares favorably with that from OCT scans and with expert grading of papilledema severity. Stereoscopic color imaging of the ONH combined with a method of automated shape reconstruction is a low-cost alternative to SD-OCT scans that has potential for a more cost-effective diagnosis and management of papilledema in a telemedical setting. An automated three-dimensional image analysis method was validated that quantifies the retinal surface topography with an imaging modality that has lacked prior objective assessment. PMID:22661468

  15. Original and creative stereoscopic film making

    NASA Astrophysics Data System (ADS)

    Criado, Enrique

    2008-02-01

    The stereoscopic cinema has become, once again, a hot topic in the film production. For filmmakers to be successful in this field, a technical background in the principles of binocular perception and how our brain interprets the incoming data from our eyes, are fundamental. It is also paramount for a stereoscopic production to adhere certain rules for comfort and safety. There is an immense variety of options in the art of standard "flat" photography, and the possibilities only can be multiply with the stereo. The stereoscopic imaging has its own unique areas for subjective, original and creative control that allow an incredible range of possible combinations by working inside the standards, and in some cases on the boundaries of the basic stereo rules. The stereoscopic imaging can be approached in a "flat" manner, like channeling sound through an audio equalizer with all the bands at the same level. It can provide a realistic perception, which in many cases can be sufficient, thanks to the rock-solid viewing inherent to the stereoscopic image, but there are many more possibilities. This document describes some of the basic operating parameters and concepts for stereoscopic imaging, but it also offers ideas for a creative process based on the variation and combination of these basic parameters, which can lead into a truly innovative and original viewing experience.

  16. Motion in depth constancy in stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Laldin, Sidrah R.; Wilcox, Laurie M.; Hylton, Carly; Allison, Robert S.

    2012-03-01

    In a stereoscopic 3D scene, non-linear mapping between real space and disparity could produce distortions when camera geometry differs from natural stereoscopic geometry. When the viewing distance and zero screen parallax setting are held constant and interaxial separation is varied, there is an asymmetric distortion in the mapping of stereoscopic to real space. If an object traverses this space at constant velocity, one might anticipate distortion of the perceived velocity. To determine if the predicted distortions are in fact perceived, we assessed perceived acceleration and deceleration using an animation of a ball moving in depth through a simulated environment, viewed stereoscopically. The method of limits was used to measure transition points between perceived acceleration and deceleration as a function of interaxial and context (textured vs. non-textured background). Based on binocular geometry, we predicted that the transition points would shift toward deceleration for small and towards acceleration for large interaxial separations. However, the average transition values were not influenced by interaxial separation. These data suggest that observers are able to discount distortions of stereoscopic space in interpreting the object motion. These results have important implications for the rendering or capture of effective stereoscopic 3D content.

  17. Crosstalk in stereoscopic displays: a review

    NASA Astrophysics Data System (ADS)

    Woods, Andrew J.

    2012-10-01

    Crosstalk, also known as ghosting or leakage, is a primary factor in determining the image quality of stereoscopic three dimensional (3D) displays. In a stereoscopic display, a separate perspective view is presented to each of the observer's two eyes in order to experience a 3D image with depth sensation. When crosstalk is present in a stereoscopic display, each eye will see a combination of the image intended for that eye, and some of the image intended for the other eye-making the image look doubled or ghosted. High levels of crosstalk can make stereoscopic images hard to fuse and lack fidelity, so it is important to achieve low levels of crosstalk in the development of high-quality stereoscopic displays. Descriptive and mathematical definitions of these terms are formalized and summarized. The mechanisms by which crosstalk occurs in different stereoscopic display technologies are also reviewed, including micropol 3D liquid crystal displays (LCDs), autostereoscopic (lenticular and parallax barrier), polarized projection, anaglyph, and time-sequential 3D on LCDs, plasma display panels and cathode ray tubes. Crosstalk reduction and crosstalk cancellation are also discussed along with methods of measuring and simulating crosstalk.

  18. A novel stereoscopic projection display system for CT images of fractures.

    PubMed

    Liu, Xiujuan; Jiang, Hong; Lang, Yuedong; Wang, Hongbo; Sun, Na

    2013-06-01

    The present study proposed a novel projection display system based on a virtual reality enhancement environment. The proposed system displays stereoscopic images of fractures and enhances the computed tomography (CT) images. The diagnosis and treatment of fractures primarily depend on the post-processing of CT images. However, two-dimensional (2D) images do not show overlapping structures in fractures since they are displayed without visual depth and these structures are too small to be simultaneously observed by a group of clinicians. Stereoscopic displays may solve this problem and allow clinicians to obtain more information from CT images. Hardware with which to generate stereoscopic images was designed. This system utilized the conventional equipment found in meeting rooms. The off-axis algorithm was adopted to convert the CT images into stereo image pairs, which were used as the input for a stereo generator. The final stereoscopic images were displayed using a projection system. Several CT fracture images were imported into the system for comparison with traditional 2D CT images. The results showed that the proposed system aids clinicians in group discussions by producing large stereoscopic images. The results demonstrated that the enhanced stereoscopic CT images generated by the system appear clearer and smoother, such that the sizes, displacement and shapes of bone fragments are easier to assess. Certain fractures that were previously not visible on 2D CT images due to vision overlap became vividly evident in the stereo images. The proposed projection display system efficiently, economically and accurately displayed three-dimensional (3D) CT images. The system may help clinicians improve the diagnosis and treatment of fractures.

  19. A novel stereoscopic projection display system for CT images of fractures

    PubMed Central

    LIU, XIUJUAN; JIANG, HONG; LANG, YUEDONG; WANG, HONGBO; SUN, NA

    2013-01-01

    The present study proposed a novel projection display system based on a virtual reality enhancement environment. The proposed system displays stereoscopic images of fractures and enhances the computed tomography (CT) images. The diagnosis and treatment of fractures primarily depend on the post-processing of CT images. However, two-dimensional (2D) images do not show overlapping structures in fractures since they are displayed without visual depth and these structures are too small to be simultaneously observed by a group of clinicians. Stereoscopic displays may solve this problem and allow clinicians to obtain more information from CT images. Hardware with which to generate stereoscopic images was designed. This system utilized the conventional equipment found in meeting rooms. The off-axis algorithm was adopted to convert the CT images into stereo image pairs, which were used as the input for a stereo generator. The final stereoscopic images were displayed using a projection system. Several CT fracture images were imported into the system for comparison with traditional 2D CT images. The results showed that the proposed system aids clinicians in group discussions by producing large stereoscopic images. The results demonstrated that the enhanced stereoscopic CT images generated by the system appear clearer and smoother, such that the sizes, displacement and shapes of bone fragments are easier to assess. Certain fractures that were previously not visible on 2D CT images due to vision overlap became vividly evident in the stereo images. The proposed projection display system efficiently, economically and accurately displayed three-dimensional (3D) CT images. The system may help clinicians improve the diagnosis and treatment of fractures. PMID:23837053

  20. Should We Ban Instant Messaging In School?

    ERIC Educational Resources Information Center

    Texley, Sharon; DeGennaro, Donna

    2005-01-01

    This article is a brief debate on the pros and cons of allowing students to use instant messaging (IM) in school. On one hand, teenagers' desire to socialize can overcome other priorities and schools may set policies to ban instant messaging. The contrary view is that schools should embrace the IM technology being popularized by youth and find…

  1. Enhancing Students' Learning: Instant Feedback Cards

    ERIC Educational Resources Information Center

    Mohrweis, Lawrence C.; Shinham, Kathe M.

    2015-01-01

    This study illustrates an active learning approach using instant feedback cards in the first course in accounting. The objectives of this study are to (1) describe instant feedback cards and (2) show how this tool, when used in an active learning environment, can enhance learning. We examined whether students exposed to immediate feedback…

  2. Process Evaluation of the Instant Word Notebook

    ERIC Educational Resources Information Center

    Roberts, Jeannie Ellen

    2010-01-01

    This program evaluation of The Instant Word Notebook was conducted by two educators who created an instructional tool to teach and assess the most frequently occurring words in written text, commonly known as Instant Words. In an effort to increase the reading scores of first and second grade students, teachers were instructed to teach Instant…

  3. Process Evaluation of the Instant Word Notebook

    ERIC Educational Resources Information Center

    Roberts, Jeannie Ellen

    2010-01-01

    This program evaluation of The Instant Word Notebook was conducted by two educators who created an instructional tool to teach and assess the most frequently occurring words in written text, commonly known as Instant Words. In an effort to increase the reading scores of first and second grade students, teachers were instructed to teach Instant…

  4. Instant Messaging in Dental Education.

    PubMed

    Khatoon, Binish; Hill, Kirsty B; Walmsley, A Damien

    2015-12-01

    Instant messaging (IM) is when users communicate instantly via their mobile devices, and it has become one of the most preferred choices of tools to communicate amongst health professions students. The aim of this study was to understand how dental students communicate via IM, faculty members' perspectives on using IM to communicate with students, and whether such tools are useful in the learning environment. After free-associating themes on online communication, two draft topic guides for structured interviews were designed that focussed on mobile device-related communication activities. A total of 20 students and six faculty members at the University of Birmingham School of Dentistry agreed to take part in the interviews. Students were selected from years 1-5 representing each year group. The most preferred communication tools were emails, social networking, and IM. Emails were used for more formal messages, and IM and social networking sites were used for shorter messages. WhatsApp was the most used IM app because of its popular features such as being able to check if recipients have read and received messages and group work. The students reported that changes were necessary to improve their communication with faculty members. The faculty members reported having mixed feelings toward the use of IM to communicate with students. The students wished to make such tools a permanent part of their learning environment, but only with the approval of faculty members. The faculty members were willing to accept IM as a communication tool only if it is monitored and maintained by the university and has a positive effect on learning.

  5. Two Eyes, 3D: Stereoscopic Design Principles

    NASA Astrophysics Data System (ADS)

    Price, Aaron; Subbarao, M.; Wyatt, R.

    2013-01-01

    Two Eyes, 3D is a NSF-funded research project about how people perceive highly spatial objects when shown with 2D or stereoscopic ("3D") representations. As part of the project, we produced a short film about SN 2011fe. The high definition film has been rendered in both 2D and stereoscopic formats. It was developed according to a set of stereoscopic design principles we derived from the literature and past experience producing and studying stereoscopic films. Study participants take a pre- and post-test that involves a spatial cognition assessment and scientific knowledge questions about Type-1a supernovae. For the evaluation, participants use iPads in order to record spatial manipulation of the device and look for elements of embodied cognition. We will present early results and also describe the stereoscopic design principles and the rationale behind them. All of our content and software is available under open source licenses. More information is at www.twoeyes3d.org.

  6. Consciousness and stereoscopic environmental imaging

    NASA Astrophysics Data System (ADS)

    Mason, Steve

    2014-02-01

    The question of human consciousness has intrigued philosophers and scientists for centuries: its nature, how we perceive our environment, how we think, our very awareness of thought and self. It has been suggested that stereoscopic vision is "a paradigm of how the mind works" 1 In depth perception, laws of perspective are known, reasoned, committed to memory from an early age; stereopsis, on the other hand, is a 3D experience governed by strict laws but actively joined within the brain―one sees it without explanation. How do we, in fact, process two different images into one 3D module within the mind and does an awareness of this process give us insight into the workings of our own consciousness? To translate this idea to imaging I employed ChromaDepth™ 3D glasses that rely on light being refracted in a different direction for each eye―colors of differing wavelengths appearing at varying distances from the viewer resulting in a 3D space. This involves neither calculation nor manufacture of two images or views. Environmental spatial imaging was developed―a 3D image was generated that literally surrounds the viewer. The image was printed and adhered to a semi-circular mount; the viewer then entered the interior to experience colored shapes suspended in a 3D space with an apparent loss of surface, or picture plane, upon which the image is rendered. By focusing our awareness through perception-based imaging we are able to gain a deeper understanding of how the brain works, how we see.

  7. Shifting Of Image Fields For Better Stereoscopic TV Images

    NASA Technical Reports Server (NTRS)

    Diner, Daniel B.

    1988-01-01

    Concept for shifting horizontal positions of TV image fields of stereoscopic TV display reduces stereoscopic depth distorting while increasing stereoscopic depth resolution of images. Applicable to form of stereoscopic TV in which two views of scene presented by two video cameras to different fields of one monitor. According to concept, view of left camera shifts to left, and right camera, to right. Images made to overlap, so observed comfortably. Shifting done by inexpensive electronic circuitry.

  8. Stereoscopic radiographic images with thermal neutrons

    NASA Astrophysics Data System (ADS)

    Silvani, M. I.; Almeida, G. L.; Rogers, J. D.; Lopes, R. T.

    2011-10-01

    Spatial structure of an object can be perceived by the stereoscopic vision provided by eyes or by the parallax produced by movement of the object with regard to the observer. For an opaque object, a technique to render it transparent should be used, in order to make visible the spatial distribution of its inner structure, for any of the two approaches used. In this work, a beam of thermal neutrons at the main port of the Argonauta research reactor of the Instituto de Engenharia Nuclear in Rio de Janeiro/Brazil has been used as radiation to render the inspected objects partially transparent. A neutron sensitive Imaging Plate has been employed as a detector and after exposure it has been developed by a reader using a 0.5 μm laser beam, which defines the finest achievable spatial resolution of the acquired digital image. This image, a radiographic attenuation map of the object, does not represent any specific cross-section but a convoluted projection for each specific attitude of the object with regard to the detector. After taking two of these projections at different object attitudes, they are properly processed and the final image is viewed by a red and green eyeglass. For monochromatic images this processing involves transformation of black and white radiographies into red and white and green and white ones, which are afterwards merged to yield a single image. All the processes are carried out with the software ImageJ. Divergence of the neutron beam unfortunately spoils both spatial and contrast resolutions, which become poorer as object-detector distance increases. Therefore, in order to evaluate the range of spatial resolution corresponding to the 3D image being observed, a curve expressing spatial resolution against object-detector gap has been deduced from the Modulation Transfer Functions experimentally. Typical exposure times, under a reactor power of 170 W, were 6 min for both quantitative and qualitative measurements. In spite of its intrinsic constraints

  9. 21 CFR 886.1880 - Fusion and stereoscopic target.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Fusion and stereoscopic target. 886.1880 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device intended for use as a viewing object...

  10. 21 CFR 886.1880 - Fusion and stereoscopic target.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Fusion and stereoscopic target. 886.1880 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device intended for use as a viewing object...

  11. 21 CFR 886.1880 - Fusion and stereoscopic target.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Fusion and stereoscopic target. 886.1880 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device intended for use as a viewing object...

  12. 21 CFR 886.1880 - Fusion and stereoscopic target.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Fusion and stereoscopic target. 886.1880 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device intended for use as a viewing object...

  13. 21 CFR 886.1880 - Fusion and stereoscopic target.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fusion and stereoscopic target. 886.1880 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device intended for use as a viewing object...

  14. Stereoscopic contents authoring system for 3D DMB data service

    NASA Astrophysics Data System (ADS)

    Lee, BongHo; Yun, Kugjin; Hur, Namho; Kim, Jinwoong; Lee, SooIn

    2009-02-01

    This paper presents a stereoscopic contents authoring system that covers the creation and editing of stereoscopic multimedia contents for the 3D DMB (Digital Multimedia Broadcasting) data services. The main concept of 3D DMB data service is that, instead of full 3D video, partial stereoscopic objects (stereoscopic JPEG, PNG and MNG) are stereoscopically displayed on the 2D background video plane. In order to provide stereoscopic objects, we design and implement a 3D DMB content authoring system which provides the convenient and straightforward contents creation and editing functionalities. For the creation of stereoscopic contents, we mainly focused on two methods: CG (Computer Graphics) based creation and real image based creation. In the CG based creation scenario where the generated CG data from the conventional MAYA or 3DS MAX tool is rendered to generate the stereoscopic images by applying the suitable disparity and camera parameters, we use X-file for the direct conversion to stereoscopic objects, so called 3D DMB objects. In the case of real image based creation, the chroma-key method is applied to real video sequences to acquire the alpha-mapped images which are in turn directly converted to stereoscopic objects. The stereoscopic content editing module includes the timeline editor for both the stereoscopic video and stereoscopic objects. For the verification of created stereoscopic contents, we implemented the content verification module to verify and modify the contents by adjusting the disparity. The proposed system will leverage the power of stereoscopic contents creation for mobile 3D data service especially targeted for T-DMB with the capabilities of CG and real image based contents creation, timeline editing and content verification.

  15. Perceptual Depth Quality in Distorted Stereoscopic Images.

    PubMed

    Wang, Jiheng; Wang, Shiqi; Ma, Kede; Wang, Zhou

    2017-03-01

    Subjective and objective measurement of the perceptual quality of depth information in symmetrically and asymmetrically distorted stereoscopic images is a fundamentally important issue in stereoscopic 3D imaging that has not been deeply investigated. Here, we first carry out a subjective test following the traditional absolute category rating protocol widely used in general image quality assessment research. We find this approach problematic, because monocular cues and the spatial quality of images have strong impact on the depth quality scores given by subjects, making it difficult to single out the actual contributions of stereoscopic cues in depth perception. To overcome this problem, we carry out a novel subjective study where depth effect is synthesized at different depth levels before various types and levels of symmetric and asymmetric distortions are applied. Instead of following the traditional approach, we ask subjects to identify and label depth polarizations, and a depth perception difficulty index (DPDI) is developed based on the percentage of correct and incorrect subject judgements. We find this approach highly effective at quantifying depth perception induced by stereo cues and observe a number of interesting effects regarding image content dependency, distortion-type dependence, and the impact of symmetric versus asymmetric distortions. Furthermore, we propose a novel computational model for DPDI prediction. Our results show that the proposed model, without explicitly identifying image distortion types, leads to highly promising DPDI prediction performance. We believe that these are useful steps toward building a comprehensive understanding on 3D quality-of-experience of stereoscopic images.

  16. Stereoscopic display in a slot machine

    NASA Astrophysics Data System (ADS)

    Laakso, M.

    2012-03-01

    This paper reports the results of a user trial with a slot machine equipped with a stereoscopic display. The main research question was to find out what kind of added value does stereoscopic 3D (S-3D) bring to slot games? After a thorough literature survey, a novel gaming platform was designed and implemented. Existing multi-game slot machine "Nova" was converted to "3DNova" by replacing the monitor with an S-3D display and converting six original games to S-3D format. To evaluate the system, several 3DNova machines were put available for players for four months. Both qualitative and quantitative analysis was carried out from statistical values, questionnaires and observations. According to the results, people find the S-3D concept interesting but the technology is not optimal yet. Young adults and adults were fascinated by the system, older people were more cautious. Especially the need to wear stereoscopic glasses provide a challenge; ultimate system would probably use autostereoscopic technology. Also the games should be designed to utilize its full power. The main contributions of this paper are lessons learned from creating an S-3D slot machine platform and novel information about human factors related to stereoscopic slot machine gaming.

  17. Matte painting in stereoscopic synthetic imagery

    NASA Astrophysics Data System (ADS)

    Eisenmann, Jonathan; Parent, Rick

    2010-02-01

    While there have been numerous studies concerning human perception in stereoscopic environments, rules of thumb for cinematography in stereoscopy have not yet been well-established. To that aim, we present experiments and results of subject testing in a stereoscopic environment, similar to that of a theater (i.e. large flat screen without head-tracking). In particular we wish to empirically identify thresholds at which different types of backgrounds, referred to in the computer animation industry as matte paintings, can be used while still maintaining the illusion of seamless perspective and depth for a particular scene and camera shot. In monoscopic synthetic imagery, any type of matte painting that maintains proper perspective lines, depth cues, and coherent lighting and textures saves in production costs while still maintaining the illusion of an alternate cinematic reality. However, in stereoscopic synthetic imagery, a 2D matte painting that worked in monoscopy may fail to provide the intended illusion of depth because the viewer has added depth information provided by stereopsis. We intend to observe two stereoscopic perceptual thresholds in this study which will provide practical guidelines indicating when to use each of three types of matte paintings. We ran subject tests in two virtual testing environments, each with varying conditions. Data were collected showing how the choices of the users matched the correct response, and the resulting perceptual threshold patterns are discussed below.

  18. Stereoscopic wide field of view imaging system

    NASA Technical Reports Server (NTRS)

    Prechtl, Eric F. (Inventor); Sedwick, Raymond J. (Inventor); Jonas, Eric M. (Inventor)

    2011-01-01

    A stereoscopic imaging system incorporates a plurality of imaging devices or cameras to generate a high resolution, wide field of view image database from which images can be combined in real time to provide wide field of view or panoramic or omni-directional still or video images.

  19. Three-Dimensional Pointers for Stereoscopic Projection.

    ERIC Educational Resources Information Center

    Hayman, H. J. G.

    1984-01-01

    Because class size often limits student opportunity to handle individual models, teachers use stereoscopic projections to demonstrate structural features. Describes three-dimensional pointers for use with different projection systems so teachers can indicate a particular atom or bond to entire classes, avoiding the perspective problems inherent in…

  20. Using stereoscopic imaging for visualization applications

    SciTech Connect

    Adelson, S.J.

    1994-02-01

    The purpose of scientific visualization is to simplify the analysis of numerical data by rendering the information as an image. Even when the image is familiar, as in the case of terrain data, preconceptions about what the image should look like and deceptive image artifacts can create misconceptions about what information is actually contained in the scene. One way of aiding the development of unambiguous visualizations is to add stereoscopic depth to the image. Despite the recent proliferation of affordable stereoscopic viewing equipment, few researchers are at this time taking advantage of stereo in their visualizations. It is generally perceived that the rendering time will have to be doubled in order to generate the pair, and so stereoscopic viewing is sacrificed in the name of expedient rendering. We show that this perception is often invalid. The second half of a stereoscopic image can be generated from the first half for a fraction of the computational cost of complete rendering, usually no more than 50% of the cost and in many cases as little as 5%. Using the techniques presented here, the benefits of stereoscopy can be added to existing visualization systems for only a small cost over current single-frame rendering methods.

  1. Stereoscopic watermarking by horizontal noise mean shifting

    NASA Astrophysics Data System (ADS)

    Lee, Ji-Won; Kim, Hee-Dong; Choi, Hak-Yeol; Choi, Sung-Hee; Lee, Heung-Kyu

    2012-03-01

    Depth-image-based rendering (DIBR) is a method to represent a stereoscopic content. The DIBR consists of a monoscopic center view and an associated per-pixel depth map. Using these two components and given depth condition from a user, the DIBR renders left and right views. The advantages of DIBR are numerous. The user can choose not only the monoscopic or stereoscopic view selectively, but also the depth condition what he prefers when he watches a stereoscopic content. However, in the view of copyright protection, since not only the center view but also each left or right view can be used as a monoscopic content when they are illegally distributed, the watermark signal which is embedded in the center view must have an ability to protect the respective three views. In this study, we solve this problem by exploiting the horizontal noise mean shifting (HNMS) technique. We exploit the fact that the objects in the view are shifted only to horizontal way when the center view renders to the left and right views. Using this fact, the proposed stereoscopic watermarking scheme moves the mean of horizontal noise histogram which is invariant to horizontal shifting, and we achieve good performance as shown in the experimental results.

  2. Instant noodles: processing, quality, and nutritional aspects.

    PubMed

    Gulia, Neelam; Dhaka, Vandana; Khatkar, B S

    2014-01-01

    Noodles are one of the staple foods consumed in many Asian countries. Instant noodles have become internationally recognized food, and worldwide consumption is on the rise. The properties of instant noodles like taste, nutrition, convenience, safety, longer shelf-life, and reasonable price have made them popular. Quality factors important for instant noodles are color, flavor, and texture, cooking quality, rehydration rates during final preparation, and the presence or absence of rancid taste after extended storage. Microstructure of dough and noodles has been studied to understand the influence of ingredients and processing variables on the noodle quality by employing scanning electron microscopy. Applications of newer techniques like confocal laser scanning microscopy and epifluorescence light microscopy employed to understand the microstructure changes in dough and noodles have also been discussed. Sincere efforts of researchers are underway to improve the formulation, extend the shelf life, and promote universal fortification of instant noodles. Accordingly, many researchers are exploring the potential of noodle fortification as an effective public health intervention and improve its nutritional properties. This review focuses on the functionality of ingredients, unit operations involved, quality criteria for evaluation, recent trends in fortification, and current knowledge in relation to instant noodles.

  3. Generating Stereoscopic Television Images With One Camera

    NASA Technical Reports Server (NTRS)

    Coan, Paul P.

    1996-01-01

    Straightforward technique for generating stereoscopic television images involves use of single television camera translated laterally between left- and right-eye positions. Camera acquires one of images (left- or right-eye image), and video signal from image delayed while camera translated to position where it acquires other image. Length of delay chosen so both images displayed simultaneously or as nearly simultaneously as necessary to obtain stereoscopic effect. Technique amenable to zooming in on small areas within broad scenes. Potential applications include three-dimensional viewing of geological features and meteorological events from spacecraft and aircraft, inspection of workpieces moving along conveyor belts, and aiding ground and water search-and-rescue operations. Also used to generate and display imagery for public education and general information, and possible for medical purposes.

  4. Generating Stereoscopic Television Images With One Camera

    NASA Technical Reports Server (NTRS)

    Coan, Paul P.

    1996-01-01

    Straightforward technique for generating stereoscopic television images involves use of single television camera translated laterally between left- and right-eye positions. Camera acquires one of images (left- or right-eye image), and video signal from image delayed while camera translated to position where it acquires other image. Length of delay chosen so both images displayed simultaneously or as nearly simultaneously as necessary to obtain stereoscopic effect. Technique amenable to zooming in on small areas within broad scenes. Potential applications include three-dimensional viewing of geological features and meteorological events from spacecraft and aircraft, inspection of workpieces moving along conveyor belts, and aiding ground and water search-and-rescue operations. Also used to generate and display imagery for public education and general information, and possible for medical purposes.

  5. How crosstalk affects stereopsis in stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Huang, KuoChung; Yuan, Jy-Chyi; Tsai, Chao-Hsu; Hsueh, Wen-Jean; Wang, Nai-Yueh

    2003-05-01

    The ghost-image issue induced by crosstalk in stereoscopic, especially autostereoscopic, display systems has been believed to be a major factor to jeopardize stereopsis. Nevertheless, it is found that in some cases the stereopsis remains effective even with serious crosstalk. In fact, many other factors, such as contrast ratio, disparity, and monocular cues of the images, play important roles in the fusion of stereo images. In this paper, we study the factors in an image that may affect stereo fusion, and provide a macroscopic point of view to get a reasonable criterion of system crosstalk. Both natural and computer-generated images are used for detailed evaluation. Image processing techniques are adopted to produce desired characteristics. The results of this research shall be of reference value to content makers of stereoscopic displays, in addition to their designers.

  6. Light polarization in support of stereoscopic display

    NASA Astrophysics Data System (ADS)

    Walworth, Vivian K.

    2012-02-01

    The encoding of three-dimensional image pairs by polarization was proposed as early as the 1890s, perhaps stimulated by the popularity of stereoscopic photography, the proliferation of devices for viewing side-by-side stereoscopic images, and the invention of the anaglyph. The introduction of inexpensive sheet polarizing material gave rise to new three-dimensional technologies, starting in the 1930s with 16-mm black-and-white motion pictures projected by paired projectors equipped with orthogonally oriented polarizing filters. Further advances included the introduction of color, the concept of printing left- and right-eye images on a common carrier, and most recently the development of digital photography and the utilization of polarizers in both two- and three-dimensional digital color display.

  7. Stereoscopic Video Weld-Seam Tracker

    NASA Technical Reports Server (NTRS)

    Kennedy, Larry Z.

    1991-01-01

    Stereoscopic video camera and laser illuminator operates in conjunction with image-data-processing computer to locate weld seam and to map surface features in vicinity of seam. Intended to track seams to guide placement of welding torch in automatic welding system and to yield information on qualities of welds. More sensitive than prior optical seam trackers and suitable for use in production environment. Tracks nearly invisible gap between butted machined edges of two plates.

  8. Interactive stereoscopic viewer for cultural heritage

    NASA Astrophysics Data System (ADS)

    Abe, Nobuaki; Kawai, Takashi; Kawaguchi, Mami; Ando, Makoto

    2008-02-01

    The purpose of the research project reported here is to create more life-like representations of cultural heritage items by presenting stereoscopic images based on 3D data. In this paper, the authors report on the work of archiving heritage items in China's National Palace Museum and on the development of an interactive stereoscopic viewer system. A horizontal stereoscopic representation with interactivity is examined as a method of obtaining a "depth" sensation. The aim is to represent cultural heritage from a low level close to that of the real environment, such as in a museum, and to provide tactile sensation. The viewer system consists of a 3D display using Xpol, a touch panel, and a tilt encoder. the system is controlled by a Windows PC with custom software. The touch panel works for not only general interactions, such as moving the displayed 3D images, but also offers an unusual type of interaction known as "tracing". The tilt encoder detects the angle of the display and rotates the 3D images accordingly. These interactions control the coordinates and parallax of the 3D images in real time to provide an experience similar to holding the real object directly. In addition, the authors examine the effectiveness of the viewer system through a subjective evaluation.

  9. Usability of stereoscopic view in teleoperation

    NASA Astrophysics Data System (ADS)

    Boonsuk, Wutthigrai

    2015-03-01

    Recently, there are tremendous growths in the area of 3D stereoscopic visualization. The 3D stereoscopic visualization technology has been used in a growing number of consumer products such as the 3D televisions and the 3D glasses for gaming systems. This technology refers to the idea that human brain develops depth of perception by retrieving information from the two eyes. Our brain combines the left and right images on the retinas and extracts depth information. Therefore, viewing two video images taken at slightly distance apart as shown in Figure 1 can create illusion of depth [8]. Proponents of this technology argue that the stereo view of 3D visualization increases user immersion and performance as more information is gained through the 3D vision as compare to the 2D view. However, it is still uncertain if additional information gained from the 3D stereoscopic visualization can actually improve user performance in real world situations such as in the case of teleoperation.

  10. Stereoscopic Display on Computer Monitor Using a Single Wedge Prism

    NASA Astrophysics Data System (ADS)

    Park, Tae-Soo; Park, Chan-Young; Lee, Han-Bae; Park, Seung-Han

    2002-02-01

    We propose a novel stereoscopic display technique which uses only a single wedge prism. It can provide good depth perception from a stereoscopic pair image displayed on a computer monitor. One element of the stereoscopic pair image is inversely distorted to correct the deformation induced by the wedge prism. The computer simulation and experimental demonstration show that this technique can be successfully applied to the Internet environment.

  11. Analysis of physiological impact while reading stereoscopic radiographs

    NASA Astrophysics Data System (ADS)

    Unno, Yasuko Y.; Tajima, Takashi; Kuwabara, Takao; Hasegawa, Akira; Natsui, Nobutaka; Ishikawa, Kazuo; Hatada, Toyohiko

    2011-03-01

    A stereoscopic viewing technology is expected to improve diagnostic performance in terms of reading efficiency by adding one more dimension to the conventional 2D images. Although a stereoscopic technology has been applied to many different field including TV, movies and medical applications, physiological fatigue through reading stereoscopic radiographs has been concerned although no established physiological fatigue data have been provided. In this study, we measured the α-amylase concentration in saliva, heart rates and normalized tissue hemoglobin index (nTHI) in blood of frontal area to estimate physiological fatigue through reading both stereoscopic radiographs and the conventional 2D radiographs. In addition, subjective assessments were also performed. As a result, the pupil contraction occurred just after the reading of the stereoscopic images, but the subjective assessments regarding visual fatigue were nearly identical for the reading the conventional 2D and stereoscopic radiographs. The α-amylase concentration and the nTHI continued to decline while examinees read both 2D and stereoscopic images, which reflected the result of subjective assessment that almost half of the examinees reported to feel sleepy after reading. The subjective assessments regarding brain fatigue showed that there were little differences between 2D and stereoscopic reading. In summary, this study shows that the physiological fatigue caused by stereoscopic reading is equivalent to the conventional 2D reading including ocular fatigue and burden imposed on brain.

  12. Using a high-definition stereoscopic video system to teach microscopic surgery

    NASA Astrophysics Data System (ADS)

    Ilgner, Justus; Park, Jonas Jae-Hyun; Labbé, Daniel; Westhofen, Martin

    2007-02-01

    Introduction: While there is an increasing demand for minimally invasive operative techniques in Ear, Nose and Throat surgery, these operations are difficult to learn for junior doctors and demanding to supervise for experienced surgeons. The motivation for this study was to integrate high-definition (HD) stereoscopic video monitoring in microscopic surgery in order to facilitate teaching interaction between senior and junior surgeon. Material and methods: We attached a 1280x1024 HD stereo camera (TrueVisionSystems TM Inc., Santa Barbara, CA, USA) to an operating microscope (Zeiss ProMagis, Zeiss Co., Oberkochen, Germany), whose images were processed online by a PC workstation consisting of a dual Intel® Xeon® CPU (Intel Co., Santa Clara, CA). The live image was displayed by two LCD projectors @ 1280x768 pixels on a 1,25m rear-projection screen by polarized filters. While the junior surgeon performed the surgical procedure based on the displayed stereoscopic image, all other participants (senior surgeon, nurse and medical students) shared the same stereoscopic image from the screen. Results: With the basic setup being performed only once on the day before surgery, fine adjustments required about 10 minutes extra during the operation schedule, which fitted into the time interval between patients and thus did not prolong operation times. As all relevant features of the operative field were demonstrated on one large screen, four major effects were obtained: A) Stereoscopy facilitated orientation for the junior surgeon as well as for medical students. B) The stereoscopic image served as an unequivocal guide for the senior surgeon to demonstrate the next surgical steps to the junior colleague. C) The theatre nurse shared the same image, anticipating the next instruments which were needed. D) Medical students instantly share the information given by all staff and the image, thus avoiding the need for an extra teaching session. Conclusion: High definition

  13. Human factors involved in perception and action in a natural stereoscopic world: an up-to-date review with guidelines for stereoscopic displays and stereoscopic virtual reality (VR)

    NASA Astrophysics Data System (ADS)

    Perez-Bayas, Luis

    2001-06-01

    In stereoscopic perception of a three-dimensional world, binocular disparity might be thought of as the most important cue to 3D depth perception. Nevertheless, in reality there are many other factors involved before the 'final' conscious and subconscious stereoscopic perception, such as luminance, contrast, orientation, color, motion, and figure-ground extraction (pop-out phenomenon). In addition, more complex perceptual factors exist, such as attention and its duration (an equivalent of 'brain zooming') in relation to physiological central vision, In opposition to attention to peripheral vision and the brain 'top-down' information in relation to psychological factors like memory of previous experiences and present emotions. The brain's internal mapping of a pure perceptual world might be different from the internal mapping of a visual-motor space, which represents an 'action-directed perceptual world.' In addition, psychological factors (emotions and fine adjustments) are much more involved in a stereoscopic world than in a flat 2D-world, as well as in a world using peripheral vision (like VR, using a curved perspective representation, and displays, as natural vision does) as opposed to presenting only central vision (bi-macular stereoscopic vision) as in the majority of typical stereoscopic displays. Here is presented the most recent and precise information available about the psycho-neuro- physiological factors involved in the perception of stereoscopic three-dimensional world, with an attempt to give practical, functional, and pertinent guidelines for building more 'natural' stereoscopic displays.

  14. Analysis of individual variability and habituation in stereoscopic radiography

    NASA Astrophysics Data System (ADS)

    Unno, Yasuko Y.; Kuwabara, Takao; Uzenoff, Robert A.; Natsui, Nobutaka; Ishikawa, Kazuo

    2013-03-01

    In our previous stereoscopic image for medical use research, we reported that observers found it is easier to identify target objects in stereoscopic images than in two dimensional images, however, we found that mental and visual fatigue levels are equivalent in viewing the stereoscopic and the two dimensional images. We reported that a number of users dislike the sensations accompanying stereoscopic vision. Hence, we studied personal variation of stereoscopic visibility and the training effect for the stereoscopic visibility in this research. Simulated images, in which prepared calcifications were arranged at parallactic angles between +/-2° to +/-15° at object heights from 40 to 80mm, were displayed on a stereoscopic 3D display. Seven observers were selected to judge the achievement of stereoscopic vision (stereopsis) and their visibility was determined. The observers were asked to point the stereoscopic cursor of the 3D mammography viewer at the simulated calcifications and the accuracy rates were determined. Subsequently, re-examination was implemented after 3D visual training for 15 to 20 minutes per day for two weeks, and the visibility and accuracy rates were measured again. We found individual differences in the parallactic angles at which stereopsis was realized. Moreover, the parallactic angles of stereopsis widened through training and the average visibility improved from 69% to 84% as the result of training. Furthermore, the average accuracy rates improved from 53% to 60% the accuracy of depth commands improved. This suggests that observers who are weak in stereoscopic vision can be trained to be better at stereoscopic viewing.

  15. Using Instant Messaging for Online Reference Service

    ERIC Educational Resources Information Center

    Forster, Shirley

    2006-01-01

    Many libraries are using co-browsing chat products to provide reference services to their patrons, whilst their patrons are online and using the internet. The concept of such an online service is highly desirable, but many libraries are concerned that they will never be able to afford such a system. This may have changed: Instant Messaging (IM)…

  16. Intercultural Learning via Instant Messenger Interaction

    ERIC Educational Resources Information Center

    Jin, Li; Erben, Tony

    2007-01-01

    This paper reports on a qualitative study investigating the viability of instant messenger (IM) interaction to facilitate intercultural learning in a foreign language class. Eight students in a Chinese as a foreign language (CFL) class participated in the study. Each student was paired with a native speaker (NS) of Chinese, and each pair…

  17. Instant Messaging Reference: How Does It Compare?

    ERIC Educational Resources Information Center

    Desai, Christina M.

    2003-01-01

    Compares a digital reference service that uses instant messaging with traditional, face-to-face reference based on experiences at the Southern Illinois University library. Addresses differences in reference questions asked, changes in the reference transaction, student expectations, bibliographic instruction, and librarian attitudes and procedures…

  18. Creating an Instant Messaging Reference System.

    ERIC Educational Resources Information Center

    Fagan, Jody Condit; Calloway, Michele

    2001-01-01

    Discussion of library digital reference services focuses on the features of instant messaging reference systems and the in-house development of a system that incorporates them at Southern Illinois University at Carbondale. Summarizes and evaluates library chat system features and compares commercial software that is available. (Author/LRW)

  19. 21 CFR 137.170 - Instantized flours.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Instantized flours. 137.170 Section 137.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized...

  20. 21 CFR 137.170 - Instantized flours.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Instantized flours. 137.170 Section 137.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized...

  1. Digital stereoscopic cinema: the 21st century

    NASA Astrophysics Data System (ADS)

    Lipton, Lenny

    2008-02-01

    Over 1000 theaters in more than a dozen countries have been outfitted with digital projectors using the Texas Instruments DLP engine equipped to show field-sequential 3-D movies using the polarized method of image selection. Shuttering eyewear and advanced anaglyph products are also being deployed for image selection. Many studios are in production with stereoscopic films, and some have committed to producing their entire output of animated features in 3-D. This is a time of technology change for the motion picture industry.

  2. 7 CFR 58.249 - Instant nonfat dry milk.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Instant nonfat dry milk. 58.249 Section 58.249... Products Bearing Usda Official Identification § 58.249 Instant nonfat dry milk. (a) Only instant nonfat dry milk manufactured and packaged in accordance with the requirements of this part and with the...

  3. Preservice Teachers' Perceptions of Instant Messaging in Two Educational Contexts

    ERIC Educational Resources Information Center

    Doering, Aaron; Lewis, Cynthia; Veletsianos, George; Nichols-Besel, Kristen

    2008-01-01

    Using an activity theory framework, we investigate how preservice teachers and middle school students utilized instant messaging in educational contexts and the impact of instant messaging on the development of community among preservice teachers. Qualitative results from six focus groups and two personal interviews indicate that instant messaging…

  4. 7 CFR 58.249 - Instant nonfat dry milk.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Instant nonfat dry milk. 58.249 Section 58.249... Products Bearing Usda Official Identification § 58.249 Instant nonfat dry milk. (a) Only instant nonfat dry milk manufactured and packaged in accordance with the requirements of this part and with the applicable...

  5. 7 CFR 58.249 - Instant nonfat dry milk.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Instant nonfat dry milk. 58.249 Section 58.249... Products Bearing Usda Official Identification § 58.249 Instant nonfat dry milk. (a) Only instant nonfat dry milk manufactured and packaged in accordance with the requirements of this part and with the applicable...

  6. 7 CFR 58.249 - Instant nonfat dry milk.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Instant nonfat dry milk. 58.249 Section 58.249... Products Bearing Usda Official Identification § 58.249 Instant nonfat dry milk. (a) Only instant nonfat dry milk manufactured and packaged in accordance with the requirements of this part and with the applicable...

  7. 7 CFR 58.249 - Instant nonfat dry milk.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Instant nonfat dry milk. 58.249 Section 58.249... Products Bearing Usda Official Identification § 58.249 Instant nonfat dry milk. (a) Only instant nonfat dry milk manufactured and packaged in accordance with the requirements of this part and with the...

  8. An HTML Tool for Production of Interactive Stereoscopic Compositions.

    PubMed

    Chistyakov, Alexey; Soto, Maria Teresa; Martí, Enric; Carrabina, Jordi

    2016-12-01

    The benefits of stereoscopic vision in medical applications were appreciated and have been thoroughly studied for more than a century. The usage of the stereoscopic displays has a proven positive impact on performance in various medical tasks. At the same time the market of 3D-enabled technologies is blooming. New high resolution stereo cameras, TVs, projectors, monitors, and head mounted displays become available. This equipment, completed with a corresponding application program interface (API), could be relatively easy implemented in a system. Such complexes could open new possibilities for medical applications exploiting the stereoscopic depth. This work proposes a tool for production of interactive stereoscopic graphical user interfaces, which could represent a software layer for web-based medical systems facilitating the stereoscopic effect. Further the tool's operation mode and the results of the conducted subjective and objective performance tests will be exposed.

  9. Stereoscopic Depth Perception during Binocular Rivalry.

    PubMed

    Andrews, Timothy J; Holmes, David

    2011-01-01

    When we view nearby objects, we generate appreciably different retinal images in each eye. Despite this, the visual system can combine these different images to generate a unified view that is distinct from the perception generated from either eye alone (stereopsis). However, there are occasions when the images in the two eyes are too disparate to fuse. Instead, they alternate in perceptual dominance, with the image from one eye being completely excluded from awareness (binocular rivalry). It has been thought that binocular rivalry is the default outcome when binocular fusion is not possible. However, other studies have reported that stereopsis and binocular rivalry can coexist. The aim of this study was to address whether a monocular stimulus that is reported to be suppressed from awareness can continue to contribute to the perception of stereoscopic depth. Our results showed that stereoscopic depth perception was still evident when incompatible monocular images differing in spatial frequency, orientation, spatial phase, or direction of motion engage in binocular rivalry. These results demonstrate a range of conditions in which binocular rivalry and stereopsis can coexist.

  10. Stereoscopic reconfiguration for 3D displays

    NASA Astrophysics Data System (ADS)

    Houde, Jean-Christophe; Jodoin, Pierre-Marc; Desch"nes, François

    2012-03-01

    In this paper, we present a method to reconfigure 3D movies in order to minimize distortion when seen on a different display than the one it has been configured for. By their very nature, 3D broadcasts come with a stereoscopic pair to be seen by the left and right eyes. However, according to reasons that we ought to explain in the paper, the cameras used to shoot a movie are calibrated according to specific viewing parameters such as the screen size, the viewing distance and the eye separation. As a consequence, a 3D broadcast seen on a different display (say a home theater or a PC screen) than the one it has been configured for (say an IMAX R screen) will suffer from noticeable distortions. In this paper, we describe the relationship between the size of the 3D display, the position of the observer, and the intrinsic and extrinsic parameters of the cameras. With this information, we propose a method to reorganize the stereoscopic pair in order to minimize distortion when seen on an arbitrary display. In addition to the raw video pair, our method uses the viewing distance, a rough estimate of the 3D scene, and some basic information on the 3D display. An inpainting technique is used to fill disoccluded areas.

  11. Stereoscopic Depth Perception during Binocular Rivalry

    PubMed Central

    Andrews, Timothy J.; Holmes, David

    2011-01-01

    When we view nearby objects, we generate appreciably different retinal images in each eye. Despite this, the visual system can combine these different images to generate a unified view that is distinct from the perception generated from either eye alone (stereopsis). However, there are occasions when the images in the two eyes are too disparate to fuse. Instead, they alternate in perceptual dominance, with the image from one eye being completely excluded from awareness (binocular rivalry). It has been thought that binocular rivalry is the default outcome when binocular fusion is not possible. However, other studies have reported that stereopsis and binocular rivalry can coexist. The aim of this study was to address whether a monocular stimulus that is reported to be suppressed from awareness can continue to contribute to the perception of stereoscopic depth. Our results showed that stereoscopic depth perception was still evident when incompatible monocular images differing in spatial frequency, orientation, spatial phase, or direction of motion engage in binocular rivalry. These results demonstrate a range of conditions in which binocular rivalry and stereopsis can coexist. PMID:21960966

  12. Debugging Parallel Programs with Instant Replay.

    DTIC Science & Technology

    1986-09-01

    collected during a single execution. Behavioral Abstraction (BA) is typical of this approach 121. BA provides a mechanism for the hierarhical definition ...exclusive access to the object. This description of a CREW access protocol is intended to be illustrative, not definitive . Instant Replay requires...slightly beyond 32 processors because the additional communication involved is not justified by the pin in paralelism 1141. A naive placement of

  13. Instant curvature measurement for microcantilever sensors

    SciTech Connect

    Jeon, Sangmin; Thundat, Thomas

    2004-08-09

    A multiple-point deflection technique has been developed for the instant measurement of microcantilever curvature. Eight light-emitting diodes are focused on various positions of a gold-coated silicon cantilever through optical fibers, and temperature change or chemical adsorption induces cantilever bending. The deflection at each point on the cantilever is measured with subnanometer precision by a position-sensitive detector, and thus the curvature of the cantilever is obtained.

  14. Biorefinery of instant noodle waste to biofuels.

    PubMed

    Yang, Xiaoguang; Lee, Sang Jun; Yoo, Hah Young; Choi, Han Suk; Park, Chulhwan; Kim, Seung Wook

    2014-05-01

    Instant noodle waste, one of the main residues of the modern food industry, was employed as feedstock to convert to valuable biofuels. After isolation of used oil from the instant noodle waste surface, the starch residue was converted to bioethanol by Saccharomyces cerevisiae K35 with simultaneous saccharification and fermentation (SSF). The maximum ethanol concentration and productivity was 61.1g/l and 1.7 g/lh, respectively. After the optimization of fermentation, ethanol conversion rate of 96.8% was achieved within 36 h. The extracted oil was utilized as feedstock for high quality biodiesel conversion with typical chemical catalysts (KOH and H2SO4). The optimum conversion conditions for these two catalysts were estimated; and the highest biodiesel conversion rates were achieved 98.5% and 97.8%, within 2 and 3h, respectively. The high conversion rates of both bioethanol and biodiesel demonstrate that novel substrate instant noodle waste can be an attractive biorefinery feedstock in the biofuels industry. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Preparation of partially decaffeinated instant green tea.

    PubMed

    Ye, Jian-Hui; Liang, Yue-Rong; Jin, Jing; Liang, Hue-Ling; Du, Ying-Ying; Lu, Jian-Liang; Ye, Qian; Lin, Chen

    2007-05-02

    The caffeine level of instant tea extracted from decaffeinated leaf tea with 4.0 mg g-1 caffeine is commonly above 10.0 mg g-1, the maximum limit of caffeine for decaffeinated instant tea. Further removal of caffeine by active carbon (AC) from the green tea extract was investigated. It showed that the removal of caffeine from the tea extract solutions depended on the treatment time and tea extract concentration while the ethanol concentration and pH had little effect on the removal of caffeine. According to the removal of caffeine and the ratio of total catechins to caffeine in the tested samples, the optimum decaffeination conditions were determined to be as follows: tea extract concentration 15-30 g L-1 for common tea extract but higher for partially decaffeinated tea leaf extract; ratio of tea solution to AC, 100 mL:4 g; treatment time, 4 h; and natural tea extract pH. Instant tea powder extracted from partially decaffeinated leaf tea with a caffeine level of 4.03 mg g-1 and further decaffeinated by AC had a caffeine level of 7.81 mg g-1, which was 31% lower than that without AC treatment.

  16. Stereoscopic 3D video games and their effects on engagement

    NASA Astrophysics Data System (ADS)

    Hogue, Andrew; Kapralos, Bill; Zerebecki, Chris; Tawadrous, Mina; Stanfield, Brodie; Hogue, Urszula

    2012-03-01

    With television manufacturers developing low-cost stereoscopic 3D displays, a large number of consumers will undoubtedly have access to 3D-capable televisions at home. The availability of 3D technology places the onus on content creators to develop interesting and engaging content. While the technology of stereoscopic displays and content generation are well understood, there are many questions yet to be answered surrounding its effects on the viewer. Effects of stereoscopic display on passive viewers for film are known, however video games are fundamentally different since the viewer/player is actively (rather than passively) engaged in the content. Questions of how stereoscopic viewing affects interaction mechanics have previously been studied in the context of player performance but very few have attempted to quantify the player experience to determine whether stereoscopic 3D has a positive or negative influence on their overall engagement. In this paper we present a preliminary study of the effects stereoscopic 3D have on player engagement in video games. Participants played a video game in two conditions, traditional 2D and stereoscopic 3D and their engagement was quantified using a previously validated self-reporting tool. The results suggest that S3D has a positive effect on immersion, presence, flow, and absorption.

  17. The importance of accurate convergence in addressing stereoscopic visual fatigue

    NASA Astrophysics Data System (ADS)

    Mayhew, Christopher A.

    2015-03-01

    Visual fatigue (asthenopia) continues to be a problem in extended viewing of stereoscopic imagery. Poorly converged imagery may contribute to this problem. In 2013, the Author reported that in a study sample a surprisingly high number of 3D feature films released as stereoscopic Blu-rays contained obvious convergence errors.1 The placement of stereoscopic image convergence can be an "artistic" call, but upon close examination, the sampled films seemed to have simply missed their intended convergence location. This failure maybe because some stereoscopic editing tools do not have the necessary fidelity to enable a 3D editor to obtain a high degree of image alignment or set an exact point of convergence. Compounding this matter further is the fact that a large number of stereoscopic editors may not believe that pixel accurate alignment and convergence is necessary. The Author asserts that setting a pixel accurate point of convergence on an object at the start of any given stereoscopic scene will improve the viewer's ability to fuse the left and right images quickly. The premise is that stereoscopic performance (acuity) increases when an accurately converged object is available in the image for the viewer to fuse immediately. Furthermore, this increased viewer stereoscopic performance should reduce the amount of visual fatigue associated with longer-term viewing because less mental effort will be required to perceive the imagery. To test this concept, we developed special stereoscopic imagery to measure viewer visual performance with and without specific objects for convergence. The Company Team conducted a series of visual tests with 24 participants between 25 and 60 years of age. This paper reports the results of these tests.

  18. Evaluating methods for controlling depth perception in stereoscopic cinematography

    NASA Astrophysics Data System (ADS)

    Sun, Geng; Holliman, Nick

    2009-02-01

    Existing stereoscopic imaging algorithms can create static stereoscopic images with perceived depth control function to ensure a compelling 3D viewing experience without visual discomfort. However, current algorithms do not normally support standard Cinematic Storytelling techniques. These techniques, such as object movement, camera motion, and zooming, can result in dynamic scene depth change within and between a series of frames (shots) in stereoscopic cinematography. In this study, we empirically evaluate the following three types of stereoscopic imaging approaches that aim to address this problem. (1) Real-Eye Configuration: set camera separation equal to the nominal human eye interpupillary distance. The perceived depth on the display is identical to the scene depth without any distortion. (2) Mapping Algorithm: map the scene depth to a predefined range on the display to avoid excessive perceived depth. A new method that dynamically adjusts the depth mapping from scene space to display space is presented in addition to an existing fixed depth mapping method. (3) Depth of Field Simulation: apply Depth of Field (DOF) blur effect to stereoscopic images. Only objects that are inside the DOF are viewed in full sharpness. Objects that are far away from the focus plane are blurred. We performed a human-based trial using the ITU-R BT.500-11 Recommendation to compare the depth quality of stereoscopic video sequences generated by the above-mentioned imaging methods. Our results indicate that viewers' practical 3D viewing volumes are different for individual stereoscopic displays and viewers can cope with much larger perceived depth range in viewing stereoscopic cinematography in comparison to static stereoscopic images. Our new dynamic depth mapping method does have an advantage over the fixed depth mapping method in controlling stereo depth perception. The DOF blur effect does not provide the expected improvement for perceived depth quality control in 3D cinematography

  19. Design of monocular multiview stereoscopic 3D display

    NASA Astrophysics Data System (ADS)

    Sakamoto, Kunio; Saruta, Kazuki; Takeda, Kazutoki

    2001-06-01

    A 3D head mounted display (HMD) system is useful for constructing a virtual space. The authors have developed a 3D HMD system using the monocular stereoscopic display. This paper shows that the 3D vision system using the monocular stereoscopic display and capturing camera builds a 3D virtual space for a telemanipulation using a captured real 3D image. In this paper, we propose the monocular stereoscopic 3D display and capturing camera for a tele- manipulation system. In addition, we describe the result of depth estimation using the multi-focus retinal images.

  20. Temporal sampling requirements for stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Green, Marc

    1992-06-01

    A series of three experiments examined temporal aliasing in stereoscopic displays. The first experiment compared aliasing in frontal plane motion of different disparities, while the second compared aliasing for motion in different depth directions. The results showed little effect of viewing conditions on perceived aliasing. The third experiment tested whether there was a binocular motion mechanism which integrated temporal sampling in the two eyes. The results were consistent with the first two studies in suggesting that aliasing is generated only by monocular motion signals. The data have both practical and theoretical implications: (1) motion produced by means of LCD glasses requires double the sampling rate needed for motion created by anaglyph methods, and (2) the short-range motion system is monocular.

  1. Optical scanning holography for stereoscopic display

    NASA Astrophysics Data System (ADS)

    Liu, Jung-Ping; Wen, Hsuan-Hsuan

    2016-10-01

    Optical Scanning Holography (OSH) is a scanning-type digital holographic recording technique. One of OSH's most important properties is that the OSH can record an incoherent hologram, which is free of speckle and thus is suitable for the applications of holographic display. The recording time of a scanning hologram is proportional to the sampling resolution. Hence the viewing angle as well as the resolution of a scanning hologram is limited for avoid too long recording. As a result, the viewing angle is not large enough for optical display. To solve this problem, we recorded two scanning holograms at different viewing angles. The two holograms are synthesized to a single stereoscopic hologram with two main viewing angles. In displaying, two views at the two main viewing angles are reconstructed. Because both views contain full-depth-resolved 3D scenes, the problem of accommodation conflict in conventional stereogram is avoided.

  2. Cooperative neural processes involved in stereoscopic acuity.

    PubMed

    Westheimer, G

    1979-08-01

    Results of psychophysical experiments are reported showing that synchrony, appropriate relative placement, and absence of standing disparity are important conditions to be met by members of a target configuration if they are to participate in the cooperative neural processes leading to the best disparity discrimination. Consecutive binocular presentation of the members of a stereo target decreases stereoacuity by a factor of about 10, and a step disparity displacement of a single line target needs to be larger still to be detected as a depth stimulus. A standing disaprity of even one minute of arc at least doubles the disaprity disxrimination threshold. It is postulated that a differencing mechanism operates on the depth signal of individual features; the temporal and spatial optima of target presentation for stereoscopic acuity outline the character of the concerned operations.

  3. LED based full color stereoscopic projection system

    NASA Astrophysics Data System (ADS)

    Bogaert, Lawrence; Meuret, Youri; Van Giel, Bart; Thienpont, Hugo

    2007-02-01

    We present a compact light emitting diode (LED) based projection system with potential for stereoscopic viewing. The optical core consists of four polarizing beam splitters (PBS), positioned in a cross configuration, with wavelength selective half wave plates placed between them. Four liquid crystal on silicon (LCoS) panels are located at the exterior facets of two PBSs in opposite corners of the cuboid. The illumination system combines individual LED sources and ensures telecentric illumination through the optical core. This architecture gives rise to two light paths that independently generate two linear polarized images with orthogonal polarization direction. When the observer wears polarization sensitive eyeglasses and a polarization maintaining screen is used, each eye will see a different projected image such that three-dimensional (3-D) viewing can be perceived. On the other hand, 2-D vision is possible by projecting two identical images.

  4. Stereoscopic eye exercises and visual acuity.

    PubMed

    Lasky, D I; Lasky, A M

    1990-12-01

    The present study was done to investigate the effects of stereoscopic eye exercises on visual acuity, testing 20 college students (9 men and 11 women, ages 18 to 35 yr.). Visual acuity was assessed before and after the exercises through six tests: far vision--both eyes, right eye; left eye; and near vision--both eyes, right eye, left eye. Statistically significant improvements were found on five of the six pretest-posttest comparisons: far vision--both eyes, right eye, and left eye; and near vision--both eyes, right eye, and left eye. Changes in far vision, right eye only approached significance. Limitations of the present study were discussed, and recommendations for research were presented.

  5. Improvements in the Visualization of Stereoscopic 3D Imagery

    NASA Astrophysics Data System (ADS)

    Gurrieri, Luis E.

    2015-09-01

    A pleasant visualization of stereoscopic imagery must take into account factors that may produce eye strain and fatigue. Fortunately, our binocular vision system has embedded mechanisms to perceive depth for extended periods of time without producing eye fatigue; however, stereoscopic imagery may still induce visual discomfort in certain displaying scenarios. An important source of eye fatigue originates in the conflict between vergence eye movement and focusing mechanisms. Today's eye-tracking technology makes possible to know the viewers' gaze direction; hence, 3D imagery can be dynamically corrected based on this information. In this paper, I introduce a method to improve the visualization of stereoscopic imagery on planar displays based on emulating vergence and accommodation mechanisms of binocular human vision. Unlike other methods to improve the visual comfort that introduce depth distortions, in the stereoscopic visual media, this technique aims to produce a gentler and more natural binocular viewing experience without distorting the original depth of the scene.

  6. Spatiotemporal limitations on vernier and stereoscopic alignment acuity

    NASA Astrophysics Data System (ADS)

    Tyler, Christopher W.; Schor, Clifton M.; Coletta, Nancy J.

    1992-06-01

    Stereoscopic and monocular alignment acuity were measured using sinusoidal displacements in time, space, and disparity of a single line stimulus. The stereoscopic detectability was not limited by the sensitivity for the monocular components of the spatio-temporal stereo- alignment target. In fact, the two tasks seemed to be controlled by largely independent processes. Monocular sensitivity was best at high spatial perturbation frequencies, almost independent of temporal frequency, while stereoscopic sensitivity was best at low temporal and medium spatial frequencies, and its surface had a substantially different morphology. Under these dynamic conditions the lowest thresholds of either kind were of the order of 10 arc sec, setting stringent limitations on the accuracy of stereoscopic displays. The spatio- temporal surfaces we measured show regions where sensitivity is reduced by an order of magnitude, suggesting modes in which dynamic human stereopsis is more tolerant of perturbations than suggested by classical data.

  7. Stereoscopic model for depth-fused 3D (DFD) display

    NASA Astrophysics Data System (ADS)

    Yamamoto, H.; Sonobe, H.; Tsunakawa, A.; Kawakami, J.; Suyama, S.

    2014-03-01

    This paper proposes a stereoscopic model for DFD display that explains the continuous depth modulation and protruding depth perception. The model is composed of four steps: preparation of DFD images, geometrical calculation of viewed images, human visual function for detecting intensity changes, and stereoscopic depth perception. In this paper, two types of displayed images for DFD display are prepared: the former pairs are for conventional DFD, where a fused image is located between the layered images; the latter pairs are for protruding DFD, where a fused image is located closer than the foreground image or further than the background image. Viewed images at both eye positions are simulated geometrically in computer vision optics model. In order to detect intensity changes, we have utilized Laplacian operation on a Gaussian blurred image. Stereoscopic depths are calculated by matching the zero crossing position on the Laplacian operated images. It is revealed that our stereoscopic model explains both conventional and protruding DFDs.

  8. Auto-stereoscopic 3D displays with reduced crosstalk.

    PubMed

    Lee, Chulhee; Seo, Guiwon; Lee, Jonghwa; Han, Tae-hwan; Park, Jong Geun

    2011-11-21

    In this paper, we propose new auto-stereoscopic 3D displays that substantially reduce crosstalk. In general, it is difficult to eliminate crosstalk in auto-stereoscopic 3D displays. Ideally, the parallax barrier can eliminate crosstalk for a single viewer at the ideal position. However, due to variations in the viewing distance and the interpupillary distance, crosstalk is a problem in parallax barrier displays. In this paper, we propose 3-dimensional barriers, which can significantly reduce crosstalk.

  9. Bitrate reduction techniques for stereoscopic digital cinema distribution

    NASA Astrophysics Data System (ADS)

    Smith, Michael D.; Villasenor, John

    2008-01-01

    We consider the performance of two candidate approaches to compressing stereoscopic digital cinema distribution images: decorrelation transforms and disparity compensation. We show that disparity compensation generally can provide superior performance when significant disparity exists, and furthermore, that the consideration of vertical displacement can be an important factor in maximizing this performance under certain conditions. For context, we also provide details about the current state of both 2D and stereoscopic digital cinema distribution as of the end of the year 2007.

  10. Adaptive instant record signals applied to shallow water detection

    NASA Astrophysics Data System (ADS)

    Folégot, Thomas; de Rosny, Julien; Prada, Claire; Fink, Mathias

    2004-05-01

    Time reversal arrays are becoming common tools whether for detection, tomography or communication. These applications require the measurement of the response from the array to one or several receivers. The most natural way to record different impulse responses between several points is to generate pulses successively from each emitting point and directly record all the impulse responses on the recording points. However, this method is very time consuming and inefficient in terms of signal-to-noise ratio. Hence, in this work, we propose an original way of sending continuous signals simultaneously from all the sources, recording all the pressure fields on the receivers and processing them in order to extract the exact impulse responses by matched filter. To this end, the signals are adapted to the environment and, more specifically, to highly dispersive media. These adaptive instant records signals (AIRS) are used experimentally to detect targets using the time reversal operator decomposition method. The quality of the 15×15 transfer functions acquired simultaneously, and therefore, the detection capability is demonstrated in shallow water in the presence of bottom absorption and reverberation. Finally, the connection of AIRS with CDMA and FDMA that are two coding techniques used in telecommunication is shown.

  11. Examination of 3D visual attention in stereoscopic video content

    NASA Astrophysics Data System (ADS)

    Huynh-Thu, Quan; Schiatti, Luca

    2011-03-01

    Recent advances in video technology and digital cinema have made it possible to produce entertaining 3D stereoscopic content that can be viewed for an extended duration without necessarily causing extreme fatigue, visual strain and discomfort. Viewers focus naturally their attention on specific areas of interest in their visual field. Visual attention is an important aspect of perception and its understanding is therefore an important aspect for the creation of 3D stereoscopic content. Most of the studies on visual attention have focused on the case of still images or 2D video. Only a very few studies have investigated eye movement patterns in 3D stereoscopic moving sequences, and how these may differ from viewing 2D video content. In this paper, we present and discuss the results of a subjective experiment that we conducted using an eye-tracking apparatus to record observers' gaze patterns. Participants were asked to watch the same set of video clips in a free-viewing task. Each clip was shown in a 3D stereoscopic version and 2D version. Our results indicate that the extent of areas of interests is not necessarily wider in 3D. We found a very strong content dependency in the difference of density and locations of fixations between 2D and 3D stereoscopic content. However, we found that saccades were overall faster and that fixation durations were overall lower when observers viewed the 3D stereoscopic version.

  12. Geometrically Consistent Stereoscopic Image Editing Using Patch-Based Synthesis.

    PubMed

    Luo, Sheng-Jie; Sun, Ying-Tse; Shen, I-Chao; Chen, Bing-Yu; Chuang, Yung-Yu

    2015-01-01

    This paper presents a patch-based synthesis framework for stereoscopic image editing. The core of the proposed method builds upon a patch-based optimization framework with two key contributions: First, we introduce a depth-dependent patch-pair similarity measure for distinguishing and better utilizing image contents with different depth structures. Second, a joint patch-pair search is proposed for properly handling the correlation between two views. The proposed method successfully overcomes two main challenges of editing stereoscopic 3D media: (1) maintaining the depth interpretation, and (2) providing controllability of the scene depth. The method offers patch-based solutions to a wide variety of stereoscopic image editing problems, including depth-guided texture synthesis, stereoscopic NPR, paint by depth, content adaptation, and 2D to 3D conversion. Several challenging cases are demonstrated to show the effectiveness of the proposed method. The results of user studies also show that the proposed method produces stereoscopic images with good stereoscopics and visual quality.

  13. Stereoscopic Integrated Imaging Goggles for Multimodal Intraoperative Image Guidance.

    PubMed

    Mela, Christopher A; Patterson, Carrie; Thompson, William K; Papay, Francis; Liu, Yang

    2015-01-01

    We have developed novel stereoscopic wearable multimodal intraoperative imaging and display systems entitled Integrated Imaging Goggles for guiding surgeries. The prototype systems offer real time stereoscopic fluorescence imaging and color reflectance imaging capacity, along with in vivo handheld microscopy and ultrasound imaging. With the Integrated Imaging Goggle, both wide-field fluorescence imaging and in vivo microscopy are provided. The real time ultrasound images can also be presented in the goggle display. Furthermore, real time goggle-to-goggle stereoscopic video sharing is demonstrated, which can greatly facilitate telemedicine. In this paper, the prototype systems are described, characterized and tested in surgeries in biological tissues ex vivo. We have found that the system can detect fluorescent targets with as low as 60 nM indocyanine green and can resolve structures down to 0.25 mm with large FOV stereoscopic imaging. The system has successfully guided simulated cancer surgeries in chicken. The Integrated Imaging Goggle is novel in 4 aspects: it is (a) the first wearable stereoscopic wide-field intraoperative fluorescence imaging and display system, (b) the first wearable system offering both large FOV and microscopic imaging simultaneously, (c) the first wearable system that offers both ultrasound imaging and fluorescence imaging capacities, and (d) the first demonstration of goggle-to-goggle communication to share stereoscopic views for medical guidance.

  14. Evaluation of stereoscopic 3D displays for image analysis tasks

    NASA Astrophysics Data System (ADS)

    Peinsipp-Byma, E.; Rehfeld, N.; Eck, R.

    2009-02-01

    In many application domains the analysis of aerial or satellite images plays an important role. The use of stereoscopic display technologies can enhance the image analyst's ability to detect or to identify certain objects of interest, which results in a higher performance. Changing image acquisition from analog to digital techniques entailed the change of stereoscopic visualisation techniques. Recently different kinds of digital stereoscopic display techniques with affordable prices have appeared on the market. At Fraunhofer IITB usability tests were carried out to find out (1) with which kind of these commercially available stereoscopic display techniques image analysts achieve the best performance and (2) which of these techniques achieve a high acceptance. First, image analysts were interviewed to define typical image analysis tasks which were expected to be solved with a higher performance using stereoscopic display techniques. Next, observer experiments were carried out whereby image analysts had to solve defined tasks with different visualization techniques. Based on the experimental results (performance parameters and qualitative subjective evaluations of the used display techniques) two of the examined stereoscopic display technologies were found to be very good and appropriate.

  15. Interactive floating windows: a new technique for stereoscopic video games

    NASA Astrophysics Data System (ADS)

    Zerebecki, Chris; Stanfield, Brodie; Tawadrous, Mina; Buckstein, Daniel; Hogue, Andrew; Kapralos, Bill

    2012-03-01

    The film industry has a long history of creating compelling experiences in stereoscopic 3D. Recently, the video game as an artistic medium has matured into an effective way to tell engaging and immersive stories. Given the current push to bring stereoscopic 3D technology into the consumer market there is considerable interest to develop stereoscopic 3D video games. Game developers have largely ignored the need to design their games specifically for stereoscopic 3D and have thus relied on automatic conversion and driver technology. Game developers need to evaluate solutions used in other media, such as film, to correct perceptual problems such as window violations, and modify or create new solutions to work within an interactive framework. In this paper we extend the dynamic floating window technique into the interactive domain enabling the player to position a virtual window in space. Interactively changing the position, size, and the 3D rotation of the virtual window, objects can be made to 'break the mask' dramatically enhancing the stereoscopic effect. By demonstrating that solutions from the film industry can be extended into the interactive space, it is our hope that this initiates further discussion in the game development community to strengthen their story-telling mechanisms in stereoscopic 3D games.

  16. A 3-D mixed-reality system for stereoscopic visualization of medical dataset.

    PubMed

    Ferrari, Vincenzo; Megali, Giuseppe; Troia, Elena; Pietrabissa, Andrea; Mosca, Franco

    2009-11-01

    We developed a simple, light, and cheap 3-D visualization device based on mixed reality that can be used by physicians to see preoperative radiological exams in a natural way. The system allows the user to see stereoscopic "augmented images," which are created by mixing 3-D virtual models of anatomies obtained by processing preoperative volumetric radiological images (computed tomography or MRI) with real patient live images, grabbed by means of cameras. The interface of the system consists of a head-mounted display equipped with two high-definition cameras. Cameras are mounted in correspondence of the user's eyes and allow one to grab live images of the patient with the same point of view of the user. The system does not use any external tracker to detect movements of the user or the patient. The movements of the user's head and the alignment of virtual patient with the real one are done using machine vision methods applied on pairs of live images. Experimental results, concerning frame rate and alignment precision between virtual and real patient, demonstrate that machine vision methods used for localization are appropriate for the specific application and that systems based on stereoscopic mixed reality are feasible and can be proficiently adopted in clinical practice.

  17. Interlopers 3D: experiences designing a stereoscopic game

    NASA Astrophysics Data System (ADS)

    Weaver, James; Holliman, Nicolas S.

    2014-03-01

    Background In recent years 3D-enabled televisions, VR headsets and computer displays have become more readily available in the home. This presents an opportunity for game designers to explore new stereoscopic game mechanics and techniques that have previously been unavailable in monocular gaming. Aims To investigate the visual cues that are present in binocular and monocular vision, identifying which are relevant when gaming using a stereoscopic display. To implement a game whose mechanics are so reliant on binocular cues that the game becomes impossible or at least very difficult to play in non-stereoscopic mode. Method A stereoscopic 3D game was developed whose objective was to shoot down advancing enemies (the Interlopers) before they reached their destination. Scoring highly required players to make accurate depth judgments and target the closest enemies first. A group of twenty participants played both a basic and advanced version of the game in both monoscopic 2D and stereoscopic 3D. Results The results show that in both the basic and advanced game participants achieved higher scores when playing in stereoscopic 3D. The advanced game showed that by disrupting the depth from motion cue the game became more difficult in monoscopic 2D. Results also show a certain amount of learning taking place over the course of the experiment, meaning that players were able to score higher and finish the game faster over the course of the experiment. Conclusions Although the game was not impossible to play in monoscopic 2D, participants results show that it put them at a significant disadvantage when compared to playing in stereoscopic 3D.

  18. Using mental rotation to evaluate the benefits of stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Aitsiselmi, Y.; Holliman, N. S.

    2009-02-01

    Context: The idea behind stereoscopic displays is to create the illusion of depth and this concept could have many practical applications. A common spatial ability test involves mental rotation. Therefore a mental rotation task should be easier if being undertaken on a stereoscopic screen. Aim: The aim of this project is to evaluate stereoscopic displays (3D screen) and to assess whether they are better for performing a certain task than over a 2D display. A secondary aim was to perform a similar study but replicating the conditions of using a stereoscopic mobile phone screen. Method: We devised a spatial ability test involving a mental rotation task that participants were asked to complete on either a 3D or 2D screen. We also design a similar task to simulate the experience on a stereoscopic cell phone. The participants' error rate and response times were recorded. Using statistical analysis, we then compared the error rate and response times of the groups to see if there were any significant differences. Results: We found that the participants got better scores if they were doing the task on a stereoscopic screen as opposed to a 2D screen. However there was no statistically significant difference in the time it took them to complete the task. We also found similar results for 3D cell phone display condition. Conclusions: The results show that the extra depth information given by a stereoscopic display makes it easier to mentally rotate a shape as depth cues are readily available. These results could have many useful implications to certain industries.

  19. Binocular Coordination: Reading Stereoscopic Sentences in Depth

    PubMed Central

    Schotter, Elizabeth R.; Blythe, Hazel I.; Kirkby, Julie A.; Rayner, Keith; Holliman, Nicolas S.; Liversedge, Simon P.

    2012-01-01

    The present study employs a stereoscopic manipulation to present sentences in three dimensions to subjects as they read for comprehension. Subjects read sentences with (a) no depth cues, (b) a monocular depth cue that implied the sentence loomed out of the screen (i.e., increasing retinal size), (c) congruent monocular and binocular (retinal disparity) depth cues (i.e., both implied the sentence loomed out of the screen) and (d) incongruent monocular and binocular depth cues (i.e., the monocular cue implied the sentence loomed out of the screen and the binocular cue implied it receded behind the screen). Reading efficiency was mostly unaffected, suggesting that reading in three dimensions is similar to reading in two dimensions. Importantly, fixation disparity was driven by retinal disparity; fixations were significantly more crossed as readers progressed through the sentence in the congruent condition and significantly more uncrossed in the incongruent condition. We conclude that disparity depth cues are used on-line to drive binocular coordination during reading. PMID:22558174

  20. Binocular coordination: reading stereoscopic sentences in depth.

    PubMed

    Schotter, Elizabeth R; Blythe, Hazel I; Kirkby, Julie A; Rayner, Keith; Holliman, Nicolas S; Liversedge, Simon P

    2012-01-01

    The present study employs a stereoscopic manipulation to present sentences in three dimensions to subjects as they read for comprehension. Subjects read sentences with (a) no depth cues, (b) a monocular depth cue that implied the sentence loomed out of the screen (i.e., increasing retinal size), (c) congruent monocular and binocular (retinal disparity) depth cues (i.e., both implied the sentence loomed out of the screen) and (d) incongruent monocular and binocular depth cues (i.e., the monocular cue implied the sentence loomed out of the screen and the binocular cue implied it receded behind the screen). Reading efficiency was mostly unaffected, suggesting that reading in three dimensions is similar to reading in two dimensions. Importantly, fixation disparity was driven by retinal disparity; fixations were significantly more crossed as readers progressed through the sentence in the congruent condition and significantly more uncrossed in the incongruent condition. We conclude that disparity depth cues are used on-line to drive binocular coordination during reading.

  1. What is stereoscopic vision good for?

    NASA Astrophysics Data System (ADS)

    Read, Jenny C. A.

    2015-03-01

    Stereo vision is a resource-intensive process. Nevertheless, it has evolved in many animals including mammals, birds, amphibians and insects. It must therefore convey significant fitness benefits. It is often assumed that the main benefit is improved accuracy of depth judgments, but camouflage breaking may be as important, particularly in predatory animals. In humans, for the last 150 years, stereo vision has been turned to a new use: helping us reproduce visual reality for artistic purposes. By recreating the different views of a scene seen by the two eyes, stereo achieves unprecedented levels of realism. However, it also has some unexpected effects on viewer experience. The disruption of established mechanisms for interpreting pictures may be one reason why some viewers find stereoscopic content disturbing. Stereo vision also has uses in ophthalmology. Clinical stereoacuity tests are used in the management of conditions such as strabismus and amblyopia as well as vision screening. Stereoacuity can reveal the effectiveness of therapy and even predict long-term outcomes post surgery. Yet current clinical stereo tests fall far short of the accuracy and precision achievable in the lab. At Newcastle University, we are exploiting the recent availability of autostereo 3D tablet computers to design a clinical stereotest app in the form of a game suitable for young children. Our goal is to enable quick, accurate and precise stereoacuity measures which will enable clinicians to obtain better outcomes for children with visual disorders.

  2. Field-Sequential Electronic Stereoscopic Projector

    NASA Astrophysics Data System (ADS)

    Lipton, Lenny

    1989-07-01

    Culminating a research and development project spanning many years, StereoGraphics Corporation has succeeded in bringing to market the first field-sequential electronic stereoscopic projector. The product is based on a modification of Electrohome and Barco projectors. Our design goal was to produce a projector capable of displaying an image on a six-foot (or larger) diagonal screen for an audience of 50 or 60 people, or for an individual using a simulator. A second goal was to produce an image that required only passive polarizing glasses rather than powered, tethered visors. Two major design challenges posed themselves. First, it was necessary to create an electro-optical modulator which could switch the characteristic of polarized light at field rate, and second, it was necessary to produce a bright green CRT with short persistence to prevent crosstalk between left and right fields. To solve the first problem, development was undertaken to produce the required electro-optical modulator. The second problem was solved with the help of a vendor specializing in high performance CRT's.

  3. Low-Cost Instant Surveillance System

    NASA Astrophysics Data System (ADS)

    Prokoski, Francine J.

    1983-06-01

    A low-cost, battery-operated surveillance system was developed for use in international nuclear safeguards. The resulting system utilizes components of the commercial Polavision instant movie system to provide single-frame color or black/white images which are automatically developed and displayed by a portable Polavision Player whenever it is desired to stop and view the film. The system is designed for long-term unattended use, triggered by a timer or other input signal. To provide positive assurance of continuing operation, a self-diagnostic module was designed to detect the most common failure modes and transmit real-time status data to a remote location. The resulting system provides a low-cost surveillance capability which may be useful in various law enforcement applications.

  4. The aqueous stability of a Mars salt analog: Instant Mars

    NASA Astrophysics Data System (ADS)

    Nuding, D. L.; Davis, R. D.; Gough, R. V.; Tolbert, M. A.

    2015-03-01

    Due to their stability in low-temperature conditions, aqueous salt solutions are the favored explanation for potential fluid features observed on present-day Mars. A salt analog was developed to closely match the individual cation and anion concentrations at the Phoenix landing site as reported by the Wet Chemistry Laboratory instrument. "Instant Mars" closely replicates correct relative concentrations of magnesium, calcium, potassium, sodium, perchlorate, chloride, and sulfate ions. A Raman microscope equipped with an environmental cellprobed liquid water uptake and loss by Instant Mars particles in a Mars relevant temperature and relative humidity (RH) environment. Our experiments reveal that Instant Mars particles can form stable, aqueous solutions starting at 56 ± 5% RH between 235 K and 243 K and persist as a metastable, aqueous solution at or above 13 ± 5% RH. Particle levitation using an optical trap examined the phase state and morphology of suspended Instant Mars particles exposed to changing water vapor conditions at room temperature. Levitation experiments indicate that water uptake began at 42 ± 8% RH for Instant Mars particles at 293 K. As RH is decreased at 293 K, the aqueous Instant Mars particles transition into a crystalline solid at 18 ± 7% RH. These combined results demonstrate that Instant Mars can take up water vapor from the surrounding environment and transition into a stable, aqueous solution. Furthermore, this aqueous Instant Mars solution can persist as a metastable, supersaturated solution in low-RH conditions.

  5. Lol: New Language and Spelling in Instant Messaging

    ERIC Educational Resources Information Center

    Varnhagen, Connie K.; McFall, G. Peggy; Pugh, Nicole; Routledge, Lisa; Sumida-MacDonald, Heather; Kwong, Trudy E.

    2010-01-01

    Written communication in instant messaging, text messaging, chat, and other forms of electronic communication appears to have generated a "new language" of abbreviations, acronyms, word combinations, and punctuation. In this naturalistic study, adolescents collected their instant messaging conversations for a 1-week period and then completed a…

  6. Lol: New Language and Spelling in Instant Messaging

    ERIC Educational Resources Information Center

    Varnhagen, Connie K.; McFall, G. Peggy; Pugh, Nicole; Routledge, Lisa; Sumida-MacDonald, Heather; Kwong, Trudy E.

    2010-01-01

    Written communication in instant messaging, text messaging, chat, and other forms of electronic communication appears to have generated a "new language" of abbreviations, acronyms, word combinations, and punctuation. In this naturalistic study, adolescents collected their instant messaging conversations for a 1-week period and then completed a…

  7. Classifying EEG Signals during Stereoscopic Visualization to Estimate Visual Comfort

    PubMed Central

    Frey, Jérémy; Appriou, Aurélien; Lotte, Fabien; Hachet, Martin

    2016-01-01

    With stereoscopic displays a sensation of depth that is too strong could impede visual comfort and may result in fatigue or pain. We used Electroencephalography (EEG) to develop a novel brain-computer interface that monitors users' states in order to reduce visual strain. We present the first system that discriminates comfortable conditions from uncomfortable ones during stereoscopic vision using EEG. In particular, we show that either changes in event-related potentials' (ERPs) amplitudes or changes in EEG oscillations power following stereoscopic objects presentation can be used to estimate visual comfort. Our system reacts within 1 s to depth variations, achieving 63% accuracy on average (up to 76%) and 74% on average when 7 consecutive variations are measured (up to 93%). Performances are stable (≈62.5%) when a simplified signal processing is used to simulate online analyses or when the number of EEG channels is lessened. This study could lead to adaptive systems that automatically suit stereoscopic displays to users and viewing conditions. For example, it could be possible to match the stereoscopic effect with users' state by modifying the overlap of left and right images according to the classifier output. PMID:26819580

  8. Classifying EEG Signals during Stereoscopic Visualization to Estimate Visual Comfort.

    PubMed

    Frey, Jérémy; Appriou, Aurélien; Lotte, Fabien; Hachet, Martin

    2016-01-01

    With stereoscopic displays a sensation of depth that is too strong could impede visual comfort and may result in fatigue or pain. We used Electroencephalography (EEG) to develop a novel brain-computer interface that monitors users' states in order to reduce visual strain. We present the first system that discriminates comfortable conditions from uncomfortable ones during stereoscopic vision using EEG. In particular, we show that either changes in event-related potentials' (ERPs) amplitudes or changes in EEG oscillations power following stereoscopic objects presentation can be used to estimate visual comfort. Our system reacts within 1 s to depth variations, achieving 63% accuracy on average (up to 76%) and 74% on average when 7 consecutive variations are measured (up to 93%). Performances are stable (≈62.5%) when a simplified signal processing is used to simulate online analyses or when the number of EEG channels is lessened. This study could lead to adaptive systems that automatically suit stereoscopic displays to users and viewing conditions. For example, it could be possible to match the stereoscopic effect with users' state by modifying the overlap of left and right images according to the classifier output.

  9. Stereoscopic system for measuring particle trajectories past an underwater model

    NASA Astrophysics Data System (ADS)

    Liu, H.-T.; Weissman, Michael A.; White, Gary B.; Miner, G. E.; Gustafson, William T.

    1994-04-01

    A stereoscopic system was developed that integrates hardware and software components for image acquisition, digitization, processing, display, and measurements. The model-induced trajectories of nearly neutrally buoyant fluorescent particles, illuminated with a 15-W pulsed copper vapor laser, are tracked in a towing tank by stereoscopic time-lapse photography using two 35-mm cameras positioned at a 90-degree angle from the top and the side. A C program, HI, drives two data I/O boards hosted in a PC to set up the run parameters, control the operations of the laser and camera shutters, and acquire the stereo images. The photographic records are digitized and processed to derive the centroids of reference marks and particle images. The centroids are then fed into a Windows-based program, Track/3D, to perform image correlation, correction for image distortion, stereo conversion, stereoscopic display, and measurements. The display module incorporates a graphics library that drives a stereoscopic display adapter attached to a monitor; the stereogram must be viewed with polarizing glasses. Functions are available for image translation, rotation, zooming, and on- screen measurements. The velocity and acceleration components of the 3-D flow field induced by the model are derived from the trajectories, serving as a basis for whole-field stereoscopic quantitative flow visualization.

  10. Production and evaluation of stereoscopic video presentation in surgical training

    NASA Astrophysics Data System (ADS)

    Ilgner, Justus; Kawai, Takashi; Westhofen, Martin; Shibata, Takashi

    2004-05-01

    Stereoscopic video teaching can facilitate understanding for current minimally-invasive operative techniques. This project was created to set up a digital stereoscopic teaching environment for training of ENT residents and medical students. We recorded three ENT operative procedures (tympanoplasty, paranasal sinus operation and laser chordectomy) at the University Hospital Aachen. The material was edited stereoscopically at the Waseda University and converted into a streaming 3-D video format, which does not depend on PAL or NTSC signal standards. Video clips were evaluated by 5 ENT specialists and 11 residents in single sessions on an LCD monitor (8) and a CRT monitor (8). Emphasis was laid on depth perception, visual fatigue and time to achieve stereoscopic impression. Qualitative results were recorded on a visual analogue scale, ranging from 1 (excellent) to 5 (bad). The overall impression was rated 2,06 to 3,13 in the LCD group and 2,0 to 2,62 in the CRT group. The depth impression was rated 1,63 to 2,88 (LCD) and 1,63 to 2,25 (CRT). Stereoscopic video teaching was regarded as useful in ENT training by all participants. Further points for evaluation will be the quantification of depth information as well as the information gain in teaching junior colleagues.

  11. Interactive 2D to 3D stereoscopic image synthesis

    NASA Astrophysics Data System (ADS)

    Feldman, Mark H.; Lipton, Lenny

    2005-03-01

    Advances in stereoscopic display technologies, graphic card devices, and digital imaging algorithms have opened up new possibilities in synthesizing stereoscopic images. The power of today"s DirectX/OpenGL optimized graphics cards together with adapting new and creative imaging tools found in software products such as Adobe Photoshop, provide a powerful environment for converting planar drawings and photographs into stereoscopic images. The basis for such a creative process is the focus of this paper. This article presents a novel technique, which uses advanced imaging features and custom Windows-based software that utilizes the Direct X 9 API to provide the user with an interactive stereo image synthesizer. By creating an accurate and interactive world scene with moveable and flexible depth map altered textured surfaces, perspective stereoscopic cameras with both visible frustums and zero parallax planes, a user can precisely model a virtual three-dimensional representation of a real-world scene. Current versions of Adobe Photoshop provide a creative user with a rich assortment of tools needed to highlight elements of a 2D image, simulate hidden areas, and creatively shape them for a 3D scene representation. The technique described has been implemented as a Photoshop plug-in and thus allows for a seamless transition of these 2D image elements into 3D surfaces, which are subsequently rendered to create stereoscopic views.

  12. Effects of stereoscopic presentation on visually induced motion sickness

    NASA Astrophysics Data System (ADS)

    Ujike, Hiroyasu; Watanabe, Hiroshi

    2011-03-01

    The present study investigates whether VIMS, which can be induced in 2D images, is affected by stereoscopic presentation. To do this, we conducted an experiment to measure the effects psychologically and physiologically. Visual stimulus was computer graphics that simulates traveling along streets with additional pitch and roll motion for 10 minutes. The stimulus were presented as either stereoscopic, "3D", images or "2D" images. Before/after and during each trial, psychological and physiological measurements for biomedical effects were conducted. As results, psychological measurements indicate effects of stereoscopic presentations on VIMS. First, subjective score of comfort level measured every one minute significantly decreased to uncomfortable level in the 3D than in the 2D condition. Second, subscore of "Nausea" of Simulator Sickness Questionnaire significantly higher in the 3D than in the 2D condition, while the other subscores and the total score also showed the similar tendency. Moreover, physiological measurements also indicate effects of 3D presentations on VIMS. The LF/HF ratio, which is the index of sympathetic nerve activity, clearly increased more in the 3D than in the 2D condition. We conclude that stereoscopic presentation enhances biomedical effects of VIMS. We speculate that stereoscopic images can be efficient reference of spatial orientation.

  13. The Stereoscopic Anisotropy Develops During Childhood

    PubMed Central

    Serrano-Pedraza, Ignacio; Herbert, William; Villa-Laso, Laura; Widdall, Michael; Vancleef, Kathleen; Read, Jenny C. A.

    2016-01-01

    Purpose Human vision has a puzzling stereoscopic anisotropy: horizontal depth corrugations are easier to detect than vertical depth corrugations. To date, little is known about the function or the underlying mechanism responsible for this anisotropy. Here, we aim to find out whether this anisotropy is independent of age. To answer this, we compare detection thresholds for horizontal and vertical depth corrugations as a function of age. Methods The depth corrugations were defined solely by the horizontal disparity of random dot patterns. The disparities depicted a horizontal or vertical sinusoidal depth corrugation of spatial frequency 0.1 cyc/deg. Detection thresholds were obtained using Bayesian adaptive staircases from a total of 159 subjects aged from 3 to 73 years. For each participant we computed the anisotropy index, defined as the log10-ratio of the detection threshold for vertical corrugations divided by that for horizontal. Results Anisotropy index was highly variable between individuals but was positive in 87% of the participants. There was a significant correlation between anisotropy index and log-age (r = 0.21, P = 0.008) mainly driven by a significant difference between children and adults. In 67 children aged 3 to 13 years, the mean anisotropy index was 0.34 ± 0.38 (mean ± SD, meaning that vertical thresholds were on average 2.2 times the horizontal ones), compared with 0.59 ± 0.55 in 84 adults aged 18 to 73 years (vertical 3.9 times horizontal). This was mainly driven by a decline in the sensitivity to vertical corrugations. Children had poorer stereoacuity than adults, but had similar sensitivity to adults for horizontal corrugations and were actually more sensitive than adults to vertical corrugations. Conclusions The fact that adults show stronger stereo anisotropy than children raises the possibility that visual experience plays a critical role in developing and strengthening the stereo anisotropy. PMID:26962692

  14. Contrast sensitivity function in stereoscopic viewing of Gabor patches on a medical polarized three-dimensional stereoscopic display

    NASA Astrophysics Data System (ADS)

    Rousson, Johanna; Haar, Jérémy; Santal, Sarah; Kumcu, Asli; Platiša, Ljiljana; Piepers, Bastian; Kimpe, Tom; Philips, Wilfried

    2016-03-01

    While three-dimensional (3-D) imaging systems are entering hospitals, no study to date has explored the luminance calibration needs of 3-D stereoscopic diagnostic displays and if they differ from two-dimensional (2-D) displays. Since medical display calibration incorporates the human contrast sensitivity function (CSF), we first assessed the 2-D CSF for benchmarking and then examined the impact of two image parameters on the 3-D stereoscopic CSF: (1) five depth plane (DP) positions (between DP: -171 and DP: 2853 mm), and (2) three 3-D inclinations (0 deg, 45 deg, and 60 deg around the horizontal axis of a DP). Stimuli were stereoscopic images of a vertically oriented 2-D Gabor patch at one of seven frequencies ranging from 0.4 to 10 cycles/deg. CSFs were measured for seven to nine human observers with a staircase procedure. The results indicate that the 2-D CSF model remains valid for a 3-D stereoscopic display regardless of the amount of disparity between the stereo images. We also found that the 3-D CSF at DP≠0 does not differ from the 3-D CSF at DP=0 for DPs and disparities which allow effortless binocular fusion. Therefore, the existing 2-D medical luminance calibration algorithm remains an appropriate tool for calibrating polarized stereoscopic medical displays.

  15. Large Stereoscopic LED Display by Use of a Parallax Barrier

    NASA Astrophysics Data System (ADS)

    Yamamoto, Hirotsugu; Hayasaki, Yoshio; Nishida, Nobuo

    Since the development of high-brightness blue and green LEDs, the use of outdoor commercial LED displays has been increasing. Because of their high-brightness, good visibility, and long-term durability, LED displays are a preferred technology for outdoor installations such as stadiums, street advertising, and billboards. This chapter deals with a large stereoscopic full-color LED display using a parallax barrier. We discuss optimization of viewing areas, which depend on LED arrangements. Enlarged viewing areas have been demonstrated by using a three-in-one chip LED panel that has wider black regions than ordinary LED lamp cluster panels. We have developed a real-time system to measure a viewer's position and investigated the movements of viewers who watch different designs of stereoscopic LED displays, including conventional designs and designs to eliminate pseudoscopic viewing areas. The design of parallax barrier for plural viewers was utilized for a 140-inch stereoscopic LED display.

  16. Automatic Correction of Hand Pointing in Stereoscopic Depth

    PubMed Central

    Song, Yalin; Sun, Yaoru; Zeng, Jinhua; Wang, Fang

    2014-01-01

    In order to examine whether stereoscopic depth information could drive fast automatic correction of hand pointing, an experiment was designed in a 3D visual environment in which participants were asked to point to a target at different stereoscopic depths as quickly and accurately as possible within a limited time window (≤300 ms). The experiment consisted of two tasks: “depthGO” in which participants were asked to point to the new target position if the target jumped, and “depthSTOP” in which participants were instructed to abort their ongoing movements after the target jumped. The depth jump was designed to occur in 20% of the trials in both tasks. Results showed that fast automatic correction of hand movements could be driven by stereoscopic depth to occur in as early as 190 ms. PMID:25501878

  17. A post-alignment method for stereoscopic movie

    NASA Astrophysics Data System (ADS)

    Du, Xin; Chen, Xiao-yu; Bhaskaran, Vasudev; Ling, Fan; Zhu, Yun-fang; Shen, Hui-liang

    2013-09-01

    In this paper, we propose a novel post-alignment method. The method is both simple and effective for stereo video postproduction. A low-distortion algorithm for rectifying the epipolar lines is first introduced. Unlike traditional methods, which map the epipoles to (1,0,0) T directly, our method conducts it in two steps: 1) mapping the epipoles to points at infinity; 2) aligning the epipolar lines with x-axis. More specifically, by taking advantage of that commonly available stereoscopic movies are nearly aligned, our method keeps one of the stereo images unchanged, and the rectification is only applied to the other image. Besides epipolar non-parallel distortions, disparity distortion is also an important issue to consider for the stereoscopic movie. We propose a new constraint for stereoscopic video alignment such that the variations of disparities is also minimized. Experimental results have demonstrated that our method obtains better visual effect than the state-of-the-art methods.

  18. A comparison of food and nutrient intake between instant noodle consumers and non-instant noodle consumers in Korean adults.

    PubMed

    Park, Juyeon; Lee, Jung-Sug; Jang, Young Ai; Chung, Hae Rang; Kim, Jeongseon

    2011-10-01

    Instant noodles are widely consumed in Asian countries. The Korean population consumed the largest quantity of instant noodles in the world in 2008. However, few studies have investigated the relationship between instant noodles and nutritional status in Koreans. The objective of this study was to examine the association between instant noodle consumption and food and nutrient intake in Korean adults. We used dietary data of 6,440 subjects aged 20 years and older who participated in the Korean National Health and Nutrition Examination Survey III. The average age of the instant noodle consumers (INC) was 36.2 and that of the non-instant noodle consumers (non-INC) was 44.9; men consumed more instant noodles than women (P < 0.001). With the exception of cereals and grain products, legumes, seaweeds, eggs, and milk and dairy products, INC consumed significantly fewer potatoes and starches, sugars, seeds and nuts, vegetables, mushrooms, fruits, seasonings, beverages, meats, fishes, and oils and fats compared with those in the non-INC group. The INC group showed significantly higher nutrient intake of energy, fat, sodium, thiamine, and riboflavin; however, the INC group showed a significantly lower intake of protein, calcium, phosphorus, iron, potassium, vitamin A, niacin, and vitamin C compared with those in the non-INC group. This study revealed that consuming instant noodles may lead to excessive intake of energy, fats, and sodium but may also cause increased intake of thiamine and riboflavin. Therefore, nutritional education helping adults to choose a balanced meal while consuming instant noodles should be implemented. Additionally, instant noodle manufacturers should consider nutritional aspects when developing new products.

  19. A comparison of food and nutrient intake between instant noodle consumers and non-instant noodle consumers in Korean adults

    PubMed Central

    Park, Juyeon; Lee, Jung-Sug; Jang, Young Ai; Chung, Hae Rang

    2011-01-01

    Instant noodles are widely consumed in Asian countries. The Korean population consumed the largest quantity of instant noodles in the world in 2008. However, few studies have investigated the relationship between instant noodles and nutritional status in Koreans. The objective of this study was to examine the association between instant noodle consumption and food and nutrient intake in Korean adults. We used dietary data of 6,440 subjects aged 20 years and older who participated in the Korean National Health and Nutrition Examination Survey III. The average age of the instant noodle consumers (INC) was 36.2 and that of the non-instant noodle consumers (non-INC) was 44.9; men consumed more instant noodles than women (P < 0.001). With the exception of cereals and grain products, legumes, seaweeds, eggs, and milk and dairy products, INC consumed significantly fewer potatoes and starches, sugars, seeds and nuts, vegetables, mushrooms, fruits, seasonings, beverages, meats, fishes, and oils and fats compared with those in the non-INC group. The INC group showed significantly higher nutrient intake of energy, fat, sodium, thiamine, and riboflavin; however, the INC group showed a significantly lower intake of protein, calcium, phosphorus, iron, potassium, vitamin A, niacin, and vitamin C compared with those in the non-INC group. This study revealed that consuming instant noodles may lead to excessive intake of energy, fats, and sodium but may also cause increased intake of thiamine and riboflavin. Therefore, nutritional education helping adults to choose a balanced meal while consuming instant noodles should be implemented. Additionally, instant noodle manufacturers should consider nutritional aspects when developing new products. PMID:22125682

  20. Astronomical imagination and stereoscopic vision: conscious and unconscious processing of visual data.

    NASA Astrophysics Data System (ADS)

    Hill, L. C., Jr.

    Analogies between unconscious visual processing of stereoscopic vision and common astronomical techniques are highlighted. An attempt to exploit some of these powerful intuitive stereoscopic processes is reported. Computer-generated stereograms have been constructed to provide students with stereoscopic views of important astronomical relationships. Some first stereograms are presented and attendant successes, difficulties and prospects are sketched.

  1. Stereoscopic Perception of Women in Real and Virtual Environments: A Study towards Educational Neuroscience

    ERIC Educational Resources Information Center

    Zacharis, Georgios S.; Mikropoulos, Tassos A.; Priovolou, Chryssi

    2013-01-01

    Previous studies report the involvement of specific brain activation in stereoscopic vision and the perception of depth information. This work presents the first comparative results of adult women on the effects of stereoscopic perception in three different static environments; a real, a two dimensional (2D) and a stereoscopic three dimensional…

  2. Cosmic cookery: making a stereoscopic 3D animated movie

    NASA Astrophysics Data System (ADS)

    Holliman, Nick; Baugh, Carlton; Frenk, Carlos; Jenkins, Adrian; Froner, Barbara; Hassaine, Djamel; Helly, John; Metcalfe, Nigel; Okamoto, Takashi

    2006-02-01

    This paper describes our experience making a short stereoscopic movie visualizing the development of structure in the universe during the 13.7 billion years from the Big Bang to the present day. Aimed at a general audience for the Royal Society's 2005 Summer Science Exhibition, the movie illustrates how the latest cosmological theories based on dark matter and dark energy are capable of producing structures as complex as spiral galaxies and allows the viewer to directly compare observations from the real universe with theoretical results. 3D is an inherent feature of the cosmology data sets and stereoscopic visualization provides a natural way to present the images to the viewer, in addition to allowing researchers to visualize these vast, complex data sets. The presentation of the movie used passive, linearly polarized projection onto a 2m wide screen but it was also required to playback on a Sharp RD3D display and in anaglyph projection at venues without dedicated stereoscopic display equipment. Additionally lenticular prints were made from key images in the movie. We discuss the following technical challenges during the stereoscopic production process; 1) Controlling the depth presentation, 2) Editing the stereoscopic sequences, 3) Generating compressed movies in display specific formats. We conclude that the generation of high quality stereoscopic movie content using desktop tools and equipment is feasible. This does require careful quality control and manual intervention but we believe these overheads are worthwhile when presenting inherently 3D data as the result is significantly increased impact and better understanding of complex 3D scenes.

  3. Case study: using a stereoscopic display for mission planning

    NASA Astrophysics Data System (ADS)

    Kleiber, Michael; Winkelholz, Carsten

    2009-02-01

    This paper reports on the results of a study investigating the benefits of using an autostereoscopic display in the training targeting process of the Germain Air Force. The study examined how stereoscopic 3D visualizations can help to improve flight path planning and the preparation of a mission in general. An autostereoscopic display was used because it allows the operator to perceive the stereoscopic images without shutter glasses which facilitates the integration into a workplace with conventional 2D monitors and arbitrary lighting conditions.

  4. Stereoscopic virtual reality presurgical planning for cerebrospinal otorrhea.

    PubMed

    Shen, Ming; Zhang, Xiao-Luo; Yang, De-Lin; Wu, Jin-Song

    2010-07-01

    We present a complicated case of spontaneous cerebrospinal otorrhea, which had not been cured despite undergoing 5 surgical interventions in the past. The disability to identify the location of the fistula was the main crux of the past failures. On this occasion, stereoscopic virtual reality presurgical planning was applied to identify the exact location of the fistula and a surgical simulation was performed, and was later confirmed during the actual operation. Interactive manipulation in a stereoscopic virtual environment makes the decision making process easier in the treatment of cerebrospinal otorrhea.

  5. The Role of Amodal Surface Completion in Stereoscopic Transparency

    PubMed Central

    Anderson, Barton L.; Schmid, Alexandra C.

    2012-01-01

    Previous work has shown that the visual system can decompose stereoscopic textures into percepts of inhomogeneous transparency. We investigate whether this form of layered image decomposition is shaped by constraints on amodal surface completion. We report a series of experiments that demonstrate that stereoscopic depth differences are easier to discriminate when the stereo images generate a coherent percept of surface color, than when images require amodally integrating a series of color changes into a coherent surface. Our results provide further evidence for the intimate link between the segmentation processes that occur in conditions of transparency and occlusion, and the interpolation processes involved in the formation of amodally completed surfaces. PMID:23060829

  6. Construction of an instant structured illumination microscope

    PubMed Central

    Curd, Alistair; Cleasby, Alexa; Makowska, Katarzyna; York, Andrew; Shroff, Hari; Peckham, Michelle

    2015-01-01

    A challenge in biological imaging is to capture high-resolution images at fast frame rates in live cells. The “instant structured illumination microscope” (iSIM) is a system designed for this purpose. Similarly to standard structured illumination microscopy (SIM), an iSIM provides a twofold improvement over widefield microscopy, in x, y and z, but also allows much faster image acquisition, with real-time display of super-resolution images. The assembly of an iSIM is reasonably complex, involving the combination and alignment of many optical components, including three micro-optics arrays (two lenslet arrays and an array of pinholes, all with a pitch of 222 μm) and a double-sided scanning mirror. In addition, a number of electronic components must be correctly controlled. Construction of the system is therefore not trivial, but is highly desirable, particularly for live-cell imaging. We report, and provide instructions for, the construction of an iSIM, including minor modifications to a previous design in both hardware and software. The final instrument allows us to rapidly acquire fluorescence images at rates faster than 100 fps, with approximately twofold improvement in resolution in both x–y and z; sub-diffractive biological features have an apparent size (full width at half maximum) of 145 nm (lateral) and 320 nm (axial), using a 1.49 NA objective and 488 nm excitation. PMID:26210400

  7. Construction of an instant structured illumination microscope.

    PubMed

    Curd, Alistair; Cleasby, Alexa; Makowska, Katarzyna; York, Andrew; Shroff, Hari; Peckham, Michelle

    2015-10-15

    A challenge in biological imaging is to capture high-resolution images at fast frame rates in live cells. The "instant structured illumination microscope" (iSIM) is a system designed for this purpose. Similarly to standard structured illumination microscopy (SIM), an iSIM provides a twofold improvement over widefield microscopy, in x, y and z, but also allows much faster image acquisition, with real-time display of super-resolution images. The assembly of an iSIM is reasonably complex, involving the combination and alignment of many optical components, including three micro-optics arrays (two lenslet arrays and an array of pinholes, all with a pitch of 222 μm) and a double-sided scanning mirror. In addition, a number of electronic components must be correctly controlled. Construction of the system is therefore not trivial, but is highly desirable, particularly for live-cell imaging. We report, and provide instructions for, the construction of an iSIM, including minor modifications to a previous design in both hardware and software. The final instrument allows us to rapidly acquire fluorescence images at rates faster than 100 fps, with approximately twofold improvement in resolution in both x-y and z; sub-diffractive biological features have an apparent size (full width at half maximum) of 145 nm (lateral) and 320 nm (axial), using a 1.49 NA objective and 488 nm excitation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  8. 3D Stereoscopic Visualization of Fenestrated Stent Grafts

    SciTech Connect

    Sun Zhonghua; Squelch, Andrew; Bartlett, Andrew; Cunningham, Kylie; Lawrence-Brown, Michael

    2009-09-15

    The purpose of this study was to present a technique of stereoscopic visualization in the evaluation of patients with abdominal aortic aneurysm treated with fenestrated stent grafts compared with conventional 2D visualizations. Two patients with abdominal aortic aneurysm undergoing fenestrated stent grafting were selected for inclusion in the study. Conventional 2D views including axial, multiplanar reformation, maximum-intensity projection, and volume rendering and 3D stereoscopic visualizations were assessed by two experienced reviewers independently with regard to the treatment outcomes of fenestrated repair. Interobserver agreement was assessed with Kendall's W statistic. Multiplanar reformation and maximum-intensity projection visualizations were scored the highest in the evaluation of parameters related to the fenestrated stent grafting, while 3D stereoscopic visualization was scored as valuable in the evaluation of appearance (any distortions) of the fenestrated stent. Volume rendering was found to play a limited role in the follow-up of fenestrated stent grafting. 3D stereoscopic visualization adds additional information that assists endovascular specialists to identify any distortions of the fenestrated stents when compared with 2D visualizations.

  9. Stereoscopic layout of a perspective flight guidance display

    NASA Astrophysics Data System (ADS)

    Hammer, Matthias; Muecke, Stephan K. M.; Mayer, Udo

    1997-05-01

    Analyses of aviation accidents ascribe about 75% of all incidents to human (pilot) behavior. A strong effort is being made to improve ergonomic cockpit layout, because of dramatic changes in the airspace structure, the increase in air traffic, and larger aircraft. One part of an interdisciplinary research project investigates the potential of stereoscopic flight-guidance displays in order to improve pilots' situation awareness. This experimental approach, which aims to research and apply ergonomic design recommendations for stereoscopic flight displays, is based upon a new type of perspective flight-guidance display. The examination of existing research regarding stereoscopic flight displays reveals a lack of basic knowledge, as well as a need for further systematic research into cockpit application. Thus the project contains experiments on different levels of abstraction, ranging from classic parameter experiments to flight simulator tests. Both current knowledge and recent discoveries are applied to superimposed 2-D flight parameters and to real and synthetic 3-D elements, such as a perspective landscape, other airplanes or flight prediction. The stereoscopic layout takes into consideration specific informational needs within different flight phases and is evaluated by means of pilot performance and pilot strain. Selected symbols of the flight guidance display and actual results are presented as examples of the research approach.

  10. Horizontal and vertical disparity, eye position, and stereoscopic slant perception.

    PubMed

    Backus, B T; Banks, M S; van Ee, R; Crowell, J A

    1999-03-01

    The slant of a stereoscopically defined surface cannot be determined solely from horizontal disparities or from derived quantities such as horizontal size ratio (HSR). There are four other signals that, in combination with horizontal disparity, could in principle allow an unambiguous estimate of slant: the vergence and version of the eyes, the vertical size ratio (VSR), and the horizontal gradient of VSR. Another useful signal is provided by perspective slant cues. The determination of perceived slant can be modeled as a weighted combination of three estimates based on those signals: a perspective estimate, a stereoscopic estimate based on HSR and VSR, and a stereoscopic estimate based on HSR and sensed eye position. In a series of experiments, we examined human observers' use of the two stereoscopic means of estimation. Perspective cues were rendered uninformative. We found that VSR and sensed eye position are both used to interpret the measured horizontal disparities. When the two are placed in conflict, the visual system usually gives more weight to VSR. However, when VSR is made difficult to measure by using short stimuli or stimuli composed of vertical lines, the visual system relies on sensed eye position. A model in which the observer's slant estimate is a weighted average of the slant estimate based on HSR and VSR and the one based on HSR and eye position accounted well for the data. The weights varied across viewing conditions because the informativeness of the signals they employ vary from one situation to another.

  11. Stereoscopic display of 3D models for design visualization

    NASA Astrophysics Data System (ADS)

    Gilson, Kevin J.

    2006-02-01

    Advances in display technology and 3D design visualization applications have made real-time stereoscopic visualization of architectural and engineering projects a reality. Parsons Brinkerhoff (PB) is a transportation consulting firm that has used digital visualization tools from their inception and has helped pioneer the application of those tools to large scale infrastructure projects. PB is one of the first Architecture/Engineering/Construction (AEC) firms to implement a CAVE- an immersive presentation environment that includes stereoscopic rear-projection capability. The firm also employs a portable stereoscopic front-projection system, and shutter-glass systems for smaller groups. PB is using commercial real-time 3D applications in combination with traditional 3D modeling programs to visualize and present large AEC projects to planners, clients and decision makers in stereo. These presentations create more immersive and spatially realistic presentations of the proposed designs. This paper will present the basic display tools and applications, and the 3D modeling techniques PB is using to produce interactive stereoscopic content. The paper will discuss several architectural and engineering design visualizations we have produced.

  12. The rendering context for stereoscopic 3D web

    NASA Astrophysics Data System (ADS)

    Chen, Qinshui; Wang, Wenmin; Wang, Ronggang

    2014-03-01

    3D technologies on the Web has been studied for many years, but they are basically monoscopic 3D. With the stereoscopic technology gradually maturing, we are researching to integrate the binocular 3D technology into the Web, creating a stereoscopic 3D browser that will provide users with a brand new experience of human-computer interaction. In this paper, we propose a novel approach to apply stereoscopy technologies to the CSS3 3D Transforms. Under our model, each element can create or participate in a stereoscopic 3D rendering context, in which 3D Transforms such as scaling, translation and rotation, can be applied and be perceived in a truly 3D space. We first discuss the underlying principles of stereoscopy. After that we discuss how these principles can be applied to the Web. A stereoscopic 3D browser with backward compatibility is also created for demonstration purposes. We take advantage of the open-source WebKit project, integrating the 3D display ability into the rendering engine of the web browser. For each 3D web page, our 3D browser will create two slightly different images, each representing the left-eye view and right-eye view, both to be combined on the 3D display to generate the illusion of depth. And as the result turns out, elements can be manipulated in a truly 3D space.

  13. The problem of designing a solar stereoscopic observatory

    NASA Astrophysics Data System (ADS)

    Chebotarev, V.; Grigoryev, V.; Konovalov, V.; Kosenko, V.; Papushev, P.; Uspensky, G.

    This paper presents results derived by exploring the possibilities of creating an interplanetary stereoscopic observatory to invesigate the 3D structure of solar features from granules and spicules to coronal structure. A preliminary study was made of the passive motion of two spacecraft in the vicinity of Lagrangian libration points L 4 and L 4. The version of ballistic scheme of setting-up of the system with a minimal deployment time is considered. For preliminary development of stereoscopic spacecraft the main parameters of scientific payload have been taken: mass - 600 kg, power - 1 kw, summary data - 5 Gbits per day. The chief results of this work are: (i) The stereoscopic observatories can be realized with a complete set of achieable objectives, (ii) launching of spacecraft with the mass 2000 kg into both libration points is possible by using the Soviet rocket-vehicle “Proton” in a time 1.17 year, (iii) Transmission of information from stereoscopic observatory amount 5 Gbit ber day is possible to the ground-based antenna 70 m in diameter and using, aboard the spacecraft's, a transmitting-receiving phase-array antenna of size 5 m.

  14. Development of a 3D stereoscopic flight guidance display

    NASA Astrophysics Data System (ADS)

    Hammer, Matthias; Muecke, Stephan K. M.; Mayer, Udo

    1998-07-01

    As part of an interdisciplinary research project, sponsored by the German Research Community (DFG), the Darmstadt University of Technology investigates the potential offered by stereoscopic flight guidance displays for improving pilot situation awareness. The research aims to formulate ergonomic design recommendations for this type of display. Recent developments in display technology offer new opportunities to improve human-machine interfaces in the cockpit. The utilization of three-dimensional display symbology, as a depiction of three-dimensional sensor or database information, has become an accepted practice in modern enhanced and synthetic vision systems. Nevertheless, the information is depicted on a conventional two-dimensional screen. This can cause problems and errors during the cognitive process of depth perception. The application of stereoscopic technology can add an additional cue which is intuitively seized by the observer. The project concentrates on stereoscopic perspective flight guidance displays as a head down display. The extension to other display types like navigation or head-up display is possible. Because of the complexity of a modern synthetic vision display, the project contains experiments on different levels of abstraction, ranging from classic parameter experiments to flight simulator tests. The stereoscopic layout takes into consideration specific informational needs within different flight phases and is evaluated by means of pilot performance and pilot strain.

  15. Screen of cylindrical lenses produces stereoscopic television pictures

    NASA Technical Reports Server (NTRS)

    Nork, C. L.

    1966-01-01

    Stereoscopic television pictures are produced by placing a colorless, transparent screen of adjacent parallel cylindrical lenses before a raster from two synchronized TV cameras. Alternate frames from alternate cameras are displayed. The viewers sensory perception fuses the two images into one three-dimensional picture.

  16. Optimizing 3D image quality and performance for stereoscopic gaming

    NASA Astrophysics Data System (ADS)

    Flack, Julien; Sanderson, Hugh; Pegg, Steven; Kwok, Simon; Paterson, Daniel

    2009-02-01

    The successful introduction of stereoscopic TV systems, such as Samsung's 3D Ready Plasma, requires high quality 3D content to be commercially available to the consumer. Console and PC games provide the most readily accessible source of high quality 3D content. This paper describes innovative developments in a generic, PC-based game driver architecture that addresses the two key issues affecting 3D gaming: quality and speed. At the heart of the quality issue are the same considerations that studios face producing stereoscopic renders from CG movies: how best to perform the mapping from a geometric CG environment into the stereoscopic display volume. The major difference being that for game drivers this mapping cannot be choreographed by hand but must be automatically calculated in real-time without significant impact on performance. Performance is a critical issue when dealing with gaming. Stereoscopic gaming has traditionally meant rendering the scene twice with the associated performance overhead. An alternative approach is to render the scene from one virtual camera position and use information from the z-buffer to generate a stereo pair using Depth-Image-Based Rendering (DIBR). We analyze this trade-off in more detail and provide some results relating to both 3D image quality and render performance.

  17. Poincare invariant algebra from instant to light-front quantization

    SciTech Connect

    Ji, Chueng-Ryong; Mitchell, Chad

    2001-10-15

    We present the Poincare algebra interpolating between instant and light-front time quantizations. The angular momentum operators satisfying SU(2) algebra are constructed in an arbitrary interpolation angle and shown to be identical to the ordinary angular momentum and Leutwyler-Stern angular momentum in the instant and light-front quantization limits, respectively. The exchange of the dynamical role between the transverse angular mometum and the boost operators is manifest in our newly constructed algebra.

  18. Stereoscopic displays in medical domains: a review of perception and performance effects

    NASA Astrophysics Data System (ADS)

    van Beurden, Maurice H. P. H.; van Hoey, Gert; Hatzakis, Haralambos; Ijsselsteijn, Wijnand A.

    2009-02-01

    In this paper we review empirical studies that investigate performance effects of stereoscopic displays for medical applications. We focus on four distinct application areas: diagnosis, pre-operative planning, minimally invasive surgery (MIS) and training/teaching. For diagnosis, stereoscopic displays can augment the understanding of complex spatial structures and increase the detection of abnormalities. Stereoscopic viewing of medical data has proven to increase the detection rate in breast imaging. A stereoscopic presentation of noisy and transparent images in 3D ultrasound results in better visualization of the internal structures, however more empirical studies are needed to confirm the clinical relevance. For MRI and CT, where images are frequently rendered in 3D perspective, the added value of binocular depth has not yet been convincingly demonstrated. For MIS, stereoscopic displays can decrease surgery time and increase accuracy of surgical procedures. Performance of surgical procedures is similar when high resolution 2D displays are compared with lower resolution stereoscopic displays, indicating an image quality improvement for stereoscopic displays. Training and surgical planning already use computer simulations in 2D, however more research is needed to the benefit of stereoscopic displays in those applications. Overall there is a clear need for more empirical evidence that quantifies the added value of stereoscopic displays in medical domains, such that the medical community will have ample basis to invest in stereoscopic displays in all or some of the described medical applications.

  19. Balance and coordination after viewing stereoscopic 3D television

    PubMed Central

    Read, Jenny C. A.; Simonotto, Jennifer; Bohr, Iwo; Godfrey, Alan; Galna, Brook; Rochester, Lynn; Smulders, Tom V.

    2015-01-01

    Manufacturers and the media have raised the possibility that viewing stereoscopic 3D television (S3D TV) may cause temporary disruption to balance and visuomotor coordination. We looked for evidence of such effects in a laboratory-based study. Four hundred and thirty-three people aged 4–82 years old carried out tests of balance and coordination before and after viewing an 80 min movie in either conventional 2D or stereoscopic 3D, while wearing two triaxial accelerometers. Accelerometry produced little evidence of any change in body motion associated with S3D TV. We found no evidence that viewing the movie in S3D causes a detectable impairment in balance or in visuomotor coordination. PMID:26587261

  20. Web-based stereoscopic visualization for the global anatomy classroom.

    PubMed

    Kaspar, Mathias; Dech, Fred; Parsad, Nigel M; Silverstein, Jonathan C

    2011-01-01

    Many projects have focused on the improvement of virtual education. We have contributed with the global virtual anatomy course for teaching students in multiple locations with stereoscopic volume rendering, audio/video conferencing and additional materials. This year we focused on further simplifying the deployment of the classroom by using the new collaborative and web-based visualization system CoWebViz, to transfer stereoscopic visualization to the classrooms. Besides the necessary hardware installations for stereoscopy, only a web browser is necessary to view and to interact with the remote 3D stereo visualization. This system proved stable, gave higher quality images and increased ease of deployment. Its success within our classroom at the University of Chicago and Cardiff University has motivated us to continue CoWebViz development.

  1. Visual alchemy: stereoscopic adaptation produces kinetic depth from random noise.

    PubMed

    Nawrot, M; Blake, R

    1993-01-01

    Observers perceive incoherent motion and no hint of depth when viewing stochastic motion, in which stimulus elements move in all possible directions. As earlier work has shown, depth can be specified by introducing a brief interocular delay between the presentation of corresponding animation frames of this 'noise' to the left and right eyes. A study is reported in which observers were adapted to a stereoscopic display consisting of coherent planes of motion at different depths. This stereoscopic adaptation caused incoherent depthless motion to take on the qualities of structure and depth, and it could nullify the depth induced by interocular delay. The findings are interpreted within the context of a neural model consisting of units selectively responsive to different directions of motion at different planes of depth.

  2. Multimodal Stereoscopic Movie Summarization Conforming to Narrative Characteristics.

    PubMed

    Mademlis, Ioannis; Tefas, Anastasios; Nikolaidis, Nikos; Pitas, Ioannis

    2016-10-05

    Video summarization is a timely and rapidly developing research field with broad commercial interest, due to the increasing availability of massive video data. Relevant algorithms face the challenge of needing to achieve a careful balance between summary compactness, enjoyability and content coverage. The specific case of stereoscopic 3D theatrical films has become more important over the past years, but not received corresponding research attention. In the present work, a multi-stage, multimodal summarization process for such stereoscopic movies is proposed, that is able to extract a short, representative video skim conforming to narrative characteristics from a 3D film. At the initial stage, a novel, low-level video frame description method is introduced (Frame Moments Descriptor, or FMoD), that compactly captures informative image statistics from luminance, color, optical flow and stereoscopic disparity video data, both in a global and in a local scale. Thus, scene texture, illumination, motion and geometry properties may succinctly be contained within a single frame feature descriptor, which can subsequently be employed as a building block in any key-frame extraction scheme, e.g., for intra-shot frame clustering. The computed key-frames are then used to construct a movie summary in the form of a video skim, which is post-processed in a manner that also takes into account the audio modality. The next stage of the proposed summarization pipeline essentially performs shot pruning, controlled by a userprovided shot retention parameter, that removes segments from the skim based on the narrative prominence of movie characters in both the visual and the audio modalities. This novel process (Multimodal Shot Pruning, or MSP) is algebraically modelled as a multimodal matrix Column Subset Selection Problem, which is solved using an evolutionary computing approach. Subsequently, disorienting editing effects induced by summarization are dealt with, through manipulation of

  3. Psychometric Assessment of Stereoscopic Head-Mounted Displays

    DTIC Science & Technology

    2016-06-29

    per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and...60 call-to-landing task, including stereoscopic rendering using game-based simulation software, hardware/software antialiasing, and image warping ...virtual image distance (i.e., 0.25-diopter focal distance), and was capable of motion blur reduction (variable pixel hold time ). This HMD was selected

  4. Real-time, full resolution liquid crystal based stereoscopic display

    NASA Astrophysics Data System (ADS)

    Kirsch, James Clay

    Stereo imagery has been a goal in optics research since the invention of the stereoscope in 1834. While the market has been inundated with displays of various types, sizes, and formats, no general purpose, easy to use, inexpensive method for the display of imagery in stereo has been developed. The benefits of stereo vision are numerous and quickly become apparent when attempting to perform simple tasks without the aid of stereo cues. The proliferation of remotely operated vehicles has provided an even greater need for the capability to see the operational environment in stereo. Operators using conventional 'mono' vision displays lose critical depth cues causing operator fatigue and, frequently, fail to recognize potential hazards. Numerous approaches to the display of stereo imagery have been demonstrated; however, all suffer from various drawbacks, not the least of which is cost. Stereoscopic displays typically require the user to wear special headgear. Autostereoscopic displays, so named because they do not require the headgear, typically have tight limitations on the position of the viewer's head. The investigation into the application of two readily available, inexpensive liquid crystal panels sandwiched together to form a compact, rugged stereoscopic display is presented here. The appropriate drive signals are provided to the two stacked panels, which encode, in polarization, the left and right images. Standard polarized 3D glasses are then used to view the image in stereo. The theory behind the operation of the stereoscopic display, experimental determination of the liquid crystal display modulation characteristics, and the resulting modifications to the theory of operation are described.

  5. The technology of multiuser large display area and auto free-viewing stereoscopic display

    NASA Astrophysics Data System (ADS)

    Zhao, Tian-Qi; Zhang, He-Ling; Han, Jing

    2010-11-01

    No-glasses optical grating stereoscopic display is one of a chief development of stereoscopic display, but it is always confined by the range of stereoscopic visible and quantity of stereoscopic information and quantity of users. This research use the combination of Fresnel lens array and controllable point lights to output information of the two eyes of different users separately. Combining the technology of eyes-tracking, it can make no-glasses optical grating stereoscopic display be visible in 3D orientation range by multiuser in the condition of two-angle image sources. And it also can be visible in 360° stereoscopic overlook by one user in the condition of multi-angle image sources.

  6. A systematized WYSIWYG pipeline for digital stereoscopic 3D filmmaking

    NASA Astrophysics Data System (ADS)

    Mueller, Robert; Ward, Chris; Hušák, Michal

    2008-02-01

    Digital tools are transforming stereoscopic 3D content creation and delivery, creating an opportunity for the broad acceptance and success of stereoscopic 3D films. Beginning in late 2005, a series of mostly CGI features has successfully initiated the public to this new generation of highly-comfortable, artifact-free digital 3D. While the response has been decidedly favorable, a lack of high-quality live-action films could hinder long-term success. Liveaction stereoscopic films have historically been more time-consuming, costly, and creatively-limiting than 2D films - thus a need arises for a live-action 3D filmmaking process which minimizes such limitations. A unique 'systematized' what-you-see-is-what-you-get (WYSIWYG) pipeline is described which allows the efficient, intuitive and accurate capture and integration of 3D and 2D elements from multiple shoots and sources - both live-action and CGI. Throughout this pipeline, digital tools utilize a consistent algorithm to provide meaningful and accurate visual depth references with respect to the viewing audience in the target theater environment. This intuitive, visual approach introduces efficiency and creativity to the 3D filmmaking process by eliminating both the need for a 'mathematician mentality' of spreadsheets and calculators, as well as any trial and error guesswork, while enabling the most comfortable, 'pixel-perfect', artifact-free 3D product possible.

  7. Diagnosing perceptual distortion present in group stereoscopic viewing

    NASA Astrophysics Data System (ADS)

    Burton, Melissa; Pollock, Brice; Kelly, Jonathan W.; Gilbert, Stephen; Winer, Eliot; de la Cruz, Julio

    2012-03-01

    Stereoscopic displays are an increasingly prevalent tool for experiencing virtual environments, and the inclusion of stereo has the potential to improve distance perception within the virtual environment. When multiple users simultaneously view the same stereoscopic display, only one user experiences the projectively correct view of the virtual environment, and all other users view the same stereoscopic images while standing at locations displaced from the center of projection (CoP). This study was designed to evaluate the perceptual distortions caused by displacement from the CoP when viewing virtual objects in the context of a virtual scene containing stereo depth cues. Judgments of angles were distorted after leftward and rightward displacement from the CoP. Judgments of object depth were distorted after forward and backward displacement from the CoP. However, perceptual distortions of angle and depth were smaller than predicted by a ray-intersection model based on stereo viewing geometry. Furthermore, perceptual distortions were asymmetric, leading to different patterns of distortion depending on the direction of displacement. This asymmetry also conflicts with the predictions of the ray-intersection model. The presence of monocular depth cues might account for departures from model predictions.

  8. Optimal display conditions for quantitative analysis of stereoscopic cerebral angiograms

    SciTech Connect

    Charland, P.; Peters, T. |

    1996-10-01

    For several years the authors have been using a stereoscopic display as a tool in the planning of stereotactic neurosurgical techniques. This PC-based workstation allows the surgeon to interact with and view vascular images in three dimensions, as well as to perform quantitative analysis of the three-dimensional (3-D) space. Some of the perceptual issues relevant to the presentation of medical images on this stereoscopic display were addressed in five experiments. The authors show that a number of parameters--namely the shape, color, and depth cue, associated with a cursor--as well as the image filtering and observer position, have a role in improving the observer`s perception of a 3-D image and his ability to localize points within the stereoscopically presented 3-D image. However, an analysis of the results indicates that while varying these parameters can lead to an effect on the performance of individual observers, the effects are not consistent across observers, and the mean accuracy remains relatively constant under the different experimental conditions.

  9. Stereoscopic Displays And The Human Dual Visual System

    NASA Astrophysics Data System (ADS)

    Clapp, Robert E.

    1986-05-01

    There is only one real world. We "see" that world as extending into three dimensions because we look at it with two visual systems and with two eyes. We are not presented with two "pictures" of the real world, but with two separate sets of inputs into two separate systems. The analog of the eye as a camera has been a constant problem in the visualization of the "seeing" process. Overcoming the persistence of such an approach is the first requirement in developing a true stereoscopic display system. The eye is a dynamic sensing apparatus and supplies the brain with visual inputs. The brain constructs the scene we "see", and is responsible for our perceptions of the visual world. The sensory inputs from the human dual visual system (Ambient - wide FOV, Focal - detail FOV) are combined with other body senses in this perceptual process. Indeed, other body senses, in some degree, direct and control where and at what our eyes look. This process of conceptualization of the "real" world as perceived by ourselves can be related only within limits to the "real" world as perceived by others.. This paper addresses the processes by which our minds (with sensor inputs) work to form our stereoscopic perceptual concepts of the world, real or simulated, and the advantages (and problems) caused by our egocentric reduction of those data inputs. Discussion and evaluation of stereoscopic display systems compares current and future display systems.

  10. Computational model of stereoscopic 3D visual saliency.

    PubMed

    Wang, Junle; Da Silva, Matthieu Perreira; Le Callet, Patrick; Ricordel, Vincent

    2013-06-01

    Many computational models of visual attention performing well in predicting salient areas of 2D images have been proposed in the literature. The emerging applications of stereoscopic 3D display bring an additional depth of information affecting the human viewing behavior, and require extensions of the efforts made in 2D visual modeling. In this paper, we propose a new computational model of visual attention for stereoscopic 3D still images. Apart from detecting salient areas based on 2D visual features, the proposed model takes depth as an additional visual dimension. The measure of depth saliency is derived from the eye movement data obtained from an eye-tracking experiment using synthetic stimuli. Two different ways of integrating depth information in the modeling of 3D visual attention are then proposed and examined. For the performance evaluation of 3D visual attention models, we have created an eye-tracking database, which contains stereoscopic images of natural content and is publicly available, along with this paper. The proposed model gives a good performance, compared to that of state-of-the-art 2D models on 2D images. The results also suggest that a better performance is obtained when depth information is taken into account through the creation of a depth saliency map, rather than when it is integrated by a weighting method.

  11. A composition tool for creating comfortable stereoscopic images

    NASA Astrophysics Data System (ADS)

    Quintus, Katharina; Halle, Michael

    2008-02-01

    Although stereoscopic imaging has potential value in many computer graphics applications, the design principles for creating effective three-dimensional images are not widely known in the graphics community. Poorly designed images may fail to convey convincing 3D information about the visualized scene or object. At their worst, stereo images designed without attention to physiological limits can produce the kinds of eye strain, headaches, and generally unpleasant viewing experiences that are unfortunately now associated with 3D by many people. This paper presents a graphical software application that assists the user in composing stereoscopic computer graphic images that minimize conflicting depth cues and unwanted physiological effects. This prototype application is designed to help novice users adjust parameters of the virtual stereo camera and compose stereoscopic views of three-dimensional models. Specifically, the tool detects window violations and excessive disparity, graphically displays affected regions of the object or scene, and suggests ways to minimize discomfort. The user interface refrains from using technical terms, guiding the inexperienced user to adjust underlying image parameters like camera position, camera view angle, location of image plane, viewing distance, and stereo base to match the scene, the viewing environment, and the user's preferences.

  12. Visually preserving stereoscopic image retargeting using depth carving

    NASA Astrophysics Data System (ADS)

    Lu, Dawei; Ma, Huadong; Liu, Liang

    2016-03-01

    This paper presents a method for retargeting a pair of stereoscopic images. Previous works have leveraged seam carving and image warping methods for two-dimensional image editing to address this issue. However, they did not consider the full advantages of the properties of stereoscopic images. Our approach offers substantial performance improvements over the state-of-the-art; the key insights driving the approach are that the input image pair can be decomposed into different depth layers according to the disparity and image segmentation, and the depth cues allow us to address the problem in a three-dimensional (3-D) space domain for best preserving objects. We propose depth carving that extends seam carving in a single image to resize the stereo image pair with disparity consistency. Our method minimizes the shape distortion and preserves object boundaries by creating new occlusions. As a result, the retargeted image pair preserves the stereoscopic quality and protects the original 3-D scene structure. Experimental results demonstrate that our method outperforms the previous methods.

  13. Single-channel stereoscopic ophthalmology microscope based on TRD

    NASA Astrophysics Data System (ADS)

    Radfar, Edalat; Park, Jihoon; Lee, Sangyeob; Ha, Myungjin; Yu, Sungkon; Jang, Seulki; Jung, Byungjo

    2016-03-01

    A stereoscopic imaging modality was developed for the application of ophthalmology surgical microscopes. A previous study has already introduced a single-channel stereoscopic video imaging modality based on a transparent rotating deflector (SSVIM-TRD), in which two different view angles, image disparity, are generated by imaging through a transparent rotating deflector (TRD) mounted on a stepping motor and is placed in a lens system. In this case, the image disparity is a function of the refractive index and the rotation angle of TRD. Real-time single-channel stereoscopic ophthalmology microscope (SSOM) based on the TRD is improved by real-time controlling and programming, imaging speed, and illumination method. Image quality assessments were performed to investigate images quality and stability during the TRD operation. Results presented little significant difference in image quality in terms of stability of structural similarity (SSIM). A subjective analysis was performed with 15 blinded observers to evaluate the depth perception improvement and presented significant improvement in the depth perception capability. Along with all evaluation results, preliminary results of rabbit eye imaging presented that the SSOM could be utilized as an ophthalmic operating microscopes to overcome some of the limitations of conventional ones.

  14. Effect of geometric field of view on stereoscopic spatial judgments.

    PubMed

    Banton, P; Thompson, P; Quinlan, P T

    2001-01-01

    Within a stereoscopic display the field of view (FOV) was held constant at 13.86 degrees while the geometric field of view (GFOV) was varied across four levels: 0 degrees (parallel), 13.86 degrees (veridical), 50 degrees and 100 degrees. Participants performed a distance-matching task where they adjusted the distance of a standard track from the centre of the display to match the distance of a target track from the same point. The results indicated that while the least error occurred in the veridical GFOV condition, small variations of GFOV away from the veridical have little effect. Large differences between FOV and GFOV (36 degrees and 86 degrees) increased errors markedly. A trend toward better performance in the veridical GFOV condition relative to the parallel GFOV condition suggests that the use of linear perspective information in a stereoscopic display may facilitate more accurate spatial perception. Actual or potential applications of this work include stereoscopic display design in aviation and non-aviation settings.

  15. Stereoscopic see-through retinal projection head-mounted display

    NASA Astrophysics Data System (ADS)

    Takahashi, Hideya; Hirooka, Shun

    2008-02-01

    See-through head-mounted displays (HMDs) provide an effective capability for Mixed Reality. Some conventional monocular see-through HMDs have been developed and they can display two-dimensional virtual information. However, when two-dimensional virtual information is displayed, observers can understand it although it has no relation to real-world objects. What an observer sees needs to be augmented by virtual information in accordance with the real object. Such environments are provided by a stereoscopic see-through HMD. Though, this method has generally the drawback of dissociation between accommodation and convergence. In order to overcome this problem, we propose a new stereoscopic see-through HMD by using the principle of the modified Maxwellian View which solves the problem of the narrow viewing area. This HMD has an extremely long focal depth, and provides natural concordant accommodation and convergence. The proposed HMD consists of two pairs of an HOE and an LCD. An HOE is used as a combiner and a condenser lens which performs the Maxwellian View, and virtual 3D images can be displayed at any distance from viewer. We have verified that the accommodation consistent with the convergence by using proposed HMD. This paper describes the principle of the proposed stereoscopic see-through retinal projection HMD and also describes the experimental results.

  16. Perception of absolute and relative distances in stereoscopic image

    NASA Astrophysics Data System (ADS)

    Shidoji, Kazunori; Funakoshi, Masakazu; Ogawa, Masahiko

    2010-02-01

    In 3-D movies and virtual reality and augmented reality systems, stereoscopic images are used to improve perceptions of realism and depth. The distance (depth) that we perceive can be classified into absolute distance, which is the distance between the observer and the objects, and relative distance, which is the distance between the objects. It is known that in the real environment these two distances are independent. Previous studies have reported that we underestimate or overestimate the absolute distance in stereoscopic images under some circumstances. We examined perceptions of both absolute and relative distances in stereoscopic images to investigate the depth perception of virtual objects. The results of the experiments showed that (1) the perceived absolute distance from the observer to images in front of the screen was nearly accurate and that to images farther behind the screen was underestimated; (2) this underestimation tendency increased in short viewing distances; and (3) the relative distance from the screen to images in front of the screen was overestimated, whereas that to images farther behind the screen was underestimated.

  17. In-flight evaluation of stereoscopic imagery in helicopter cockpits

    NASA Astrophysics Data System (ADS)

    Jennings, Sion A.; Baillie, Stewart W.

    1997-07-01

    The National Research Council's (NRC) Cockpit Technologies Program flight tested a stereoscopic 3D display format to determine the feasibility of using pictorial and stereoscopic cues during helicopter instrument approach procedures (IAP). Three qualified test pilots flew a series of approach procedures using a modified conventional electronic flight instrumentation format, a pictorial display formate, and a pictorial stereoscopic display format. The preliminary evaluation focused on the effect of display format on pilot performance during the approach task, from an approach intercept to the decision height. Performance criteria such as aircraft speed error, localizer error, and glide slope error were measured. Additionally, pilots answered a questionnaire on each display format, and rated the workload required to fly the approaches using the Cooper-Harper scale. Pilots were able to complete approaches to safe landings using any of the display formats. Pilots reported that the pictorial format improved their situation awareness during the approach. Pilots also reported that the stereo cues incorporated in the display design did not significantly enhance their ability to perform IAP. The pictorial display contained several strong monocular depth cues such as occlusion, linear perspective, and motion flow; therefore the stereo cues were of limited value. Pilots most preferred the conventional display, which provided the most accurate tracking capabilities and lowest workload. Pilots encountered a few acceptance problems with the stereo display, most notably, losing the stereo effect when viewing the prototype stereo display off the central viewing axis.

  18. Architecture for high performance stereoscopic game rendering on Android

    NASA Astrophysics Data System (ADS)

    Flack, Julien; Sanderson, Hugh; Shetty, Sampath

    2014-03-01

    Stereoscopic gaming is a popular source of content for consumer 3D display systems. There has been a significant shift in the gaming industry towards casual games for mobile devices running on the Android™ Operating System and driven by ARM™ and other low power processors. Such systems are now being integrated directly into the next generation of 3D TVs potentially removing the requirement for an external games console. Although native stereo support has been integrated into some high profile titles on established platforms like Windows PC and PS3 there is a lack of GPU independent 3D support for the emerging Android platform. We describe a framework for enabling stereoscopic 3D gaming on Android for applications on mobile devices, set top boxes and TVs. A core component of the architecture is a 3D game driver, which is integrated into the Android OpenGL™ ES graphics stack to convert existing 2D graphics applications into stereoscopic 3D in real-time. The architecture includes a method of analyzing 2D games and using rule based Artificial Intelligence (AI) to position separate objects in 3D space. We describe an innovative stereo 3D rendering technique to separate the views in the depth domain and render directly into the display buffer. The advantages of the stereo renderer are demonstrated by characterizing the performance in comparison to more traditional render techniques, including depth based image rendering, both in terms of frame rates and impact on battery consumption.

  19. Measurement of perceived stereoscopic sensation through disparity metrics and compositions

    NASA Astrophysics Data System (ADS)

    Toyosawa, Satoshi; Kawai, Takashi

    2014-03-01

    Literatures use disparity as a principle measure evaluating discomfort, various artifacts, or movie production styles associated to stereoscopy, yet, statistics used to represent image or frame are often different. The current study examines 20 disparity statistics to find metrics that would best represent subjective stereoscopic sensation. Additionally, effect of disparity distribution pattern within an image is considered: Here, the patterns are categorised either single-peak or multiple-peak from the shape of disparity histogram. In the experiment, 14 stereoscopic images were presented to 15 subjects. Each subject evaluated perceived sense of distance and volume (3D space) through 7 points Likert scale. The result shows that the statistics that correlated significantly to the subjective sensation differed by the disparity compositions, hence, the metrics should be chosen accordingly. For the sense of distance, maximum, range, and the difference between 95th and 5th percentiles were found to be appropriate metrics under the single-peak, and minimum, contrast, and 5th percentile were representative under the multiple-peak. Similarly, for the sense of volume, range was found to be appropriate under the single-peak, but no metrics was found under the multiple-peak. The discrepancy is assumed due to different observation styles under differently composed images. We believe that the current study provides optimal disparity metrics for stereoscopic sensation measurements.

  20. Coffea arabica instant coffee--chemical view and immunomodulating properties.

    PubMed

    Capek, Peter; Paulovičová, Ema; Matulová, Mária; Mislovičová, Danica; Navarini, Luciano; Suggi-Liverani, Furio

    2014-03-15

    Results of chemical analyses and immunological studies of two Coffea arabica instant coffee powders obtained by freeze-dried (ICPf) and spray-dried (ICPs) procedures, and arabinogalactan-protein (AGP3) obtained from ICPf are presented. For instant coffee powders no significant differences have been found in carbohydrate (ICPf: 37%, ICPs: 38%) as well as in caffeine (ICPf: 3.0%, ICPs: 3.4%) contents. Their (1)H NMR spectra revealed differences in trigonelline and chlorogenic acids content and in a degree of AGP backbone substitution. Immunobiological tests of all samples (ICPf, ICPs, AGP2 and AGP3) revealed a significant immunostimulatory effect on induction of interleukin 2 and free radicals secretion by mice immunocytes. Moreover, tests revealed more pronounced effect of arabinogalactans AGP2 and AGP3 compared to instant coffee powders (ICPf and ICPs).

  1. Effectiveness of Stereoscopic Displays for Indirect-Vision Driving and Robot Teleoperation

    DTIC Science & Technology

    2010-08-01

    Effectiveness of Stereoscopic Displays for Indirect-Vision Driving and Robot Teleoperation by Jessie Y. C. Chen, Razia V. N. Oden, Caitlin...Ground, MD 21005-5425 ARL-TR-5259 August 2010 Effectiveness of Stereoscopic Displays for Indirect-Vision Driving and Robot Teleoperation...Stereoscopic Displays for Indirect-Vision Driving and Robot Teleoperation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  2. Instant hot noodles: do they need to burn?

    PubMed

    Wu, C; Tan, A L; Maze, D A E; Holland, A J A

    2013-03-01

    Scalds and contact burns in children may occur as the result of spillage of hot food and drinks, including instant hot noodles. This study sought to determine the frequency of noodle burns in children and investigate the thermal properties of instant hot noodles. Data on instant hot noodle burns in children were retrieved from the New South Wales Severe Burn Injury Database between 2005 and 2010. Five widely available brands of instant hot noodles, including three cup and two packet varieties, were prepared following the manufacturer's instructions. For each preparation the initial temperature after cooking was recorded, together with the time to cool to 50°C. 291 children sustained instant hot noodle burns over the 6 year study period, representing 5.4% of all children referred to our burns unit. Over a third received inadequate first aid. Cup noodles cooked with boiling water reached the highest temperature of over 80°C and took the longest time to cool to 50°C: on average 52.3 min. Cup noodles in smaller, narrower containers achieved higher post-cooking temperatures compared to noodles in wider, bowel shaped containers. Packet noodles cooked in a Microwave oven attained lower peak temperatures and shorter cooling times compared to cup noodles. Although relatively uncommon in children, instant hot noodle burns often received inadequate first aid. When cooked according to manufacturer's instructions, noodles generally exceeded temperatures sufficient to cause a burn. Consumers and parents need to be aware of the risks of burn when preparing these foods. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  3. A microscopic modeling of the instant coffee effect

    NASA Astrophysics Data System (ADS)

    Isoda, M.; Nishimori, Y.

    2014-03-01

    So-called the instant coffee effect is well known in the field of the physics education. The effect is explained that the sound yielded by touching the cup with a spoon is shifted to low-pitched by adulterating bubble owing to putting a spoon of instant coffee into hot water. The phenomenon has been interpreted with the averaged density and compressibility of the fluid in the macroscopic relation for the sound velocity, . We introduce the linear coupled oscillator model with finite oscillators including the impurity air-mass oscillator. The model may well reproduce the increase in the shift of the eigen frequency accompanying with the amount of bubble.

  4. Computation of instant system availability and its applications.

    PubMed

    Hagenimana, Emmanuel; Lixin, Song; Kandege, Patrick

    2016-01-01

    The instant system availability [Formula: see text] of a repairable system with the renewal equation was studied. The starting point monotonicity of [Formula: see text] was proved and the upper bound of [Formula: see text] is also derived. It was found that the interval of instant system availability monotonically decreases. In addition, we provide examples that validate the analytically derived properties of [Formula: see text] based on the Lognormal, Gamma and Weibull distributions and the results show that the value of T is slightly smaller than its value defined in Theorem 2. The procedure of using a bathtub as application for this article is also discussed.

  5. Efficient stereoscopic contents file format on the basis of ISO base media file format

    NASA Astrophysics Data System (ADS)

    Kim, Kyuheon; Lee, Jangwon; Suh, Doug Young; Park, Gwang Hoon

    2009-02-01

    A lot of 3D contents haven been widely used for multimedia services, however, real 3D video contents have been adopted for a limited applications such as a specially designed 3D cinema. This is because of the difficulty of capturing real 3D video contents and the limitation of display devices available in a market. However, diverse types of display devices for stereoscopic video contents for real 3D video contents have been recently released in a market. Especially, a mobile phone with a stereoscopic camera has been released in a market, which provides a user as a consumer to have more realistic experiences without glasses, and also, as a content creator to take stereoscopic images or record the stereoscopic video contents. However, a user can only store and display these acquired stereoscopic contents with his/her own devices due to the non-existence of a common file format for these contents. This limitation causes a user not share his/her contents with any other users, which makes it difficult the relevant market to stereoscopic contents is getting expanded. Therefore, this paper proposes the common file format on the basis of ISO base media file format for stereoscopic contents, which enables users to store and exchange pure stereoscopic contents. This technology is also currently under development for an international standard of MPEG as being called as a stereoscopic video application format.

  6. InstantScope: a low-cost whole slide imaging system with instant focal plane detection.

    PubMed

    Guo, Kaikai; Liao, Jun; Bian, Zichao; Heng, Xin; Zheng, Guoan

    2015-09-01

    We report the development of a high-throughput whole slide imaging (WSI) system by adapting a cost-effective optomechanical add-on kit to existing microscopes. Inspired by the phase detection concept in professional photography, we attached two pinhole-modulated cameras at the eyepiece ports for instant focal plane detection. By adjusting the positions of the pinholes, we can effectively change the view angle for the sample, and as such, we can use the translation shift of the two pinhole-modulated images to identify the optimal focal position. By using a small pinhole size, the focal-plane-detection range is on the order of millimeter, orders of magnitude longer than the objective's depth of field. We also show that, by analyzing the phase correlation of the pinhole-modulated images, we can determine whether the sample contains one thin section, folded sections, or multiple layers separated by certain distances - an important piece of information prior to a detailed z scan. In order to achieve system automation, we deployed a low-cost programmable robotic arm to perform sample loading and $14 stepper motors to drive the microscope stage to perform x-y scanning. Using a 20X objective lens, we can acquire a 2 gigapixel image with 14 mm by 8 mm field of view in 90 seconds. The reported platform may find applications in biomedical research, telemedicine, and digital pathology. It may also provide new insights for the development of high-content screening instruments.

  7. Instant Messenger in Enrollment Management: Evaluating Use and Effectiveness

    ERIC Educational Resources Information Center

    Zalanowski, Kevin

    2007-01-01

    This study represented a formal quantitative evaluation of the potential for instant messenger (IM) technology as an outreach tool for undergraduate college admission. Conclusions focused on the popularity of IM, and student use in a formal counselor/student relationship. (Contains 4 tables and 2 figures.)

  8. Instant Messaging Reference: Users' Evaluation of Library Chat.

    ERIC Educational Resources Information Center

    Ruppel, Margie; Fagan, Jody Condit

    2002-01-01

    Analyzes survey results of university students who used the instant messaging (IM) reference service at Southern Illinois University Carbondale's library. Focuses on the results of two surveys, including a comparison of IM reference and traditional reference desk experiences; provides an overview of the IM reference system and usage data; and…

  9. Can Turnitin Be Used to Provide Instant Formative Feedback?

    ERIC Educational Resources Information Center

    Rolfe, Vivien

    2011-01-01

    New students face the challenge of making a smooth transition between school and university, and with regards to academic practice, there are often gaps between student expectations and university requirements. This study supports the use of the plagiarism detection service Turnitin to give students instant feedback on essays to help improve…

  10. Instant Messaging Reference in an Academic Library: A Case Study.

    ERIC Educational Resources Information Center

    Foley, Marianne

    2002-01-01

    During the 2000-2001 academic year, the General Libraries of the University at Buffalo conducted a pilot project to assess feasibility of providing reference through instant messaging. Describes the project, its implementation, the software used, staffing issues, and publicity efforts. Discusses results of the project in terms of user…

  11. The Effect of Instant Messaging on Lecture Retention

    ERIC Educational Resources Information Center

    McVaugh, Nathan Kant

    2012-01-01

    The impact of instant message interruptions via computer on immediate lecture retention for college students was examined. While watching a 24-minute video of a classroom lecture, students received various numbers of related-to-lecture ("Is consistent use of the eye contact method necessary for success?") versus not-related-to lecture…

  12. The Effect of Instant Messaging on Lecture Retention

    ERIC Educational Resources Information Center

    McVaugh, Nathan Kant

    2012-01-01

    The impact of instant message interruptions via computer on immediate lecture retention for college students was examined. While watching a 24-minute video of a classroom lecture, students received various numbers of related-to-lecture ("Is consistent use of the eye contact method necessary for success?") versus not-related-to lecture…

  13. Instant Messaging Reference in an Academic Library: A Case Study.

    ERIC Educational Resources Information Center

    Foley, Marianne

    2002-01-01

    During the 2000-2001 academic year, the General Libraries of the University at Buffalo conducted a pilot project to assess feasibility of providing reference through instant messaging. Describes the project, its implementation, the software used, staffing issues, and publicity efforts. Discusses results of the project in terms of user…

  14. From a Distance: Robust Reference Service via Instant Messaging

    ERIC Educational Resources Information Center

    Meulemans, Yvonne Nalani; Carr, Allison; Ly, Pearl

    2010-01-01

    Reference service via instant messaging (IM) has significant potential to benefit distance learners. There has been wide experimentation with IM to expand reference services in libraries across the US, with mixed results. Concern has been expressed that IM cannot provide the same reference experience as face-to-face interactions. One academic…

  15. AskNow Instant Messaging: Innovation in Virtual Reference

    ERIC Educational Resources Information Center

    Davis, Kate

    2007-01-01

    In late 2006, the National Library of Australia (NLA) implemented a trial Instant Messaging (IM) service that ran in parallel with the AskNow chat reference service for a six month period. The trial was a resounding success, proving both a demand for an IM service and the suitability of the medium for reference service provision in a collaborative…

  16. Teaching "Instant Experience" with Graphical Model Validation Techniques

    ERIC Educational Resources Information Center

    Ekstrøm, Claus Thorn

    2014-01-01

    Graphical model validation techniques for linear normal models are often used to check the assumptions underlying a statistical model. We describe an approach to provide "instant experience" in looking at a graphical model validation plot, so it becomes easier to validate if any of the underlying assumptions are violated.

  17. Assessing the Use of Instant Messaging in Online Learning Environments

    ERIC Educational Resources Information Center

    Contreras-Castillo, Juan; Perez-Fragoso, Carmen; Favela, Jesus

    2006-01-01

    There is a body of evidence supporting the claim that informal interactions in educational environments have positive effects on learning. In order to increase the opportunities of informal interaction in online courses, an instant messaging tool, called CENTERS, was developed and integrated into online learning environments. This tool provides…

  18. Characterization of mutagenic activity in instant hot beverage powders.

    PubMed

    Johansson, M A; Knize, M G; Jägerstad, M; Felton, J S

    1995-01-01

    Extracts of several grain-based coffee-substitute blends and instant coffees were mutagenic in the Ames/Salmonella test using TA98, YG1024, and YG1029 with metabolic activation. The beverage powders induced 150 to 500 TA98 and 1,150 to 4,050 YG1024 revertant colonies/g, respectively. Increased sensitivity was achieved using strain YG1024. No mutagenic activity was found in instant hot cocoa products. The mutagenic activity in the beverage powders was shown to be stable to heat and the products varied in resistance to acid nitrite treatment. Differential bacterial strain specificity, and a requirement for metabolic activation suggest that aromatic amines are present. Characterization of the mutagenic activity, using HPLC and the Ames test of the collected fractions, showed the coffee-substitute blends and instant coffees contain several mutagenic compounds. Known heterocyclic amines are not responsible for the major part of the mutagenic activity. The main mutagenic activity in grain-based coffee-substitute blends and instant coffees is due to several unidentified compounds, which are most likely aromatic amines.

  19. Measuring the Impact of High Quality Instant Feedback on Learning

    ERIC Educational Resources Information Center

    Nutbrown, Stephen; Higgins, Colin; Beesley, Su

    2016-01-01

    This paper examines the impact of a novel assessment technique that has been used to improve the feedback given to second year Computer Science students at the University of Nottingham. Criteria for effective, high quality feedback are discussed. An automated marking system (The Marker's Apprentice--TMA) produces instant feedback in synergy with…

  20. Instant Messaging Language in Jordanian Female School Students' Writing

    ERIC Educational Resources Information Center

    Rabab'ah, Ghaleb A.; Rabab'ah, Bayan B.; Suleiman, Nour A.

    2016-01-01

    This study seeks to examine the existence of Instant Messaging language phenomenon among female teenagers in some Jordanian private schools and its influence on their learning experience, mainly literacy. It also raises questions about the characteristics of textese as well as teachers' attitude towards their students' use of SMS language in their…

  1. Can Turnitin Be Used to Provide Instant Formative Feedback?

    ERIC Educational Resources Information Center

    Rolfe, Vivien

    2011-01-01

    New students face the challenge of making a smooth transition between school and university, and with regards to academic practice, there are often gaps between student expectations and university requirements. This study supports the use of the plagiarism detection service Turnitin to give students instant feedback on essays to help improve…

  2. Lexical Cues of Interaction Involvement in Dyadic Instant Messaging Conversations

    ERIC Educational Resources Information Center

    Nguyen, Duyen T.; Fussell, Susan R.

    2014-01-01

    We explore how people express and interpret lexical cues of interaction involvement in dyadic conversations via instant messaging (IM) in two studies. In Study 1, an experiment with 60 participants, we manipulated level of involvement in a conversation with a distraction task. We examined how participants' uses of verbal cues such as pronouns…

  3. Lexical Cues of Interaction Involvement in Dyadic Instant Messaging Conversations

    ERIC Educational Resources Information Center

    Nguyen, Duyen T.; Fussell, Susan R.

    2014-01-01

    We explore how people express and interpret lexical cues of interaction involvement in dyadic conversations via instant messaging (IM) in two studies. In Study 1, an experiment with 60 participants, we manipulated level of involvement in a conversation with a distraction task. We examined how participants' uses of verbal cues such as pronouns…

  4. AskNow Instant Messaging: Innovation in Virtual Reference

    ERIC Educational Resources Information Center

    Davis, Kate

    2007-01-01

    In late 2006, the National Library of Australia (NLA) implemented a trial Instant Messaging (IM) service that ran in parallel with the AskNow chat reference service for a six month period. The trial was a resounding success, proving both a demand for an IM service and the suitability of the medium for reference service provision in a collaborative…

  5. Repeated Instant Self-healing Shape Memory Composites

    NASA Astrophysics Data System (ADS)

    Wang, C. C.; Ding, Z.; Purnawali, H.; Huang, W. M.; Fan, H.; Sun, L.

    2012-12-01

    We present a shape memory composite which is made of two types of shape memory materials, namely shape memory alloy (SMA) and shape memory hybrid. This composite has repeated instant self-healing function by means of not only shape recovery but also strength recovery (over 80%). The activation of the self-healing function is triggered by joule heating the embedded SMA.

  6. Young People's Everyday Literacies: The Language Features of Instant Messaging

    ERIC Educational Resources Information Center

    Haas, Christina; Takayoshi, Pamela

    2011-01-01

    In this article, we examine writing in the context of new communication technologies as a kind of everyday literacy. Using an inductive approach developed from grounded theory, we analyzed a 32,000-word corpus of college students' Instant Messaging (IM) exchanges. Through our analysis of this corpus, we identify a fifteen-item taxonomy of IM…

  7. Teaching "Instant Experience" with Graphical Model Validation Techniques

    ERIC Educational Resources Information Center

    Ekstrøm, Claus Thorn

    2014-01-01

    Graphical model validation techniques for linear normal models are often used to check the assumptions underlying a statistical model. We describe an approach to provide "instant experience" in looking at a graphical model validation plot, so it becomes easier to validate if any of the underlying assumptions are violated.

  8. Instant Messaging Reference: Users' Evaluation of Library Chat.

    ERIC Educational Resources Information Center

    Ruppel, Margie; Fagan, Jody Condit

    2002-01-01

    Analyzes survey results of university students who used the instant messaging (IM) reference service at Southern Illinois University Carbondale's library. Focuses on the results of two surveys, including a comparison of IM reference and traditional reference desk experiences; provides an overview of the IM reference system and usage data; and…

  9. [Effects of stereoscopic cultivation on photosynthetic characteristics and growth of Tulipa edulis].

    PubMed

    Sun, Yuan; Guo, Qiao-Sheng; Zhu, Zai-Biao; Lin, Jian-Luo; Zhou, Bo-Ya; Zhao, Min-Jie

    2016-06-01

    The effect of stereoscopic cultivation on the growth, photosynthetic characteristics and yield of Tulipa edulis was studied to explore the feasibility of stereoscopic cultivation on efficient cultivation of T.edulis. Total leaf area and photosynthetic parameters of T.edulis under stereoscopic cultivation (the upper, middle and the lower layers ) and the control were measured using LI-3100 leaf area meter and LI-6400XT photosynthesis system in the growing peak period of T.edulis.Plant biomass and biomass allocation were also determined.In addition, the bulb regeneration and yield of T.edulis were measured in the harvesting time.The results indicated that in the middle layer of stereoscopic cultivation, leaf biomass proportion was the highest, but total bulb fresh and dry weight and output growth (fresh weight) were the lowest among the treatments.And total bulb fresh weight in the middle of stereoscopic cultivation reduced significantly, by 22.84%, compared with the control.Light intensity in the lower layer of stereoscopic cultivation was moderate, in which T.edulis net photosynthetic rate and water use efficiency were higher than those of the other layers of stereoscopic cultivation, and bulb biomass proportion was the highest in all the treatments.No significant difference was detected in the total bulb fresh weight, dry weight and output growth (fresh weight) between the middle layer of stereoscopic cultivation and the control.In general, there was no significant difference in the growth status of T.edulis between stereoscopic cultivation and the control.Stereoscopic cultivation increased the yield of T.edulis by 161.66% in fresh weight and 141.35% in dry weight compared with the control in the condition of the same land area, respectively.In conclusion, stereoscopic cultivation can improve space utilization, increase the production, and achieve the high density cultivation of T.edulis. Copyright© by the Chinese Pharmaceutical Association.

  10. Instant food products as a source of silicon.

    PubMed

    Prescha, Anna; Zabłocka-Słowińska, Katarzyna; Hojka, Anna; Grajeta, Halina

    2012-12-01

    Silicon is a trace element for humans, and is absorbed from food in the form of orthosilicic acid. Instant food products are part of a constantly growing market of convenience foods, which have not been evaluated yet as sources of silicon. In this study the total and soluble silicon contents in different instant food products were determined by using graphite furnace atomic absorption spectrometry (GF-AAS). A selection of instant products commercially available in Wroclaw were analyzed: soups, main courses, coffee drinks, jellies and puddings. Total silicon contents in soups, main courses and coffee drinks ranged widely and reached the values: 0.10-30.20, 0.63-37.91 and 0.21-13.37mg/serving, respectively. These products contained 0.05-1.26mg of soluble silicon per serving. The total silicon content in jellies and puddings did not exceed 0.36mg and 2.42mg/serving, respectively. Among the analyzed desserts the highest level of soluble silicon was found in chocolate puddings: 0.36-0.41mg/serving. The silicon level in servings of the studied instant products when prepared with the appropriate amount of water was also estimated. The mean content of silicon determined in samples of drinking water from Wrocław and the vicinity, which was used for the estimation, amounted to 7.09mg/l. The total silicon content in ready-to-eat products ranged from 1.32 to 39.21mg/serving. In conclusion, some of the analyzed instant foods contained very high amounts of silicon, however the content of the soluble, and hence available, form of this element was low. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Stereoscopic virtual reality models for planning tumor resection in the sellar region.

    PubMed

    Wang, Shou-sen; Zhang, Shang-ming; Jing, Jun-jie

    2012-11-28

    It is difficult for neurosurgeons to perceive the complex three-dimensional anatomical relationships in the sellar region. To investigate the value of using a virtual reality system for planning resection of sellar region tumors. The study included 60 patients with sellar tumors. All patients underwent computed tomography angiography, MRI-T1W1, and contrast enhanced MRI-T1W1 image sequence scanning. The CT and MRI scanning data were collected and then imported into a Dextroscope imaging workstation, a virtual reality system that allows structures to be viewed stereoscopically. During preoperative assessment, typical images for each patient were chosen and printed out for use by the surgeons as references during surgery. All sellar tumor models clearly displayed bone, the internal carotid artery, circle of Willis and its branches, the optic nerve and chiasm, ventricular system, tumor, brain, soft tissue and adjacent structures. Depending on the location of the tumors, we simulated the transmononasal sphenoid sinus approach, transpterional approach, and other approaches. Eleven surgeons who used virtual reality models completed a survey questionnaire. Nine of the participants said that the virtual reality images were superior to other images but that other images needed to be used in combination with the virtual reality images. The three-dimensional virtual reality models were helpful for individualized planning of surgery in the sellar region. Virtual reality appears to be promising as a valuable tool for sellar region surgery in the future.

  12. Automatic fusion of freehand endoscopic brain images to three-dimensional surfaces: creating stereoscopic panoramas.

    PubMed

    Dey, Damini; Gobbi, David G; Slomka, Piotr J; Surry, Kathleen J M; Peters, Terence M

    2002-01-01

    A major limitation of the use of endoscopes in minimally invasive surgery is the lack of relative context between the endoscope and its surroundings. The purpose of this work was to fuse images obtained from a tracked endoscope to surfaces derived from three-dimensional (3-D) preoperative magnetic resonance or computed tomography (CT) data, for assistance in surgical planning, training and guidance. We extracted polygonal surfaces from preoperative CT images of a standard brain phantom and digitized endoscopic video images from a tracked neuro-endoscope. The optical properties of the endoscope were characterized using a simple calibration procedure. Registration of the phantom (physical space) and CT images (preoperative image space) was accomplished using fiducial markers that could be identified both on the phantom and within the images. The endoscopic images were corrected for radial lens distortion and then mapped onto the extracted surfaces via a two-dimensional 2-D to 3-D mapping algorithm. The optical tracker has an accuracy of about 0.3 mm at its centroid, which allows the endoscope tip to be localized to within 1.0 mm. The mapping operation allows multiple endoscopic images to be "painted" onto the 3-D brain surfaces, as they are acquired, in the correct anatomical position. This allows panoramic and stereoscopic visualization, as well as navigation of the 3-D surface, painted with multiple endoscopic views, from arbitrary perspectives.

  13. Stereoscopic virtual reality models for planning tumor resection in the sellar region

    PubMed Central

    2012-01-01

    Background It is difficult for neurosurgeons to perceive the complex three-dimensional anatomical relationships in the sellar region. Methods To investigate the value of using a virtual reality system for planning resection of sellar region tumors. The study included 60 patients with sellar tumors. All patients underwent computed tomography angiography, MRI-T1W1, and contrast enhanced MRI-T1W1 image sequence scanning. The CT and MRI scanning data were collected and then imported into a Dextroscope imaging workstation, a virtual reality system that allows structures to be viewed stereoscopically. During preoperative assessment, typical images for each patient were chosen and printed out for use by the surgeons as references during surgery. Results All sellar tumor models clearly displayed bone, the internal carotid artery, circle of Willis and its branches, the optic nerve and chiasm, ventricular system, tumor, brain, soft tissue and adjacent structures. Depending on the location of the tumors, we simulated the transmononasal sphenoid sinus approach, transpterional approach, and other approaches. Eleven surgeons who used virtual reality models completed a survey questionnaire. Nine of the participants said that the virtual reality images were superior to other images but that other images needed to be used in combination with the virtual reality images. Conclusions The three-dimensional virtual reality models were helpful for individualized planning of surgery in the sellar region. Virtual reality appears to be promising as a valuable tool for sellar region surgery in the future. PMID:23190528

  14. Glaucomatous Progression in Series of Stereoscopic Photographs and Heidelberg Retina Tomograph Images

    PubMed Central

    O’Leary, Neil; Crabb, David P.; Mansberger, Steven L.; Fortune, Brad; Twa, Michael D.; Lloyd, Michael J.; Kotecha, Aachal; Garway-Heath, David F.; Cioffi, George A.; Johnson, Chris A.

    2011-01-01

    Objective To compare optic disc changes using automated analysis of Heidelberg retina tomography (HRT) images with assessments, by glaucoma specialists, of change in stereoscopic photographs. Methods Baseline and follow-up stereophotographs and corresponding HRT I series of 91 eyes from 56 patients were selected. The selection criteria were sufficiently long, good-quality HRT series (7 visits in 270 months of follow-up) and follow-up photographs contemporaneous with the final HRT image. Topographic change analysis (TCA), statistic image mapping (SIM), and linear regression of rim area (RALR) across time were applied to HRT series. Glaucomatous change determined from stereophotographs by expert observers was used as the reference standard. Results Expert observers identified 33 eyes (36%) as exhibiting glaucomatous change. Altering HRT progression criteria such that 36% of eyes progressed according to each method resulted in concordance between HRT methods and stereophotograph assessment of 54% for TCA, 65% for SIM, and 67% for RALR (Cohen K=0.05, 0.23, and 0.30, respectively). Receiver operating characteristic curves of the HRT analyses revealed poor precision of HRT analyses to predict stereophotograph-assessed change: areas under the curve were 0.61 for TCA, 0.62 for SIM, and 0.66 for RALR. Conclusions Statistical methods for detecting structural changes in HRT images exhibit only moderate agreement with each other and have poor agreement with expert-assessed change in optic disc stereophotographs. PMID:20457976

  15. InstantScope: a low-cost whole slide imaging system with instant focal plane detection

    PubMed Central

    Guo, Kaikai; Liao, Jun; Bian, Zichao; Heng, Xin; Zheng, Guoan

    2015-01-01

    We report the development of a high-throughput whole slide imaging (WSI) system by adapting a cost-effective optomechanical add-on kit to existing microscopes. Inspired by the phase detection concept in professional photography, we attached two pinhole-modulated cameras at the eyepiece ports for instant focal plane detection. By adjusting the positions of the pinholes, we can effectively change the view angle for the sample, and as such, we can use the translation shift of the two pinhole-modulated images to identify the optimal focal position. By using a small pinhole size, the focal-plane-detection range is on the order of millimeter, orders of magnitude longer than the objective’s depth of field. We also show that, by analyzing the phase correlation of the pinhole-modulated images, we can determine whether the sample contains one thin section, folded sections, or multiple layers separated by certain distances – an important piece of information prior to a detailed z scan. In order to achieve system automation, we deployed a low-cost programmable robotic arm to perform sample loading and $14 stepper motors to drive the microscope stage to perform x-y scanning. Using a 20X objective lens, we can acquire a 2 gigapixel image with 14 mm by 8 mm field of view in 90 seconds. The reported platform may find applications in biomedical research, telemedicine, and digital pathology. It may also provide new insights for the development of high-content screening instruments. PMID:26417493

  16. [Electronic eikonometer: Measurement tests displayed on stereoscopic screen].

    PubMed

    Bourdy, C; James, Y

    2016-05-01

    We propose the presentation on a stereoscopic screen of the electronic eikonometer tests intended for analysis and measurement of perceptual effects of binocular disparity. These tests, so-called "built-in magnification tests" are constructed according to the same principle as those of preceding eikonometers (disparity variation parameters being included in each test presentation, which allows, for test observation and measurements during the examination, the removing of any intermediate optical system). The images of these tests are presented separately to each eye, according to active or passive stereoscopic screen technology: (1) Ogle Spatial Test to measure aniseikonia; (2) Fixation Disparity test: binocular nonius; (3) retinal correspondence test evaluated by nonius horopter; (4) stereoscopic test using Julesz' random-dot stereograms (RDS). All of these tests, with their variable parameters included, are preprogrammed by means of an associated mini-computer. This new system (a single screen for the presentation of tests for the right eye and left eye) will be much simpler to reproduce and install for all practitioners interested in the functional exploration of binocular vision. We develop the suitable methodology adapted to each type of examination, as well as manipulations to be performed by the operator. We then recall the possibilities for reducing aniseikonia thanks to some theoretical studies previously performed by matrix calculation of the size of the retinal images for different types of eye (emmetropia, axial or conformation anisometropia, aphakia) and for different means of correction (glasses, contact lenses, implants). Software for achieving these different tests is available, on request, at this address: eiconometre.electronique@gmail.com. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Parallax scanning methods for stereoscopic three-dimensional imaging

    NASA Astrophysics Data System (ADS)

    Mayhew, Christopher A.; Mayhew, Craig M.

    2012-03-01

    Under certain circumstances, conventional stereoscopic imagery is subject to being misinterpreted. Stereo perception created from two static horizontally separated views can create a "cut out" 2D appearance for objects at various planes of depth. The subject volume looks three-dimensional, but the objects themselves appear flat. This is especially true if the images are captured using small disparities. One potential explanation for this effect is that, although three-dimensional perception comes primarily from binocular vision, a human's gaze (the direction and orientation of a person's eyes with respect to their environment) and head motion also contribute additional sub-process information. The absence of this information may be the reason that certain stereoscopic imagery appears "odd" and unrealistic. Another contributing factor may be the absence of vertical disparity information in a traditional stereoscopy display. Recently, Parallax Scanning technologies have been introduced, which provide (1) a scanning methodology, (2) incorporate vertical disparity, and (3) produce stereo images with substantially smaller disparities than the human interocular distances.1 To test whether these three features would improve the realism and reduce the cardboard cutout effect of stereo images, we have applied Parallax Scanning (PS) technologies to commercial stereoscopic digital cinema productions and have tested the results with a panel of stereo experts. These informal experiments show that the addition of PS information into the left and right image capture improves the overall perception of three-dimensionality for most viewers. Parallax scanning significantly increases the set of tools available for 3D storytelling while at the same time presenting imagery that is easy and pleasant to view.

  18. LED projection architectures for stereoscopic and multiview 3D displays

    NASA Astrophysics Data System (ADS)

    Meuret, Youri; Bogaert, Lawrence; Roelandt, Stijn; Vanderheijden, Jana; Avci, Aykut; De Smet, Herbert; Thienpont, Hugo

    2010-04-01

    LED-based projection systems have several interesting features: extended color-gamut, long lifetime, robustness and a fast turn-on time. However, the possibility to develop compact projectors remains the most important driving force to investigate LED projection. This is related to the limited light output of LED projectors that is a consequence of the relative low luminance of LEDs, compared to high intensity discharge lamps. We have investigated several LED projection architectures for the development of new 3D visualization displays. Polarization-based stereoscopic projection displays are often implemented using two identical projectors with passive polarizers at the output of their projection lens. We have designed and built a prototype of a stereoscopic projection system that incorporates the functionality of both projectors. The system uses high-resolution liquidcrystal- on-silicon light valves and an illumination system with LEDs. The possibility to add an extra LED illumination channel was also investigated for this optical configuration. Multiview projection displays allow the visualization of 3D images for multiple viewers without the need to wear special eyeglasses. Systems with large number of viewing zones have already been demonstrated. Such systems often use multiple projection engines. We have investigated a projection architecture that uses only one digital micromirror device and a LED-based illumination system to create multiple viewing zones. The system is based on the time-sequential modulation of the different images for each viewing zone and a special projection screen with micro-optical features. We analyzed the limitations of a LED-based illumination for the investigated stereoscopic and multiview projection systems and discuss the potential of a laser-based illumination.

  19. Perception of stereoscopic direct gaze: The effects of interaxial distance and emotional facial expressions.

    PubMed

    Hakala, Jussi; Kätsyri, Jari; Takala, Tapio; Häkkinen, Jukka

    2016-07-01

    Gaze perception has received considerable research attention due to its importance in social interaction. The majority of recent studies have utilized monoscopic pictorial gaze stimuli. However, a monoscopic direct gaze differs from a live or stereoscopic gaze. In the monoscopic condition, both eyes of the observer receive a direct gaze, whereas in live and stereoscopic conditions, only one eye receives a direct gaze. In the present study, we examined the implications of the difference between monoscopic and stereoscopic direct gaze. Moreover, because research has shown that stereoscopy affects the emotions elicited by facial expressions, and facial expressions affect the range of directions where an observer perceives mutual gaze-the cone of gaze-we studied the interaction effect of stereoscopy and facial expressions on gaze perception. Forty observers viewed stereoscopic images wherein one eye of the observer received a direct gaze while the other eye received a horizontally averted gaze at five different angles corresponding to five interaxial distances between the cameras in stimulus acquisition. In addition to monoscopic and stereoscopic conditions, the stimuli included neutral, angry, and happy facial expressions. The observers judged the gaze direction and mutual gaze of four lookers. Our results show that the mean of the directions received by the left and right eyes approximated the perceived gaze direction in the stereoscopic semidirect gaze condition. The probability of perceiving mutual gaze in the stereoscopic condition was substantially lower compared with monoscopic direct gaze. Furthermore, stereoscopic semidirect gaze significantly widened the cone of gaze for happy facial expressions.

  20. The compatibility of consumer DLP projectors with time-sequential stereoscopic 3D visualisation

    NASA Astrophysics Data System (ADS)

    Woods, Andrew J.; Rourke, Tegan

    2007-02-01

    A range of advertised "Stereo-Ready" DLP projectors are now available in the market which allow high-quality flickerfree stereoscopic 3D visualization using the time-sequential stereoscopic display method. The ability to use a single projector for stereoscopic viewing offers a range of advantages, including extremely good stereoscopic alignment, and in some cases, portability. It has also recently become known that some consumer DLP projectors can be used for timesequential stereoscopic visualization, however it was not well understood which projectors are compatible and incompatible, what display modes (frequency and resolution) are compatible, and what stereoscopic display quality attributes are important. We conducted a study to test a wide range of projectors for stereoscopic compatibility. This paper reports on the testing of 45 consumer DLP projectors of widely different specifications (brand, resolution, brightness, etc). The projectors were tested for stereoscopic compatibility with various video formats (PAL, NTSC, 480P, 576P, and various VGA resolutions) and video input connections (composite, SVideo, component, and VGA). Fifteen projectors were found to work well at up to 85Hz stereo in VGA mode. Twenty three projectors would work at 60Hz stereo in VGA mode.

  1. Microcomputer-based three-dimensional stereoscopic macromolecular graphics display.

    PubMed

    Shalloway, D; Sneddon, S F; Little, E K

    1988-03-01

    Software which permits an IBM AT and two IBM Professional Graphics Displays to be used to display high-quality three-dimensional space-filling stereoscopic images of macromolecules is described. Stereo image pairs generated on two screens are visually fused using a simple mirror system to provide binocular depth perception. Images are colored to identify atomic type, residue type, charge or hydrophobicity according to user-specified codes and can be rotated and rescaled. Macromolecules containing over 16,000 atoms can be rapidly drawn using Brookhaven Protein Data Bank or user-supplied coordinates.

  2. Stereoscopic high-speed imaging using additive colors

    PubMed Central

    Sankin, Georgy N.; Piech, David; Zhong, Pei

    2012-01-01

    An experimental system for digital stereoscopic imaging produced by using a high-speed color camera is described. Two bright-field image projections of a three-dimensional object are captured utilizing additive-color backlighting (blue and red). The two images are simultaneously combined on a two-dimensional image sensor using a set of dichromatic mirrors, and stored for off-line separation of each projection. This method has been demonstrated in analyzing cavitation bubble dynamics near boundaries. This technique may be useful for flow visualization and in machine vision applications. PMID:22559533

  3. Stereoscopic display technologies for FHD 3D LCD TV

    NASA Astrophysics Data System (ADS)

    Kim, Dae-Sik; Ko, Young-Ji; Park, Sang-Moo; Jung, Jong-Hoon; Shestak, Sergey

    2010-04-01

    Stereoscopic display technologies have been developed as one of advanced displays, and many TV industrials have been trying commercialization of 3D TV. We have been developing 3D TV based on LCD with LED BLU (backlight unit) since Samsung launched the world's first 3D TV based on PDP. However, the data scanning of panel and LC's response characteristics of LCD TV cause interference among frames (that is crosstalk), and this makes 3D video quality worse. We propose the method to reduce crosstalk by LCD driving and backlight control of FHD 3D LCD TV.

  4. Stereoscopic depth perception for robot vision: algorithms and architectures

    SciTech Connect

    Safranek, R.J.; Kak, A.C.

    1983-01-01

    The implementation of depth perception algorithms for computer vision is considered. In automated manufacturing, depth information is vital for tasks such as path planning and 3-d scene analysis. The presentation begins with a survey of computer algorithms for stereoscopic depth perception. The emphasis is on the Marr-Poggio paradigm of human stereo vision and its computer implementation. In addition, a stereo matching algorithm based on the relaxation labelling technique is examined. A computer architecture designed to efficiently implement stereo matching algorithms, an MIMD array interfaced to a global memory, is presented. 9 references.

  5. 3 CFR - Improving Availability of Relevant Executive Branch Records to the National Instant Criminal...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Records to the National Instant Criminal Background Check System Presidential Documents Other Presidential... National Instant Criminal Background Check System Memorandum for the Heads of Executive Departments and Agencies Since it became operational in 1998, the National Instant Criminal Background Check System...

  6. single-channel stereoscopic video imaging modality based on a transparent rotating deflector

    NASA Astrophysics Data System (ADS)

    Radfar, Edalat; Park, Jihoon; Jun, Eunkwon; Ha, Myungjin; Lee, Sangyeob; Yu, SungKon; Jang, Seul G.; Jung, Byungjo

    2015-03-01

    This paper introduces a stereoscopic video imaging modality based on a transparent rotating deflector (TRD). Sequential two-dimensional (2D) left and right images were obtained by rotating the TRD on a stepping motor synchronized with a complementary metal-oxide semiconductor camera, and the components of the imaging modality were controlled through general purpose input/output ports using a microcontroller unit. In this research, live stereoscopic videos were visualized on a personal computer by both active shutter 3D and passive polarization 3D methods. The imaging modality was characterized by evaluating the stereoscopic video image generation, rotation characteristics of the TRD. The level of 3D conception was estimated in terms of simplified human stereovision. The results show that singlechannel stereoscopic video imaging modality has the potential to become an economical compact stereoscopic device as the system components are amenable to miniaturization; and could be applied in a wide variety of fields.

  7. Depth reversals in stereoscopic displays driven by apparent size

    NASA Astrophysics Data System (ADS)

    Sacher, Gunnar; Hayes, Amy; Thornton, Ian M.; Sereno, Margaret E.; Malony, Allen D.

    1998-04-01

    In visual scenes, depth information is derived from a variety of monocular and binocular cues. When in conflict, a monocular cue is sometimes able to override the binocular information. We examined the accuracy of relative depth judgments in orthographic, stereoscopic displays and found that perceived relative size can override binocular disparity as a depth cue in a situation where the relative size information is itself generated from disparity information, not from retinal size difference. A size discrimination task confirmed the assumption that disparity information was perceived and used to generate apparent size differences. The tendency for the apparent size cue to override disparity information can be modulated by varying the strength of the apparent size cue. In addition, an analysis of reaction times provides supporting evidence for this novel depth reversal effect. We believe that human perception must be regarded as an important component of stereoscopic applications. Hence, if applications are to be effective and accurate, it is necessary to take into account the richness and complexity of the human visual perceptual system that interacts with them. We discuss implications of this and similar research for human performance in virtual environments, the design of visual presentations for virtual worlds, and the design of visualization tools.

  8. Virtual and stereoscopic anatomy: when virtual reality meets medical education.

    PubMed

    de Faria, Jose Weber Vieira; Teixeira, Manoel Jacobsen; de Moura Sousa Júnior, Leonardo; Otoch, Jose Pinhata; Figueiredo, Eberval Gadelha

    2016-11-01

    OBJECTIVE The authors sought to construct, implement, and evaluate an interactive and stereoscopic resource for teaching neuroanatomy, accessible from personal computers. METHODS Forty fresh brains (80 hemispheres) were dissected. Images of areas of interest were captured using a manual turntable and processed and stored in a 5337-image database. Pedagogic evaluation was performed in 84 graduate medical students, divided into 3 groups: 1 (conventional method), 2 (interactive nonstereoscopic), and 3 (interactive and stereoscopic). The method was evaluated through a written theory test and a lab practicum. RESULTS Groups 2 and 3 showed the highest mean scores in pedagogic evaluations and differed significantly from Group 1 (p < 0.05). Group 2 did not differ statistically from Group 3 (p > 0.05). Size effects, measured as differences in scores before and after lectures, indicate the effectiveness of the method. ANOVA results showed significant difference (p < 0.05) between groups, and the Tukey test showed statistical differences between Group 1 and the other 2 groups (p < 0.05). No statistical differences between Groups 2 and 3 were found in the practicum. However, there were significant differences when Groups 2 and 3 were compared with Group 1 (p < 0.05). CONCLUSIONS The authors conclude that this method promoted further improvement in knowledge for students and fostered significantly higher learning when compared with traditional teaching resources.

  9. Video retargeting for stereoscopic content under 3D viewing constraints

    NASA Astrophysics Data System (ADS)

    Chamaret, C.; Boisson, G.; Chevance, C.

    2012-03-01

    The imminent deployment of new devices such as TV, tablet, smart phone supporting stereoscopic display creates a need for retargeting the content. New devices bring their own aspect ratio and potential small screen size. Aspect ratio conversion becomes mandatory and an automatic solution will be of high value especially if it maximizes the visual comfort. Some issues inherent to 3D domain are considered in this paper: no vertical disparity, no object having negative disparity (outward perception) on the border of the cropping window. A visual attention model is applied on each view and provides saliency maps with most attractive pixels. Dedicated 3D retargeting correlates the 2D attention maps for each view as well as additional computed information to ensure the best cropping window. Specific constraints induced by 3D experience influence the retargeted window through the map computation presenting objects that should not be cropped. The comparison with original content of 2:35 ratio having black stripes provide limited 3D experience on TV screen, while the automatic cropping and exploitation of full screen show more immersive experience. The proposed system is fully automatic, ensures a good final quality without missing fundamental parts for the global understanding of the scene. Eye-tracking data recorded on stereoscopic content have been confronted to retargeted window in order to ensure that the most attractive areas are inside the final video.

  10. Spatial judgments with monoscopic and stereoscopic presentation of perspective displays.

    PubMed

    Yeh, Y Y; Silverstein, L D

    1992-10-01

    Spatial judgments with monoscopic and stereoscopic presentation of perspective displays were investigated in the present study. The stimulus configuration emulated a visual scene consisting of a volume of airspace above a ground reference plane. Two target symbols were situated at various positions in the space, and observers were instructed to identify the relative depth or altitude of the two symbols. Three viewing orientations (15, 45, or 90 deg elevation angle) were implemented in the perspective projection. In the monoscopic view, depth cues in size, brightness, occlusion, and linear perspective were provided in the format. In the stereoscopic view, binocular disparity was added along the line of sight from the center of projection to reinforce the relative depth in the visual scene. Results revealed that spatial judgments were affected by manipulation of the relative spatial positions of the two target symbols and by the interaction between relative position and viewing orientation. The addition of binocular disparity improved judgments of three-dimensional spatial relationships, and the enhancement was greater when monocular depth cues were less effective and/or ambiguous in recovering the three-dimensional spatial characteristics.

  11. Analysis of Performance of Stereoscopic-Vision Software

    NASA Technical Reports Server (NTRS)

    Kim, Won; Ansar, Adnan; Steele, Robert; Steinke, Robert

    2007-01-01

    A team of JPL researchers has analyzed stereoscopic vision software and produced a document describing its performance. This software is of the type used in maneuvering exploratory robotic vehicles on Martian terrain. The software in question utilizes correlations between portions of the images recorded by two electronic cameras to compute stereoscopic disparities, which, in conjunction with camera models, are used in computing distances to terrain points to be included in constructing a three-dimensional model of the terrain. The analysis included effects of correlation- window size, a pyramidal image down-sampling scheme, vertical misalignment, focus, maximum disparity, stereo baseline, and range ripples. Contributions of sub-pixel interpolation, vertical misalignment, and foreshortening to stereo correlation error were examined theoretically and experimentally. It was found that camera-calibration inaccuracy contributes to both down-range and cross-range error but stereo correlation error affects only the down-range error. Experimental data for quantifying the stereo disparity error were obtained by use of reflective metrological targets taped to corners of bricks placed at known positions relative to the cameras. For the particular 1,024-by-768-pixel cameras of the system analyzed, the standard deviation of the down-range disparity error was found to be 0.32 pixel.

  12. Influence of sonic noise on human stereoscopic depth perception.

    PubMed

    Hermann, E R; Hesse, C S; Hoyle, E R; Leopold, A C; Standard, J J

    1979-05-01

    Scientific establishment of the no-effect response to finite levels of exposure to a physical or chemical agent is indeed a rigorous exercise and is frequently controversial. In earlier research by Slutsky under direction of the senior author, a statistically significant increase in stereoscopic depth perception error was noted among 24 test subjects exposed to high intensity noise. Additional extensive research reported in this paper indicates that error in stereoscopic depth perception is not significantly altered by exposure to continuous white noise of short duration at levels ranging from 70 to 115 dBA. Furthernore, exposure of humans for periods of a few minutes to white noise in octave bands centered on 250 Hz, 1000 Hz, 4 kHz and 16 kHz at 115 dB does not affect their depth perception measured by the Howard-Dolman test. A comprehensive analysis of depth perception errors measured under noise exposure conditions (n = 4040) in comparison with those obtained under control conditions (n = 1430) produced a mean change in error of -0.38 mm, a statistically insignificant difference (p = 0.17). Even if such an error were attributable to high level noise, it should be noted that minus sign designates an improvement of depth perception in noise and that it is difficult to imagine visual tasks in which change in error of +/-0.38 mm at a distance of 6.0 meters is meaningful.

  13. Deep-level stereoscopic multiple traps of acoustic vortices

    NASA Astrophysics Data System (ADS)

    Li, Yuzhi; Guo, Gepu; Ma, Qingyu; Tu, Juan; Zhang, Dong

    2017-04-01

    Based on the radiation pattern of a planar piston transducer, the mechanisms underlying the generation of axially controllable deep-level stereoscopic multiple traps of acoustic vortices (AV) using sparse directional sources were proposed with explicit formulae. Numerical simulations for the axial and cross-sectional distributions of acoustic pressure and phase were conducted for various ka (product of the wave number and the radius of transducer) values at the frequency of 1 MHz. It was demonstrated that, for bigger ka, besides the main-AV (M-AV) generated by the main lobes of the sources, cone-shaped side-AV (S-AV) produced by the side lobes were closer to the source plane at a relatively lower pressure. Corresponding to the radiation angles of pressure nulls between the main lobe and the side lobes of the sources, vortex valleys with nearly pressure zero could be generated on the central axis to form multiple traps, based on Gor'kov potential theory. The number and locations of vortex valleys could be controlled accurately by the adjustment of ka. With the established eight-source AV generation system, the existence of the axially controllable multiple traps was verified by the measured M-AV and S-AVs as well as the corresponding vortex valleys. The favorable results provided the feasibility of deep-level stereoscopic control of AV and suggested potential application of multiple traps for particle manipulation in the area of biomedical engineering.

  14. Evaluation of stereoscopic display with visual function and interview

    NASA Astrophysics Data System (ADS)

    Okuyama, Fumio

    1999-05-01

    The influence of binocular stereoscopic (3D) television display on the human eye were compared with one of a 2D display, using human visual function testing and interviews. A 40- inch double lenticular display was used for 2D/3D comparison experiments. Subjects observed the display for 30 minutes at a distance 1.0 m, with a combination of 2D material and one of 3D material. The participants were twelve young adults. Main optometric test with visual function measured were visual acuity, refraction, phoria, near vision point, accommodation etc. The interview consisted of 17 questions. Testing procedures were performed just before watching, just after watching, and forty-five minutes after watching. Changes in visual function are characterized as prolongation of near vision point, decrease of accommodation and increase in phoria. 3D viewing interview results show much more visual fatigue in comparison with 2D results. The conclusions are: 1) change in visual function is larger and visual fatigue is more intense when viewing 3D images. 2) The evaluation method with visual function and interview proved to be very satisfactory for analyzing the influence of stereoscopic display on human eye.

  15. Matching and correlation computations in stereoscopic depth perception.

    PubMed

    Doi, Takahiro; Tanabe, Seiji; Fujita, Ichiro

    2011-03-02

    A fundamental task of the visual system is to infer depth by using binocular disparity. To encode binocular disparity, the visual cortex performs two distinct computations: one detects matched patterns in paired images (matching computation); the other constructs the cross-correlation between the images (correlation computation). How the two computations are used in stereoscopic perception is unclear. We dissociated their contributions in near/far discrimination by varying the magnitude of the disparity across separate sessions. For small disparity (0.03°), subjects performed at chance level to a binocularly opposite-contrast (anti-correlated) random-dot stereogram (RDS) but improved their performance with the proportion of contrast-matched (correlated) dots. For large disparity (0.48°), the direction of perceived depth reversed with an anti-correlated RDS relative to that for a correlated one. Neither reversed nor normal depth was perceived when anti-correlation was applied to half of the dots. We explain the decision process as a weighted average of the two computations, with the relative weight of the correlation computation increasing with the disparity magnitude. We conclude that matching computation dominates fine depth perception, while both computations contribute to coarser depth perception. Thus, stereoscopic depth perception recruits different computations depending on the disparity magnitude.

  16. Sound of a cup with and without instant coffee

    NASA Astrophysics Data System (ADS)

    Morrison, Andrew; Rossing, Thomas D.

    2002-05-01

    An empty coffee cup, like an ancient Chinese two-tone bell, emits two distinctly different tones, depending upon where it is tapped. When it is filled with hot water, and some instant coffee is added, however, a whole new set of sounds is heard when the cup is tapped. The pitch rises an octave or more as the foam clears due to the dramatic change in the speed of sound in the bubble-filled liquid. A similar, but smaller, effect was noted in beer by Bragg [The World of Sound (1968)] and in hot chocolate by Crawford [Am. J. Phys. (1982)]. We describe the modes of vibration in a coffee cup and the sound emitted by a coffee cup as filled with instant coffee as the bubble density changes.

  17. Scalable Fourier transform system for instantly structured illumination in lithography.

    PubMed

    Ye, Yan; Xu, Fengchuan; Wei, Guojun; Xu, Yishen; Pu, Donglin; Chen, Linsen; Huang, Zhiwei

    2017-05-15

    We report the development of a unique scalable Fourier transform 4-f system for instantly structured illumination in lithography. In the 4-f system, coupled with a 1-D grating and a phase retarder, the ±1st order of diffracted light from the grating serve as coherent incident sources for creating interference patterns on the image plane. By adjusting the grating and the phase retarder, the interference fringes with consecutive frequencies, as well as their orientations and phase shifts, can be generated instantly within a constant interference area. We demonstrate that by adapting this scalable Fourier transform system into lithography, the pixelated nano-fringe arrays with arbitrary frequencies and orientations can be dynamically produced in the photoresist with high variation resolution, suggesting its promising application for large-area functional materials based on space-variant nanostructures in lithography.

  18. Production of bioethanol and biodiesel using instant noodle waste.

    PubMed

    Yang, Xiaoguang; Lee, Ja Hyun; Yoo, Hah Young; Shin, Hyun Yong; Thapa, Laxmi Prasad; Park, Chulhwan; Kim, Seung Wook

    2014-08-01

    Instant noodle manufacturing waste was used as feedstock to convert it into two products, bioethanol and biodiesel. The raw material was pretreated to separate it into two potential feedstocks, starch residues and palm oil, for conversion to bioethanol and biodiesel, respectively. For the production of bioethanol, starch residues were converted into glucose by α-amylase and glucoamylase. To investigate the saccharification process of the pretreated starch residues, the optimal pretreatment conditions were determined. The bioethanol conversion reached 98.5 % of the theoretical maximum by Saccharomyces cerevisiae K35 fermentation after saccharification under optimized pretreatment conditions. Moreover, palm oil, isolated from the instant noodle waste, was converted into valuable biodiesel by use of immobilized lipase (Novozym 435). The effects of four categories of alcohol, oil-to-methanol ratio, reaction time, lipase concentration and water content on the conversion process were investigated. The maximum biodiesel conversion was 95.4 %.

  19. [Chemical characteristics and uses of instant corn flour II].

    PubMed

    Martínez, F; el-Dahs, A A

    1993-12-01

    The hydrothermal process using corn grits soaked in water at room temperature (28-30 degrees C) for 5 hours and steaming for 1 minute at 118 degrees C did not affect the proximal composition of the corn flour. However, the amino acid content was reduced approximately 18% (specially lysine and tryptophan). Vitamin and pigment contents were few affected. The characteristics of color and shelf life of corn flour were improved with the hydrothermal process. Tortillas prepared with instant corn flour showed better color and texture in comparison to the tortillas prepared by the conventional process. Polentas prepared with instant corn flour with 30 seconds of mixing showed better characteristics of flavor, odor, texture and required less preparation time than commercial polentas.

  20. Instant tough bonding of hydrogels for soft machines and electronics

    PubMed Central

    Wirthl, Daniela; Pichler, Robert; Drack, Michael; Kettlguber, Gerald; Moser, Richard; Gerstmayr, Robert; Hartmann, Florian; Bradt, Elke; Kaltseis, Rainer; Siket, Christian M.; Schausberger, Stefan E.; Hild, Sabine; Bauer, Siegfried; Kaltenbrunner, Martin

    2017-01-01

    Introducing methods for instant tough bonding between hydrogels and antagonistic materials—from soft to hard—allows us to demonstrate elastic yet tough biomimetic devices and machines with a high level of complexity. Tough hydrogels strongly attach, within seconds, to plastics, elastomers, leather, bone, and metals, reaching unprecedented interfacial toughness exceeding 2000 J/m2. Healing of severed ionic hydrogel conductors becomes feasible and restores function instantly. Soft, transparent multilayered hybrids of elastomers and ionic hydrogels endure biaxial strain with more than 2000% increase in area, facilitating soft transducers, generators, and adaptive lenses. We demonstrate soft electronic devices, from stretchable batteries, self-powered compliant circuits, and autonomous electronic skin for triggered drug delivery. Our approach is applicable in rapid prototyping and in delicate environments inaccessible for extended curing and cross-linking. PMID:28691092

  1. Managing the Risks and Rewards of Instant Messaging

    ERIC Educational Resources Information Center

    Goldsborough, Reid

    2004-01-01

    You probably think instant messaging (IM) as something teenagers do to chat up friends online, whether across the street or across the world. But IM has some buttoned-down business benefits, as well as some risks you may not be aware of. Unlike e-mail, in which you fire off messages to recipients who read them when they next check their in-box,…

  2. Negative stereoscopic sensation and its applications off-axis telescope fitting for any kind of stereo pictures

    NASA Astrophysics Data System (ADS)

    Wang, Jishao

    1994-08-01

    Shortening one's sight, a stereoscopic image can also be seen when he/she is watching a pair of pictures (a little different but interrelated with each other) directly. Such a way for watching stereoscopic pictures is better in many aspects than that of stretching sight. This method can be applied to stereoscopic photographs, stereo-movies and stereoscopic TVs, etc. An `off-axis telescope' designed may be used by those who can hardly shorten or stretch his/her sight directly at any position in an empty space for watching stereoscopic pictures.

  3. Emulsifiers and thickeners on extrusion-cooked instant rice product.

    PubMed

    Wang, Jin Peng; An, Hong Zhou; Jin, Zheng Yu; Xie, Zheng Jun; Zhuang, Hai Ning; Kim, Jin Moon

    2013-08-01

    Extrusion-cooked instant rice was prepared by optimizing the formulation with emulsifiers, glycerol monostearate (GMS), soybean lecithin (LC), and sodiumstearoyl lactylate (SSL), and thickeners, gum Arabic (GA), sodium alginate (SA), and sticky rice (SR). The emulsifiers addition caused increase of degree of gelatinization (DG), and decrease of water soluble carbohydrate (WSC), α-amylase sensitivity, water soluble index (WAI) and adhesive for extrudates, while the thickeners addition increased extrudates DG, bulk density (BD), WSC, α-amylase sensitivity, WAI, hydration rate (HR) and adhesiveness. Based on the data generated by a single additive at various levels, optimum formulation was obtained employing orthogonal matrix system with combination of the selected additives for extrusion cooking. Extrudates were evaluated for optimum hydration time followed by drying to prepare the finished product. Texture profile analysis and sensory evaluation indicate that quality of the finished product is equivalent to that of the round shaped rice and superior to a commercial instant rice product. This study also demonstrates possibility of value-added and versatile instant rice product development using broken rice.

  4. Instant cup of soup: design flaws increase risk of burns.

    PubMed

    Greenhalgh, David G; Bridges, Peggy; Coombs, Elena; Chapyak, Debbie; Doyle, William; O'Mara, Michael S; Palmieri, Tina L

    2006-01-01

    Prepackaged soups are a frequent cause of burn injury. We hypothesize that package design increases the risk for burn injury by affecting container stability. All pediatric scald burns caused by soup, between June 1997 and August 2004, were reviewed for burn and patient characteristics. Instant or "ready-to-eat" soups also were purchased. Safety statements and recommendations as to use of the microwave oven were documented. The height and the areas of the base and top were compared to the angle that a container would tip over on to its side. During the study period, 99 admissions and 80 outpatients were treated for burns caused by soup. Although the burn size was small (mean 5% TBSA) 22 patients required grafting. Of 13 different soups, 11 required the addition of hot water, and 2 were prepackaged for eating out of the container. Twelve containers had round bases and were tall and narrow, with one being shorter and rectangular. The measurements that correlated with the ease of tipping over were the base area, top area, and the ratio of height/base area. The most significant contributor to the ease of tipping over was height. Instant soups are packaged in containers that tend to be tall with a narrow base that predisposes them to being knocked over and spilled. Simple redesigning of instant soup packaging with a wider base and shorter height, along with the requirement for warnings about the risks of burns would reduce the frequency of soup burns.

  5. Development of a modular stereoscopic pre-visualisation and display framework

    NASA Astrophysics Data System (ADS)

    Kuchelmeister, Volker

    2011-03-01

    The increasing popularity for stereoscopic content in the entertainment industry and computer graphics applications and the availability of affordable capture and display systems is in contrast to the actual knowledge of underlying stereoscopic design principles and fundamental concepts. Content creators and educators inexperienced in stereoscopy require integrated, easy to use and flexible tools which can assist in the process of creating the three-dimensional "look" they are after within the limits of a comfortable viewing experience. The proposed framework in this paper, a custom stereoscopic export plug-in for the popular 3D modeling application Google Sketchup and a flexible stereoscopic format conversion and display engine, allows for stereoscopic previsualisation in near real-time in a format of choice. The user interface can recommend stereoscopic settings according to the scene, camera and display properties, calculates corresponding values according to manual entries but also leaves unrestricted control over all parameters. The display engine allows for different stereoscopic formats to be shown and saves the result in form of images with metadata for reference. Particular attention is put on usability, accessibility and tight integration.

  6. Cosmic origins: experiences making a stereoscopic 3D movie

    NASA Astrophysics Data System (ADS)

    Holliman, Nick

    2010-02-01

    Context: Stereoscopic 3D movies are gaining rapid acceptance commercially. In addition our previous experience with the short 3D movie "Cosmic Cookery" showed that there is great public interest in the presentation of cosmology research using this medium. Objective: The objective of the work reported in this paper was to create a three-dimensional stereoscopic movie describing the life of the Milky way galaxy. This was a technical and artistic exercise to take observed and simulated data from leading scientists and produce a short (six minute) movie that describes how the Milky Way was created and what happens in its future. The initial target audience was the visitors to the Royal Society's 2009 Summer Science Exhibition in central London, UK. The movie is also intended to become a presentation tool for scientists and educators following the exhibition. Apparatus: The presentation and playback systems used consisted of off-the shelf devices and software. The display platform for the Royal Society presentation was a RealD LP Pro switch used with a DLP projector to rear project a 4 metre diagonal image. The LP Pro enables the use of cheap disposable linearly polarising glasses so that the high turnover rate of the audience (every ten minutes at peak times) could be sustained without needing delays to clean the glasses. The playback system was a high speed PC with an external 8Tb RAID driving the projectors at 30Hz per eye, the Lightspeed DepthQ software was used to decode and generate the video stream. Results: A wide range of tools were used to render the image sequences, ranging from commercial to custom software. Each tool was able to produce a stream of 1080p images in stereo at 30fps. None of the rendering tools used allowed precise calibration of the stereo effect at render time and therefore all sequences were tuned extensively in a trial and error process until the stereo effect was acceptable and supported a comfortable viewing experience. Conclusion: We

  7. Digitizing Stereoscopic Optic Nerve Head Photographs for Storage and Viewing Using a Personal Computer

    PubMed Central

    Nesher, Ronit; Zacharopoulos, Ioannis; Assia, Ehud I.; Schuman, Joel S.

    2007-01-01

    Careful examination and monitoring of optic nerve head changes is essential in the treatment of patients with glaucoma. This often results in accumulation of numerous photographs and required appropriate storage space. A simple, inexpensive, and efficient means of storing and viewing stereoscopic optic nerve head photographs is described. Images were acquired with a fundus camera, on a color slide film. Slides were then scanned and digitized. A handheld stereoscope was used for stereoscopic viewing on a computer monitor. A scanning resolution of 300 dpi appeared optimal. At this resolution, the storage utilization was 16 kilobytes and the scanning time was 160 seconds per patient. PMID:16156151

  8. Digitizing stereoscopic optic nerve head photographs for storage and viewing using a personal computer.

    PubMed

    Nesher, Ronit; Zacharopoulos, Ioannis; Assia, Ehud I; Schuman, Joel S

    2005-01-01

    Careful examination and monitoring of optic nerve head changes is essential in the treatment of patients with glaucoma. This often results in accumulation of numerous photographs and required appropriate storage space. A simple, inexpensive, and efficient means of storing and viewing stereoscopic optic nerve head photographs is described. Images were acquired with a fundus camera, on a color slide film. Slides were then scanned and digitized. A handheld stereoscope was used for stereoscopic viewing on a computer monitor. A scanning resolution of 300 dpi appeared optimal. At this resolution, the storage utilization was 16 kilobytes and the scanning time was 160 seconds per patient.

  9. Head-coupled remote stereoscopic camera system for telepresence applications

    NASA Technical Reports Server (NTRS)

    Bolas, M. T.; Fisher, S. S.

    1990-01-01

    The Virtual Environment Workstation Project (VIEW) at NASA's Ames Research Center has developed a remotely controlled stereoscopic camera system that can be used for telepresence research and as a tool to develop and evaluate configurations for head-coupled visual systems associated with space station telerobots and remore manipulation robotic arms. The prototype camera system consists of two lightweight CCD video cameras mounted on a computer controlled platform that provides real-time pan, tilt, and roll control of the camera system in coordination with head position transmitted from the user. This paper provides an overall system description focused on the design and implementation of the camera and platform hardware configuration and the development of control software. Results of preliminary performance evaluations are reported with emphasis on engineering and mechanical design issues and discussion of related psychophysiological effects and objectives.

  10. Exocentric judgements in real environments and stereoscopic displays

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Tharp, Gregory K.; Grunwald, Arthur J.; Smith, Stephen

    1991-01-01

    Spatial direction errors during interpretation of perspective images, such as 3D map displays, may originate from misjudgment of the orientation of the viewing direction used to make the display. One source of these errors could be perceptual evidence of the display surface. Two experiments are reported in which the same judgment exocentric task was presented, but the cues to the picture surface were reduced or eliminated by presenting the task as a stereoscopic, virtual image or by a geometrically matched physical model. A theory developed to model exocentric direction errors on perspective displays has been fitted to the data from these two experiments. The parameters estimated from the fit in both experiments indicate that the subjects may be more correctly estimating the viewing direction than in ordinary perspective displays. Consequently, in some real world or stereo viewing conditions, errors in estimating the viewing direction are not likely to dominate exocentric direction errors.

  11. Stereoscopic, Force-Feedback Trainer For Telerobot Operators

    NASA Technical Reports Server (NTRS)

    Kim, Won S.; Schenker, Paul S.; Bejczy, Antal K.

    1994-01-01

    Computer-controlled simulator for training technicians to operate remote robots provides both visual and kinesthetic virtual reality. Used during initial stage of training; saves time and expense, increases operational safety, and prevents damage to robots by inexperienced operators. Computes virtual contact forces and torques of compliant robot in real time, providing operator with feel of forces experienced by manipulator as well as view in any of three modes: single view, two split views, or stereoscopic view. From keyboard, user specifies force-reflection gain and stiffness of manipulator hand for three translational and three rotational axes. System offers two simulated telerobotic tasks: insertion of peg in hole in three dimensions, and removal and insertion of drawer.

  12. Disparity modifications and the emotional effects of stereoscopic images

    NASA Astrophysics Data System (ADS)

    Kawai, Takashi; Atsuta, Daiki; Tomiyama, Yuya; Kim, Sanghyun; Morikawa, Hiroyuki; Mitsuya, Reiko; Häkkinen, Jukka

    2014-03-01

    This paper describes a study that focuses on disparity changes in emotional scenes of stereoscopic (3D) images, in which an examination of the effects on pleasant and arousal was carried out by adding binocular disparity to 2D images that evoke specific emotions, and applying disparity modification based on the disparity analysis of famous 3D movies. From the results of the experiment, for pleasant, a significant difference was found only for the main effect of the emotions. On the other hand, for arousal, there was a trend of increasing the evaluation values in the order 2D condition, 3D condition and 3D condition applied the disparity modification for happiness, surprise, and fear. This suggests the possibility that binocular disparity and the modification affect arousal.

  13. Visual perception and stereoscopic imaging: an artist's perspective

    NASA Astrophysics Data System (ADS)

    Mason, Steve

    2015-03-01

    This paper continues my 2014 February IS and T/SPIE Convention exploration into the relationship of stereoscopic vision and consciousness (90141F-1). It was proposed then that by using stereoscopic imaging people may consciously experience, or see, what they are viewing and thereby help make them more aware of the way their brains manage and interpret visual information. Environmental imaging was suggested as a way to accomplish this. This paper is the result of further investigation, research, and follow-up imaging. A show of images, that is a result of this research, allows viewers to experience for themselves the effects of stereoscopy on consciousness. Creating dye-infused aluminum prints while employing ChromaDepth® 3D glasses, I hope to not only raise awareness of visual processing but also explore the differences and similarities between the artist and scientist―art increases right brain spatial consciousness, not only empirical thinking, while furthering the viewer's cognizance of the process of seeing. The artist must abandon preconceptions and expectations, despite what the evidence and experience may indicate in order to see what is happening in his work and to allow it to develop in ways he/she could never anticipate. This process is then revealed to the viewer in a show of work. It is in the experiencing, not just from the thinking, where insight is achieved. Directing the viewer's awareness during the experience using stereoscopic imaging allows for further understanding of the brain's function in the visual process. A cognitive transformation occurs, the preverbal "left/right brain shift," in order for viewers to "see" the space. Using what we know from recent brain research, these images will draw from certain parts of the brain when viewed in two dimensions and different ones when viewed stereoscopically, a shift, if one is looking for it, which is quite noticeable. People who have experienced these images in the context of examining their own

  14. 3-D Target Location from Stereoscopic SAR Images

    SciTech Connect

    DOERRY,ARMIN W.

    1999-10-01

    SAR range-Doppler images are inherently 2-dimensional. Targets with a height offset lay over onto offset range and azimuth locations. Just which image locations are laid upon depends on the imaging geometry, including depression angle, squint angle, and target bearing. This is the well known layover phenomenon. Images formed with different aperture geometries will exhibit different layover characteristics. These differences can be exploited to ascertain target height information, in a stereoscopic manner. Depending on the imaging geometries, height accuracy can be on the order of horizontal position accuracies, thereby rivaling the best IFSAR capabilities in fine resolution SAR images. All that is required for this to work are two distinct passes with suitably different geometries from any plain old SAR.

  15. A new type of stereoscopic 3D mini-projector

    NASA Astrophysics Data System (ADS)

    Su, Ping; Ma, Jianshe; Li, Yan; Chen, Dingru; Li, Yi

    2011-11-01

    Mini-projectors based on LED illumination have already become a hotspot of projector industry, and time-sequential stereoscopic mini-projector has been developed. However, viewers to this type of 3D projector usually suffered from dark and flickering images caused by false synchronization of images and glasses, and the low transmittance of LC glasses. We propose a new type of polarized mini-3D-projector, which employs double LED illumination engines, and double LCoS panels. The optical model of the optical engine for the mini-3D-projector is built based on the measured optical qualities of the key optical elements. The large divergence angle is the main factor which affects disparity according to the simulated analysis. The first version of prototype is developed, which has low disparity (<5%) and performs comfortable viewing experience. This new type of 3D mini-projector has the advantages of the both conventional 3D projection technologies.

  16. Head-coupled remote stereoscopic camera system for telepresence applications

    NASA Technical Reports Server (NTRS)

    Bolas, M. T.; Fisher, S. S.

    1990-01-01

    The Virtual Environment Workstation Project (VIEW) at NASA's Ames Research Center has developed a remotely controlled stereoscopic camera system that can be used for telepresence research and as a tool to develop and evaluate configurations for head-coupled visual systems associated with space station telerobots and remore manipulation robotic arms. The prototype camera system consists of two lightweight CCD video cameras mounted on a computer controlled platform that provides real-time pan, tilt, and roll control of the camera system in coordination with head position transmitted from the user. This paper provides an overall system description focused on the design and implementation of the camera and platform hardware configuration and the development of control software. Results of preliminary performance evaluations are reported with emphasis on engineering and mechanical design issues and discussion of related psychophysiological effects and objectives.

  17. Type III source locations as inferred from stereoscopic observations

    NASA Astrophysics Data System (ADS)

    Boudjada, Mohammed Y.; Lammer, Helmut; Al-Haddad, Eimad; Hammoud, Muhamed; Galopeau, Patrick H. M.; Lichtenegger, Herbert

    2017-04-01

    We study the Type III solar bursts simultaneously recorded by radio experiments onboard Cassini, Ulysses and Wind. Those radio bursts cover a large frequency range from about 14 MHz to a few kHz. The corresponding source locations are mainly in the solar corona and the interplanetary medium. The empirical electron density models provide different distances depending on the emission mode, fundamental or harmonic. A real trouble arises due to the distance discrepancies, as inferred from the models. Also the Archimedean spiral trajectories of the electrons, at the origin of the Type III bursts, are another difficulty to correctly estimate the source locations. We show in our analysis that the stereoscopic observations are essential to reduce the source location inaccuracy. We finally discuss the relationship between the Type III beams, the emission modes and the source locations.

  18. Stereoscopic volume imaging on personal computers under Microsoft Windows

    NASA Astrophysics Data System (ADS)

    Weissman, Michael A.

    1995-03-01

    `Volume imaging' is the process of visualizing image data that exists on a grid in three- dimensions: at every point in the volume, a gray-level or color value is known. These image volumes usually result from building a `stack' from a sequence of cross-sectional views, such as those from CT, MRI, and confocal imaging. Stereoscopic viewing is a very effective way of viewing and analyzing these volumes. The stereo pair is constructed using ray projections. My objectives for this paper are three-fold: (1) To present a new way to view stereo images on a PC computer. (2) To demonstrate the ease-of-use and high image quality of the system using sample images from confocal microscopy. (3) To present preliminary results for projection image processing on a PC from CT and MRI image stacks.

  19. GIS Based Stereoscopic Visualization Technique for Weather Radar Data

    NASA Astrophysics Data System (ADS)

    Lim, S.; Jang, B. J.; Lee, K. H.; Lee, C.; Kim, W.

    2014-12-01

    As rainfall characteristic is more quixotic and localized, it is important to provide a prompt and accurate warning for public. To monitor localized heavy rainfall, a reliable disaster monitoring system with advanced remote observation technology and high-precision display system is needed. To advance even more accurate weather monitoring using weather radar, there have been growing concerns regarding the real-time changes of mapping radar observations on geographical coordinate systems along with the visualization and display methods of radar data based on spatial interpolation techniques and geographical information system (GIS). Currently, the method of simultaneously displaying GIS and radar data is widely used to synchronize the radar and ground systems accurately, and the method of displaying radar data in the 2D GIS coordinate system has been extensively used as the display method for providing weather information from weather radar. This paper proposes a realistic 3D weather radar data display technique with higher spatiotemporal resolution, which is based on the integration of 3D image processing and GIS interaction. This method is focused on stereoscopic visualization, while conventional radar image display works are based on flat or two-dimensional interpretation. Furthermore, using the proposed technique, the atmospheric change at each moment can be observed three-dimensionally at various geological locations simultaneously. Simulation results indicate that 3D display of weather radar data can be performed in real time. One merit of the proposed technique is that it can provide intuitive understanding of the influence of beam blockage by topography. Through an exact matching each 3D modeled radar beam with 3D GIS map, we can find out the terrain masked areas and accordingly it facilitates the precipitation correction from QPE underestimation caused by ground clutter filtering. It can also be expected that more accurate short-term forecasting will be

  20. Many-core computing for space-based stereoscopic imaging

    NASA Astrophysics Data System (ADS)

    McCall, Paul; Torres, Gildo; LeGrand, Keith; Adjouadi, Malek; Liu, Chen; Darling, Jacob; Pernicka, Henry

    The potential benefits of using parallel computing in real-time visual-based satellite proximity operations missions are investigated. Improvements in performance and relative navigation solutions over single thread systems can be achieved through multi- and many-core computing. Stochastic relative orbit determination methods benefit from the higher measurement frequencies, allowing them to more accurately determine the associated statistical properties of the relative orbital elements. More accurate orbit determination can lead to reduced fuel consumption and extended mission capabilities and duration. Inherent to the process of stereoscopic image processing is the difficulty of loading, managing, parsing, and evaluating large amounts of data efficiently, which may result in delays or highly time consuming processes for single (or few) processor systems or platforms. In this research we utilize the Single-Chip Cloud Computer (SCC), a fully programmable 48-core experimental processor, created by Intel Labs as a platform for many-core software research, provided with a high-speed on-chip network for sharing information along with advanced power management technologies and support for message-passing. The results from utilizing the SCC platform for the stereoscopic image processing application are presented in the form of Performance, Power, Energy, and Energy-Delay-Product (EDP) metrics. Also, a comparison between the SCC results and those obtained from executing the same application on a commercial PC are presented, showing the potential benefits of utilizing the SCC in particular, and any many-core platforms in general for real-time processing of visual-based satellite proximity operations missions.

  1. Wide-Field-of-View, High-Resolution, Stereoscopic Imager

    NASA Technical Reports Server (NTRS)

    Prechtl, Eric F.; Sedwick, Raymond J.

    2010-01-01

    A device combines video feeds from multiple cameras to provide wide-field-of-view, high-resolution, stereoscopic video to the user. The prototype under development consists of two camera assemblies, one for each eye. One of these assemblies incorporates a mounting structure with multiple cameras attached at offset angles. The video signals from the cameras are fed to a central processing platform where each frame is color processed and mapped into a single contiguous wide-field-of-view image. Because the resolution of most display devices is typically smaller than the processed map, a cropped portion of the video feed is output to the display device. The positioning of the cropped window will likely be controlled through the use of a head tracking device, allowing the user to turn his or her head side-to-side or up and down to view different portions of the captured image. There are multiple options for the display of the stereoscopic image. The use of head mounted displays is one likely implementation. However, the use of 3D projection technologies is another potential technology under consideration, The technology can be adapted in a multitude of ways. The computing platform is scalable, such that the number, resolution, and sensitivity of the cameras can be leveraged to improve image resolution and field of view. Miniaturization efforts can be pursued to shrink the package down for better mobility. Power savings studies can be performed to enable unattended, remote sensing packages. Image compression and transmission technologies can be incorporated to enable an improved telepresence experience.

  2. Misperceptions in Stereoscopic Displays: A Vision Science Perspective.

    PubMed

    Held, Robert T; Banks, Martin S

    2008-01-01

    3d shape and scene layout are often misperceived when viewing stereoscopic displays. For example, viewing from the wrong distance alters an object's perceived size and shape. It is crucial to understand the causes of such misperceptions so one can determine the best approaches for minimizing them. The standard model of misperception is geometric. The retinal images are calculated by projecting from the stereo images to the viewer's eyes. Rays are back-projected from corresponding retinal-image points into space and the ray intersections are determined. The intersections yield the coordinates of the predicted percept. We develop the mathematics of this model. In many cases its predictions are close to what viewers perceive. There are three important cases, however, in which the model fails: 1) when the viewer's head is rotated about a vertical axis relative to the stereo display (yaw rotation); 2) when the head is rotated about a forward axis (roll rotation); 3) when there is a mismatch between the camera convergence and the way in which the stereo images are displayed. In these cases, most rays from corresponding retinal-image points do not intersect, so the standard model cannot provide an estimate for the 3d percept. Nonetheless, viewers in these situations have coherent 3d percepts, so the visual system must use another method to estimate 3d structure. We show that the non-intersecting rays generate vertical disparities in the retinal images that do not arise otherwise. Findings in vision science show that such disparities are crucial signals in the visual system's interpretation of stereo images. We show that a model that incorporates vertical disparities predicts the percepts associated with improper viewing of stereoscopic displays. Improving the model of misperceptions will aid the design and presentation of 3d displays.

  3. Misperceptions in Stereoscopic Displays: A Vision Science Perspective

    PubMed Central

    Held, Robert T.; Banks, Martin S.

    2010-01-01

    3d shape and scene layout are often misperceived when viewing stereoscopic displays. For example, viewing from the wrong distance alters an object’s perceived size and shape. It is crucial to understand the causes of such misperceptions so one can determine the best approaches for minimizing them. The standard model of misperception is geometric. The retinal images are calculated by projecting from the stereo images to the viewer’s eyes. Rays are back-projected from corresponding retinal-image points into space and the ray intersections are determined. The intersections yield the coordinates of the predicted percept. We develop the mathematics of this model. In many cases its predictions are close to what viewers perceive. There are three important cases, however, in which the model fails: 1) when the viewer’s head is rotated about a vertical axis relative to the stereo display (yaw rotation); 2) when the head is rotated about a forward axis (roll rotation); 3) when there is a mismatch between the camera convergence and the way in which the stereo images are displayed. In these cases, most rays from corresponding retinal-image points do not intersect, so the standard model cannot provide an estimate for the 3d percept. Nonetheless, viewers in these situations have coherent 3d percepts, so the visual system must use another method to estimate 3d structure. We show that the non-intersecting rays generate vertical disparities in the retinal images that do not arise otherwise. Findings in vision science show that such disparities are crucial signals in the visual system’s interpretation of stereo images. We show that a model that incorporates vertical disparities predicts the percepts associated with improper viewing of stereoscopic displays. Improving the model of misperceptions will aid the design and presentation of 3d displays. PMID:24683290

  4. Clinical Assessment of Stereoacuity and 3-D Stereoscopic Entertainment.

    PubMed

    Tidbury, Laurence P; Black, Robert H; O'Connor, Anna R

    2015-01-01

    The perception of compelling depth is often reported in individuals where no clinically measurable stereoacuity is apparent. We aim to investigate the potential cause of this finding by varying the amount of stereopsis available to the subject, and assessing their perception of depth viewing 3-D video clips and a Nintendo 3DS. Monocular blur was used to vary interocular VA difference, consequently creating 4 levels of measurable binocular deficit from normal stereoacuity to suppression. Stereoacuity was assessed at each level using the TNO, Preschool Randot®, Frisby, the FD2, and Distance Randot®. Subjects also completed an object depth identification task using the Nintendo 3DS, a static 3DTV stereoacuity test, and a 3-D perception rating task of 6 video clips. As intraocular VA differences increased, stereoacuity of the 57 subjects (aged 16-62 years) decreased (eg, 110", 280", 340", and suppression). The ability to correctly identify depth on the Nintendo 3DS remained at 100% until suppression of one eye occurred. The perception of a compelling 3-D effect when viewing the video clips was rated high until suppression of one eye occurred, where the 3-D effect was still reported as fairly evident. If an individual has any level of measurable stereoacuity, the perception of 3-D when viewing stereoscopic entertainment is present. The presence of motion in stereoscopic video appears to provide cues to depth, where static cues are not sufficient. This suggests there is a need for a dynamic test of stereoacuity to be developed, to allow fully informed patient management decisions to be made.

  5. Clinical Assessment of Stereoacuity and 3-D Stereoscopic Entertainment

    PubMed Central

    Tidbury, Laurence P.; Black, Robert H.; O’Connor, Anna R.

    2015-01-01

    Abstract Background/Aims: The perception of compelling depth is often reported in individuals where no clinically measurable stereoacuity is apparent. We aim to investigate the potential cause of this finding by varying the amount of stereopsis available to the subject, and assessing their perception of depth viewing 3-D video clips and a Nintendo 3DS. Methods: Monocular blur was used to vary interocular VA difference, consequently creating 4 levels of measurable binocular deficit from normal stereoacuity to suppression. Stereoacuity was assessed at each level using the TNO, Preschool Randot®, Frisby, the FD2, and Distance Randot®. Subjects also completed an object depth identification task using the Nintendo 3DS, a static 3DTV stereoacuity test, and a 3-D perception rating task of 6 video clips. Results: As intraocular VA differences increased, stereoacuity of the 57 subjects (aged 16–62 years) decreased (eg, 110”, 280”, 340”, and suppression). The ability to correctly identify depth on the Nintendo 3DS remained at 100% until suppression of one eye occurred. The perception of a compelling 3-D effect when viewing the video clips was rated high until suppression of one eye occurred, where the 3-D effect was still reported as fairly evident. Conclusion: If an individual has any level of measurable stereoacuity, the perception of 3-D when viewing stereoscopic entertainment is present. The presence of motion in stereoscopic video appears to provide cues to depth, where static cues are not sufficient. This suggests there is a need for a dynamic test of stereoacuity to be developed, to allow fully informed patient management decisions to be made. PMID:26669421

  6. Rejuvenating Hydrator: Restoring Epidermal Hyaluronic Acid Homeostasis With Instant Benefits.

    PubMed

    Narurkar, Vic A; Fabi, Sabrina G; Bucay, Vivian W; Tedaldi, Ruth; Downie, Jeanine B; Zeichner, Joshua A; Butterwick, Kimberly; Taub, Amy; Kadoya, Kuniko; Makino, Elizabeth T; Mehta, Rahul C; Vega, Virginia L

    2016-01-01

    Skin aging is a combination of multifactorial mechanisms that are not fully understood. Intrinsic and extrinsic factors modulate skin aging, activating distinctive processes that share similar molecular pathways. One of the main characteristics of youthful skin is its large capacity to retain water, and this decreases significantly as we age. A key molecule involved in maintaining skin hydration is hyaluronic acid (HA). Concentration of HA in the skin is determined by the complex balance between its synthesis, deposition, association with cellular structures, and degradation. HA bio-equivalency and bio-compatibility have been fundamental in keeping this macromolecule as the favorite of the skincare industry for decades. Scientific evidence now shows that topically applied HA is unable to penetrate the skin and is rapidly degraded on the skin surface. SkinMedica's HA5 Rejuvenating Hydrator (SkinMedica Inc., an Allergan company, Irvine, CA) promotes restoration of endogenous epidermal HA homeostasis and provides instant smoothing and hydration of the skin. These dual benefits are accomplished through the combination of 2 breakthrough technologies: 1) a unique blend of actives powered by SkinMedica proprietary flower-derived stem cell extract that restores the endogenous production of HA; and 2) a proprietary mix of 5 HA forms that plump the skin, decreasing the appearance of fine lines/wrinkles. Pre-clinical studies demonstrated that HA5 induces expression of key epidermal differentiation and barrier markers as well as epidermal HA synthases. A decrease expression of hyaluronidases was also observed upon HA5 application. Initial clinical studies showed that within 15 minutes of application, HA5 instantly improves the appearance of fine lines/wrinkles and skin hydration. Subjects that continue using HA5 (for 8 weeks) demonstrated significant improvements in fine lines/wrinkles, tactile roughness, and skin hydration. In summary, the blend of these 2 key technologies

  7. Development of an instant coffee enriched with chlorogenic acids.

    PubMed

    Corso, Marinês Paula; Vignoli, Josiane Alessandra; Benassi, Marta de Toledo

    2016-03-01

    The objective of this study was to present possible formulations for an instant coffee product enriched with chlorogenic acids for the Brazilian market. Formulations were prepared with different concentrations of freeze dried extracts of green Coffea canephora beans (G) added to freeze dried extracts of roasted Coffea arabica (A) and Coffea canephora (C). Medium (M) and dark (D) roasting degrees instant coffee were produced (AM, AD, CM and CD) to obtain four formulations with green extract addition (AMG, ADG, CMG and CDG). Chlorogenic acids were determined by HPLC, with average contents of 7.2 %. Roasted extracts and formulations were evaluated for 5-CQA and caffeine contents (by HPLC), browned compounds (absorbance 420 nm), and antioxidant activity (ABTS and Folin). Coffee brews of the four formulations were also assessed in a lab-scale test by 42 consumers for acceptance of the color, aroma, flavor and body, overall acceptance and purchase intent, using a 10 cm hybrid scale. The formulations obtained acceptance scores of 6.6 and 7.7 for all attributes, thus they were equally acceptable. Greater purchase intent was observed for ADG, CDG and CMG (6.9) in comparison to AMG (6.1). The formulations had, on average, 2.5 times more 5-CQA than the average obtained from conventional commercial instant coffees. In addition to being more economically viable, the formulations developed with C. canephora (CDG and CMG) showed greater antioxidant potential (32.5 g of Trolox/100 g and 13.8 g of gallic acid equivalent/100 g) due to a balance in the amount of bioactive compounds.

  8. Controllable liquid crystal gratings for an adaptive 2D/3D auto-stereoscopic display

    NASA Astrophysics Data System (ADS)

    Zhang, Y. A.; Jin, T.; He, L. C.; Chu, Z. H.; Guo, T. L.; Zhou, X. T.; Lin, Z. X.

    2017-02-01

    2D/3D switchable, viewpoint controllable and 2D/3D localizable auto-stereoscopic displays based on controllable liquid crystal gratings are proposed in this work. Using the dual-layer staggered structure on the top substrate and bottom substrate as driven electrodes within a liquid crystal cell, the ratio between transmitting region and shielding region can be selectively controlled by the corresponding driving circuit, which indicates that 2D/3D switch and 3D video sources with different disparity images can reveal in the same auto-stereoscopic display system. Furthermore, the controlled region in the liquid crystal gratings presents 3D model while other regions maintain 2D model in the same auto-stereoscopic display by the corresponding driving circuit. This work demonstrates that the controllable liquid crystal gratings have potential applications in the field of auto-stereoscopic display.

  9. Stereoscopic displays and applications; Proceedings of the Meeting, Santa Clara, CA, Feb. 12-14, 1990

    NASA Technical Reports Server (NTRS)

    Merritt, John O. (Editor); Fisher, Scott S. (Editor)

    1990-01-01

    The present conference discusses topics in the fields of stereoscopic displays' user interfaces, three-dimensional (TD) visualization, novel TD displays, and applications of stereoscopic displays. Attention is given to TD cockpit displays, novel computational control techniques for stereo TD displays, characterization of higher-dimensional presentation techniques, volume visualization on a stereoscopic display, and stereoscopic displays for terrain-data base visualization. Also discussed are the experimental design of cyberspaces, a volumetric environment for interactive design of three-dimensional objects, videotape recording of TD TV images, remote manipulator tasks rendered possible by stereo TV, TD endoscopy based on alternating-frame technology, and advancements in computer-generated barrier-strip autostereography.

  10. High-Speed Generation of Illumination Spectra for a Stereoscopic Endoscope

    NASA Technical Reports Server (NTRS)

    Fritz, Eric

    2011-01-01

    Traditional stereoscopic vision (3D) is achieved through use of two separate cameras, arranged to emulate human eyes. This method works well on most projects, but becomes impractical on small scale designs, such as surgical endoscopes. This project is focused on developing a stereoscopic endoscope, using a single camera and Conjugated Multiple?Bandpass Filters (CMBF) to produce stereoscopic vision. Each half of filter is built to allow a distinct spectrum to pass through, while blocking the complimentary spectrum. A system with complimentary filters can produce stereoscopic images. To accomplish this, the light must be filtered at the source to match the filters at the camera. Additionally, the light source and camera must be synchronized in a way that each image will show only one filter spectrum. In this paper, I will describe the design and characterization of the prototype electro?optical system, including optical throughput measurements and video produced using this method.

  11. Analysis of brain activity and response during monoscopic and stereoscopic visualization

    NASA Astrophysics Data System (ADS)

    Calore, Enrico; Folgieri, Raffaella; Gadia, Davide; Marini, Daniele

    2012-03-01

    Stereoscopic visualization in cinematography and Virtual Reality (VR) creates an illusion of depth by means of two bidimensional images corresponding to different views of a scene. This perceptual trick is used to enhance the emotional response and the sense of presence and immersivity of the observers. An interesting question is if and how it is possible to measure and analyze the level of emotional involvement and attention of the observers during a stereoscopic visualization of a movie or of a virtual environment. The research aims represent a challenge, due to the large number of sensorial, physiological and cognitive stimuli involved. In this paper we begin this research by analyzing possible differences in the brain activity of subjects during the viewing of monoscopic or stereoscopic contents. To this aim, we have performed some preliminary experiments collecting electroencephalographic (EEG) data of a group of users using a Brain- Computer Interface (BCI) during the viewing of stereoscopic and monoscopic short movies in a VR immersive installation.

  12. The Portable Instant Display and Analysis Spectrometer (PIDAS)

    NASA Technical Reports Server (NTRS)

    Goetz, Alexander F. H.

    1987-01-01

    A field spectrometer covering the range 0.4 to 2.5 microns was developed that acquires spectra in 2 seconds at 872 points within the spectrum. The Portable Instant Display and Analysis Spectrometer (PIDAS) can acquire spectra every 8 seconds and stores up to 288 spectra in bubble memory. A hand held display unit allows for display of the current spectrum acquired and superimposed on one of 128 permanently stored library spectra. PIDAS represents a major advance in the technology of field spectral data acquisition and for the first time makes possible the acquisition of enough spectra to characterize the mean and intraclass variance within a LANDSAT MSS or TM pixel.

  13. Electromagnetic nucleon form factors in instant and point form

    SciTech Connect

    Melde, T.; Berger, K.; Plessas, W.; Wagenbrunn, R. F.; Canton, L.

    2007-10-01

    We present a study of the electromagnetic structure of the nucleons with constituent quark models in the framework of relativistic quantum mechanics. In particular, we address the construction of spectator-model currents in the instant and point forms. Corresponding results for the elastic nucleon electromagnetic form factors as well as charge radii and magnetic moments are presented. We also compare results obtained by different realistic nucleon wave functions stemming from alternative constituent quark models. Finally, we discuss the theoretical uncertainties that reside in the construction of spectator-model transition operators.

  14. Holographic instant conformal symmetry breaking by colliding conical defects

    NASA Astrophysics Data System (ADS)

    Ageev, D. S.; Aref'eva, I. Ya.

    2016-12-01

    We study instant conformal symmetry breaking as a holographic effect of ultrarelativistic particles moving in the AdS3 space-time. We give a qualitative picture of this effect based on calculating the two-point correlation functions and the entanglement entropy of the corresponding boundary theory. We show that in the geodesic approximation, because of gravitational lensing of the geodesics, the ultrarelativistic massless defect produces a zone structure for correlators with broken conformal invariance. At the same time, the holographic entanglement entropy also exhibits a transition to nonconformal behavior. Two colliding massless defects produce a more diverse zone structure for correlators and the entanglement entropy.

  15. Augmented reality to the rescue of the minimally invasive surgeon. The usefulness of the interposition of stereoscopic images in the Da Vinci™ robotic console.

    PubMed

    Volonté, Francesco; Buchs, Nicolas C; Pugin, François; Spaltenstein, Joël; Schiltz, Boris; Jung, Minoa; Hagen, Monika; Ratib, Osman; Morel, Philippe

    2013-09-01

    Computerized management of medical information and 3D imaging has become the norm in everyday medical practice. Surgeons exploit these emerging technologies and bring information previously confined to the radiology rooms into the operating theatre. The paper reports the authors' experience with integrated stereoscopic 3D-rendered images in the da Vinci surgeon console. Volume-rendered images were obtained from a standard computed tomography dataset using the OsiriX DICOM workstation. A custom OsiriX plugin was created that permitted the 3D-rendered images to be displayed in the da Vinci surgeon console and to appear stereoscopic. These rendered images were displayed in the robotic console using the TilePro multi-input display. The upper part of the screen shows the real endoscopic surgical field and the bottom shows the stereoscopic 3D-rendered images. These are controlled by a 3D joystick installed on the console, and are updated in real time. Five patients underwent a robotic augmented reality-enhanced procedure. The surgeon was able to switch between the classical endoscopic view and a combined virtual view during the procedure. Subjectively, the addition of the rendered images was considered to be an undeniable help during the dissection phase. With the rapid evolution of robotics, computer-aided surgery is receiving increasing interest. This paper details the authors' experience with 3D-rendered images projected inside the surgical console. The use of this intra-operative mixed reality technology is considered very useful by the surgeon. It has been shown that the usefulness of this technique is a step toward computer-aided surgery that will progress very quickly over the next few years. Copyright © 2012 John Wiley & Sons, Ltd.

  16. Clinically Normal Stereopsis Does Not Ensure Performance Benefit from Stereoscopic 3D Depth Cues

    DTIC Science & Technology

    2014-10-28

    Stereopsis, Binocular Vision, Optometry, Depth Perception , 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 16...Binocular Vision, Optometry, Depth Perception , 3D vision, 3D human factors, Stereoscopic displays, S3D, Virtual environment 1 Distribution A: Approved...disparities (up to ~20 arc min) that are fused into a single binocular percept when presented briefly, and that result in increased perceptions of depth

  17. Acquisition of Stereoscopic Particle Image Velocimetry System for Investigation of Unsteady Flows

    DTIC Science & Technology

    2016-04-30

    SECURITY CLASSIFICATION OF: The objective of the project titled “Acquisition of Stereoscopic Particle Image Velocimetry (S-PIV) System for...Distribution Unlimited UU UU UU UU 30-04-2016 1-Feb-2015 31-Jan-2016 Final Report: Acquisition of Stereoscopic Particle Image Velocimetry System For...ADDRESS (ES) U.S. Army Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 Particle Image Velocimetry REPORT DOCUMENTATION PAGE 11

  18. Operation and maintenance manual for the high resolution stereoscopic video camera system (HRSVS) system 6230

    SciTech Connect

    Pardini, A.F., Westinghouse Hanford

    1996-07-16

    The High Resolution Stereoscopic Video Cameral System (HRSVS),system 6230, is a stereoscopic camera system that will be used as an end effector on the LDUA to perform surveillance and inspection activities within Hanford waste tanks. It is attached to the LDUA by means of a Tool Interface Plate (TIP), which provides a feed through for all electrical and pneumatic utilities needed by the end effector to operate.

  19. Tele-transmission of stereoscopic images of the optic nerve head in glaucoma via Internet.

    PubMed

    Bergua, Antonio; Mardin, Christian Y; Horn, Folkert K

    2009-06-01

    The objective was to describe an inexpensive system to visualize stereoscopic photographs of the optic nerve head on computer displays and to transmit such images via the Internet for collaborative research or remote clinical diagnosis in glaucoma. Stereoscopic images of glaucoma patients were digitized and stored in a file format (joint photographic stereoimage [jps]) containing all three-dimensional information for both eyes on an Internet Web site (www.trizax.com). The size of jps files was between 0.4 to 1.4 MB (corresponding to a diagonal stereo image size between 900 and 1400 pixels) suitable for Internet protocols. A conventional personal computer system equipped with wireless stereoscopic LCD shutter glasses and a CRT-monitor with high refresh rate (120 Hz) can be used to obtain flicker-free stereo visualization of true-color images with high resolution. Modern thin-film transistor-LCD displays in combination with inexpensive red-cyan goggles achieve stereoscopic visualization with the same resolution but reduced color quality and contrast. The primary aim of our study was met to transmit stereoscopic images via the Internet. Additionally, we found that with both stereoscopic visualization techniques, cup depth, neuroretinal rim shape, and slope of the inner wall of the optic nerve head, can be qualitatively better perceived and interpreted than with monoscopic images. This study demonstrates high-quality and low-cost Internet transmission of stereoscopic images of the optic nerve head from glaucoma patients. The technique allows exchange of stereoscopic images and can be applied to tele-diagnostic and glaucoma research.

  20. Depth Perception and the History of Three-Dimensional Art: Who Produced the First Stereoscopic Images?

    PubMed Central

    2017-01-01

    The history of the expression of three-dimensional structure in art can be traced from the use of occlusion in Palaeolithic cave paintings, through the use of shadow in classical art, to the development of perspective during the Renaissance. However, the history of the use of stereoscopic techniques is controversial. Although the first undisputed stereoscopic images were presented by Wheatstone in 1838, it has been claimed that two sketches by Jacopo Chimenti da Empoli (c. 1600) can be to be fused to yield an impression of stereoscopic depth, while others suggest that Leonardo da Vinci’s Mona Lisa is the world’s first stereogram. Here, we report the first quantitative study of perceived depth in these works, in addition to more recent works by Salvador Dalí. To control for the contribution of monocular depth cues, ratings of the magnitude and coherence of depth were recorded for both stereoscopic and pseudoscopic presentations, with a genuine contribution of stereoscopic cues revealed by a difference between these scores. Although effects were clear for Wheatstone and Dalí’s images, no such effects could be found for works produced earlier. As such, we have no evidence to reject the conventional view that the first producer of stereoscopic imagery was Sir Charles Wheatstone. PMID:28203349

  1. Eliciting steady-state visual evoked potentials by means of stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Calore, Enrico; Gadia, Davide; Marini, Daniele

    2014-03-01

    Brain-Computer Interfaces (BCIs) provide users communication and control capabilities by analyzing their brain activity. A technique to implement BCIs, used recently also in Virtual Reality (VR) environments, is based on the Steady State Visual Evoked Potentials (SSVEPs) detection. Exploiting the SSVEP response, BCIs could be implemented showing targets flickering at different frequencies and detecting which is gazed by the observer analyzing her/his electroencephalographic (EEG) signals. In this work, we evaluate the use of stereoscopic displays for the presentation of SSVEP eliciting stimuli, comparing their effectiveness between monoscopic and stereoscopic stimuli. Moreover we propose a novel method to elicit SSVEP responses exploiting the stereoscopic displays capability of presenting dichoptic stimuli. We have created an experimental scene to present flickering stimuli on an active stereoscopic display, obtaining reliable control of the targets' frequency independently for the two stereo views. Using an EEG acquisition device, we analyzed the SSVEP responses from a group of subjects. From the preliminary results, we got evidence that stereoscopic displays represent valid devices for the presentation of SSVEP stimuli. Moreover, the use of different flickering frequencies for the two views of a single stimulus proved to elicit non-linear interactions between the stimulation frequencies, clearly visible in the EEG signal. This suggests interesting applications for SSVEP-based BCIs in VR environments able to overcome some limitations imposed by the refresh frequency of standard displays, but also the use of commodity stereoscopic displays to implement binocular rivalry experiments.

  2. A Review on Stereoscopic 3D: Home Entertainment for the Twenty First Century

    NASA Astrophysics Data System (ADS)

    Karajeh, Huda; Maqableh, Mahmoud; Masa'deh, Ra'ed

    2014-12-01

    In the last few years, stereoscopic developed very rapidly and employed in many different fields such as entertainment. Due to the importance of entertainment aspect of stereoscopic 3D (S3D) applications, a review of the current state of S3D development in entertainment technology is conducted. In this paper, a novel survey of the stereoscopic entertainment aspects is presented by discussing the significant development of a 3D cinema, the major development of 3DTV, the issues related to 3D video content and 3D video games. Moreover, we reviewed some problems that can be caused in the viewers' visual system from watching stereoscopic contents. Some stereoscopic viewers are not satisfied as they are frustrated from wearing glasses, have visual fatigue, complain from unavailability of 3D contents, and/or complain from some sickness. Therefore, we will discuss stereoscopic visual discomfort and to what extend the viewer will have an eye fatigue while watching 3D contents or playing 3D games. The suggested solutions in the literature for this problem are discussed.

  3. Recording stereoscopic 3D neurosurgery with a head-mounted 3D camera system.

    PubMed

    Lee, Brian; Chen, Brian R; Chen, Beverly B; Lu, James Y; Giannotta, Steven L

    2015-06-01

    Stereoscopic three-dimensional (3D) imaging can present more information to the viewer and further enhance the learning experience over traditional two-dimensional (2D) video. Most 3D surgical videos are recorded from the operating microscope and only feature the crux, or the most important part of the surgery, leaving out other crucial parts of surgery including the opening, approach, and closing of the surgical site. In addition, many other surgeries including complex spine, trauma, and intensive care unit procedures are also rarely recorded. We describe and share our experience with a commercially available head-mounted stereoscopic 3D camera system to obtain stereoscopic 3D recordings of these seldom recorded aspects of neurosurgery. The strengths and limitations of using the GoPro(®) 3D system as a head-mounted stereoscopic 3D camera system in the operating room are reviewed in detail. Over the past several years, we have recorded in stereoscopic 3D over 50 cranial and spinal surgeries and created a library for education purposes. We have found the head-mounted stereoscopic 3D camera system to be a valuable asset to supplement 3D footage from a 3D microscope. We expect that these comprehensive 3D surgical videos will become an important facet of resident education and ultimately lead to improved patient care.

  4. Depth Perception and the History of Three-Dimensional Art: Who Produced the First Stereoscopic Images?

    PubMed

    Brooks, Kevin R

    2017-01-01

    The history of the expression of three-dimensional structure in art can be traced from the use of occlusion in Palaeolithic cave paintings, through the use of shadow in classical art, to the development of perspective during the Renaissance. However, the history of the use of stereoscopic techniques is controversial. Although the first undisputed stereoscopic images were presented by Wheatstone in 1838, it has been claimed that two sketches by Jacopo Chimenti da Empoli (c. 1600) can be to be fused to yield an impression of stereoscopic depth, while others suggest that Leonardo da Vinci's Mona Lisa is the world's first stereogram. Here, we report the first quantitative study of perceived depth in these works, in addition to more recent works by Salvador Dalí. To control for the contribution of monocular depth cues, ratings of the magnitude and coherence of depth were recorded for both stereoscopic and pseudoscopic presentations, with a genuine contribution of stereoscopic cues revealed by a difference between these scores. Although effects were clear for Wheatstone and Dalí's images, no such effects could be found for works produced earlier. As such, we have no evidence to reject the conventional view that the first producer of stereoscopic imagery was Sir Charles Wheatstone.

  5. Instant well-log inversion with a parallel computer

    SciTech Connect

    Kimminau, S.J.; Trivedi, H.

    1993-08-01

    Well-log analysis requires several vectors of input data to be inverted with a physical model that produces more vectors of output data. The problem is inherently suited to either vectorization or parallelization. PLATO (parallel log analysis, timely output) is a research prototype system that uses a parallel architecture computer with memory-mapped graphics to invert vector data and display the result rapidly. By combining this high-performance computing and display system with a graphical user interface, the analyst can interact with the system in real time'' and can visualize the result of changing parameters on up to 1,000 levels of computed volumes and reconstructed logs. It is expected that such instant'' inversion will remove the main disadvantages frequently cited for simultaneous analysis methods, namely difficulty in assessing sensitivity to different parameters and slow output response. Although the prototype system uses highly specific features of a parallel processor, a subsequent version has been implemented on a conventional (Serial) workstation with less performance but adequate functionality to preserve the apparently instant response. PLATO demonstrates the feasibility of petroleum computing applications combining an intuitive graphical interface, high-performance computing of physical models, and real-time output graphics.

  6. Synchronicity, instant messaging, and performance among financial traders

    PubMed Central

    Saavedra, Serguei; Hagerty, Kathleen; Uzzi, Brian

    2011-01-01

    Successful animal systems often manage risk through synchronous behavior that spontaneously arises without leadership. In critical human systems facing risk, such as financial markets or military operations, our understanding of the benefits associated with synchronicity is nascent but promising. Building on previous work illuminating commonalities between ecological and human systems, we compare the activity patterns of individual financial traders with the simultaneous activity of other traders—an individual and spontaneous characteristic we call synchronous trading. Additionally, we examine the association of synchronous trading with individual performance and communication patterns. Analyzing empirical data on day traders’ second-to-second trading and instant messaging, we find that the higher the traders’ synchronous trading is, the less likely they are to lose money at the end of the day. We also find that the daily instant messaging patterns of traders are closely associated with their level of synchronous trading. This result suggests that synchronicity and vanguard technology may help traders cope with risky decisions in complex systems and may furnish unique prospects for achieving collective and individual goals. PMID:21402941

  7. Synchronicity, instant messaging, and performance among financial traders.

    PubMed

    Saavedra, Serguei; Hagerty, Kathleen; Uzzi, Brian

    2011-03-29

    Successful animal systems often manage risk through synchronous behavior that spontaneously arises without leadership. In critical human systems facing risk, such as financial markets or military operations, our understanding of the benefits associated with synchronicity is nascent but promising. Building on previous work illuminating commonalities between ecological and human systems, we compare the activity patterns of individual financial traders with the simultaneous activity of other traders--an individual and spontaneous characteristic we call synchronous trading. Additionally, we examine the association of synchronous trading with individual performance and communication patterns. Analyzing empirical data on day traders' second-to-second trading and instant messaging, we find that the higher the traders' synchronous trading is, the less likely they are to lose money at the end of the day. We also find that the daily instant messaging patterns of traders are closely associated with their level of synchronous trading. This result suggests that synchronicity and vanguard technology may help traders cope with risky decisions in complex systems and may furnish unique prospects for achieving collective and individual goals.

  8. InstantLabs®? Salmonella species food safety kit.

    PubMed

    Sharma, Neil; Bambusch, Lauren; Le, Thu; Hayman, Melinda; Montez, Sergio J

    2014-01-01

    The InstantLabs® Salmonella Species Food Safety Kit was validated against the International Organization for Standardization (ISO) reference method* 6579:2002 for the detection of Salmonella species. The matrixes (unprocessed rolled oats, wheat flour, and oat flour) were inoculated with 1 CFU/test portion of Salmonella to generate fractional positives (5-15) in 20 inoculated samples. The inatrixes were co-inoculated with Escherichia coli O157:H7 at 2-5 times the level of Salmonella to demonstrate the potential for using the same enrichment culture in the future to detect of multiple organisms. Samples were validated using 750 g test portion enriched in FASTGRO SE at 42 ± 1°C for 16-20 h. All samples were confirmed using the ISO reference method, regardless of initial screen result. The InstantLabs test method performed as well as or better than the reference method for the detection of Salmonella species in unprocessed rolled oats, wheat flour, and oat flour. Inclusivity and exclusivity testing revealed no false negatives and no false positives among the 100 Salmonella serovars and 30 non-Salmonella species examined. Finally, the method was shown to be robust when variations to enrichment time, DNA extract hold time, and DNA volume were varied (data not shown).

  9. [Elaboration of instant corn flour by hydrothermal process I].

    PubMed

    Martínez B, F; el-Dahs, A A

    1993-12-01

    The objective of this research was to investigate a simplified hydrothermal process for the production of instant corn flour and evaluate some variables that affected the degree of gelatinization of corn flour, and evaluate some technological characteristics of the flour. The use of grits of lesser particle diameter and increasing temperature of the soaking water resulted in an increase in the rate of absorption of water of grits, permitting a reduction of soaking time necessary for the process. The instant corn flour prepared by the hydrothermal process using corn grits soaked in water at room temperature (28-30 degrees C) for 5 hours and steaming for 1 minute at 118 degrees C presented characteristics of viscosity, water absorption index and water solubility index similar to that of flours prepared with grits soaked in water at a temperature higher tan room temperature and different steaming time (5 and 15 minutes). The characteristics of color and shelf life of corn flour were improved with the hydrothermal process.

  10. Studies on the optimization and stability of instant wheat porridge (Dalia) mix.

    PubMed

    Ayub Khan, Mohammed; Dutt Semwal, Anil; Kumar Sharma, Gopal; Singh Bawa, Amarinder

    2014-06-01

    Instant wheat porridge (Dalia) mix based on precooked broken wheat, sugar, skim milk powder and flavouring agents was developed using response surface methodology and central composite rotatable design. Stability of instant wheat porridge (Dalia) mix packed in polypropylene (PP) and metallised polyester (MP) pouches was evaluated. Instant porridge (Dalia) mix remained stable for 9 and 12 m respectively in PP and MP pouches under ambient temperature (15-34 °C) conditions. Deterioration in instant porridge mix during storage was mainly caused by autoxidation of lipids, browning due to maillard reaction and development of off-flavour.

  11. Stereoscopic adapter based system using HMD and image processing software for supporting inner ear operations performed using operating microscope

    NASA Astrophysics Data System (ADS)

    Leśniewski, Marcin; Kujawińska, Malgorzata; Kucharski, Tomasz; Niemczyk, Kazimierz

    2006-02-01

    Recently surgery requires extensive support from imaging technologies in order to increase effectiveness and safety of operations. One of important tasks is to enhance visualisation of quasi-phase (transparent) 3D structures. In this paper authors present a few of practical hardware solutions using of operational stereoscopic microscope with two image acquisition channels, stereoscopic adapter and Helmet Mounted Display (HMD) for stereoscopic visualization of operational field "in real time". Special attention is paid to the development of opto- mechanical unit. The authors focus on searching cheap, accurate and ergonomic solutions. A few proposals are analyzed: typical stereoscopic adapter with two image acquisition channels equipped with developed software for image low contrast enhancement for stereoscopic observation in stereoscopic HMD of operational field, visual - picture adapter (real operational view through microscope channels or processed operational field images observation in "real time").

  12. A proposed super-fast scheme for instant-detect-instant-kill of a ground-to-air missile

    NASA Astrophysics Data System (ADS)

    Hu, Chialun J.

    2013-01-01

    When we apply the newly developed LPED (local polar edge detection) image processing method to a binary IR-image which contains a special meteorite-like streak produced by the enemy SAM, the image processing speed can be even enhanced further if another novel preprocessing scheme is used. This novel preprocessing scheme is achieved by taking the advantage of the characteristic geometry of the meteorite-like target into consideration. That is, we only take the clustered high temperature image points making the shape of a slender cylinder ended with a broom-like exhaust fume into consideration. Then we can spatial-filter or pre-extract the cylinder by its geometrical property before we apply the LPED method. This will then result in a super-fast detection, super-fast tracking and super-fast targeting on the CM (center of mass) point of the cylinder. This CM point is just the "heart" of the flying missile. Incorporating this targeting system with a high power laser gun through the use of a Wollaston prism, an air-borne instant detect-instant-kill SAM killer system may then be constructed.

  13. User experience while viewing stereoscopic 3D television

    PubMed Central

    Read, Jenny C.A.; Bohr, Iwo

    2014-01-01

    3D display technologies have been linked to visual discomfort and fatigue. In a lab-based study with a between-subjects design, 433 viewers aged from 4 to 82 years watched the same movie in either 2D or stereo 3D (S3D), and subjectively reported on a range of aspects of their viewing experience. Our results suggest that a minority of viewers, around 14%, experience adverse effects due to viewing S3D, mainly headache and eyestrain. A control experiment where participants viewed 2D content through 3D glasses suggests that around 8% may report adverse effects which are not due directly to viewing S3D, but instead are due to the glasses or to negative preconceptions about S3D (the ‘nocebo effect'). Women were slightly more likely than men to report adverse effects with S3D. We could not detect any link between pre-existing eye conditions or low stereoacuity and the likelihood of experiencing adverse effects with S3D. Practitioner Summary: Stereoscopic 3D (S3D) has been linked to visual discomfort and fatigue. Viewers watched the same movie in either 2D or stereo 3D (between-subjects design). Around 14% reported effects such as headache and eyestrain linked to S3D itself, while 8% report adverse effects attributable to 3D glasses or negative expectations. PMID:24874550

  14. User benefits of visualization with 3-D stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Wichansky, Anna M.

    1991-08-01

    The power of today''s supercomputers promises tremendous benefits to users in terms of productivity, creativity, and excitement in computing. A study of a stereoscopic display system for computer workstations was conducted with 20 users and third-party software developers, to determine whether 3-D stereo displays were perceived as better than flat, 2- 1/2D displays. Users perceived more benefits of 3-D stereo in applications such as molecular modeling and cell biology, which involved viewing of complex, abstract, amorphous objects. Users typically mentioned clearer visualization and better understanding of data, easier recognition of form and pattern, and more fun and excitement at work as the chief benefits of stereo displays. Human factors issues affecting the usefulness of stereo included use of 3-D glasses over regular eyeglasses, difficulties in group viewing, lack of portability, and need for better input devices. The future marketability of 3-D stereo displays would be improved by eliminating the need for users to wear equipment, reducing cost, and identifying markets where the abstract display value can be maximized.

  15. Stereoscopic camera system for live-action and sports productions

    NASA Astrophysics Data System (ADS)

    Adkins, Craig

    1997-05-01

    By all accounts I am a cowboy cameraman. I began my career as a ski bum in the Swiss Alps at the age of 18. Once I had picked up a Super 8 camera and filmed my first skiing sequence, the mold was pretty much set. I have concentrated my direction on shooting live action in extreme environments ever since. I shun the use of tripods and my experience in artificial lighting is minimal. My technical knowledge of the equipment and medium I use is limited to practical use dictated by weather and terrain conditions. When confronted with a frozen film gate in a raging blizzard, perched atop a 200 foot drop, there are only so many options. This brief personal history prefaces the underlying theme of the camera system I designed and have been using in the field for the past year. I do not claim to be a deep well of information on stereoscopic theory and technology nor a maverick inventor. Rather, I am someone who saw stereo video and realized it was a significant improvement in existing visual technology. The resulting experience I have gained from building a stereo video camera system is purely empirical, helped by other's shared insights and my own trial and error.

  16. A comparison of some predictors of stereoscopic match correctness

    NASA Astrophysics Data System (ADS)

    Petran, Val; Merat, Frank

    2012-05-01

    Previously we introduced the concept of continuous quantification of uniqueness, as a general purpose technique designed to be applicable to any situation in which there is a need to decide which of several equally effective objects to choose for a task, that requires recognition of the chosen object, in a variety of contexts, by comparing attributes which contain a non trivial amount of context dependent variability. We defined that uniqueness assessment as an algorithm that computes a fuzzy set membership function that measures some but not all aspects of the probability that the sought after object will not be confused with other objects in the space being searched. We evaluated the usefulness of that concept by experimentally assessing the extent to which the uniqueness of the SAD global minimum of locally computed image subset dissimilarity was both a predictor of bidirectional match compliance with the Epipolar Constraint, and a predictor of bidirectional match disparity correctness, for the classical stereoscopic correspondence problem of computer vision, and in that context found the uniqueness of the aforementioned global minimum to be a useful but imperfect predictor of success. In this paper we compare the usefulness of the uniqueness of the aforementioned global minimum to that of, the magnitude of that same global minimum, the magnitude of variability across contributors to that global minimum, uniqueness of that variability, and co-occurrence of the global minimum of local image subset dissimilarity and global minimum of variability across contributors to local image subset dissimilarity.

  17. Stereoscopic 3D display with color interlacing improves perceived depth

    PubMed Central

    Kim, Joohwan; Johnson, Paul V.; Banks, Martin S.

    2014-01-01

    Temporal interlacing is a method for presenting stereoscopic 3D content whereby the two eyes’ views are presented at different times and optical filtering selectively delivers the appropriate view to each eye. This approach is prone to distortions in perceived depth because the visual system can interpret the temporal delay between binocular views as spatial disparity. We propose a novel color-interlacing display protocol that reverses the order of binocular presentation for the green primary but maintains the order for the red and blue primaries: During the first sub-frame, the left eye sees the green component of the left-eye view and the right eye sees the red and blue components of the right-eye view, and vice versa during the second sub-frame. The proposed method distributes the luminance of each eye’s view more evenly over time. Because disparity estimation is based primarily on luminance information, a more even distribution of luminance over time should reduce depth distortion. We conducted a psychophysical experiment to test these expectations and indeed found that less depth distortion occurs with color interlacing than temporal interlacing. PMID:25607161

  18. Stereoscopic Vision in the Absence of the Lateral Occipital Cortex

    PubMed Central

    Read, Jenny C. A.; Phillipson, Graeme P.; Serrano-Pedraza, Ignacio; Milner, A. David; Parker, Andrew J.

    2010-01-01

    Both dorsal and ventral cortical visual streams contain neurons sensitive to binocular disparities, but the two streams may underlie different aspects of stereoscopic vision. Here we investigate stereopsis in the neurological patient D.F., whose ventral stream, specifically lateral occipital cortex, has been damaged bilaterally, causing profound visual form agnosia. Despite her severe damage to cortical visual areas, we report that DF's stereo vision is strikingly unimpaired. She is better than many control observers at using binocular disparity to judge whether an isolated object appears near or far, and to resolve ambiguous structure-from-motion. DF is, however, poor at using relative disparity between features at different locations across the visual field. This may stem from a difficulty in identifying the surface boundaries where relative disparity is available. We suggest that the ventral processing stream may play a critical role in enabling healthy observers to extract fine depth information from relative disparities within one surface or between surfaces located in different parts of the visual field. PMID:20830303

  19. Measurements of turbulent premixed flame dynamics using cinema stereoscopic PIV

    NASA Astrophysics Data System (ADS)

    Steinberg, Adam M.; Driscoll, James F.; Ceccio, Steven L.

    2008-06-01

    A new experimental method is described that provides high-speed movies of turbulent premixed flame wrinkling dynamics and the associated vorticity fields. This method employs cinema stereoscopic particle image velocimetry and has been applied to a turbulent slot Bunsen flame. Three-component velocity fields were measured with high temporal and spatial resolutions of 0.9 ms and 140 μm, respectively. The flame-front location was determined using a new multi-step method based on particle image gradients, which is described. Comparisons are made between flame fronts found with this method and simultaneous CH-PLIF images. These show that the flame contour determined corresponds well to the true location of maximum gas density gradient. Time histories of typical eddy-flame interactions are reported and several important phenomena identified. Outwardly rotating eddy pairs wrinkle the flame and are attenuated at they pass through the flamelet. Significant flame-generated vorticity is produced downstream of the wrinkled tip. Similar wrinkles are caused by larger groups of outwardly rotating eddies. Inwardly rotating pairs cause significant convex wrinkles that grow as the flame propagates. These wrinkles encounter other eddies that alter their behavior. The effects of the hydrodynamic and diffusive instabilities are observed and found to be significant contributors to the formation and propagation of wrinkles.

  20. Telescope Array UHECR composition measurement via stereoscopic fluorescence observation

    NASA Astrophysics Data System (ADS)

    Stroman, Thomas; Bergman, Douglas; Telescope Array Collaboration

    2016-03-01

    When entering Earth's atmosphere at ultra-high energies, cosmic rays (UHECRs) produce extensive air showers whose longitudinal development is influenced by the incident primary particle's mass. Each longitudinal shower profile reaches its maximum particle count at an atmospheric slant depth Xmax, and the distributions of observed Xmax values can be compared to those predicted by detailed simulations of the air-shower physics and the detector; accurately simulated compositions that most closely resemble that found in nature will produce the best agreement between predicted and observed Xmax distributions. This is the basis of composition measurement at the Telescope Array experiment, the largest and most sensitive UHECR detector in the northern hemisphere. At the perimeter of a large surface-detector array are three fluorescence telescope stations, whose overlapping apertures enable high-precision reconstruction of Xmax from stereoscopic observation of air-shower longitudinal profiles. We present the distribution of Xmax observed during eight years of operation, and from comparisons with several simulated combinations of composition and high-energy hadronic physics, we show that a low primary mass is favored at E >10 18 . 2 eV.

  1. Re-engineering the stereoscope for the 21st Century

    NASA Astrophysics Data System (ADS)

    Kollin, Joel S.; Hollander, Ari J.

    2007-02-01

    While discussing the current state of stereo head-mounted and 3D projection displays, the authors came to the realization that flat-panel LCD displays offer higher resolution than projection for stereo display at a low (and continually dropping) cost. More specifically, where head-mounted displays of moderate resolution and field-of-view cost tens of thousands of dollars, we can achieve an angular resolution approaching that of the human eye with a field-of-view (FOV) greater than 90° for less than $1500. For many immersive applications head tracking is unnecessary and sometimes even undesirable, and a low cost/high quality wide FOV display may significantly increase the application space for 3D display. After outlining the problem and potential of this solution we describe the initial construction of a simple Wheatstone stereoscope using 24" LCD displays and then show engineering improvements that increase the FOV and usability of the system. The applicability of a high-immersion, high-resolution display for art, entertainment, and simulation is presented along with a content production system that utilizes the capabilities of the system. We then discuss the potential use of the system for VR pain control therapy, treatment of post-traumatic stress disorders and other serious games applications.

  2. Measurement of compressed breast thickness by optical stereoscopic photogrammetry

    SciTech Connect

    Tyson, Albert H.; Mawdsley, Gordon E.; Yaffe, Martin J.

    2009-02-15

    The determination of volumetric breast density (VBD) from mammograms requires accurate knowledge of the thickness of the compressed breast. In attempting to accurately determine VBD from images obtained on conventional mammography systems, the authors found that the thickness reported by a number of mammography systems in the field varied by as much as 15 mm when compressing the same breast or phantom. In order to evaluate the behavior of mammographic compression systems and to be able to predict the thickness at different locations in the breast on patients, they have developed a method for measuring the local thickness of the breast at all points of contact with the compression paddle using optical stereoscopic photogrammetry. On both flat (solid) and compressible phantoms, the measurements were accurate to better than 1 mm with a precision of 0.2 mm. In a pilot study, this method was used to measure thickness on 108 volunteers who were undergoing mammography examination. This measurement tool will allow us to characterize paddle surface deformations, deflections and calibration offsets for mammographic units.

  3. Stereoscopic 3D display with color interlacing improves perceived depth.

    PubMed

    Kim, Joohwan; Johnson, Paul V; Banks, Martin S

    2014-12-29

    Temporal interlacing is a method for presenting stereoscopic 3D content whereby the two eyes' views are presented at different times and optical filtering selectively delivers the appropriate view to each eye. This approach is prone to distortions in perceived depth because the visual system can interpret the temporal delay between binocular views as spatial disparity. We propose a novel color-interlacing display protocol that reverses the order of binocular presentation for the green primary but maintains the order for the red and blue primaries: During the first sub-frame, the left eye sees the green component of the left-eye view and the right eye sees the red and blue components of the right-eye view, and vice versa during the second sub-frame. The proposed method distributes the luminance of each eye's view more evenly over time. Because disparity estimation is based primarily on luminance information, a more even distribution of luminance over time should reduce depth distortion. We conducted a psychophysical experiment to test these expectations and indeed found that less depth distortion occurs with color interlacing than temporal interlacing.

  4. Stereoscopic perception of real depths at large distances.

    PubMed

    Palmisano, Stephen; Gillam, Barbara; Govan, Donovan G; Allison, Robert S; Harris, Julie M

    2010-06-01

    There has been no direct examination of stereoscopic depth perception at very large observation distances and depths. We measured perceptions of depth magnitude at distances where it is frequently reported without evidence that stereopsis is non-functional. We adapted methods pioneered at distances up to 9 m by R. S. Allison, B. J. Gillam, and E. Vecellio (2009) for use in a 381-m-long railway tunnel. Pairs of Light Emitting Diode (LED) targets were presented either in complete darkness or with the environment lit as far as the nearest LED (the observation distance). We found that binocular, but not monocular, estimates of the depth between pairs of LEDs increased with their physical depths up to the maximum depth separation tested (248 m). Binocular estimates of depth were much larger with a lit foreground than in darkness and increased as the observation distance increased from 20 to 40 m, indicating that binocular disparity can be scaled for much larger distances than previously realized. Since these observation distances were well beyond the range of vertical disparity and oculomotor cues, this scaling must rely on perspective cues. We also ran control experiments at smaller distances, which showed that estimates of depth and distance correlate poorly and that our metric estimation method gives similar results to a comparison method under the same conditions.

  5. Digital stereoscopic photography using StereoData Maker

    NASA Astrophysics Data System (ADS)

    Toeppen, John; Sykes, David

    2009-02-01

    Stereoscopic digital photography has become much more practical with the use of USB wired connections between a pair of Canon cameras using StereoData Maker software for precise synchronization. StereoPhoto Maker software is now used to automatically combine and align right and left image files to produce a stereo pair. Side by side images are saved as pairs and may be viewed using software that converts the images into the preferred viewing format at the time of display. Stereo images may be shared on the internet, displayed on computer monitors, autostereo displays, viewed on high definition 3D TVs, or projected for a group. Stereo photographers are now free to control composition using point and shoot settings, or are able to control shutter speed, aperture, focus, ISO, and zoom. The quality of the output depends on the developed skills of the photographer as well as their understanding of the software, human vision and the geometry they choose for their cameras and subjects. Observers of digital stereo images can zoom in for greater detail and scroll across large panoramic fields with a few keystrokes. The art, science, and methods of taking, creating and viewing digital stereo photos are presented in a historic and developmental context in this paper.

  6. Toward a stereoscopic encoder/decoder for digital cinema

    NASA Astrophysics Data System (ADS)

    Bensalma, Rafik; Larabi, Mohamed-Chaker

    2008-02-01

    The digital cinema is very challenging because it represents tomorrow way of capturing, post-producing and projecting movies. Specifications on this media are provided by DCI (Digital Cinema Initiatives) founded by the Hollywood Majors. Among the specifications we can find issues about resolution, bitrate, JPEG2000 compression Moreover, the market assumes that 3D could raise the turnover of cinema industry. The problem with is the availability of 2 streams (left and right) that double the amount of data and need adapted devices to decode and project movies. Cinema industry, represented by the stereoscopic group in SMPTE has expressed the need of having a unique master that combines two streams in one. This paper focuses on the study of the generation of a master with one of the streams and the embedment of the redundant information as metadata in JPEG2000 code-stream or MXF. The idea is to use the reference image in addition to some metadata to reconstruct the target image. The metadata represent the residual image and the contours description. Quality of reconstructed images depends on the compression ratio of the residual image. The obtained results are encouraging and the choice between JPEG2000 metadata embedding and MXF metadata still to be done.

  7. Stereoscopic, thermal, and true deep cumulus cloud top heights

    NASA Astrophysics Data System (ADS)

    Llewellyn-Jones, D. T.; Corlett, G. K.; Lawrence, S. P.; Remedios, J. J.; Sherwood, S. C.; Chae, J.; Minnis, P.; McGill, M.

    2004-05-01

    We compare cloud-top height estimates from several sensors: thermal tops from GOES-8 and MODIS, stereoscopic tops from MISR, and directly measured heights from the Goddard Cloud Physics Lidar on board the ER-2, all collected during the CRYSTAL-FACE field campaign. Comparisons reveal a persistent 1-2 km underestimation of cloud-top heights by thermal imagery, even when the finite optical extinctions near cloud top and in thin overlying cirrus are taken into account. The most severe underestimates occur for the tallest clouds. The MISR "best-sinds" and lidar estimates disagree in very similar ways with thermally estimated tops, which we take as evidence of excellent performance by MISR. Encouraged by this, we use MISR to examine variations in cloud penetration and thermal top height errors in several locations of tropical deep convection over multiple seasons. The goals of this are, first, to learn how cloud penetration depends on the near-tropopause environment; and second, to gain further insight into the mysterious underestimation of tops by thermal imagery.

  8. Measurement of compressed breast thickness by optical stereoscopic photogrammetry.

    PubMed

    Tyson, Albert H; Mawdsley, Gordon E; Yaffe, Martin J

    2009-02-01

    The determination of volumetric breast density (VBD) from mammograms requires accurate knowledge of the thickness of the compressed breast. In attempting to accurately determine VBD from images obtained on conventional mammography systems, the authors found that the thickness reported by a number of mammography systems in the field varied by as much as 15 mm when compressing the same breast or phantom. In order to evaluate the behavior of mammographic compression systems and to be able to predict the thickness at different locations in the breast on patients, they have developed a method for measuring the local thickness of the breast at all points of contact with the compression paddle using optical stereoscopic photogrammetry. On both flat (solid) and compressible phantoms, the measurements were accurate to better than 1 mm with a precision of 0.2 mm. In a pilot study, this method was used to measure thickness on 108 volunteers who were undergoing mammography examination. This measurement tool will allow us to characterize paddle surface deformations, deflections and calibration offsets for mammographic units.

  9. Temporal channels and disparity representations in stereoscopic depth perception.

    PubMed

    Doi, Takahiro; Takano, Maki; Fujita, Ichiro

    2013-11-26

    Stereoscopic depth perception is supported by a combination of correlation-based and match-based representations of binocular disparity. It also relies on both transient and sustained temporal channels of the visual system. Previous studies suggest that the relative contribution of the correlation-based representation (over the match-based representation) and the transient channel (over the sustained channel) to depth perception increases with the disparity magnitude. The mechanisms of the correlation-based and match-based representations may receive preferential inputs from the transient and sustained channels, respectively. We examined near/far discrimination by observers using random-dot stereograms refreshed at various rates. The relative contribution of the two representations was inferred by changing the fraction of dots that were contrast reversed between the two eyes. Both representations contributed to depth discrimination over the tested range of refresh rates. As the rate increased, the correlation-based representation increased its contribution to near/far discrimination. Another experiment revealed that the match-based representation was constructed by exploiting the variability in correlation-based disparity signals. Thus, the relative weight of the transient over sustained channel differs between the two representations. The correlation-based representation dominates depth perception with dynamic inputs. The match-based representation, which may be a nonlinear refinement of the correlation-based representation, exerts more influence on depth perception with slower inputs.

  10. Reheating the D-brane universe via instant preheating

    SciTech Connect

    Panda, Sudhakar; Sami, M.; Thongkool, I.

    2010-05-15

    We investigate a possibility of reheating in a scenario of D-brane inflation in a warped deformed conifold background which includes perturbative corrections to throat geometry sourced by a chiral operator of dimension 3/2 in the conformal field theory. The effective D-brane potential, in this case, belongs to the class of nonoscillatory models of inflation for which the conventional reheating mechanism does not work. We find that gravitational particle production is inefficient and leads to reheating temperature of the order of 10{sup 8} GeV. We show that instant preheating is quite suitable to the present scenario and can easily reheat the universe to a temperature which is higher by about 3 orders of magnitude than its counterpart associated with gravitational particle production. The reheating temperature is shown to be insensitive to a particular choice of inflationary parameters suitable to observations.

  11. Determination of the acid value of instant noodles: interlaboratory study.

    PubMed

    Hakoda, Akiko; Sakaida, Kenichi; Suzuki, Tadanao; Yasui, Akemi

    2006-01-01

    An interlaboratory study was performed to evaluate the method for determining the acid value of instant noodles, based on the Japanese Agricultural Standard (JAS), with extraction of lipid using petroleum ether at a volume of 100 mL to the test portion of 25 g. Thirteen laboratories participated and analyzed 5 test samples as blind duplicates. Statistical treatment revealed that the repeatability (RSDr) of acid value was <6.5%, and the reproducibility (RSDR) of acid value was <9.6%. The HorRat values (RSDR/predicted RSDR) were 1.2-1.8, where the RSDR and the predicted RSDR were obtained in terms of free fatty acids in the noodles per unit weight, using the equation [acid value = percent free fatty acids (as oleic) x 1.99] and the extracted lipid contents. This method was shown to have acceptable precision by the present study.

  12. En route to an "instant family": psychosocial considerations.

    PubMed

    Baor, Liora; Blickstein, Isaac

    2005-03-01

    Societal and cultural norms require that a worthwhile person engage in reproduction and formation of a family. Young adults who postpone childbearing may presume that fertility is granted. When all other measures fail, the use of assisted reproductive technologies is considered the ultimate salvation for these couples. It is highly stressful and may lead to significant negative psychological consequences (loss of self-esteem, confidence, health, close relationships, security, and hope). Assisted reproductive technology may produce multiple pregnancy, which is frequently overlooked or underappreciated by infertile couples. Despite the real risks associated with a multiple pregnancy and birth, infertile patients often express a desperate wish to have twins or triplets, thereby accomplishing an instant family. It is necessary to provide these couples with detailed information on the risks of multiple pregnancy and birth.

  13. Asthma and rhinitis due to ethylcyanoacrylate instant glue.

    PubMed

    Kopp, S K; McKay, R T; Moller, D R; Cassedy, K; Brooks, S M

    1985-05-01

    A 32-year-old man developed asthma due to a cyanoacrylate ester instant glue used in building remote control model airplanes. Typical asthma and rhinitis symptoms developed after 1 year using the adhesive. Delayed onset of symptoms was consistently related to the application of the glue to balsa wood. Bronchial provocation to the glue vapors in a manner simulating his home exposure resulted in a late asthmatic response with rhinorrhea and lacrimation. Increased bronchial hyperreactivity to methacholine occurred after bronchial challenge and persisted for several weeks. Complete resolution of the patient's asthma symptoms occurred with avoidance of the glue. Reversion to a negative methacholine challenge test occurred after 6 months of continued avoidance.

  14. Effects of Instant Messaging on School Performance in Adolescents.

    PubMed

    Grover, Karan; Pecor, Keith; Malkowski, Michael; Kang, Lilia; Machado, Sasha; Lulla, Roshni; Heisey, David; Ming, Xue

    2016-06-01

    Instant messaging may compromise sleep quality and school performance in adolescents. We aimed to determine associations between nighttime messaging and daytime sleepiness, self-reported sleep parameters, and/or school performance. Students from 3 high schools in New Jersey completed anonymous questionnaires assessing sleep duration, daytime sleepiness, messaging habits, and academic performance. Of the 2,352 students sampled, 1,537 responses were contrasted among grades, sexes, and messaging duration, both before and after lights out. Students who reported longer duration of messaging after lights out were more likely to report a shorter sleep duration, higher rate of daytime sleepiness, and poorer academic performance. Messaging before lights out was not associated with higher rates of daytime sleepiness or poorer academic performance. Females reported more messaging, more daytime sleepiness, and better academic performance than males. There may be an association between text messaging and school performance in this cohort of students.

  15. Instant tooth whitening from a silica toothpaste containing blue covarine.

    PubMed

    Collins, Luisa Z; Naeeni, Mojgan; Platten, Suzanne M

    2008-01-01

    To measure the instant whitening effect delivered immediately after brushing with a novel silica whitening toothpaste containing blue covarine. A controlled, single blind, cross-over study was performed to compare the tooth colour measured in a group of subjects at baseline and immediately after brushing with a silica whitening toothpaste containing blue covarine versus a clear gel negative control toothpaste. Measurements of tooth colour were made using a mobile non-contact camera-based digital imaging system and expressed as CIELAB and WIO whiteness index. Analysis of covariance (ANCOVA) showed that the silica whitening toothpaste containing blue covarine was significantly more effective than the negative control toothpaste (p < 0.05), and made teeth measurably less yellow, less red and overall whiter immediately after brushing. A statistically significant reduction in tooth yellowness and improvement in tooth whiteness was measured immediately after brushing with a novel whitening toothpaste containing blue covarine.

  16. Factors Affecting Use of Instant Messaging Software by Information Technology Professionals

    ERIC Educational Resources Information Center

    Pratt, Robert C.

    2010-01-01

    Instant messaging systems--a type of social networking technology that connects people who are physically separated but working together--have seen a dramatic rise in use in globally dispersed organizations, yet there is an absence of academic research in predictive factors of instant messaging adoption. This study examined the factors influencing…

  17. Characterization of yellow rice and development of instant flours by hydrothermal process.

    PubMed

    Martínez-Bustos, F; Delgado, L L; Victorio, M G; Morales, S E

    1997-03-01

    Commercial brown and yellow milled rice submitted to inappropriate storage conditions were characterized and utilized to develop instant flours that were used in the preparation of atoles. The grains were classified as long-thin; the average size was 2.13 x 6.79 mm. The milling yields obtained in laboratory with paddy rice were 70% brown rice and 60% milled rice. Brown rice and yellow milled rice had similar amylose contents, 22.5 and 25.6% respectively. Gel consistency was soft with low gelatinization temperature (63-68 degrees C) for both samples. Field fungi, such as Helminthosporium oryzae, and storage fungi, such as Aspergillus spp, were present in paddy, yellow milled and commercial rice. The fungus Helminthosporium oryzae, Aspergillus spp, and Penicillum spp were not present in instant flours. Instant flours were prepared by soaking the grain in water, and then steaming, drying and milling it. The highest values for water absorption index were obtained from yellow milled instant rice flour. The color of yellow milled instant rice flour varied from white ("L") to pale yellow (lesser values of "b"). The lower viscosity of the instant flours indicates the breakdown of polymers and reveals that unintact starch granules were not present in instant flours. Protein and ash contents of brown and milled rice were unaffected by hydrothermal process, and the lipid content showed only little changes. Sensory analyses carried out on the atoles prepared with instant flours considered them acceptable, specially for products made from milled yellow rice.

  18. Influence of the startup instant of quench in a superconducting current limiter

    SciTech Connect

    Leveque, J.; Netter, D.; Rezzoug, A.; Caron, J.P.; Sargos, F.M.

    1996-09-01

    The influence of the startup instant of the quench in a superconducting current limiter is studied. The heat transfer equation is numerically solved, using finite difference method, and taking the effects of current sharing into account. The results show the importance of this instant on the dissipated power, the temperature-increase and on the efficiency of the current limitation.

  19. We Learn What We Do: Developing a Repertoire of Writing Practices in an Instant Messaging World

    ERIC Educational Resources Information Center

    Jacobs, Gloria E.

    2008-01-01

    A case study of an adolescent girl provides a framework to understand what factors contribute to the development of a strong writer within an instant messaging world. The study shows instant messaging is one of a larger repertoire of practices. Facility in school-based writing was developed through a school culture that supported writing in the…

  20. Instant Messaging between Students and Faculty: A Tool for Increasing Student-Faculty Interaction

    ERIC Educational Resources Information Center

    Hickerson, Corey A.; Giglio, Matt

    2009-01-01

    This study explores the pedagogical potential of instant messaging in a communication course. Two instructors made themselves available to students via instant messaging as a supplement to other modes of communication (e.g., e-mail, office hours). In order to gauge students' reactions to and use of the technology, the researchers kept logs of…

  1. Using Instant Feedback System and Micro Exams to Enhance Active Learning

    ERIC Educational Resources Information Center

    Sabag, N.; Kosolapov, S.

    2012-01-01

    This paper presents the outcomes of the preliminary survey in which the method of IFS was used to integrate motivating questions into the lecture presentations in order to increase the students' involvement. Instant Feedback System (IFS) enables the educators to improve their own teaching by getting instant and real-time feedback about how clear…

  2. Using an Instant Messenger to Learn a Foreign Language in a Peer-Tutoring Environment

    ERIC Educational Resources Information Center

    Baek, Joeun; Yoo, Yungtai; Lee, Kyungsuk; Jung, Bokmoon; Baek, Youngkyun

    2017-01-01

    This study explores useful ways of using an instant messenger in a peer-tutoring environment when two students exchange their mother languages. Seven learners of Korean and seven Korean students learning English were paired randomly to conduct language exchange via an instant messenger, KakaoTalk. The pairs (five of male and female pair and two of…

  3. Fast Times and Digital Literacy: Participation Roles and Portfolio Construction within Instant Messaging

    ERIC Educational Resources Information Center

    Jacobs, Gloria E.

    2006-01-01

    The purpose of this study was to develop an understanding of adolescent use of instant messaging. Grounded in the New Literacy Studies stance that literacy is a social practice embedded in local contexts and informed by global ideologies (Street, 1995), I argue that participation in digital literacies such as instant messaging has implications for…

  4. Instant transformation of learned repulsion into motivational ‘wanting’

    PubMed Central

    Robinson, Mike J.F.; Berridge, Kent C.

    2013-01-01

    Summary Background Learned cues for pleasant rewards often elicit desire, which in addicts may become compulsive. According to the dominant view in addiction neuroscience and reinforcement modeling, such desires are the simple products of learning, coming from past association with reward outcome. Results We demonstrate that cravings are more than merely the product of accumulated pleasure memories: even a repulsive learned cue for unpleasantness can become suddenly desired via activation of mesocorticolimbic circuitry. Rats learned repulsion toward a Pavlovian cue (briefly-inserted metal lever) that always predicted an unpleasant Dead Sea saltiness sensation. Yet upon first re-encounter in a novel sodium depletion state to promote mesocorticolimbic reactivity (reflected by elevated Fos activation in ventral tegmentum, nucleus accumbens, ventral pallidum, and orbitofrontal prefrontal cortex), the learned cue was instantly transformed into an attractive and powerful motivational magnet. Rats jumped and gnawed on the suddenly attractive Pavlovian lever cue, despite having never yet tasted intense saltiness itself as anything other than disgusting. Conclusions Instant desire transformation of a learned cue contradicts views that Pavlovian desires are based essentially on previously learned values (e.g., prediction error or temporal difference models). Instead desire is re-computed at re-encounter by integrating Pavlovian information with current brain/physiological state. This powerful brain transformation reversed strong learned revulsion into avid attraction. Applied to addiction, related mesocorticolimbic transformations (e.g., drugs, neural sensitization) of cues for already pleasant drug experiences could create even more intense cravings. This cue/state transformation helps define what it means to say that addiction hijacks brain limbic circuits of natural reward. PMID:23375893

  5. Distributed Adaptive Control: Beyond Single-Instant, Discrete Variables

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Bieniawski, Stefan

    2005-01-01

    In extensive form noncooperative game theory, at each instant t, each agent i sets its state x, independently of the other agents, by sampling an associated distribution, q(sub i)(x(sub i)). The coupling between the agents arises in the joint evolution of those distributions. Distributed control problems can be cast the same way. In those problems the system designer sets aspects of the joint evolution of the distributions to try to optimize the goal for the overall system. Now information theory tells us what the separate q(sub i) of the agents are most likely to be if the system were to have a particular expected value of the objective function G(x(sub 1),x(sub 2), ...). So one can view the job of the system designer as speeding an iterative process. Each step of that process starts with a specified value of E(G), and the convergence of the q(sub i) to the most likely set of distributions consistent with that value. After this the target value for E(sub q)(G) is lowered, and then the process repeats. Previous work has elaborated many schemes for implementing this process when the underlying variables x(sub i) all have a finite number of possible values and G does not extend to multiple instants in time. That work also is based on a fixed mapping from agents to control devices, so that the the statistical independence of the agents' moves means independence of the device states. This paper also extends that work to relax all of these restrictions. This extends the applicability of that work to include continuous spaces and Reinforcement Learning. This paper also elaborates how some of that earlier work can be viewed as a first-principles justification of evolution-based search algorithms.

  6. Instant polysaccharide-based emulsions: impact of microstructure on lipolysis.

    PubMed

    Torcello-Gómez, Amelia; Foster, Timothy J

    2017-06-21

    The development of emulsion-based products through optimisation of ingredients, reduction in energy-input during manufacture, while fulfilling healthy attributes, are major objectives within the food industry. Instant emulsions can meet these features, but comprehensive studies are necessary to investigate the effect of the initial formulation on the final microstructure and, in turn, on the in vitro lipolysis, comprising the double aim of this work. The instant emulsion is formed within 1.5-3 min after pouring the aqueous phase into the oil phase which contains a mixture of emulsifier (Tween 20), swelling particles (Sephadex) and thickeners (hydroxypropylmethylcellulose, HPMC, and guar gum, GG) under mild shearing (180 rpm). The creation of oil-in-water emulsions is monitored in situ by viscosity analysis, the final microstructure visualised by microscopy and the release of free fatty acids under simulated intestinal conditions quantified by titration. Increasing the concentration and molecular weight (Mw) of GG leads to smaller emulsion droplets due to increased bulk viscosity upon shearing. This droplet size reduction is magnified when increasing the Mw of HPMC or swelling capacity of viscosifying particles. In addition, in the absence of the emulsifier Tween 20, the sole use of high-Mw HPMC is effective in emulsification due to combined increased bulk viscosity and interfacial activity. Hence, optimisation of the ingredient choice and usage level is possible when designing microstructures. Finally, emulsions with larger droplet size (>20 μm) display a slower rate and lower extent of lipolysis, while finer emulsions (droplet size ≤20 μm) exhibit maximum rate and extent profiles. This correlates with the extent of emulsion destabilisation observed under intestinal conditions.

  7. Instant magnetic labeling of tumor cells by ultrasound in vitro

    NASA Astrophysics Data System (ADS)

    Mo, Runyang; Yang, Jian; Wu, Ed X.; Lin, Shuyu

    2011-09-01

    Magnetic labeling of living cells creates opportunities for numerous biomedical applications. Here we describe an instantly cell magnetic labeling method based on ultrasound. We present a detailed study on the ultrasound performance of a simple and efficient labeling protocol for H-22 cells in vitro. High frequency focus ultrasound was investigated as an alternative method to achieve instant cell labeling with the magnetic particles without the need for adjunct agents or initiating cell cultures. Mean diameter of 168 nm dextran-T40 coated superparamagnetic iron oxide (SPIO) nanoparticles were prepared by means of classical coprecipitation in solution in our laboratory. H-22 tumor cells suspended in phosphate-buffered saline (PBS, pH=7.2) were exposed to ultrasound at 1.37 MHz for up to 120 s in the presence of SPIOs. The cellular uptake of iron oxide nanoparticles was detected by prussion blue staining. The viability of cells was determined by a trypan blue exclusion test. At 2 W power and 60 s ultrasound exposure in presence of 410 μg/ml SPIOs, H-22 cell labeling efficiency reached 69.4±6.3% and the labeled cells exhibited an iron content of 10.38±2.43 pg per cell. Furthermore, 95.2±3.2% cells remained viable. The results indicated that the ultrasound protocol could be potentially applied to label cells with large-sized magnetic particles. We also calculated the shear stress at the 2 W power and 1.37 MHz used in experiments. The results showed that the shear stress threshold for ultrasonically induced H-22 cell reparable sonoporation was 697 Pa. These findings provide a quantitative guidance in designing ultrasound protocols for cell labeling.

  8. Windows Instant Messaging App Forensics: Facebook and Skype as Case Studies.

    PubMed

    Yang, Teing Yee; Dehghantanha, Ali; Choo, Kim-Kwang Raymond; Muda, Zaiton

    2016-01-01

    Instant messaging (IM) has changed the way people communicate with each other. However, the interactive and instant nature of these applications (apps) made them an attractive choice for malicious cyber activities such as phishing. The forensic examination of IM apps for modern Windows 8.1 (or later) has been largely unexplored, as the platform is relatively new. In this paper, we seek to determine the data remnants from the use of two popular Windows Store application software for instant messaging, namely Facebook and Skype on a Windows 8.1 client machine. This research contributes to an in-depth understanding of the types of terrestrial artefacts that are likely to remain after the use of instant messaging services and application software on a contemporary Windows operating system. Potential artefacts detected during the research include data relating to the installation or uninstallation of the instant messaging application software, log-in and log-off information, contact lists, conversations, and transferred files.

  9. Relationship between threshold and suprathreshold perception of position and stereoscopic depth.

    PubMed

    Patel, Saumil S; Bedell, Harold E; Tsang, Dorcas K; Ukwade, Michael T

    2009-04-01

    We seek to determine the relationship between threshold and suprathreshold perception for position offset and stereoscopic depth perception under conditions that elevate their respective thresholds. Two threshold-elevating conditions were used: (1) increasing the interline gap and (2) dioptric blur. Although increasing the interline gap increases position (Vernier) offset and stereoscopic disparity thresholds substantially, the perception of suprathreshold position offset and stereoscopic depth remains unchanged. Perception of suprathreshold position offset also remains unchanged when the Vernier threshold is elevated by dioptric blur. We show that such normalization of suprathreshold position offset can be attributed to the topographical-map-based encoding of position. On the other hand, dioptric blur increases the stereoscopic disparity thresholds and reduces the perceived suprathreshold stereoscopic depth, which can be accounted for by a disparity-computation model in which the activities of absolute disparity encoders are multiplied by a Gaussian weighting function that is centered on the horopter. Overall, the statement "equal suprathreshold perception occurs in threshold-elevated and unelevated conditions when the stimuli are equally above their corresponding thresholds" describes the results better than the statement "suprathreshold stimuli are perceived as equal when they are equal multiples of their respective threshold values."

  10. A new fast matching method for adaptive compression of stereoscopic images

    NASA Astrophysics Data System (ADS)

    Ortis, A.; Battiato, S.

    2015-03-01

    In the last few years, due to the growing use of stereoscopic images, much effort has been spent by the scientific community to develop algorithms for stereoscopic image compression. Stereo images represent the same scene from two different views, and therefore they typically contain a high degree of redundancy. It is then possible to implement some compression strategies devoted to exploit the intrinsic characteristics of the two involved images that are typically embedded in a MPO (Multi Picture Object) data format. MPO files represents a stereoscopic image by building a list of JPEG images. Our previous work introduced a simple block-matching approach to compute local residual useful to reconstruct during the decoding phase, stereoscopic images that maintain high perceptual quality; this allows to the encoder to force high level of compression at least for one of the two involved images. On the other hand the matching approach, based only on the similarity of the blocks, results rather inefficient. Starting from this point, the main contribution of this paper focuses on the improvement of both matching step effectiveness and its computational cost. Such alternative approach aims to greatly enhance matching step by exploiting the geometric properties of a pair of stereoscopic images. In this way we significantly reduce the complexity of the method without affecting results in terms of quality.

  11. Digital stereoscopic convergence where video games and movies for the home user meet

    NASA Astrophysics Data System (ADS)

    Schur, Ethan

    2009-02-01

    Today there is a proliferation of stereoscopic 3D display devices, 3D content, and 3D enabled video games. As we in the S-3D community bring stereoscopic 3D to the home user we have a real opportunity of using stereoscopic 3D to bridge the gap between exciting immersive games and home movies. But to do this, we cannot limit ourselves to current conceptions of gaming and movies. We need, for example, to imagine a movie that is fully rendered using avatars in a stereoscopic game environment. Or perhaps to imagine a pervasive drama where viewers can play too and become an essential part of the drama - whether at home or on the go on a mobile platform. Stereoscopic 3D is the "glue" that will bind these video and movie concepts together. As users feel more immersed, the lines between current media will blur. This means that we have the opportunity to shape the way that we, as humans, view and interact with each other, our surroundings and our most fundamental art forms. The goal of this paper is to stimulate conversation and further development on expanding the current gaming and home theatre infrastructures to support greatly-enhanced experiential entertainment.

  12. Effect of stereoscopic filming parameters and exposure duration on quality and naturalness judgements

    NASA Astrophysics Data System (ADS)

    IJsselsteijn, Wijnand A.; de Ridder, Huib; Vliegen, Joyce

    1999-05-01

    Previously we reported a study into the effect of stereoscopic filing parameters on perceived quality, naturalness and eye strain. In a pilot experiment, using 25 seconds exposure duration, a marked shift occurred between naturalness and quality ratings as a function of camera separation. This shift was less clearly present in the main experiment, in which we used an exposure duration of 5 seconds. This suggests a potential effect of exposure duration on observer appreciation of stereoscopic images. To further investigate this, we performed an experiment using exposure durations of both 5 and 10 seconds. For these durations, twelve observers rated naturalness of depth and quality of depth for stereoscopic still image varying in camera separation, convergence distance and focal length. The results showed no significant main effect of exposure duration. A small yet significant shift between naturalness and quality was found for both duration conditions. This result replicated earlier findings, indicating that this is a reliable effect, albeit content-dependent. A second experiment was performed with exposure durations ranging from 1 to 15 seconds. The result of this experiment showed a small yet significant effect of exposure duration. Whereas longer exposure durations do not have a negative impact on the appreciative scores of optimally reproduced stereoscopic images, observers do give lower judgments to monoscopic images and stereoscopic images with unnatural disparity values as exposure duration increases.

  13. Stereoscopic Machine-Vision System Using Projected Circles

    NASA Technical Reports Server (NTRS)

    Mackey, Jeffrey R.

    2010-01-01

    A machine-vision system capable of detecting obstacles large enough to damage or trap a robotic vehicle is undergoing development. The system includes (1) a pattern generator that projects concentric circles of laser light forward onto the terrain, (2) a stereoscopic pair of cameras that are aimed forward to acquire images of the circles, (3) a frame grabber and digitizer for acquiring image data from the cameras, and (4) a single-board computer that processes the data. The system is being developed as a prototype of machine- vision systems to enable robotic vehicles ( rovers ) on remote planets to avoid craters, large rocks, and other terrain features that could capture or damage the vehicles. Potential terrestrial applications of systems like this one could include terrain mapping, collision avoidance, navigation of robotic vehicles, mining, and robotic rescue. This system is based partly on the same principles as those of a prior stereoscopic machine-vision system in which the cameras acquire images of a single stripe of laser light that is swept forward across the terrain. However, this system is designed to afford improvements over some of the undesirable features of the prior system, including the need for a pan-and-tilt mechanism to aim the laser to generate the swept stripe, ambiguities in interpretation of the single-stripe image, the time needed to sweep the stripe across the terrain and process the data from many images acquired during that time, and difficulty of calibration because of the narrowness of the stripe. In this system, the pattern generator does not contain any moving parts and need not be mounted on a pan-and-tilt mechanism: the pattern of concentric circles is projected steadily in the forward direction. The system calibrates itself by use of data acquired during projection of the concentric-circle pattern onto a known target representing flat ground. The calibration- target image data are stored in the computer memory for use as a

  14. Monocular and binocular edges enhance the perception of stereoscopic slant.

    PubMed

    Wardle, Susan G; Palmisano, Stephen; Gillam, Barbara J

    2014-07-01

    Gradients of absolute binocular disparity across a slanted surface are often considered the basis for stereoscopic slant perception. However, perceived stereo slant around a vertical axis is usually slow and significantly under-estimated for isolated surfaces. Perceived slant is enhanced when surrounding surfaces provide a relative disparity gradient or depth step at the edges of the slanted surface, and also in the presence of monocular occlusion regions (sidebands). Here we investigate how different kinds of depth information at surface edges enhance stereo slant about a vertical axis. In Experiment 1, perceived slant decreased with increasing surface width, suggesting that the relative disparity between the left and right edges was used to judge slant. Adding monocular sidebands increased perceived slant for all surface widths. In Experiment 2, observers matched the slant of surfaces that were isolated or had a context of either monocular or binocular sidebands in the frontal plane. Both types of sidebands significantly increased perceived slant, but the effect was greater with binocular sidebands. These results were replicated in a second paradigm in which observers matched the depth of two probe dots positioned in front of slanted surfaces (Experiment 3). A large bias occurred for the surface without sidebands, yet this bias was reduced when monocular sidebands were present, and was nearly eliminated with binocular sidebands. Our results provide evidence for the importance of edges in stereo slant perception, and show that depth from monocular occlusion geometry and binocular disparity may interact to resolve complex 3D scenes. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Effects of Stereoscopic Depth on Vigilance Performance and Cerebral Hemodynamics.

    PubMed

    Greenlee, Eric T; Funke, Gregory J; Warm, Joel S; Finomore, Victor S; Patterson, Robert E; Barnes, Laura E; Funke, Matthew E; Vidulich, Michael A

    2015-09-01

    We tested the possibility that monitoring a display wherein critical signals for detection were defined by a stereoscopic three-dimensional (3-D) image might be more resistant to the vigilance decrement, and to temporal declines in cerebral blood flow velocity (CBFV), than monitoring a display featuring a customary two-dimensional (2-D) image. Hancock has asserted that vigilance studies typically employ stimuli for detection that do not exemplify those that occur in the natural world. As a result, human performance is suboptimal. From this perspective, tasks that better approximate perception in natural environments should enhance performance efficiency. To test that possibility, we made use of stereopsis, an important means by which observers interact with their everyday surroundings. Observers monitored a circular display in which a vertical line was embedded. Critical signals for detection in a 2-D condition were instances in which the line was rotated clockwise from vertical. In a 3-D condition, critical signals were cases in which the line appeared to move outward toward the observer. The overall level of signal detection and the stability of detection over time were greater when observers monitored for 3-D changes in target depth compared to 2-D changes in target orientation. However, the 3-D display did not retard the temporal decline in CBFV. These results provide the initial demonstration that 3-D displays can enhance performance in vigilance tasks. The use of 3-D displays may be productive in augmenting system reliability when operator vigilance is vital. © 2015, Human Factors and Ergonomics Society.

  16. Doing Textiles Experiments in Game-Based Virtual Reality: A Design of the Stereoscopic Chemical Laboratory (SCL) for Textiles Education

    ERIC Educational Resources Information Center

    Lau, Kung Wong; Kan, Chi Wai; Lee, Pui Yuen

    2017-01-01

    Purpose: The purpose of this paper is to discuss the use of stereoscopic virtual technology in textile and fashion studies in particular to the area of chemical experiment. The development of a designed virtual platform, called Stereoscopic Chemical Laboratory (SCL), is introduced. Design/methodology/approach: To implement the suggested…

  17. The compressed average image intensity metric for stereoscopic video quality assessment

    NASA Astrophysics Data System (ADS)

    Wilczewski, Grzegorz

    2016-09-01

    The following article depicts insights towards design, creation and testing of a genuine metric designed for a 3DTV video quality evaluation. The Compressed Average Image Intensity (CAII) mechanism is based upon stereoscopic video content analysis, setting its core feature and functionality to serve as a versatile tool for an effective 3DTV service quality assessment. Being an objective type of quality metric it may be utilized as a reliable source of information about the actual performance of a given 3DTV system, under strict providers evaluation. Concerning testing and the overall performance analysis of the CAII metric, the following paper presents comprehensive study of results gathered across several testing routines among selected set of samples of stereoscopic video content. As a result, the designed method for stereoscopic video quality evaluation is investigated across the range of synthetic visual impairments injected into the original video stream.

  18. Comparison of form in potential functions while maintaining upright posture during exposure to stereoscopic video clips.

    PubMed

    Kutsuna, Kenichiro; Matsuura, Yasuyuki; Fujikake, Kazuhiro; Miyao, Masaru; Takada, Hiroki

    2013-01-01

    Visually induced motion sickness (VIMS) is caused by sensory conflict, the disagreement between vergence and visual accommodation while observing stereoscopic images. VIMS can be measured by psychological and physiological methods. We propose a mathematical methodology to measure the effect of three-dimensional (3D) images on the equilibrium function. In this study, body sway in the resting state is compared with that during exposure to 3D video clips on a liquid crystal display (LCD) and on a head mounted display (HMD). In addition, the Simulator Sickness Questionnaire (SSQ) was completed immediately afterward. Based on the statistical analysis of the SSQ subscores and each index for stabilograms, we succeeded in determining the quantity of the VIMS during exposure to the stereoscopic images. Moreover, we discuss the metamorphism in the potential functions to control the standing posture during the exposure to stereoscopic video clips.

  19. Design of stereoscopic viewing system based on a compact mirror and dual monitor

    NASA Astrophysics Data System (ADS)

    Wu, Hsien-Huang P.; Chang, Shih-Hsin

    2010-02-01

    Stereoscopic technologies continue to accelerate the adoption of 3-D in both professional and consumer applications. Stereo 3-D displays have the potential to benefit geospatial intelligence, complex visualization, pharmaceutical development, petroleum exploration, medicine, entertainment, architecture, simulation, and other difficult tasks. A single-mirror dual monitor stereoscope system that can offer the full resolution of the current LCD display for 3-D viewing is proposed. This new approach utilizes an isosceles trapezoid mirror and two monitors to provide a cost-effective approach for stereoscopic viewing. Mathematical formulas for the design of the compact mirror were derived based on a novel scheme, and an implementation of the system was conducted to verify the practicability of the proposed method. We believe its compactness, low cost, and high image quality can become a very competitive choice among various display techniques currently available.

  20. Lunar-Surface Closeup Stereoscopic Photography on the Sea of Tranquility (Apollo 11 Landing Site)

    NASA Technical Reports Server (NTRS)

    Greenwood, W. R.; Jones, R. L.; Heiken, G.; Bender, M.; Hill, R. O.

    1971-01-01

    Analysis of returned lunar samples provides limited information about lunar geology. To obtain information about in-place lunar material, a closeup stereoscopic camera capable of photographing small-scale surface features was built and was used at the Apollo 11 landing site. Stereoscopic photographs were taken of surface areas relative to the lunar module, and the surfaces photographed were analyzed. The photographs are classified into five groups: soil disturbed by astronaut activities, generally undisturbed soil, loose aggregate surface material, crater bottoms with prominent glass deposits, and hard rock deposits. Glass deposits in the returned samples are described for comparison with the features observed in the photographs. The stereoscopic photographs were of outstanding quality and show the nature of lunar-surface material in detail. Lunar topography was reconstructed from the photographs with an analytical plotter. The photography results indicate that the closeup composition and genesis of lunar soil at the Apollo 11 landing site.

  1. Synthetic phase holograms for auto-stereoscopic image displays using a modified IFTA

    NASA Astrophysics Data System (ADS)

    Choi, Kyongsik; Kim, Hwi; Lee, Byoungho

    2004-05-01

    A Fourier-transformed synthetic phase hologram for an auto-stereoscopic image display system is proposed and implemented. The system uses a phase-only spatial light modulator and a simple projection lens module. A modified iterative Fresnel transform algorithm method, for the reconstruction of gray-level quantized stereo images with fast convergence, high diffraction efficiency and large signal-to-noise ratio is also described. Using this method, it is possible to obtain a high diffraction efficiency(~90%), an excellent signal-to-noise ratio(> 9.6dB), and a short calculation time(~3min). Experimentally, the proposed auto-stereoscopic display system was able to generate stereoscopic 3D images very well.

  2. Synthetic phase holograms for auto-stereoscopic image displays using a modified IFTA.

    PubMed

    Choi, Kyongsik; Kim, Hwi; Lee, Byoungho

    2004-05-31

    A Fourier-transformed synthetic phase hologram for an auto-stereoscopic image display system is proposed and implemented. The system uses a phase-only spatial light modulator and a simple projection lens module. A modified iterative Fresnel transform algorithm method, for the reconstruction of gray-level quantized stereo images with fast convergence, high diffraction efficiency and large signal-to-noise ratio is also described. Using this method, it is possible to obtain a high diffraction efficiency(~90%), an excellent signal-to-noise ratio(> 9.6dB), and a short calculation time(~3min). Experimentally, the proposed auto-stereoscopic display system was able to generate stereoscopic 3D images very well.

  3. Assessment of visual-spatial skills in medical context tasks when using monoscopic and stereoscopic visualization

    NASA Astrophysics Data System (ADS)

    Martinez Escobar, Marisol; Juhnke, Bethany; Hisley, Kenneth; Eliot, David; Winer, Eliot

    2013-03-01

    The dramatic rise of digital medical imaging has allowed medical personnel to see inside their patients as never before. Many software products are now available to view this data in various 2D and 3D formats. This also raises many basic research questions on spatial perception for humans viewing these images. The work presented here attempts to answer the question: How would adding the stereopsis depth cue affect relative position tasks in a medical context? By designing and conducting a study to isolate the benefits between monoscopic 3D and stereoscopic 3D displays in a relative position task, the following hypothesis was tested: stereoscopic 3D displays are beneficial over monoscopic 3D displays for relative position judgment tasks in a medical visualization setting. The results show that stereoscopic condition yielded a higher score than the monoscopic condition, but the results were not always statistically significant.

  4. Initial experience with stereoscopic visualization of three-dimensional ultrasound data in surgery.

    PubMed

    Gronningsaeter, A; Lie, T; Kleven, A; Mørland, T; Langø, T; Unsgård, G; Myhre, H O; Mårvik, R

    2000-11-01

    Initial in vivo and in vitro experiments were performed to evaluate the feasibility of stereoscopically displaying three-dimensional (3D) ultrasound data from neurosurgery, laparoscopic surgery, and vascular surgery. Stereoscopic visualization was illustrated by four video sequences, which can be downloaded from http://www.us.unimed. sintef.no/. These sequences show a brain tumor, hepatic arteries in relation to the gallbladder, a model that mimics a neuroendoscope in a cyst, and a "flight" into model of an artery with an intima flap. The experiments indicate that stereoscopic display of ultrasound data is feasible when there is sufficient contrast between the objects of interest and the surrounding tissue. True 3D vision improves perception, thus enhancing the ability to understand complex anatomic structures such as irregular lesions and tortuous vessels.

  5. Computer-generated holograms of a real three-dimensional object based on stereoscopic video images.

    PubMed

    Kim, Seung-Cheol; Hwang, Dong-Choon; Lee, Dong-Hwi; Kim, Eun-Soo

    2006-08-01

    A novel method of using stereoscopic video images to synthesize the computer-generated hologram (CGH) patterns of a real 3D object is proposed. Stereoscopic video images of a real 3D object are captured by a 3D camera system. Disparity maps between the captured stereo image pairs are estimated and from these estimated maps the depth data for each pixel of the object can be extracted on a frame basis. By using these depth data and original color images, hologram patterns of a real object can be computationally generated. In experiments, stereoscopic video images of a real 3D object, a wooden rhinoceros doll, are captured by using the Wasol 3D adapter system and its depth data are extracted from them. Then, CGH patterns of 1280 pixels x 1024 pixels are generated with these depth-annotated images of the wooden rhinoceros doll, and the CGH patterns are experimentally displayed via a holographic display system.

  6. The effect of sound on visual fidelity perception in stereoscopic 3-D.

    PubMed

    Rojas, David; Kapralos, Bill; Hogue, Andrew; Collins, Karen; Nacke, Lennart; Cristancho, Sayra; Conati, Cristina; Dubrowski, Adam

    2013-12-01

    Visual and auditory cues are important facilitators of user engagement in virtual environments and video games. Prior research supports the notion that our perception of visual fidelity (quality) is influenced by auditory stimuli. Understanding exactly how our perception of visual fidelity changes in the presence of multimodal stimuli can potentially impact the design of virtual environments, thus creating more engaging virtual worlds and scenarios. Stereoscopic 3-D display technology provides the users with additional visual information (depth into and out of the screen plane). There have been relatively few studies that have investigated the impact that auditory stimuli have on our perception of visual fidelity in the presence of stereoscopic 3-D. Building on previous work, we examine the effect of auditory stimuli on our perception of visual fidelity within a stereoscopic 3-D environment.

  7. Lunar Surface Closeup Stereoscopic Photography on the Ocean of Storms (Apollo 12 Landing Site)

    NASA Technical Reports Server (NTRS)

    Heiken, G.; Carrier, W. D., III

    1971-01-01

    To obtain information about in-place lunar rocks and soil, a closeup stereoscopic camera capable of photographing small scale surface features was used at the Apollo 12 landing site on the Ocean of Storms. Fifteen stereoscopic photograph pairs were obtained. The stereoscopic pairs were of excellent quality and showed the in-place lunar material in detail. The photographs were analyzed and the results compared with the results of the Apollo 12 core sample analysis and other investigations. Significant information about the physical composition and genesis of the lunar soil at the Apollo 12 landing site was obtained. The cohesive soil on the Ocean of Storms probably results from repetitive bombardment of basalt flows by meteorites over long periods of time.

  8. Quantitative evaluation of perspective and stereoscopic displays in three-axis manual tracking tasks

    NASA Technical Reports Server (NTRS)

    Ellis, Stephen R.; Tyler, Mitchelle E.; Hannaford, Blake; Stark, Lawrence W.; Kim, Won S.

    1987-01-01

    Optimal presentation of three-dimensional information on a two-dimensional display screen requires careful design of the projection to the display surface. Monoscopic perspective projection alone is usually not sufficient to represent three-dimensional spatial information. It can, however, be improved by the adjustment of perspective parameters and by geometric visual enhancements such as reference lines and a background grid. Stereoscopic display is another method of providing three-dimensional information to the human operator. Two experiments are performed with three-axis manual tracking tasks. The first experiment investigates the effects of perspective parameters on tracking performance. The second experiment investigates the effects of visual enhancements for both monoscopic and stereoscopic displays. Results indicate that, although stereoscopic displays do generally permit superior tracking performance, monoscopic displays can allow equivalent performance when they are defined with optimal perspective parameters and provided with adequate visual enhancements.

  9. [Effects of stereoscopic cultivation on soil microorganism, enzyme activity and the agronomic characters of Panax notoginseng].

    PubMed

    Liao, Pei-ran; Cui, Xiu-ming; Lan, Lei; Chen, Wei-dong; Wang, Cheng-xiao; Yang, Xiao-yan; Liu, Da-hui; Yang, Ye

    2015-08-01

    Compartments of soil microorganism and enzymes between stereoscopic cultivation (three storeys) and field cultivation (CK) of Panax notoginseng were carried out, and the effects on P. notoginseng agronomic characters were also studied. Results show that concentration of soil microorganism of stereoscopic cultivation was lower than field cultivation; the activity of soil urea enzyme, saccharase and neutral phosphatase increased from lower storey to upper storey; the activity of soil urea enzyme and saccharase of lower and upper storeys were significantly lower than CK; agronomic characters of stereoscopic cultivated P. notoginsengin were inferior to field cultivation, the middle storey with the best agronomic characters among the three storeys. The correlation analysis showed that fungi, actinomycetes and neutral phosphatase were significantly correlated with P. notoginseng agronomic characters; concentration of soil fungi and bacteria were significantly correlated with the soil relative water content; actinomycete and neutral phosphatase were significantly correlated with soil pH and relative water content, respectively; the activities of soil urea enzyme and saccharase were significantly correlated with the soil daily maximum temperature difference. Inconclusion, The current research shows that the imbalance of soil microorganism and the acutely changing of soil enzyme activity were the main reasons that caused the agronomic characters of stereoscopic cultivated P. notoginseng were worse than field cultivation. Thus improves the concentration of soil microorganism and enzyme activity near to field soil by improving the structure of stereoscopic cultivation is very important. And it was the direction which we are endeavoring that built better soil ecological environment for P. notoginseng of stereoscopic cultivation.

  10. Stereoscopic three-dimensional visualization applied to multimodal brain images: clinical applications and a functional connectivity atlas.

    PubMed

    Rojas, Gonzalo M; Gálvez, Marcelo; Vega Potler, Natan; Craddock, R Cameron; Margulies, Daniel S; Castellanos, F Xavier; Milham, Michael P

    2014-01-01

    Effective visualization is central to the exploration and comprehension of brain imaging data. While MRI data are acquired in three-dimensional space, the methods for visualizing such data have rarely taken advantage of three-dimensional stereoscopic technologies. We present here results of stereoscopic visualization of clinical data, as well as an atlas of whole-brain functional connectivity. In comparison with traditional 3D rendering techniques, we demonstrate the utility of stereoscopic visualizations to provide an intuitive description of the exact location and the relative sizes of various brain landmarks, structures and lesions. In the case of resting state fMRI, stereoscopic 3D visualization facilitated comprehension of the anatomical position of complex large-scale functional connectivity patterns. Overall, stereoscopic visualization improves the intuitive visual comprehension of image contents, and brings increased dimensionality to visualization of traditional MRI data, as well as patterns of functional connectivity.

  11. Design of multi-view stereoscopic HD video transmission system based on MPEG-21 digital item adaptation

    NASA Astrophysics Data System (ADS)

    Lee, Seokhee; Lee, Kiyoung; Kim, Man Bae; Kim, JongWon

    2005-11-01

    In this paper, we propose a design of multi-view stereoscopic HD video transmission system based on MPEG-21 Digital Item Adaptation (DIA). It focuses on the compatibility and scalability to meet various user preferences and terminal capabilities. There exist a large variety of multi-view 3D HD video types according to the methods for acquisition, display, and processing. By following the MPEG-21 DIA framework, the multi-view stereoscopic HD video is adapted according to user feedback. A user can be served multi-view stereoscopic video which corresponds with his or her preferences and terminal capabilities. In our preliminary prototype, we verify that the proposed design can support two deferent types of display device (stereoscopic and auto-stereoscopic) and switching viewpoints between two available viewpoints.

  12. Stereoscopic three-dimensional visualization applied to multimodal brain images: clinical applications and a functional connectivity atlas

    PubMed Central

    Rojas, Gonzalo M.; Gálvez, Marcelo; Vega Potler, Natan; Craddock, R. Cameron; Margulies, Daniel S.; Castellanos, F. Xavier; Milham, Michael P.

    2014-01-01

    Effective visualization is central to the exploration and comprehension of brain imaging data. While MRI data are acquired in three-dimensional space, the methods for visualizing such data have rarely taken advantage of three-dimensional stereoscopic technologies. We present here results of stereoscopic visualization of clinical data, as well as an atlas of whole-brain functional connectivity. In comparison with traditional 3D rendering techniques, we demonstrate the utility of stereoscopic visualizations to provide an intuitive description of the exact location and the relative sizes of various brain landmarks, structures and lesions. In the case of resting state fMRI, stereoscopic 3D visualization facilitated comprehension of the anatomical position of complex large-scale functional connectivity patterns. Overall, stereoscopic visualization improves the intuitive visual comprehension of image contents, and brings increased dimensionality to visualization of traditional MRI data, as well as patterns of functional connectivity. PMID:25414626

  13. Crosstalk reduction in auto-stereoscopic projection 3D display system.

    PubMed

    Lee, Kwang-Hoon; Park, Youngsik; Lee, Hyoung; Yoon, Seon Kyu; Kim, Sung-Kyu

    2012-08-27

    In auto-stereoscopic multi-views 3D display systems, the crosstalk and low resolution become problems for taking a clear depth image with the sufficient motion parallax. To solve these problems, we propose the projection-type auto-stereoscopic multi-view 3D display system, in which the hybrid optical system with the lenticular-parallax barrier and multi projectors. Condensing width of the projected unit-pixel image within the lenslet by hybrid optics is the core concept in this proposal. As the result, the point crosstalk is improved 53% and resolution is increased up to 5 times.

  14. A Simple Quality Assessment Index for Stereoscopic Images Based on 3D Gradient Magnitude

    PubMed Central

    Wang, Shanshan; Shao, Feng; Li, Fucui; Yu, Mei; Jiang, Gangyi

    2014-01-01

    We present a simple quality assessment index for stereoscopic images based on 3D gradient magnitude. To be more specific, we construct 3D volume from the stereoscopic images across different disparity spaces and calculate pointwise 3D gradient magnitude similarity (3D-GMS) along three horizontal, vertical, and viewpoint directions. Then, the quality score is obtained by averaging the 3D-GMS scores of all points in the 3D volume. Experimental results on four publicly available 3D image quality assessment databases demonstrate that, in comparison with the most related existing methods, the devised algorithm achieves high consistency alignment with subjective assessment. PMID:25133265

  15. Instant noodle consumption is associated with cardiometabolic risk factors among college students in Seoul

    PubMed Central

    Huh, In Sil; Kim, Hyesook; Jo, Hee Kyung; Lim, Chun Soo; Kim, Jong Seung; Kim, Soo Jin; Kwon, Oran

    2017-01-01

    BACKGROUND/OBJECTIVES Increased consumption of instant noodles has recently been reported to be positively associated with obesity and cardiometabolic syndrome in South Korea, which has the highest per capita instant noodle consumption worldwide. This study aimed to investigate the association between instant noodle consumption and cardiometabolic risk factors among college students in Seoul. SUBJECTS/METHODS The study subjects consisted of 3,397 college students (1,782 male; 1,615 female) aged 18-29 years who participated in a health checkup. Information on instant noodle consumption was obtained from the participants' answers to a question about their average frequency of instant noodle intake over the 1 year period prior to the survey. RESULTS Statistical analysis using a general linear model that adjusted for age, body mass index, gender, family income, health-related behaviors, and other dietary factors important for cardiometabolic risk, showed a positive association between the frequency of instant noodle consumption and plasma triglyceride levels, diastolic blood pressure, and fasting blood glucose levels in all subjects. Compared to the group with the lowest frequency of instant noodle intake (≤ 1/month), the odds ratio for hypertriglyceridemia in the group with an intake of ≥ 3/week was 2.639 [95% confidence interval (CI), 1.393–5.000] for all subjects, while it was 2.149 (95% CI, 1.045–4.419) and 5.992 (95% CI, 1.859–21.824) for male and female students, respectively. In female students, diastolic blood pressure was also higher among more frequent consumers of instant noodles. CONCLUSIONS Our results suggest that frequent consumption of instant noodles may be associated with increased cardiometabolic risk factors among apparently healthy college students aged 18–29 years. PMID:28584580

  16. Instant noodle consumption is associated with cardiometabolic risk factors among college students in Seoul.

    PubMed

    Huh, In Sil; Kim, Hyesook; Jo, Hee Kyung; Lim, Chun Soo; Kim, Jong Seung; Kim, Soo Jin; Kwon, Oran; Oh, Bumjo; Chang, Namsoo

    2017-06-01

    Increased consumption of instant noodles has recently been reported to be positively associated with obesity and cardiometabolic syndrome in South Korea, which has the highest per capita instant noodle consumption worldwide. This study aimed to investigate the association between instant noodle consumption and cardiometabolic risk factors among college students in Seoul. The study subjects consisted of 3,397 college students (1,782 male; 1,615 female) aged 18-29 years who participated in a health checkup. Information on instant noodle consumption was obtained from the participants' answers to a question about their average frequency of instant noodle intake over the 1 year period prior to the survey. Statistical analysis using a general linear model that adjusted for age, body mass index, gender, family income, health-related behaviors, and other dietary factors important for cardiometabolic risk, showed a positive association between the frequency of instant noodle consumption and plasma triglyceride levels, diastolic blood pressure, and fasting blood glucose levels in all subjects. Compared to the group with the lowest frequency of instant noodle intake (≤ 1/month), the odds ratio for hypertriglyceridemia in the group with an intake of ≥ 3/week was 2.639 [95% confidence interval (CI), 1.393-5.000] for all subjects, while it was 2.149 (95% CI, 1.045-4.419) and 5.992 (95% CI, 1.859-21.824) for male and female students, respectively. In female students, diastolic blood pressure was also higher among more frequent consumers of instant noodles. Our results suggest that frequent consumption of instant noodles may be associated with increased cardiometabolic risk factors among apparently healthy college students aged 18-29 years.

  17. Antitussive and immunomodulating activities of instant coffee arabinogalactan-protein.

    PubMed

    Nosáľová, G; Prisenžňáková, L; Paulovičová, E; Capek, P; Matulová, M; Navarini, L; Liverani, F Suggi

    2011-11-01

    A low molecular mass arabinogalactan-protein (AGP) composed of galactose and arabinose with a low protein content, isolated from the instant coffee powder of Coffea arabica beans, has been tested on antitussive (in vivo) and immunomodulating (ex vivo) activities. The results of antitussive tests revealed a significant dose dependant cough-suppressive effect of coffee AGP. It was observed 30 or 60 min after AGP administration and its efficacy lasted during the entire experiment course. Immunological tests showed that AGP affected some mediators of immunocompetent cells of immune system as TNF-α, IFN-γ and IL-2 cytokines. It seems that coffee AGP is a good inductor of both pro-inflammatory cytokines TNF-α and IFN-γ, however, less potent in TNF-α induction in comparison with that of β-D-glucan. Evident induction of TNF-α, IL-2 and IFN-γ cytokines, pro-TH1 polarization supports our conclusion about bio-immunological efficacy of AGP with an emphasis on the cellular immunity. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Determination of the moisture content of instant noodles: interlaboratory study.

    PubMed

    Hakoda, Akiko; Kasama, Hirotaka; Sakaida, Kenichi; Suzuki, Tadanao; Yasui, Akemi

    2006-01-01

    Determination of the moisture content of instant noodles, currently under discussion by the Codex Alimentarius Commission (CAC) requires 2 methods: one for fried noodles and the other for nonfried noodles. The method to determine the moisture content of fried noodles by drying at 105 degrees C for 2 h used in the Japanese Agricultural Standard (JAS) system of Japan can be applied to this purpose. In the present study, the JAS method for fried noodles was modified to be suitable for nonfried noodles by extending the drying time to 4 h. An interlaboratory study was conducted to evaluate interlaboratory performance statistics for these 2 methods. Ten participating laboratories each analyzed 5 test materials of fried and nonfried noodles as blind duplicates. After removal of outliers statistically, the repeatability (RSDr) and the reproducibility (RSD(R)) of these methods were 1.6-2.6 and 3.9-4.8% for fried noodles, and 0.3-1.5 and 1.3-2.9% for nonfried noodles, respectively.

  19. The utilization of patin fish head for instant stock paste

    NASA Astrophysics Data System (ADS)

    Hartanto, Gabriela Mawi; Rahmawati, Della; Puteri, Maria Gunawan

    2017-01-01

    Patin fish is a developing industries that produce 67% of waste which 33% is the head. High protein content in patin fish head (PFH) open an opportunity to produce something that has higher economic value and can be used as human consumption, which is stock. In this study, PFH hydrolysis with acid, enzyme and heat were observed for their yield of protein, in correlation to taste & national standard for stock. Enzyme hydrolysis is chosen as the selected method with the highest protein and soluble amino acid which is 18.78 ± 7.50 mg BSA equivalent / ml and 0.854 ± 4.35 mg Tyrosine eq / ml. The hydrolysate was made into stock by mixing with other ingredient by the help of Design Expert to create selected formula. The formula composition is fish hydrolysate 27.29%, salt 19.17%, caramel 18.52%, garlic 6%, pepper 3.104%, oil 18.52% and water 7.47%. This formula receive 7.13 value from hedonic scale 1-9, which means the formula like moderately based on overall acceptance. For 4 gram stock, 150 ml of water was chosen as the preferable dilution volume for the stock with ranking test. Total nitrogen of the instant stock paste with selected hydrolysis method and formula fulfill National Standard according to SNI No. 01-4218 with 0.077% nitrogen amount.

  20. Modulated perturbations from instant preheating after new ekpyrosis

    SciTech Connect

    Battefeld, Thorsten

    2008-03-15

    I present a mechanism to transfer the spectrum of perturbations in a scalar isocurvature field {xi} onto the matter content in the radiation era via modulated, instant preheating after ekpyrosis. In this setup, {xi} determines the coupling constant relevant for the decay of a preheat matter field into fermions. The resulting power spectrum is scale invariant if {xi} remains close to a scaling solution in new ekpyrotic models of the Universe; by construction the spectrum is independent of the detailed physics near the bounce. The process differs from the curvaton mechanism, which has been used recently to revive the ekpyrotic scenario, in that no peculiar behavior of {xi} shortly before or during the bounce is needed. In addition, a concrete and efficient realization of reheating after ekpyrosis is provided; this mechanism is not tied to ekpyrotic models, but could equally well be used in other setups, for instance inflationary ones. I estimate non-Gaussianities and find no additional contributions in the most simple realizations, in contrast to models using the curvaton mechanism.

  1. Injectable solid peptide hydrogel: shear-thinning and instant recovery

    NASA Astrophysics Data System (ADS)

    Yan, Congqi; Schneider, Joel; Pochan, Darrin

    2011-03-01

    Peptides were designed to fold into β -hairpins once exposed to physiological conditions and consequently self-assemble into rigid hydrogel. The network consists of branched and entangled 3nm-wide fibrils. These physical gels shear thin and flow under a proper shear stress but immediately recover back into solids on removal of stress with further rigidity restoring over time. To elucidate mechanisms of these physical properties, gel behavior during and after flow was investigated. Gel stiffness recovered immediately after shear, as well as gel stiffening over time post-recovery, were found dependent on shear rate and shear duration. From scattering measurements during flow, the gel network structure was observed unchanged from the static state at all shear rates investigated. Thus, the peptide gel networks fracture into gel domains (>200nm as determined by scattering) during shear thinning/flow but can instantly percolate back into a solid hydrogel after cessation of shear, stiffening further as particle boundaries relax. As these gels are essentially the same solid material, before and after shear, they offer great potential as well-defined, injectable carriers of biomedical therapies where a desired encapsulated therapeutic payload is delivered to an in vivo site by simple syringe injection.

  2. Using Instant Messaging Systems as a Platform for Electronic Voting

    NASA Astrophysics Data System (ADS)

    Meletiadou, Anastasia; Grimm, Rüdiger

    Many Instant Messaging (IM) systems like Skype or Spark offer ex tended services such as file sharing, VoIP, or a shared whiteboard. As the name suggests, IM applications are predominantly used for spontaneous text-based communication for private or business purposes. In this paper we explore their potential to serve as platforms for secure collaborative applications like electronic contract negotiation, e-payment or electronic voting. Such applications have to deal with challenges like time constraints (“instant” com munication is desired), integration of media channels and the absence of one uni fying “sphere of control” covering all participants. In this paper, we address these challenges by discussing one particular secure collaborative application: secure decision processes for small groups. We provide the following contribu tions: (1) we define three varying scenarios and corresponding security require ments (2) we present an IM-based architecture implementing these scenarios, in cluding a Video-based authentication mechanism, and (3) we discuss poten tial attack patterns.

  3. LC-MS/MS determination of acrylamide in instant noodles from supermarkets in the Hebei province of China.

    PubMed

    Yang, Li-Xin; Zhang, Gui-Xiang; Yang, Li-Xue; He, Yan

    2012-01-01

    Acrylamide (AA) concentrations in instant noodles (90 samples, covering 10 different brands) from Hebei Province of China were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The instant noodles were sampled from the southern and northern areas of Hebei Province (Shijiazhuang and Tangshan, respectively). The average content of AA for all 10 instant noodle brands was 6-145 µg/kg. The average content of AA in fried instant noodles was 4.47 times of those in non-fried ones, indicating the influence of the frying process. The average content of AA in instant noodles from Shijiazhuang was 1.64 times that of the samples from Tangshan (56 µg/kg). Eighty-four percent of the instant noodle samples in Hebei were contaminated with AA, with an average content of 80 µg/kg. These observations will be helpful for evaluating individual exposure to AA from instant noodles in China.

  4. 76 FR 69287 - National Instant Criminal Background Check System Section Agency Information Collection...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... Criminal Justice Information Services (CJIS) Division's National Instant Criminal Background Check System... Sherry L. Kuneff, Management and Program Analyst, FBI, Criminal Justice Information Services Division... of the department sponsoring the collection: Form Number: 1110-0043. Sponsor: Criminal Justice...

  5. Instant noodles as an antifriction device: making the BOP with PPP in PNG.

    PubMed

    Errington, Frederick; Fujikura, Tatsuro; Gewertz, Deborah

    2012-01-01

    Focusing primarily, but not exclusively, on urban and periurban Papua New Guinea (PNG), we discuss the significance of instant ramen noodles to those now known as the “bottom of the pyramid” (BOP). Although instant noodles are remarkable in that they are eaten by virtually everyone in the world, albeit in different amounts and for different reasons, they are marketed in PNG specifically as a “popularly positioned product” (PPP) for the BOP. Cheap, convenient, tasty, filling, and shelf stable, they are a modern addition to Sidney Mintz's classic “proletarian hunger killers” of sugar, tea, and coffee. But, we argue, instant noodles have a distinctive contemporary role: they do more than sustain the poor; they transform them into the aspiring consumers of the BOP. As such, instant noodles can be viewed as an antifriction device, greasing the skids of capitalism as it extends its reach.

  6. Organizational Learning Goes Virtual?: A Study of Employees' Learning Achievement in Stereoscopic 3D Virtual Reality

    ERIC Educational Resources Information Center

    Lau, Kung Wong

    2015-01-01

    Purpose: This study aims to deepen understanding of the use of stereoscopic 3D technology (stereo3D) in facilitating organizational learning. The emergence of advanced virtual technologies, in particular to the stereo3D virtual reality, has fundamentally changed the ways in which organizations train their employees. However, in academic or…

  7. What is 3D good for? A review of human performance on stereoscopic 3D displays

    NASA Astrophysics Data System (ADS)

    McIntire, John P.; Havig, Paul R.; Geiselman, Eric E.

    2012-06-01

    This work reviews the human factors-related literature on the task performance implications of stereoscopic 3D displays, in order to point out the specific performance benefits (or lack thereof) one might reasonably expect to observe when utilizing these displays. What exactly is 3D good for? Relative to traditional 2D displays, stereoscopic displays have been shown to enhance performance on a variety of depth-related tasks. These tasks include judging absolute and relative distances, finding and identifying objects (by breaking camouflage and eliciting perceptual "pop-out"), performing spatial manipulations of objects (object positioning, orienting, and tracking), and navigating. More cognitively, stereoscopic displays can improve the spatial understanding of 3D scenes or objects, improve memory/recall of scenes or objects, and improve learning of spatial relationships and environments. However, for tasks that are relatively simple, that do not strictly require depth information for good performance, where other strong cues to depth can be utilized, or for depth tasks that lie outside the effective viewing volume of the display, the purported performance benefits of 3D may be small or altogether absent. Stereoscopic 3D displays come with a host of unique human factors problems including the simulator-sickness-type symptoms of eyestrain, headache, fatigue, disorientation, nausea, and malaise, which appear to effect large numbers of viewers (perhaps as many as 25% to 50% of the general population). Thus, 3D technology should be wielded delicately and applied carefully; and perhaps used only as is necessary to ensure good performance.

  8. Shot Segmentation for Binocular Stereoscopic Video Based on Spatial-Temporal Feature Clustering

    NASA Astrophysics Data System (ADS)

    Duan, Feng-feng

    2016-12-01

    Shot segmentation is the key to content-based analysis, index and retrieval of binocular stereoscopic video. To solve the problem of low accuracy of stereoscopic video shot segmentation in which the segmentation method of 2D video is used to segment monocular video sequence, and the disadvantages of some stereoscopic video shot segmentation methods, a shot segmentation method for binocular stereoscopic video based on spatial-temporal feature clustering (STFC) is proposed. In the method, the features of color and brightness of left video frames in temporal domain as well as the depth feature acquired by matching of left and right frames in spatial domain is extracted. The feature differences between frames are calculated and quantified. Then the clustering of feature differences in three-dimensional space is executed, and the optimization and iteration of the classes are implemented to achieve the division of shot boundary. The experimental results show that the proposed method can effectively solve the problems of error and omission, especially the inaccuracy of smooth shot detection in binocular stereo video shot segmentation when compared with the latest existing algorithm. The higher accuracy of segmentation can be achieved.

  9. A novel technique for infant length measurement based on stereoscopic vision.

    PubMed

    Sokolover, Nir; Phillip, Moshe; Sirota, Lea; Potruch, Amalia; Kiryati, Nahum; Klinger, Gil; Merlob, Paul

    2014-07-01

    Monitoring infant growth is essential for evaluation of development and is an important indicator of health and illness. Length is an essential indicator of infant growth, however, length measurement methods suffer from limitations which restrict their use. To improve infant length measurement by development of a novel, accurate, precise and practical measurement technique. A new system based on stereoscopic vision was developed. The system is comprised of two digital still cameras combined with software that calculates the infant's length from two simultaneously taken pictures. Length measurements of 54 healthy newborns were performed using a standard length board and the stereoscopic system. The two measurement methods were compared. Mean infant length was 473.1 (SD=29.1) mm versus 473.3 (SD=29.3) mm by length board and by the stereoscopic system, respectively. The mean difference between measurements was 0.2 (SD=2.5) mm and the mean of the absolute values of differences was 2.0 (SD=1.4) mm. Bland-Altman analysis showed good agreement between the two measurement methods. Precision of the new technique was demonstrated by a technical error of measurement of 2.57 mm. The stereoscopic system is accurate, reliable, easy to use, and involves less handling and discomfort to the newborns. It has the potential to measure premature infants or sick neonates through incubators.

  10. [Effect of Viewing a Long Stereoscopic Film on Equilibrium Function and Autonomic Nervous System].

    PubMed

    Kinoshita, Fumiya; Mori, Yuki; Sugiura, Akihiro; Yamakawa, Tatsuya; Matsuura, Yasuyuki; Takada, Hiroki; Miyao, Masaru

    2016-01-01

    Owing to the recent rapid advancements in image processing and three-dimensional (3-D) technologies, stereoscopic images can now be viewed on television as well as in theaters and on gaming consoles among others. However, with these advancements, there have also been reports on motion sickness and asthenopia induced by viewing stereoscopic films. Human equilibrium function deteriorates when viewing stereoscopic films, which may lead to motion sickness; however, the exact cause of such motion sickness remains unknown. Therefore, as part of hygiene research that contributes to society, it is important to consider the safety of viewing virtual 3D contents. In this study, we investigated the effects of viewing 2-D/3-D video clips on the human body by stabilometry, electrogastrography (EGG), and subjective assessments. Seven subjects aged 22 to 24 viewed 2-D/3-D video clips for 60 min. A comparison of time series data obtained at rest shows a significant change in the EGG patterns 20 min after the start of viewing the video clips. Furthermore, sway values while viewing the 3-D video clips were considerably higher than those while viewing the 2-D video clips 60 min after the start of viewing. These findings show that the autonomic nervous system is affected first by long-term viewing of stereoscopic films, and the equilibrium function deteriorates gradually over the course of the exposure.

  11. Egocentric distance perception and performance of direct pointing in stereoscopic displays.

    PubMed

    Lin, Chiuhsiang J; Woldegiorgis, Bereket H

    2017-10-01

    In this study, the interaction performances and spatial perceptions in stereoscopic environments were investigated. The experiment compared direct user interactions during pointing at a target, which was continuously visible or presented briefly and disappeared, in both stereoscopic and real environments, at three parallax/depth levels. The position data, collected by a motion system, were used to compute accuracy, signed error, movement time, and throughput. The results showed inaccurate egocentric distance judgment in stereoscopic displays and accurate perceptions in the real world. The overall inaccuracy, which was overestimation of about 10 cm, was relatively better than that achieved in previous studies. The overestimation decreased as the egocentric distance increased. However, providing visual objects did not improve the accuracy. The study concluded that direct pointing could minimize the underestimation problems commonly reported in stereoscopic viewing studies and showed practical significance for developers to focus on incorporating more direct and natural human-virtual reality interactions for improved performance. The findings of this study provide insight towards the development of less expensive displays and their applications. Implications of this work and engineering solutions are also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Visual storytelling in 2D and stereoscopic 3D video: effect of blur on visual attention

    NASA Astrophysics Data System (ADS)

    Huynh-Thu, Quan; Vienne, Cyril; Blondé, Laurent

    2013-03-01

    Visual attention is an inherent mechanism that plays an important role in the human visual perception. As our visual system has limited capacity and cannot efficiently process the information from the entire visual field, we focus our attention on specific areas of interest in the image for detailed analysis of these areas. In the context of media entertainment, the viewers' visual attention deployment is also influenced by the art of visual storytelling. To this date, visual editing and composition of scenes in stereoscopic 3D content creation still mostly follows those used in 2D. In particular, out-of-focus blur is often used in 2D motion pictures and photography to drive the viewer's attention towards a sharp area of the image. In this paper, we study specifically the impact of defocused foreground objects on visual attention deployment in stereoscopic 3D content. For that purpose, we conducted a subjective experiment using an eyetracker. Our results bring more insights on the deployment of visual attention in stereoscopic 3D content viewing, and provide further understanding on visual attention behavior differences between 2D and 3D. Our results show that a traditional 2D scene compositing approach such as the use of foreground blur does not necessarily produce the same effect on visual attention deployment in 2D and 3D. Implications for stereoscopic content creation and visual fatigue are discussed.

  13. Organizational Learning Goes Virtual?: A Study of Employees' Learning Achievement in Stereoscopic 3D Virtual Reality

    ERIC Educational Resources Information Center

    Lau, Kung Wong

    2015-01-01

    Purpose: This study aims to deepen understanding of the use of stereoscopic 3D technology (stereo3D) in facilitating organizational learning. The emergence of advanced virtual technologies, in particular to the stereo3D virtual reality, has fundamentally changed the ways in which organizations train their employees. However, in academic or…

  14. Human factors issues in the design of stereo-rendered photorealistic objects: a stereoscopic Turing test

    NASA Astrophysics Data System (ADS)

    Brack, Collin D.; Clewlow, John C.; Kessel, Ivan

    2010-02-01

    We present visual acuity metrics, human factors issues, and technical considerations in the construction of a stereorendered reality test in the spirit of the Turing test, Alan Turing's famous artificial intelligence test designed to explore the boundaries between human and machine interaction. The overall aim of this work is to provide guiding principles in the design of a stereoscopic reality test.

  15. Disparity profiles in 3DV applications: overcoming the issue of heterogeneous viewing conditions in stereoscopic delivery

    NASA Astrophysics Data System (ADS)

    Boisson, Guillaume; Chamaret, Christel

    2012-03-01

    More and more numerous 3D movies are released each year. Thanks to the current spread of 3D-TV displays, these 3D Video (3DV) contents are about to enter massively the homes. Yet viewing conditions determine the stereoscopic features achievable for 3DV material. Because the conditions at home - screen size and distance to screen - differ significantly from a theater, 3D Cinema movies need to be repurposed before broadcast and replication on 3D Blu-ray Discs for being fully enjoyed at home. In that paper we tackle that particular issue of how to handle the variety of viewing conditions in stereoscopic contents delivery. To that extend we first investigate what is basically at stake for granting stereoscopic viewers' comfort, through the well-known - and sometimes dispraised - vergence-accommodation conflict. Thereby we define a set of basic rules that can serve as guidelines for 3DV creation. We propose disparity profiles as new requirements for 3DV production and repurposing. Meeting proposed background and foreground constraints prevents from visual fatigue, and occupying the whole depth budget available grants optimal 3D effects. We present an efficient algorithm for automatic disparity-based 3DV retargeting depending on the viewing conditions. Variants are proposed depending on the input format (stereoscopic binocular content or depth-based format) and the level of complexity achievable.

  16. Stereoscopic video analysis of Anopheles gambiae behavior in the field: challenges and opportunities

    USDA-ARS?s Scientific Manuscript database

    Advances in our ability to localize and track individual swarming mosquitoes in the field via stereoscopic image analysis have enabled us to test long standing ideas about individual male behavior and directly observe coupling. These studies further our fundamental understanding of the reproductive ...

  17. Quality Assessment of Perceptual Crosstalk on Two-View Auto-Stereoscopic Displays.

    PubMed

    Kim, Jongyoo; Kim, Taewan; Lee, Sanghoon; Bovik, Alan Conrad

    2017-10-01

    Crosstalk is one of the most severe factors affecting the perceived quality of stereoscopic 3D images. It arises from a leakage of light intensity between multiple views, as in auto-stereoscopic displays. Well-known determinants of crosstalk include the co-location contrast and disparity of the left and right images, which have been dealt with in prior studies. However, when a natural stereo image that contains complex naturalistic spatial characteristics is viewed on an auto-stereoscopic display, other factors may also play an important role in the perception of crosstalk. Here, we describe a new way of predicting the perceived severity of crosstalk, which we call the Binocular Perceptual Crosstalk Predictor (BPCP). BPCP uses measurements of three complementary 3D image properties (texture, structural duplication, and binocular summation) in combination with two well-known factors (co-location contrast and disparity) to make predictions of crosstalk on two-view auto-stereoscopic displays. The new BPCP model includes two masking algorithms and a binocular pooling method. We explore a new masking phenomenon that we call duplicated structure masking, which arises from structural correlations between the original and distorted objects. We also utilize an advanced binocular summation model to develop a binocular pooling algorithm. Our experimental results indicate that BPCP achieves high correlations against subjective test results, improving upon those delivered by previous crosstalk prediction models.

  18. Effect of reduced stereoscopic camera separation on ring placement with a surgical telerobot

    NASA Astrophysics Data System (ADS)

    Ellis, Stephen R.; Fishman, Jonathan M.; Hasser, Christopher J.; Stern, John D.

    2005-03-01

    A custom, stereoscopic video camera was built to study the impact of decreased camera separation on a stereoscopically viewed, visual-manual task resembling some aspects of surgery. The camera"s field of view was matched to that of a stereoscopic laparoscope by adjusting focal length and viewing distance so that the viewer could see equivalent image content at a plane orthogonal to their view. This plane contained the point at which the left and right viewing axes converged. This geometry only exactly matches the images from both the laparoscope and the stereo-camera at this point. This condition was considered a useful approximation for a match between the two image sources. Twelve naive subjects and one of the experimenters were first trained in a ring placement task using the stereo-laparoscope and subsequently switched to the stereo-camera. It was used with differing camera separations ranging from 100% of the laparoscope"s separation to a biocular view corresponding to no separation. The results suggest that camera separation may be reduced 20-35% without appreciably degrading user performance. Even a 50% reduction in separation shows stereoscopically supported performance much better than the biocular condition. The results suggest that existing laparoscopes which use 5 mm camera separation may well be significantly miniaturized without causing substantial performance degradation.

  19. Guidance for horizontal image translation (HIT) of high definition stereoscopic video production

    NASA Astrophysics Data System (ADS)

    Broberg, David K.

    2011-03-01

    Horizontal image translation (HIT) is an electronic process for shifting the left-eye and right-eye images horizontally as a way to alter the stereoscopic characteristics and alignment of 3D content after signals have been captured by stereoscopic cameras. When used cautiously and with full awareness of the impact on other interrelated aspects of the stereography, HIT is a valuable tool in the post production process as a means to modify stereoscopic content for more comfortable viewing. Most commonly it is used to alter the zero parallax setting (ZPS), to compensate for stereo window violations or to compensate for excessive positive or negative parallax in the source material. As more and more cinematic 3D content migrates to television distribution channels the use of this tool will likely expand. Without proper attention to certain guidelines the use of HIT can actually harm the 3D viewing experience. This paper provides guidance on the most effective use and describes some of the interrelationships and trade-offs. The paper recommends the adoption of the cinematic 2K video format as a 3D source master format for high definition television distribution of stereoscopic 3D video programming.

  20. Stereoscopic imaging: filling disoccluded areas in depth image-based rendering

    NASA Astrophysics Data System (ADS)

    Vázquez, Carlos; Tam, Wa James; Speranza, Filippo

    2006-10-01

    Depth image based rendering (DIBR) is a method for converting 2D material to stereoscopic 3D. With DIBR, information contained in a gray-level (luminance intensity) depth map is used to shift pixels in the 2D image to generate a new image as if it were captured from a new viewpoint. The larger the shift (binocular parallax), the larger is the perceived depth of the generated stereoscopic pair. However, a major problem with DIBR is that the shifted pixels now occupy new positions and leave areas that they originally occupied "empty." These disoccluded regions have to be filled properly, otherwise they can degrade image quality. In this study we investigated different methods for filling these disoccluded regions: (a) Filling regions with a constant color, (b) filling regions with horizontal linear interpolation of values on the hole border, (c) solving the Laplace equation on the hole boundary and propagate the values inside the region, (d) horizontal extrapolation with depth information taken into account, (e) variational inpainting with depth information taken into account, and (f) preprocessing of the depth map to prevent disoccluded regions from appearing. The methods differed in the time required for computing and filling, and the appearance of the filled-in regions. We assessed the subjective image quality outcome for several stereoscopic test images in which the left-eye view was the source and the right-eye view was a rendered view, in line with suggestions in the literature for the asymmetrical coding of stereoscopic images.

  1. Subjective experiences of watching stereoscopic Avatar and U2 3D in a cinema

    NASA Astrophysics Data System (ADS)

    Pölönen, Monika; Salmimaa, Marja; Takatalo, Jari; Häkkinen, Jukka

    2012-01-01

    A stereoscopic 3-D version of the film Avatar was shown to 85 people who subsequently answered questions related to sickness, visual strain, stereoscopic image quality, and sense of presence. Viewing Avatar for 165 min induced some symptoms of visual strain and sickness, but the symptom levels remained low. A comparison between Avatar and previously published results for the film U2 3D showed that sickness and visual strain levels were similar despite the films' runtimes. The genre of the film had a significant effect on the viewers' opinions and sense of presence. Avatar, which has been described as a combination of action, adventure, and sci-fi genres, was experienced as more immersive and engaging than the music documentary U2 3D. However, participants in both studies were immersed, focused, and absorbed in watching the stereoscopic 3-D (S3-D) film and were pleased with the film environments. The results also showed that previous stereoscopic 3-D experience significantly reduced the amount of reported eye strain and complaints about the weight of the viewing glasses.

  2. Fusion Prevents the Redundant Signals Effect: Evidence from Stereoscopically Presented Stimuli

    ERIC Educational Resources Information Center

    Schroter, Hannes; Fiedler, Anja; Miller, Jeff; Ulrich, Rolf

    2011-01-01

    In a simple reaction time (RT) experiment, visual stimuli were stereoscopically presented either to one eye (single stimulation) or to both eyes (redundant stimulation), with brightness matched for single and redundant stimulations. Redundant stimulation resulted in two separate percepts when noncorresponding retinal areas were stimulated, whereas…

  3. YouDash3D: exploring stereoscopic 3D gaming for 3D movie theaters

    NASA Astrophysics Data System (ADS)

    Schild, Jonas; Seele, Sven; Masuch, Maic

    2012-03-01

    Along with the success of the digitally revived stereoscopic cinema, events beyond 3D movies become attractive for movie theater operators, i.e. interactive 3D games. In this paper, we present a case that explores possible challenges and solutions for interactive 3D games to be played by a movie theater audience. We analyze the setting and showcase current issues related to lighting and interaction. Our second focus is to provide gameplay mechanics that make special use of stereoscopy, especially depth-based game design. Based on these results, we present YouDash3D, a game prototype that explores public stereoscopic gameplay in a reduced kiosk setup. It features live 3D HD video stream of a professional stereo camera rig rendered in a real-time game scene. We use the effect to place the stereoscopic effigies of players into the digital game. The game showcases how stereoscopic vision can provide for a novel depth-based game mechanic. Projected trigger zones and distributed clusters of the audience video allow for easy adaptation to larger audiences and 3D movie theater gaming.

  4. Fusion Prevents the Redundant Signals Effect: Evidence from Stereoscopically Presented Stimuli

    ERIC Educational Resources Information Center

    Schroter, Hannes; Fiedler, Anja; Miller, Jeff; Ulrich, Rolf

    2011-01-01

    In a simple reaction time (RT) experiment, visual stimuli were stereoscopically presented either to one eye (single stimulation) or to both eyes (redundant stimulation), with brightness matched for single and redundant stimulations. Redundant stimulation resulted in two separate percepts when noncorresponding retinal areas were stimulated, whereas…

  5. Pseudolocal tomography

    DOEpatents

    Katsevich, Alexander J.; Ramm, Alexander G.

    1996-01-01

    Local tomographic data is used to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. The relative attenuation data is input to a pseudo-local tomography function, where the difference between the internal density and the pseudo-local tomography function is computed across the discontinuity. The pseudo-local tomography function outputs the location of the discontinuity and the difference in density between the first density and the second density.

  6. Evaluation of stereoscopic medical video content on an autostereoscopic display for undergraduate medical education

    NASA Astrophysics Data System (ADS)

    Ilgner, Justus F. R.; Kawai, Takashi; Shibata, Takashi; Yamazoe, Takashi; Westhofen, Martin

    2006-02-01

    Introduction: An increasing number of surgical procedures are performed in a microsurgical and minimally-invasive fashion. However, the performance of surgery, its possibilities and limitations become difficult to teach. Stereoscopic video has evolved from a complex production process and expensive hardware towards rapid editing of video streams with standard and HDTV resolution which can be displayed on portable equipment. This study evaluates the usefulness of stereoscopic video in teaching undergraduate medical students. Material and methods: From an earlier study we chose two clips each of three different microsurgical operations (tympanoplasty type III of the ear, endonasal operation of the paranasal sinuses and laser chordectomy for carcinoma of the larynx). This material was added by 23 clips of a cochlear implantation, which was specifically edited for a portable computer with an autostereoscopic display (PC-RD1-3D, SHARP Corp., Japan). The recording and synchronization of left and right image was performed at the University Hospital Aachen. The footage was edited stereoscopically at the Waseda University by means of our original software for non-linear editing of stereoscopic 3-D movies. Then the material was converted into the streaming 3-D video format. The purpose of the conversion was to present the video clips by a file type that does not depend on a television signal such as PAL or NTSC. 25 4th year medical students who participated in the general ENT course at Aachen University Hospital were asked to estimate depth clues within the six video clips plus cochlear implantation clips. Another 25 4th year students who were shown the material monoscopically on a conventional laptop served as control. Results: All participants noted that the additional depth information helped with understanding the relation of anatomical structures, even though none had hands-on experience with Ear, Nose and Throat operations before or during the course. The monoscopic

  7. ROC study of the effect of stereoscopic imaging on assessment of breast lesions.

    PubMed

    Chan, Heang-Ping; Goodsitt, Mitchell M; Helvie, Mark A; Hadjiiski, Lubomir M; Lydick, Justin T; Roubidoux, Marilyn A; Bailey, Janet E; Nees, Alexis; Blane, Caroline E; Sahiner, Berkman

    2005-04-01

    An observer performance study was conducted to evaluate the usefulness of assessing breast lesion characteristics with stereomammography. Stereoscopic image pairs of 158 breast biopsy tissue specimens were acquired with a GE Senographe 2000D full field digital mammography system using a 1.8x magnification geometry. A phantom-shift method equivalent to a stereo shift angle of +/- 3 degrees relative to a central axis perpendicular to the detector was used. For each specimen, two pairs of stereo images were taken at approximately orthogonal orientations. The specimens contained either a mass, microcalcifications, both, or normal tissue. Based on pathological analysis, 39.9% of the specimens were found to contain malignancy. The digital specimen radiographs were displayed on a high resolution MegaScan CRT monitor driven by a DOME stereo display board using in-house developed software. Five MQSA radiologists participated as observers. Each observer read the 316 specimen stereo image pairs in a randomized order. For each case, the observer first read the monoscopic image and entered his/her confidence ratings on the presence of microcalcifications and/or masses, margin status, BI-RADS assessment, and the likelihood of malignancy. The corresponding stereoscopic images were then displayed on the same monitor and were viewed through stereoscopic LCD glasses. The observer was free to change the ratings in every category after stereoscopic reading. The ratings of the observers were analyzed by ROC methodology. For the 5 MQSA radiologists, the average Az value for estimation of the likelihood of malignancy of the lesions improved from 0.70 for monoscopic reading to 0.72 (p=0.04) after stereoscopic reading, and the average Az value for the presence of microcalcifications improved from 0.95 to 0.96 (p=0.02). The Az value for the presence of masses improved from 0.80 to 0.82 after stereoscopic reading, but the difference fell short of statistical significance (p=0.08). The visual

  8. Development and quality evaluation of value added instant rab mixes.

    PubMed

    Mogra, Renu; Choudhry, Maya

    2014-06-01

    Rab is a traditional Rajasthani preparation prepared by boiling maize grits and or flour in buttermilk for 2-3 h. It is sour in taste with curd and cumin seed flavour and has thick soup like consistency. Two instant mixes of rab were developed using two types of curds prepared from two different culture combination (i) S. lactis + S. thermophilus + S. diacetylactis and (ii) L. bulgaricus + S. diacetylactis. Processed greengram dhal and spinach leaves powder were added to the mixes for their value addition. In all, six mixes were developed from two types of curd. The mixes were analysed for nutritional composition at zero month and sensory characteristics and shelf life was evaluated for 4 months. The rab mixes provided moisture 4.0-5.5 g; protein 15.1-17.6 g; carbohydrate 62.3-70.29 g; energy 357-394 kcal; fat 4.4-6.1 g; iron 3.15-3.89 mg and calcium 346-386 mg per 100 g of mixes. There was an increase in protein, ash, fiber and iron content of mixes through value addition. Sensory evaluation of rab reconstituted from mixes revealed that the scores ranged between 7 and 8 depicting that rab was liked very much. The mixes were free from coliforms and S.aureus bacteria and the counts for TVC, yeast and molds were within safe limits during storage of 4 months at 28-30°C and RH 55-65%.

  9. Chemical, Physicochemical, Nutritional, Microbiological, Sensory and Rehydration Characteristics of Instant Whole Beans (Phaseolus vulgaris)

    PubMed Central

    Ibarra-Zavala, Silvia Jazmin; Ramírez-Salas, Silvia Patricia; Rosas-Ulloa, Petra; Ramírez-Ramírez, José Carmen; Ulloa-Rangel, Blanca Estela

    2015-01-01

    Summary Instant whole beans obtained by drying at 25 °C were evaluated for their chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics. The proximal composition of instant whole beans was typical of this kind of food, whereas aw and L*, a* and b* values were 0.639, 98.55, –0.28 and –1.52, respectively. In instant whole beans, 75% of the essential amino acids had a value greater or equal to the reference standard for adult humans; the protein quality in terms of chemical score was 95%. Microbiological counts of aerobic mesophilic bacteria, moulds, yeasts and total coliforms of rehydrated instant whole beans were <10 CFU/g, whereas the scores for colour, flavour, texture and overall acceptability were 7.22, 7.68, 7.24 and 7.34, respectively, on a 1–9 hedonic scale. The logarithmic and Pilosof models showed close fits (R2>0.99) to the experimental data for drying of cooked beans and rehydration of instant whole beans, respectively. In the light of the chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics of instant whole beans found in this study, drying at 25 °C is recommended for the production of such food. PMID:27904331

  10. Chemical, Physicochemical, Nutritional, Microbiological, Sensory and Rehydration Characteristics of Instant Whole Beans (Phaseolus vulgaris).

    PubMed

    Ulloa, José Armando; Ibarra-Zavala, Silvia Jazmin; Ramírez-Salas, Silvia Patricia; Rosas-Ulloa, Petra; Ramírez-Ramírez, José Carmen; Ulloa-Rangel, Blanca Estela

    2015-03-01

    Instant whole beans obtained by drying at 25 °C were evaluated for their chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics. The proximal composition of instant whole beans was typical of this kind of food, whereas aw and L*, a* and b* values were 0.639, 98.55, -0.28 and -1.52, respectively. In instant whole beans, 75% of the essential amino acids had a value greater or equal to the reference standard for adult humans; the protein quality in terms of chemical score was 95%. Microbiological counts of aerobic mesophilic bacteria, moulds, yeasts and total coliforms of rehydrated instant whole beans were <10 CFU/g, whereas the scores for colour, flavour, texture and overall acceptability were 7.22, 7.68, 7.24 and 7.34, respectively, on a 1-9 hedonic scale. The logarithmic and Pilosof models showed close fits (R(2)>0.99) to the experimental data for drying of cooked beans and rehydration of instant whole beans, respectively. In the light of the chemical, physicochemical, nutritional, microbiological, sensory and rehydration characteristics of instant whole beans found in this study, drying at 25 °C is recommended for the production of such food.

  11. Seismic Tomography.

    ERIC Educational Resources Information Center

    Anderson, Don L.; Dziewonski, Adam M.

    1984-01-01

    Describes how seismic tomography is used to analyze the waves produced by earthquakes. The information obtained from the procedure can then be used to map the earth's mantle in three dimensions. The resulting maps are then studied to determine such information as the convective flow that propels the crustal plates. (JN)

  12. Seismic Tomography.

    ERIC Educational Resources Information Center

    Anderson, Don L.; Dziewonski, Adam M.

    1984-01-01

    Describes how seismic tomography is used to analyze the waves produced by earthquakes. The information obtained from the procedure can then be used to map the earth's mantle in three dimensions. The resulting maps are then studied to determine such information as the convective flow that propels the crustal plates. (JN)

  13. SEISVIZ3D: Stereoscopic system for the representation of seismic data - Interpretation and Immersion

    NASA Astrophysics Data System (ADS)

    von Hartmann, Hartwig; Rilling, Stefan; Bogen, Manfred; Thomas, Rüdiger

    2015-04-01

    The seismic method is a valuable tool for getting 3D-images from the subsurface. Seismic data acquisition today is not only a topic for oil and gas exploration but is used also for geothermal exploration, inspections of nuclear waste sites and for scientific investigations. The system presented in this contribution may also have an impact on the visualization of 3D-data of other geophysical methods. 3D-seismic data can be displayed in different ways to give a spatial impression of the subsurface.They are a combination of individual vertical cuts, possibly linked to a cubical portion of the data volume, and the stereoscopic view of the seismic data. By these methods, the spatial perception for the structures and thus of the processes in the subsurface should be increased. Stereoscopic techniques are e. g. implemented in the CAVE and the WALL, both of which require a lot of space and high technical effort. The aim of the interpretation system shown here is stereoscopic visualization of seismic data at the workplace, i.e. at the personal workstation and monitor. The system was developed with following criteria in mind: • Fast rendering of large amounts of data so that a continuous view of the data when changing the viewing angle and the data section is possible, • defining areas in stereoscopic view to translate the spatial impression directly into an interpretation, • the development of an appropriate user interface, including head-tracking, for handling the increased degrees of freedom, • the possibility of collaboration, i.e. teamwork and idea exchange with the simultaneous viewing of a scene at remote locations. The possibilities offered by the use of a stereoscopic system do not replace a conventional interpretation workflow. Rather they have to be implemented into it as an additional step. The amplitude distribution of the seismic data is a challenge for the stereoscopic display because the opacity level and the scaling and selection of the data have to

  14. Positron Emission Tomography - Computed Tomography (PET/CT)

    MedlinePlus

    ... Index A-Z Positron Emission Tomography - Computed Tomography (PET/CT) Positron emission tomography (PET) uses small amounts of ... CT)? What is Positron Emission Tomography – Computed Tomography (PET/CT) Scanning? Positron emission tomography, also called PET imaging ...

  15. Mastcam-Z: Designing a Geologic, Stereoscopic, and Multispectral Pair of Zoom Cameras for the NASA Mars 2020 Rover

    NASA Astrophysics Data System (ADS)

    Bell, J. F.; Maki, J. N.; Mehall, G. L.; Ravine, M. A.; Caplinger, M. A.; Mastcam-Z Team

    2016-10-01

    Mastcam-Z is a stereoscopic, multispectral imaging investigation selected for flight on the Mars 2020 rover mission. In this presentation we review our science goals and requirements and describe our CDR-level design and operational plans.

  16. How much camera separation should be used for the capture and presentation of 3D stereoscopic imagery on binocular HMDs?

    NASA Astrophysics Data System (ADS)

    McIntire, John; Geiselman, Eric; Heft, Eric; Havig, Paul

    2011-06-01

    Designers, researchers, and users of binocular stereoscopic head- or helmet-mounted displays (HMDs) face the tricky issue of what imagery to present in their particular displays, and how to do so effectively. Stereoscopic imagery must often be created in-house with a 3D graphics program or from within a 3D virtual environment, or stereoscopic photos/videos must be carefully captured, perhaps for relaying to an operator in a teleoperative system. In such situations, the question arises as to what camera separation (real or virtual) is appropriate or desirable for end-users and operators. We review some of the relevant literature regarding the question of stereo pair camera separation using deskmounted or larger scale stereoscopic displays, and employ our findings to potential HMD applications, including command & control, teleoperation, information and scientific visualization, and entertainment.

  17. Portable low-cost devices for videotaping, editing, and displaying field-sequential stereoscopic motion pictures and video

    NASA Astrophysics Data System (ADS)

    Starks, Michael R.

    1990-09-01

    A variety of low cost devices for capturing, editing and displaying field sequential 60 cycle stereoscopic video have recently been marketed by 3D TV Corp. and others. When properly used, they give very high quality images with most consumer and professional equipment. Our stereoscopic multiplexers for creating and editing field sequential video in NTSC or component(SVHS, Betacain, RGB) and Home 3D Theater system employing LCD eyeglasses have made 3D movies and television available to a large audience.

  18. Solar Tomography

    NASA Astrophysics Data System (ADS)

    Davila, J. M.

    1993-12-01

    Images obtained by observing the solar corona from a single spacecraft typically measure the line-of-sight integral of the volumetric emissivity through the source. The resulting two-dimensional observations have an unavoidable ambiguity along the line of sight that can be removed only by making assumptions about the three dimensional nature of the emission. These ambiguities can be removed by observing the Sun from different vantage points, at the same time, i.e. solar tomography. The basic concept of tomographic is fairly simple. For an optically thin emission source, like the solar corona, each pixel in an image represents the line of sight integration of the volumetric emissivity of the plasma at the wavelength of observation. By obtaining several of these observations, from various angles, the underlying three dimensional structure of the emission can be deduced. This principle has been used extensively in the Medical community for the imaging of internal structure of the body with such techniques as Computer Aided Tomography (CAT) scanners and Magnetic Resonance Imaging (MRI). The purpose of this paper is to take an intial look at the following two questions: (1) Is tomography feasible with a few spacecraft?; and (2) What scientific objectives can be addressed?

  19. Correlative Tomography

    PubMed Central

    Burnett, T. L.; McDonald, S. A.; Gholinia, A.; Geurts, R.; Janus, M.; Slater, T.; Haigh, S. J.; Ornek, C.; Almuaili, F.; Engelberg, D. L.; Thompson, G. E.; Withers, P. J.

    2014-01-01

    Increasingly researchers are looking to bring together perspectives across multiple scales, or to combine insights from different techniques, for the same region of interest. To this end, correlative microscopy has already yielded substantial new insights in two dimensions (2D). Here we develop correlative tomography where the correlative task is somewhat more challenging because the volume of interest is typically hidden beneath the sample surface. We have threaded together x-ray computed tomography, serial section FIB-SEM tomography, electron backscatter diffraction and finally TEM elemental analysis all for the same 3D region. This has allowed observation of the competition between pitting corrosion and intergranular corrosion at multiple scales revealing the structural hierarchy, crystallography and chemistry of veiled corrosion pits in stainless steel. With automated correlative workflows and co-visualization of the multi-scale or multi-modal datasets the technique promises to provide insights across biological, geological and materials science that are impossible using either individual or multiple uncorrelated techniques. PMID:24736640

  20. Correlative Tomography

    NASA Astrophysics Data System (ADS)

    Burnett, T. L.; McDonald, S. A.; Gholinia, A.; Geurts, R.; Janus, M.; Slater, T.; Haigh, S. J.; Ornek, C.; Almuaili, F.; Engelberg, D. L.; Thompson, G. E.; Withers, P. J.

    2014-04-01

    Increasingly researchers are looking to bring together perspectives across multiple scales, or to combine insights from different techniques, for the same region of interest. To this end, correlative microscopy has already yielded substantial new insights in two dimensions (2D). Here we develop correlative tomography where the correlative task is somewhat more challenging because the volume of interest is typically hidden beneath the sample surface. We have threaded together x-ray computed tomography, serial section FIB-SEM tomography, electron backscatter diffraction and finally TEM elemental analysis all for the same 3D region. This has allowed observation of the competition between pitting corrosion and intergranular corrosion at multiple scales revealing the structural hierarchy, crystallography and chemistry of veiled corrosion pits in stainless steel. With automated correlative workflows and co-visualization of the multi-scale or multi-modal datasets the technique promises to provide insights across biological, geological and materials science that are impossible using either individual or multiple uncorrelated techniques.

  1. Windows Instant Messaging App Forensics: Facebook and Skype as Case Studies

    PubMed Central

    Yang, Teing Yee; Dehghantanha, Ali; Choo, Kim-Kwang Raymond; Muda, Zaiton

    2016-01-01

    Instant messaging (IM) has changed the way people communicate with each other. However, the interactive and instant nature of these applications (apps) made them an attractive choice for malicious cyber activities such as phishing. The forensic examination of IM apps for modern Windows 8.1 (or later) has been largely unexplored, as the platform is relatively new. In this paper, we seek to determine the data remnants from the use of two popular Windows Store application software for instant messaging, namely Facebook and Skype on a Windows 8.1 client machine. This research contributes to an in-depth understanding of the types of terrestrial artefacts that are likely to remain after the use of instant messaging services and application software on a contemporary Windows operating system. Potential artefacts detected during the research include data relating to the installation or uninstallation of the instant messaging application software, log-in and log-off information, contact lists, conversations, and transferred files. PMID:26982207

  2. Volatile compounds and sensory characteristics of various instant teas produced from black tea.

    PubMed

    Kraujalytė, Vilma; Pelvan, Ebru; Alasalvar, Cesarettin

    2016-03-01

    Various instant teas produced differently from black tea [freeze-dried instant tea (FDIT), spray-dried instant tea (SDIT), and decaffeinated instant tea (DCIT)], were compared for their differences in volatile compounds as well as descriptive sensory analysis (DSA). A total of 63 volatile compounds in all tea samples (eight aldehydes, ten alcohols, nine ketones, five esters, eight acids, ten terpenes/terpenoids, ten furans/furanones, two pyrroles, and one miscellaneous compound) were tentatively identified. Black tea, FDIT, SDIT, and DCIT contained 60, 55, 47, and 40 volatile compounds, respectively. Ten flavour attributes such as after taste, astringency, bitter, caramel-like, floral/sweet, green/grassy, hay-like, malty, roasty, and seaweed were identified. Intensities for a number of flavour attributes (except for caramel-like in SDIT and bitter and after taste in DCIT) were not significantly different (p>0.05) among tea samples. The present study suggests that instant teas can also be used as good alternative to black tea.

  3. Effective Glottal Instant Detection and Electroglottographic Parameter Extraction for Automated Voice Pathology Assessment.

    PubMed

    Deshpande, Pranav; Manikandan, M Sabarimalai

    2017-01-17

    Accurate determination of glottal instants and electroglottographic (EGG) parameters is most important in voice pathology analysis including multiple voice disorders: neurological, functional, and laryngeal diseases. In this paper, we present a new effective method for reliable detection of glottal instants and EGG parameters from an EGG signal composed of voiced and non-voice segments. In the first stage, we present an adaptive variational mode decomposition (aVMD) based algorithm for suppressing low-frequency artifacts and additive high-frequency noises. Based upon mode center frequency criterion, the proposed method first constructs a candidate EGG feature signal for determination of glottal closure and opening instants. In the second stage, the candidate glottal instants are determined by detecting the positive and negative zerocrossings in normalized candidate EGG feature signal, respectively. Finally, an autocorrelation features based postprocessing algorithm is presented to reject non-glottal instants from the non-speech production segments. The accuracy and robustness of the method is tested using noise-free and noisy EGG signals. Evaluation results show that the proposed method achieves an average overall accuracy (OA) of 95.06%, identification rate (IR) of 95.34%, missed rate (MR) of 3.60% and false alarm rate (FAR) of 0.06% with average absolute identification error of 0.71 0.66 ms for a SNR of 15 dB. Results demonstrate that the proposed method significantly outperforms the other existing methods under both noise-free and noisy EGG signals.

  4. In-line phase-contrast stereoscopic X-ray imaging for radiological purposes: An initial experimental study

    NASA Astrophysics Data System (ADS)

    Siegbahn, E. A.; Coan, P.; Zhou, S.-A.; Bravin, A.; Brahme, A.

    2011-02-01

    We report results from a pilot study in which the in-line propagation-based phase-contrast imaging technique is combined with the stereoscopic method. Two phantoms were imaged at several sample-detector distances using monochromatic, 30 keV, X-rays. High contrast- and spatial-resolution phase-contrast stereoscopic pairs of X-ray images were constructed using the anaglyph approach and a vivid stereoscopic effect was demonstrated. On the other hand, images of the same phantoms obtained with a shorter sample-to-detector distance, but otherwise the same experimental conditions (i.e. the same X-ray energy and absorbed radiation dose), corresponding to the conventional attenuation-based imaging mode, hardly revealed stereoscopic effects because of the lower image contrast produced. These results have confirmed our hypothesis that stereoscopic X-ray images of samples with objects composed of low-atomic-number elements are considerably improved if phase-contrast imaging is used. It is our belief that the high-resolution phase-contrast stereoscopic method will be a valuable new medical imaging tool for radiologists and that it will be of help to enhance the diagnostic capability in the examination of patients in future clinical practice, even though further efforts will be needed to optimize the system performance.

  5. Designing stereoscopic information visualization for 3D-TV: What can we can learn from S3D gaming?

    NASA Astrophysics Data System (ADS)

    Schild, Jonas; Masuch, Maic

    2012-03-01

    This paper explores graphical design and spatial alignment of visual information and graphical elements into stereoscopically filmed content, e.g. captions, subtitles, and especially more complex elements in 3D-TV productions. The method used is a descriptive analysis of existing computer- and video games that have been adapted for stereoscopic display using semi-automatic rendering techniques (e.g. Nvidia 3D Vision) or games which have been specifically designed for stereoscopic vision. Digital games often feature compelling visual interfaces that combine high usability with creative visual design. We explore selected examples of game interfaces in stereoscopic vision regarding their stereoscopic characteristics, how they draw attention, how we judge effect and comfort and where the interfaces fail. As a result, we propose a list of five aspects which should be considered when designing stereoscopic visual information: explicit information, implicit information, spatial reference, drawing attention, and vertical alignment. We discuss possible consequences, opportunities and challenges for integrating visual information elements into 3D-TV content. This work shall further help to improve current editing systems and identifies a need for future editing systems for 3DTV, e.g., live editing and real-time alignment of visual information into 3D footage.

  6. An MR-compatible stereoscopic in-room 3D display for MR-guided interventions.

    PubMed

    Brunner, Alexander; Groebner, Jens; Umathum, Reiner; Maier, Florian; Semmler, Wolfhard; Bock, Michael

    2014-08-01

    A commercial three-dimensional (3D) monitor was modified for use inside the scanner room to provide stereoscopic real-time visualization during magnetic resonance (MR)-guided interventions, and tested in a catheter-tracking phantom experiment at 1.5 T. Brightness, uniformity, radio frequency (RF) emissions and MR image interferences were measured. Due to modifications, the center luminance of the 3D monitor was reduced by 14%, and the addition of a Faraday shield further reduced the remaining luminance by 31%. RF emissions could be effectively shielded; only a minor signal-to-noise ratio (SNR) decrease of 4.6% was observed during imaging. During the tracking experiment, the 3D orientation of the catheter and vessel structures in the phantom could be visualized stereoscopically.

  7. Quasi-stereoscopic imaging of the solar X-ray corona

    NASA Technical Reports Server (NTRS)

    Batchelor, David

    1994-01-01

    The first published three-dimensional images of the solar X-ray corona obtained by means of solar rotational parallax, are presented in stereographic form. Image pairs approximately 12 hours apart during times of stable coronal conditions were selected from the digitized images obtained with the Skylab X-ray Spectrographic Telescope. The image resolution limit is approximately 10 arc sec. Many coronal structures not visible in the separate images are clearly observed when the image pairs are viewed stereoscopically. This method gives a preview of the potential resources for solar research and forecasting of solar-geomagnetic interactions that could be provided by stereoscopic observations of the Sun using a small group of spacecraft. The method is also applicable to other X-ray, ultraviolet, or other wavebands in which the corona has extended, transparent structure.

  8. Electrothermal MEMS parallel plate rotation for single-imager stereoscopic endoscopes.

    PubMed

    Jang, Kyung-Won; Yang, Sung-Pyo; Baek, Seung-Hwan; Lee, Min-Suk; Park, Hyeon-Cheol; Seo, Yeong-Hyeon; Kim, Min H; Jeong, Ki-Hun

    2016-05-02

    This work reports electrothermal MEMS parallel plate-rotation (PPR) for a single-imager based stereoscopic endoscope. A thin optical plate was directly connected to an electrothermal MEMS microactuator with bimorph structures of thin silicon and aluminum layers. The fabricated MEMS PPR device precisely rotates an transparent optical plate up to 37° prior to an endoscopic camera and creates the binocular disparities, comparable to those from binocular cameras with a baseline distance over 100 μm. The anaglyph 3D images and disparity maps were successfully achieved by extracting the local binocular disparities from two optical images captured at the relative positions. The physical volume of MEMS PPR is well fit in 3.4 mm x 3.3 mm x 1 mm. This method provides a new direction for compact stereoscopic 3D endoscopic imaging systems.

  9. Optimizing visual comfort for stereoscopic 3D display based on color-plus-depth signals.

    PubMed

    Shao, Feng; Jiang, Qiuping; Fu, Randi; Yu, Mei; Jiang, Gangyi

    2016-05-30

    Visual comfort is a long-facing problem in stereoscopic 3D (S3D) display. In this paper, targeting to produce S3D content based on color-plus-depth signals, a general framework for depth mapping to optimize visual comfort for S3D display is proposed. The main motivation of this work is to remap the depth range of color-plus-depth signals to a new depth range that is suitable to comfortable S3D display. Towards this end, we first remap the depth range globally based on the adjusted zero disparity plane, and then present a two-stage global and local depth optimization solution to solve the visual comfort problem. The remapped depth map is used to generate the S3D output. We demonstrate the power of our approach on perceptually uncomfortable and comfortable stereoscopic images.

  10. Development of single-channel stereoscopic video imaging modality for real-time retinal imaging

    NASA Astrophysics Data System (ADS)

    Radfar, Edalat; Park, Jihoon; Lee, Sangyeob; Ha, Myungjin; Yu, Sungkon; Jang, Seulki; Jung, Byungjo

    2016-03-01

    Stereoscopic retinal image can effectively help doctors. Most of stereo imaging surgical microscopes are based on dual optical channels and benefit from dual cameras in which left and right cameras capture corresponding left and right eye views. This study developed a single-channel stereoscopic retinal imaging modality based on a transparent rotating deflector (TRD). Two different viewing angles are generated by imaging through the TRD which is mounted on a motor synchronized with a camera and is placed in single optical channel. Because of the function of objective lens in the imaging modality which generate stereo-image from an object at its focal point, and according to eye structure, the optical set up of the imaging modality can compatible for retinal imaging when the cornea and eye lens are engaged in objective lens.

  11. Phase-only stereoscopic hologram calculation based on Gerchberg-Saxton iterative algorithm

    NASA Astrophysics Data System (ADS)

    Xia, Xinyi; Xia, Jun

    2016-09-01

    A phase-only computer-generated holography (CGH) calculation method for stereoscopic holography is proposed in this paper. The two-dimensional (2D) perspective projection views of the three-dimensional (3D) object are generated by the computer graphics rendering techniques. Based on these views, a phase-only hologram is calculated by using the Gerchberg-Saxton (GS) iterative algorithm. Comparing with the non-iterative algorithm in the conventional stereoscopic holography, the proposed method improves the holographic image quality, especially for the phase-only hologram encoded from the complex distribution. Both simulation and optical experiment results demonstrate that our proposed method can give higher quality reconstruction comparing with the traditional method. Project supported by the National Basic Research Program of China (Grant No. 2013CB328803) and the National High Technology Research and Development Program of China (Grant Nos. 2013AA013904 and 2015AA016301).

  12. Self-calibration performance in stereoscopic PIV acquired in a transonic wind tunnel

    SciTech Connect

    Beresh, Steven J.; Wagner, Justin L.; Smith, Barton L.

    2016-03-16

    Three stereoscopic PIV experiments have been examined to test the effectiveness of self-calibration under varied circumstances. Furthermore, we our measurements taken in a streamwise plane yielded a robust self-calibration that returned common results regardless of the specific calibration procedure, but measurements in the crossplane exhibited substantial velocity bias errors whose nature was sensitive to the particulars of the self-calibration approach. Self-calibration is complicated by thick laser sheets and large stereoscopic camera angles and further exacerbated by small particle image diameters and high particle seeding density. In spite of the different answers obtained by varied self-calibrations, each implementation locked onto an apparently valid solution with small residual disparity and converged adjustment of the calibration plane. Thus, the convergence of self-calibration on a solution with small disparity is not sufficient to indicate negligible velocity error due to the stereo calibration.

  13. Self-calibration performance in stereoscopic PIV acquired in a transonic wind tunnel

    DOE PAGES

    Beresh, Steven J.; Wagner, Justin L.; Smith, Barton L.

    2016-03-16

    Three stereoscopic PIV experiments have been examined to test the effectiveness of self-calibration under varied circumstances. Furthermore, we our measurements taken in a streamwise plane yielded a robust self-calibration that returned common results regardless of the specific calibration procedure, but measurements in the crossplane exhibited substantial velocity bias errors whose nature was sensitive to the particulars of the self-calibration approach. Self-calibration is complicated by thick laser sheets and large stereoscopic camera angles and further exacerbated by small particle image diameters and high particle seeding density. In spite of the different answers obtained by varied self-calibrations, each implementation locked onto anmore » apparently valid solution with small residual disparity and converged adjustment of the calibration plane. Thus, the convergence of self-calibration on a solution with small disparity is not sufficient to indicate negligible velocity error due to the stereo calibration.« less

  14. Stereoscopic vision-based robotic manipulator extraction method for enhanced soft tissue reconstruction.

    PubMed

    Kowalczuk, Jędrzej; Psota, Eric; Pérez, Lance C

    2013-01-01

    The availability of digital stereoscopic video feedback on surgical robotic platforms allows for a variety of enhancements through the application of computer vision. Several of these enhancements, such as augmented reality and semi-automated surgery, benefit significantly from identification of the robotic manipulators within the field of view. A method is presented for the extraction of robotic manipulators from stereoscopic views of the operating field that uses a combination of marker tracking, inverse kinematics, and computer rendering. This method is shown to accurately identify the locations of the manipulators within the views. It is further demonstrated that this method can be used to enhance 3D reconstruction of the operating field and produce augmented views.

  15. An optimized web-based approach for collaborative stereoscopic medical visualization

    PubMed Central

    Kaspar, Mathias; Parsad, Nigel M; Silverstein, Jonathan C

    2013-01-01

    Objective Medical visualization tools have traditionally been constrained to tethered imaging workstations or proprietary client viewers, typically part of hospital radiology systems. To improve accessibility to real-time, remote, interactive, stereoscopic visualization and to enable collaboration among multiple viewing locations, we developed an open source approach requiring only a standard web browser with no added client-side software. Materials and Methods Our collaborative, web-based, stereoscopic, visualization system, CoWebViz, has been used successfully for the past 2 years at the University of Chicago to teach immersive virtual anatomy classes. It is a server application that streams server-side visualization applications to client front-ends, comprised solely of a standard web browser with no added software. Results We describe optimization considerations, usability, and performance results, which make CoWebViz practical for broad clinical use. We clarify technical advances including: enhanced threaded architecture, optimized visualization distribution algorithms, a wide range of supported stereoscopic presentation technologies, and the salient theoretical and empirical network parameters that affect our web-based visualization approach. Discussion The implementations demonstrate usability and performance benefits of a simple web-based approach for complex clinical visualization scenarios. Using this approach overcomes technical challenges that require third-party web browser plug-ins, resulting in the most lightweight client. Conclusions Compared to special software and hardware deployments, unmodified web browsers enhance remote user accessibility to interactive medical visualization. Whereas local hardware and software deployments may provide better interactivity than remote applications, our implementation demonstrates that a simplified, stable, client approach using standard web browsers is sufficient for high quality three

  16. Effects of Stereoscopic 3D Digital Radar Displays on Air Traffic Controller Performance

    DTIC Science & Technology

    2013-03-01

    of air traffic control. As early as 1948, papers were written examining the potential for 3D displays of radar images (Parker and Wallis , 1948...stereoscopic viewing for the purpose of air traffic control potential has been met with mixed results (Parker & Wallis , 1948; McIntire et al, 2012). In...visual, audio and written cues to gather needed information upon which to make decisions. In fact, Hopkin claims that forgetting information may be

  17. What every surgeon wants: practical aspects on the use of stereoscopic applications in operative theatres

    NASA Astrophysics Data System (ADS)

    Ilgner, Justus; Biedron, Slavomir; Westhofen, Martin

    2010-02-01

    Introduction: Many operative specialties rely on the use of microscopes and endoscopes for visualizing operative fields in minimally invasive or microsurgical interventions. Conventional optical devices present relevant details only to the surgeon or one assisting professional. Advances in information technology have propagated stereoscopic visual information to all operative theatre personnel in real time, which, in turn, adds to the load of complex technical devices to be handled and maintained in operative theatres. Material and methods: In the last six years, we have been using conventional (SD, 720 x 576 pixels) and high definition (1280 x 720 pixels) stereoscopic video cameras attached to conventional operative microscopes either in parallel to direct visualization of the operative field or as all-digital processing of the operative image for the surgeon including all other staff. Aspects included the type of display used, image quality, time delay due to image processing, visual comfort, time consumption in set-up, ease of use as well as robustness of the system. Results: General acceptance of stereoscopic display technology is high as all staff members are able to share the same visual information. The use of stereo cameras in parallel to direct visualization or as only visualization device mostly depended on image quality and personal preference of the surgeon. Predominant general factors are robustness, ease of use and additional time consumption imposed by setup and handling. Visual comfort was noted as moderately important as there was wide variability between staff members. Type of display used and post-processing issues were regarded less important. Time delay induced by the video chain was negligible. Conclusion: The additional information given by stereoscopic video processing in real time outweighs the extra effort for handling and maintenance. However, further integration with existing technology and with the general workflow enhances acceptance

  18. An optimized web-based approach for collaborative stereoscopic medical visualization.

    PubMed

    Kaspar, Mathias; Parsad, Nigel M; Silverstein, Jonathan C

    2013-05-01

    Medical visualization tools have traditionally been constrained to tethered imaging workstations or proprietary client viewers, typically part of hospital radiology systems. To improve accessibility to real-time, remote, interactive, stereoscopic visualization and to enable collaboration among multiple viewing locations, we developed an open source approach requiring only a standard web browser with no added client-side software. Our collaborative, web-based, stereoscopic, visualization system, CoWebViz, has been used successfully for the past 2 years at the University of Chicago to teach immersive virtual anatomy classes. It is a server application that streams server-side visualization applications to client front-ends, comprised solely of a standard web browser with no added software. We describe optimization considerations, usability, and performance results, which make CoWebViz practical for broad clinical use. We clarify technical advances including: enhanced threaded architecture, optimized visualization distribution algorithms, a wide range of supported stereoscopic presentation technologies, and the salient theoretical and empirical network parameters that affect our web-based visualization approach. The implementations demonstrate usability and performance benefits of a simple web-based approach for complex clinical visualization scenarios. Using this approach overcomes technical challenges that require third-party web browser plug-ins, resulting in the most lightweight client. Compared to special software and hardware deployments, unmodified web browsers enhance remote user accessibility to interactive medical visualization. Whereas local hardware and software deployments may provide better interactivity than remote applications, our implementation demonstrates that a simplified, stable, client approach using standard web browsers is sufficient for high quality three-dimensional, stereoscopic, collaborative and interactive visualization.

  19. Real-time arbitrary view synthesis method for ultra-HD auto-stereoscopic display

    NASA Astrophysics Data System (ADS)

    Cai, Yuanfa; Sang, Xinzhu; Duo, Chen; Zhao, Tianqi; Fan, Xin; Guo, Nan; Yu, Xunbo; Yan, Binbin

    2013-08-01

    An arbitrary view synthesis method from 2D-Plus-Depth image for real-time auto-stereoscopic display is presented. Traditional methods use depth image based rendering (DIBR) technology, which is a process of synthesizing "virtual" views of a scene from still or moving images and associated per-pixel depth information. All the virtual view images are generated and then the ultimate stereo-image is synthesized. DIBR can greatly decrease the number of reference images and is flexible and efficient as the depth images are used. However it causes some problems such as the appearance of holes in the rendered image, and the occurrence of depth discontinuity on the surface of the object at virtual image plane. Here, reversed disparity shift pixel rendering is used to generate the stereo-image directly, and the target image won't generate holes. To avoid duplication of calculation and also to be able to match with any specific three-dimensional display, a selecting table is designed to pick up appropriate virtual viewpoints for auto-stereoscopic display. According to the selecting table, only sub-pixels of the appropriate virtual viewpoints are calculated, so calculation amount is independent of the number of virtual viewpoints. In addition, 3D image warping technology is used to translate depth information to parallax between virtual viewpoints and parallax, and the viewer can adjust the zero-parallax-setting-plane (ZPS) and change parallax conveniently to suit his/her personal preferences. The proposed method is implemented with OPENGL and demonstrated on a laptop computer with a 2.3 GHz Intel Core i5 CPU and NVIDA GeForce GT540m GPU. We got a frame rate 30 frames per second with 4096×2340 video. High synthesis efficiency and good stereoscopic sense can be obtained. The presented method can meet the requirements of real-time ultra-HD super multi-view auto-stereoscopic display.

  20. Identification of depth information with stereoscopic mammography using different display methods

    NASA Astrophysics Data System (ADS)

    Morikawa, Takamitsu; Kodera, Yoshie

    2013-03-01

    Stereoscopy in radiography was widely used in the late 80's because it could be used for capturing complex structures in the human body, thus proving beneficial for diagnosis and screening. When radiologists observed the images stereoscopically, radiologists usually needed the training of their eyes in order to perceive the stereoscopic effect. However, with the development of three-dimensional (3D) monitors and their use in the medical field, only a visual inspection is no longer required in the medical field. The question then arises as to whether there is any difference in recognizing depth information when using conventional methods and that when using a 3D monitor. We constructed a phantom and evaluated the difference in capacity to identify the depth information between the two methods. The phantom consists of acryl steps and 3mm diameter acryl pillars on the top and bottom of each step. Seven observers viewed these images stereoscopically using the two display methods and were asked to judge the direction of the pillar that was on the top. We compared these judged direction with the direction of the real pillar arranged on the top, and calculated the percentage of correct answerers (PCA). The results showed that PCA obtained using the 3D monitor method was higher PCA by about 5% than that obtained using the naked-eye method. This indicated that people could view images stereoscopically more precisely using the 3D monitor method than when using with conventional methods, like the crossed or parallel eye viewing. We were able to estimate the difference in capacity to identify the depth information between the two display methods.

  1. Occurrence of deoxynivalenol in wheat flour, instant noodle and biscuits commercialised in Brazil.

    PubMed

    Almeida, Adriana Palma de; Lamardo, Leda Conceição Antonia; Shundo, Luzia; Silva, Simone Alves da; Navas, Sandra Aparecida; Alaburda, Janete; Ruvieri, Valter; Sabino, Myrna

    2016-12-01

    A total of 134 samples, consisting of 58 wheat flour, 40 instant noodle and 36 biscuits, were analysed for the presence of deoxynivalenol (DON). The samples were obtained from retail markets of the city of São Paulo during the period 2010-2014. DON was determined by high performance liquid chromatography with ultraviolet detection and immunoaffinity sample clean-up. Method validation followed international guidelines. The LOD and LOQ were 60 and 200 µg kg(-1), respectively, considering the three different types of samples analysed. The lowest recovery found in this study was 91.8% with RSD 4.5% for instant noodles. DON was detected in 91.4%, 97.5% and 97.2% of samples wheat flour, instant noodles and biscuits, respectively, resulting in a total of 94.8% with levels ranging from LOD to 1720.0 µg kg(-1).

  2. Instant release fraction corrosion studies of commercial UO2 BWR spent nuclear fuel

    NASA Astrophysics Data System (ADS)

    Martínez-Torrents, Albert; Serrano-Purroy, Daniel; Sureda, Rosa; Casas, Ignasi; de Pablo, Joan

    2017-05-01

    The instant release fraction of a spent nuclear fuel is a matter of concern in the performance assessment of a deep geological repository since it increases the radiological risk. Corrosion studies of two different spent nuclear fuels were performed using bicarbonate water under oxidizing conditions to study their instant release fraction. From each fuel, cladded segments and powder samples obtained at different radial positions were used. The results were normalised using the specific surface area to permit a comparison between fuels and samples. Different radionuclide dissolution patterns were studied in terms of water contact availability and radial distribution in the spent nuclear fuel. The relationship between the results of this work and morphological parameters like the grain size or irradiation parameters such as the burn-up or the linear power density was studied in order to increase the understanding of the instant release fraction formation.

  3. Macroscopic three-dimensional particle location using stereoscopic imaging and astigmatic aberrations.

    PubMed

    Fuchs, Thomas; Hain, Rainer; Kähler, Christian J

    2014-12-15

    This Letter presents a stereoscopic imaging concept for measuring the locations of particles in three-dimensional space. The method is derived from astigmatism particle tracking velocimetry (APTV), a powerful technique that is capable of determining 3D particle locations with a single camera. APTV locates particle xy coordinates with high accuracy, while the particle z coordinate has a larger location uncertainty. This is not a problem for 3D2C (i.e., three dimensions, two velocity components) measurements, but for highly three-dimensional flows, it is desirable to measure three velocity components with similar accuracy. The stereoscopic APTV approach discussed in this report has this capability. The technique employs APTV for giving an initial estimate of the particle locations. With this information, corresponding particle images on both sensors of the stereoscopic imaging system are matched. Particle locations are then determined by mapping the two particle image sensor locations to physical space. The measurement error of stereo APTV, determined by acquiring images of 1-μm DEHS particles in a 40 mm×40 mm×20 mm measurement volume in air at Δxyz→0 between two frames, is less than 0.012 mm for xy and 0.025 mm for z. This error analysis proves the excellent suitability of stereo APTV for the measurement of three-dimensional flows in macroscopic domains.

  4. Monoscopic versus stereoscopic photography in screening for clinically significant macular edema.

    PubMed

    Welty, Christopher J; Agarwal, Anita; Merin, Lawrence M; Chomsky, Amy

    2006-01-01

    The purpose of the study was to determine whether monoscopic photography could serve as an accurate tool when used to screen for clinically significant macular edema. In a masked randomized fashion, two readers evaluated monoscopic and stereoscopic retinal photographs of 100 eyes. The photographs were evaluated first individually for probable clinically significant macular edema based on the Early Treatment Diabetic Retinopathy Study criteria and then as stereoscopic pairs. Graders were evaluated for sensitivity and specificity individually and in combination. Individually, reader one had a sensitivity of 0.93 and a specificity of 0.77, and reader two had a sensitivity of 0.88 and a specificity of 0.94. In combination, the readers had a sensitivity of 0.91 and a specificity of 0.86. They correlated on 0.76 of the stereoscopic readings and 0.92 of the monoscopic readings. These results indicate that the use of monoscopic retinal photography may be an accurate screening tool for clinically significant macular edema.

  5. Web GIS in practice VII: stereoscopic 3-D solutions for online maps and virtual globes.

    PubMed

    Boulos, Maged N Kamel; Robinson, Larry R

    2009-10-22

    Because our pupils are about 6.5 cm apart, each eye views a scene from a different angle and sends a unique image to the visual cortex, which then merges the images from both eyes into a single picture. The slight difference between the right and left images allows the brain to properly perceive the 'third dimension' or depth in a scene (stereopsis). However, when a person views a conventional 2-D (two-dimensional) image representation of a 3-D (three-dimensional) scene on a conventional computer screen, each eye receives essentially the same information. Depth in such cases can only be approximately inferred from visual clues in the image, such as perspective, as only one image is offered to both eyes. The goal of stereoscopic 3-D displays is to project a slightly different image into each eye to achieve a much truer and realistic perception of depth, of different scene planes, and of object relief. This paper presents a brief review of a number of stereoscopic 3-D hardware and software solutions for creating and displaying online maps and virtual globes (such as Google Earth) in "true 3D", with costs ranging from almost free to multi-thousand pounds sterling. A practical account is also given of the experience of the USGS BRD UMESC (United States Geological Survey's Biological Resources Division, Upper Midwest Environmental Sciences Center) in setting up a low-cost, full-colour stereoscopic 3-D system.

  6. Stereoscopic representation of the breast from two mammographic view with external markers

    NASA Astrophysics Data System (ADS)

    Kallergi, Maria; Manohar, Anand

    2003-05-01

    A new breast imaging technique has been develoepd and tested for the stereoscopic representation of the breast. The method uses markers at specific locations on the breast surface and standard mammographic projections and was tested with an anthropomorphic phantom containing five mass-like objects at locations determined by a CT scan. The phantom was imaged with a GE Senographe 2000D digital system with and without the markers. The algorithm's modules included: 1) Breast area segmentation; 2) Pectoral muscle segmentation; 3) Registration and alignment of the mammographic projections based on selected reference points; 4) Breast volume estimation basdd on volume conservation principle during compression and shape definition using surface points; 5) 3D lesion(s) localization and representation. An interactive, ILD-based, graphical interface was also developed for the stereoscopic display of the breast. The reconstruction algorithm assumed that the breast shrinks and stretches uniformly when compression is applied and removed. The relative movement of the markers after compression allowed more accurate estimation of the shrinking and stretching of the surface offering a relatively simple and practical way to improve volume estimation and surface reconstruction. Such stereoscopic representation of the breast and associated findings may improve radiological interpretation and physical examinations for breast cancer diagnosis.

  7. Using Saliency-Weighted Disparity Statistics for Objective Visual Comfort Assessment of Stereoscopic Images

    NASA Astrophysics Data System (ADS)

    Zhang, Wenlan; Luo, Ting; Jiang, Gangyi; Jiang, Qiuping; Ying, Hongwei; Lu, Jing

    2016-06-01

    Visual comfort assessment (VCA) for stereoscopic images is a particularly significant yet challenging task in 3D quality of experience research field. Although the subjective assessment given by human observers is known as the most reliable way to evaluate the experienced visual discomfort, it is time-consuming and non-systematic. Therefore, it is of great importance to develop objective VCA approaches that can faithfully predict the degree of visual discomfort as human beings do. In this paper, a novel two-stage objective VCA framework is proposed. The main contribution of this study is that the important visual attention mechanism of human visual system is incorporated for visual comfort-aware feature extraction. Specifically, in the first stage, we first construct an adaptive 3D visual saliency detection model to derive saliency map of a stereoscopic image, and then a set of saliency-weighted disparity statistics are computed and combined to form a single feature vector to represent a stereoscopic image in terms of visual comfort. In the second stage, a high dimensional feature vector is fused into a single visual comfort score by performing random forest algorithm. Experimental results on two benchmark databases confirm the superior performance of the proposed approach.

  8. Field trials of stereoscopic video with an underwater remotely operated vehicle

    NASA Astrophysics Data System (ADS)

    Woods, Andrew J.; Docherty, Tom; Koch, Rolf

    1994-04-01

    We have developed a flicker-free stereoscopic video system which uses commercial television components. This system has been installed on an underwater remotely operated vehicle (ROV) that is used for service and inspection tasks at a gas production platform 130 km off the North-West coast of Western Australia. We report the results of field and laboratory time trials of remote manipulation tasks and also the general experience gained in the field operation of the system. Stereoscopic video provides the operator with an intuitive sense of the depth relationships of the work site. Operators report that this reduces frustration and mental effort as well as giving them confidence in their actions. Some of the other advantages that we have observed include the increased ability to see through suspended matter (fine particles) in the water. The system is most useful in manipulative tasks but also useful for general `flying' of the ROV making navigation through the platform easier. Our results indicate that stereoscopic video will be a valuable tool in the operation of remotely operated vehicles in the underwater environment.

  9. Toward a 3D video format for auto-stereoscopic displays

    NASA Astrophysics Data System (ADS)

    Vetro, Anthony; Yea, Sehoon; Smolic, Aljoscha

    2008-08-01

    There has been increased momentum recently in the production of 3D content for cinema applications; for the most part, this has been limited to stereo content. There are also a variety of display technologies on the market that support 3DTV, each offering a different viewing experience and having different input requirements. More specifically, stereoscopic displays support stereo content and require glasses, while auto-stereoscopic displays avoid the need for glasses by rendering view-dependent stereo pairs for a multitude of viewing angles. To realize high quality auto-stereoscopic displays, multiple views of the video must either be provided as input to the display, or these views must be created locally at the display. The former approach has difficulties in that the production environment is typically limited to stereo, and transmission bandwidth for a large number of views is not likely to be available. This paper discusses an emerging 3D data format that enables the latter approach to be realized. A new framework for efficiently representing a 3D scene and enabling the reconstruction of an arbitrarily large number of views prior to rendering is introduced. Several design challenges are also highlighted through experimental results.

  10. Model-based 3-D scene analysis from stereoscopic image sequences

    NASA Astrophysics Data System (ADS)

    Koch, Reinhard

    A vision-based 3-D scene analysis system is described that is capable to model complex real-world scences like buildings automatically from stereoscopic image pairs. Input to the system is a sequence of stereoscopic images taken with two standard CCD Cameras and TV lenses. The relative orientation of both cameras to each other is known by calibration. The camera pair is then moved throughout the scene and a long sequence of closely spaced views is recorded. Each of the stereoscopic image pairs is rectified and a dense map of 3-D surface points is obtained by area correlation, object segmentation, interpolation, and triangulation. 3-D camera motion relative to the scene coordinate system is tracked directly from the image sequence which allows to fuse 3-D surface measurements from different view points into a consistent 3-D model scence. The surface geometry of each scene object is approximated by a triangular surface mesh which stores the surface texture in a texture map. From the textured 3-D models, realistic looking image sequences from arbitrary view points can be synthesized using computer graphics.

  11. Laparoscopic stereoscopic augmented reality: toward a clinically viable electromagnetic tracking solution.

    PubMed

    Liu, Xinyang; Kang, Sukryool; Plishker, William; Zaki, George; Kane, Timothy D; Shekhar, Raj

    2016-10-01

    The purpose of this work was to develop a clinically viable laparoscopic augmented reality (AR) system employing stereoscopic (3-D) vision, laparoscopic ultrasound (LUS), and electromagnetic (EM) tracking to achieve image registration. We investigated clinically feasible solutions to mount the EM sensors on the 3-D laparoscope and the LUS probe. This led to a solution of integrating an externally attached EM sensor near the imaging tip of the LUS probe, only slightly increasing the overall diameter of the probe. Likewise, a solution for mounting an EM sensor on the handle of the 3-D laparoscope was proposed. The spatial image-to-video registration accuracy of the AR system was measured to be [Formula: see text] and [Formula: see text] for the left- and right-eye channels, respectively. The AR system contributed 58-ms latency to stereoscopic visualization. We further performed an animal experiment to demonstrate the use of the system as a visualization approach for laparoscopic procedures. In conclusion, we have developed an integrated, compact, and EM tracking-based stereoscopic AR visualization system, which has the potential for clinical use. The system has been demonstrated to achieve clinically acceptable accuracy and latency. This work is a critical step toward clinical translation of AR visualization for laparoscopic procedures.

  12. Evaluation of monoscopic and stereoscopic displays for visual-spatial tasks in medical contexts.

    PubMed

    Martinez Escobar, Marisol; Junke, Bethany; Holub, Joseph; Hisley, Kenneth; Eliot, David; Winer, Eliot

    2015-06-01

    In the medical field, digital images are present in diagnosis, pre-operative planning, minimally invasive surgery, instruction, and training. The use of medical digital imaging has afforded new ways to interact with a patient, such as seeing fine details inside a body. This increased usage also raises many basic research questions on human perception and performance when utilizing these images. The work presented here attempts to answer the question: How would adding the stereopsis depth cue affect relative position tasks in a medical context compared to a monoscopic view? By designing and conducting a study to isolate the benefits between monoscopic 3D and stereoscopic 3D displays in a relative position task, the following hypothesis was tested: stereoscopic 3D displays are beneficial over monoscopic 3D displays for relative position judgment tasks in a medical visualization setting. 44 medical students completed a series of relative position judgments tasks. The results show that stereoscopic condition yielded a higher score than the monoscopic condition with regard to the hypothesis.

  13. Drilling into the functional significance of stereopsis: the impact of stereoscopic information on surgical performance.

    PubMed

    Al-Saud, Loulwa M; Mushtaq, Faisal; Mirghani, Isra'a; Balkhoyor, Ahmed; Keeling, Andrew; Manogue, Michael; Mon-Williams, Mark A

    2017-07-01

    One suggested advantage of human binocular vision is the facilitation of sophisticated motor control behaviours via stereopsis - but little empirical evidence exists to support this suggestion. We examined the functional significance of stereopsis by exploring whether stereopsis is used to perform a highly skilled real-world motor task essential for the occupational practice of dentistry. We used a high fidelity virtual reality simulator to study how dentists' performance is affected by the removal of horizontal retinal image disparities under direct and indirect (mirror) observation. Thirteen qualified dentists performed a total of four different dental tasks under non-stereoscopic and stereoscopic vision conditions, with two levels of task complexity (direct and indirect observation) using a virtual reality dental simulator. Depth related errors were significantly higher under non-stereoscopic viewing but lateral errors did not differ between conditions. Indirect observation led to participants drilling less of the target area compared to direct viewing, but this did not interact with the stereopsis manipulation. The data confirm that dental practitioners use stereopsis and its presence results in improved dental performance. It remains to be determined whether individuals with stereo-deficits can compensate adequately. Nevertheless, these findings suggest an important role for stereopsis within at least one occupation and justify the design of simulators with 3D displays. © 2017 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.

  14. Web GIS in practice VII: stereoscopic 3-D solutions for online maps and virtual globes

    PubMed Central

    Boulos, Maged N Kamel; Robinson, Larry R

    2009-01-01

    Because our pupils are about 6.5 cm apart, each eye views a scene from a different angle and sends a unique image to the visual cortex, which then merges the images from both eyes into a single picture. The slight difference between the right and left images allows the brain to properly perceive the 'third dimension' or depth in a scene (stereopsis). However, when a person views a conventional 2-D (two-dimensional) image representation of a 3-D (three-dimensional) scene on a conventional computer screen, each eye receives essentially the same information. Depth in such cases can only be approximately inferred from visual clues in the image, such as perspective, as only one image is offered to both eyes. The goal of stereoscopic 3-D displays is to project a slightly different image into each eye to achieve a much truer and realistic perception of depth, of different scene planes, and of object relief. This paper presents a brief review of a number of stereoscopic 3-D hardware and software solutions for creating and displaying online maps and virtual globes (such as Google Earth) in "true 3D", with costs ranging from almost free to multi-thousand pounds sterling. A practical account is also given of the experience of the USGS BRD UMESC (United States Geological Survey's Biological Resources Division, Upper Midwest Environmental Sciences Center) in setting up a low-cost, full-colour stereoscopic 3-D system. PMID:19849837

  15. Effect of accommodation training by stereoscopic movie presentation on myopic youth

    NASA Astrophysics Data System (ADS)

    Sugiura, A.; Takada, H.; Yamamoto, T.; Miyao, M.

    2010-02-01

    The abnormal contraction of ciliary muscles due to the performance of a near visual task for several hours causes various vision problems such as asthenopia and visual loss. However, these problems can be resolved by activating the muscles by alternately repeating negative and positive accommodation. In this study, we have verified the effect of accommodation training that uses the strategy of presenting a stereoscopic movie to myopic youth and measuring the uncorrected distant visual acuity, spherical diopter (SPH), and subjective index of asthenopia obtained using a visual analog scale (VAS). Stereoscopic movies are prepared by using the POWER 3D method (Olympus Visual Communications Co., Ltd.), which reduces the inconsistency between the experienced and the actual senses. Thirty two myopic students aged 20 +/- 1 years (16 males and 16 females) were chosen as the subjects. One group performed the accommodation training for 6 min, and the other group underwent a near visual task during the same period as the control group. We concluded the following from each item of verification: (a) The accommodation training using a stereoscopic movie had temporarily improved visual acuity. (b) This training led to a decrease in asthenopia. (c) The training improved the near-point accommodation function.

  16. A dataset of stereoscopic images and ground-truth disparity mimicking human fixations in peripersonal space.

    PubMed

    Canessa, Andrea; Gibaldi, Agostino; Chessa, Manuela; Fato, Marco; Solari, Fabio; Sabatini, Silvio P

    2017-03-28

    Binocular stereopsis is the ability of a visual system, belonging to a live being or a machine, to interpret the different visual information deriving from two eyes/cameras for depth perception. From this perspective, the ground-truth information about three-dimensional visual space, which is hardly available, is an ideal tool both for evaluating human performance and for benchmarking machine vision algorithms. In the present work, we implemented a rendering methodology in which the camera pose mimics realistic eye pose for a fixating observer, thus including convergent eye geometry and cyclotorsion. The virtual environment we developed relies on highly accurate 3D virtual models, and its full controllability allows us to obtain the stereoscopic pairs together with the ground-truth depth and camera pose information. We thus created a stereoscopic dataset: GENUA PESTO-GENoa hUman Active fixation database: PEripersonal space STereoscopic images and grOund truth disparity. The dataset aims to provide a unified framework useful for a number of problems relevant to human and computer vision, from scene exploration and eye movement studies to 3D scene reconstruction.

  17. [Spectral study of the effects of glasses lenses' color depth on stereoscopic vision].

    PubMed

    Yan, Bing; Zhao, Zhan-Juan; Hu, Jin-Min; Li, Jing-Ping; Fan, Chun-Xia

    2008-01-01

    Glasses with zero focal-length lens and different shades of red, yellow and blue were studied in terms of absorbance by UV-Vis spectral absorption method. The effect of lens with different shades of the same color on stereoscopic vision was comparatively studied from the medical view. The study has shown that, for yellow and blue lens, there is no difference in the absorbance between the deep-color and light-color lens in UV; at 550 nm, the absorbance of deep-color lens is higher than that of light-color lens. Whereas, for red lens, the absorbance of light-color lens in UV is higher, and at 550 nm, still higher than that of deep-color. Those with light-color glasses of yellow or blue have much better stereoscopic vision than those with deep-color glasses, while the case is inversed as to those wearing red glasses. The conclusion can be drawn that the effect of lens with different shades on stereoscopic vision depends on the absorbance of lens at 550 nm, and the higher the absorbance, the stronger the effect.

  18. Learning Receptive Fields and Quality Lookups for Blind Quality Assessment of Stereoscopic Images.

    PubMed

    Shao, Feng; Lin, Weisi; Wang, Shanshan; Jiang, Gangyi; Yu, Mei; Dai, Qionghai

    2016-03-01

    Blind quality assessment of 3D images encounters more new challenges than its 2D counterparts. In this paper, we propose a blind quality assessment for stereoscopic images by learning the characteristics of receptive fields (RFs) from perspective of dictionary learning, and constructing quality lookups to replace human opinion scores without performance loss. The important feature of the proposed method is that we do not need a large set of samples of distorted stereoscopic images and the corresponding human opinion scores to learn a regression model. To be more specific, in the training phase, we learn local RFs (LRFs) and global RFs (GRFs) from the reference and distorted stereoscopic images, respectively, and construct their corresponding local quality lookups (LQLs) and global quality lookups (GQLs). In the testing phase, blind quality pooling can be easily achieved by searching optimal GRF and LRF indexes from the learnt LQLs and GQLs, and the quality score is obtained by combining the LRF and GRF indexes together. Experimental results on three publicly 3D image quality assessment databases demonstrate that in comparison with the existing methods, the devised algorithm achieves high consistent alignment with subjective assessment.

  19. Spatial visualization ability and laparoscopic skills in novice learners: evaluating stereoscopic versus monoscopic visualizations.

    PubMed

    Roach, Victoria A; Mistry, Manisha R; Wilson, Timothy D

    2014-01-01

    Elevated spatial visualization ability (Vz) is thought to influence surgical skill acquisition and performance. Current research suggests that stereo visualization technology and its association with skill performance may confer perceptual advantages. This is of particular interest in laparoscopic skill training, where stereo visualization may confer learning advantages to novices of variant Vz. This study explored laparoscopic skill performance scores in novices with variable spatial ability utilizing stereoscopic and traditional monoscopic visualization paradigms. Utilizing the McGill Inanimate System for Teaching and Evaluating Laparoscopic Skills (MISTELS) scoring protocol it was hypothesized that individuals with high spatial visualization ability (HVz) would achieve higher overall and individual MISTELS task scores as compared to low spatial visualization ability (LVz) counterparts. Further, we also hypothesized that a difference would exist between HVz and LVz individual scores based on the viewing modality employed. No significant difference was observed between HVz and LVz individuals for MISTELS tasks scores, overall or individually under both viewing modalities, despite higher average MISTELS scores for HVz individuals. The lack of difference between scores obtained under the stereo modality suggested that the additional depth that is conferred by the stereoscopic visualization may act to enhance performance for individuals with LVz, potentially equilibrating their performance with their HVz peers. Further experimentation is required to better ascertain the effects of stereo visualization in individuals of high and low Vz, though it appears stereoscopic visualizations could serve as a prosthetic to enhance skill performance.

  20. A dataset of stereoscopic images and ground-truth disparity mimicking human fixations in peripersonal space

    PubMed Central

    Canessa, Andrea; Gibaldi, Agostino; Chessa, Manuela; Fato, Marco; Solari, Fabio; Sabatini, Silvio P.

    2017-01-01

    Binocular stereopsis is the ability of a visual system, belonging to a live being or a machine, to interpret the different visual information deriving from two eyes/cameras for depth perception. From this perspective, the ground-truth information about three-dimensional visual space, which is hardly available, is an ideal tool both for evaluating human performance and for benchmarking machine vision algorithms. In the present work, we implemented a rendering methodology in which the camera pose mimics realistic eye pose for a fixating observer, thus including convergent eye geometry and cyclotorsion. The virtual environment we developed relies on highly accurate 3D virtual models, and its full controllability allows us to obtain the stereoscopic pairs together with the ground-truth depth and camera pose information. We thus created a stereoscopic dataset: GENUA PESTO—GENoa hUman Active fixation database: PEripersonal space STereoscopic images and grOund truth disparity. The dataset aims to provide a unified framework useful for a number of problems relevant to human and computer vision, from scene exploration and eye movement studies to 3D scene reconstruction. PMID:28350382

  1. Case study: the introduction of stereoscopic games on the Sony PlayStation 3

    NASA Astrophysics Data System (ADS)

    Bickerstaff, Ian

    2012-03-01

    A free stereoscopic firmware update on Sony Computer Entertainment's PlayStation® 3 console provides the potential to increase enormously the popularity of stereoscopic 3D in the home. For this to succeed though, a large selection of content has to become available that exploits 3D in the best way possible. In addition to the existing challenges found in creating 3D movies and television programmes, the stereography must compensate for the dynamic and unpredictable environments found in games. Automatically, the software must map the depth range of the scene into the display's comfort zone, while minimising depth compression. This paper presents a range of techniques developed to solve this problem and the challenge of creating twice as many images as the 2D version without excessively compromising the frame rate or image quality. At the time of writing, over 80 stereoscopic PlayStation 3 games have been released and notable titles are used as examples to illustrate how the techniques have been adapted for different game genres. Since the firmware's introduction in 2010, the industry has matured with a large number of developers now producing increasingly sophisticated 3D content. New technologies such as viewer head tracking and head-mounted displays should increase the appeal of 3D in the home still further.

  2. Why 3D Cameras are Not Popular: A Qualitative User Study on Stereoscopic Photography Acceptance

    NASA Astrophysics Data System (ADS)

    Hakala, Jussi; Westman, Stina; Salmimaa, Marja; Pölönen, Monika; Järvenpää, Toni; Häkkinen, Jukka

    2014-03-01

    Digital stereoscopic 3D cameras have entered the consumer market in recent years, but the acceptance of this novel technology has not yet been studied. The aim of this study was to identify the benefits and problems that novice users encounter in 3D photography by equipping five users with 3D cameras for a 4-week trial. We gathered data using a weekly questionnaire, an exit interview, and a stereoscopic disparity analysis of the 699 photographs taken during the trial. The results indicate that the participants took photographs at too-close distances, which caused excessive disparities. They learned to avoid the problem to some extent; the number of failed photographs due to excessive stereoscopic disparity decreased 70 % in 4 weeks. The participants also developed a preference for subjects that included clear depth differences and started to avoid photographing people because they looked unnatural in 3D photographs. They also regarded flash-induced shadows and edge violations problematic because of the unnatural effects in the photographs. We propose in-camera assistance tools for 3D cameras to make 3D photography easier.

  3. Subjective quality and depth assessment in stereoscopic viewing of volume-rendered medical images

    NASA Astrophysics Data System (ADS)

    Rousson, Johanna; Couturou, Jeanne; Vetsuypens, Arnout; Platisa, Ljiljana; Kumcu, Asli; Kimpe, Tom; Philips, Wilfried

    2014-03-01

    No study to-date explored the relationship between perceived image quality (IQ) and perceived depth (DP) in stereoscopic medical images. However, this is crucial to design objective quality metrics suitable for stereoscopic medical images. This study examined this relationship using volume-rendered stereoscopic medical images for both dual- and single-view distortions. The reference image was modified to simulate common alterations occurring during the image acquisition stage or at the display side: added white Gaussian noise, Gaussian filtering, changes in luminance, brightness and contrast. We followed a double stimulus five-point quality scale methodology to conduct subjective tests with eight non-expert human observers. The results suggested that DP was very robust to luminance, contrast and brightness alterations and insensitive to noise distortions until standard deviation σ=20 and crosstalk rates of 7%. In contrast, IQ seemed sensitive to all distortions. Finally, for both DP and IQ, the Friedman test indicated that the quality scores for dual-view distortions were significantly worse than scores for single-view distortions for multiple blur levels and crosstalk impairments. No differences were found for most levels of brightness, contrast and noise distortions. So, DP and IQ didn't react equivalently to identical impairments, and both depended whether dual- or single-view distortions were applied.

  4. Rate-Distortion Optimization for Stereoscopic Video Streaming with Unequal Error Protection

    NASA Astrophysics Data System (ADS)

    Tan, A. Serdar; Aksay, Anil; Akar, Gozde Bozdagi; Arikan, Erdal

    2008-12-01

    We consider an error-resilient stereoscopic streaming system that uses an H.264-based multiview video codec and a rateless Raptor code for recovery from packet losses. One aim of the present work is to suggest a heuristic methodology for modeling the end-to-end rate-distortion (RD) characteristic of such a system. Another aim is to show how to make use of such a model to optimally select the parameters of the video codec and the Raptor code to minimize the overall distortion. Specifically, the proposed system models the RD curve of video encoder and performance of channel codec to jointly derive the optimal encoder bit rates and unequal error protection (UEP) rates specific to the layered stereoscopic video streaming. We define analytical RD curve modeling for each layer that includes the interdependency of these layers. A heuristic analytical model of the performance of Raptor codes is also defined. Furthermore, the distortion on the stereoscopic video quality caused by packet losses is estimated. Finally, analytical models and estimated single-packet loss distortions are used to minimize the end-to-end distortion and to obtain optimal encoder bit rates and UEP rates. The simulation results clearly demonstrate the significant quality gain against the nonoptimized schemes.

  5. Web GIS in practice VII: stereoscopic 3-D solutions for online maps and virtual globes

    USGS Publications Warehouse

    Boulos, Maged N.K.; Robinson, Larry R.

    2009-01-01

    Because our pupils are about 6.5 cm apart, each eye views a scene from a different angle and sends a unique image to the visual cortex, which then merges the images from both eyes into a single picture. The slight difference between the right and left images allows the brain to properly perceive the 'third dimension' or depth in a scene (stereopsis). However, when a person views a conventional 2-D (two-dimensional) image representation of a 3-D (three-dimensional) scene on a conventional computer screen, each eye receives essentially the same information. Depth in such cases can only be approximately inferred from visual clues in the image, such as perspective, as only one image is offered to both eyes. The goal of stereoscopic 3-D displays is to project a slightly different image into each eye to achieve a much truer and realistic perception of depth, of different scene planes, and of object relief. This paper presents a brief review of a number of stereoscopic 3-D hardware and software solutions for creating and displaying online maps and virtual globes (such as Google Earth) in "true 3D", with costs ranging from almost free to multi-thousand pounds sterling. A practical account is also given of the experience of the USGS BRD UMESC (United States Geological Survey's Biological Resources Division, Upper Midwest Environmental Sciences Center) in setting up a low-cost, full-colour stereoscopic 3-D system.

  6. Research and Construction Lunar Stereoscopic Visualization System Based on Chang'E Data

    NASA Astrophysics Data System (ADS)

    Gao, Xingye; Zeng, Xingguo; Zhang, Guihua; Zuo, Wei; Li, ChunLai

    2017-04-01

    With lunar exploration activities carried by Chang'E-1, Chang'E-2 and Chang'E-3 lunar probe, a large amount of lunar data has been obtained, including topographical and image data covering the whole moon, as well as the panoramic image data of the spot close to the landing point of Chang'E-3. In this paper, we constructed immersive virtual moon system based on acquired lunar exploration data by using advanced stereoscopic visualization technology, which will help scholars to carry out research on lunar topography, assist the further exploration of lunar science, and implement the facilitation of lunar science outreach to the public. In this paper, we focus on the building of lunar stereoscopic visualization system with the combination of software and hardware by using binocular stereoscopic display technology, real-time rendering algorithm for massive terrain data, and building virtual scene technology based on panorama, to achieve an immersive virtual tour of the whole moon and local moonscape of Chang'E-3 landing point.

  7. Perfect 3-D movies and stereoscopic movies on TV and projection screens: an appraisement

    NASA Astrophysics Data System (ADS)

    Klein, Susanne; Dultz, Wolfgang

    1990-09-01

    Since the invention of stereoscopy (WHEATSTONE 1838) reasons for and against 3-dimensional images have occupied the literature, but there has never been much doubt about the preference of autostereoscopic systems showing a scene which is 3-dimensional and true to life from all sides (perfect 3-dimensional image, HESSE 1939), especially since most stereoscopic movies of the past show serious imperfections with respect to image quality and technical operation. Leave aside that no convincing perfect 3D-TV-system is in sight, there are properties f the stereoscopic movie which are advantageous to certain representations on TV and important for the 3-dimensional motion picture. In this paper we investigate the influence of apparent motions of 3-dimensional images and classify the different projection systems with respect to presence and absence of these spectacular illusions. Apparent motions bring dramatic effects into stereoscopic movies which cannot be created with perfect 3-dimensional systems. In this study we describe their applications and limits for television.

  8. A dataset of stereoscopic images and ground-truth disparity mimicking human fixations in peripersonal space

    NASA Astrophysics Data System (ADS)

    Canessa, Andrea; Gibaldi, Agostino; Chessa, Manuela; Fato, Marco; Solari, Fabio; Sabatini, Silvio P.

    2017-03-01

    Binocular stereopsis is the ability of a visual system, belonging to a live being or a machine, to interpret the different visual information deriving from two eyes/cameras for depth perception. From this perspective, the ground-truth information about three-dimensional visual space, which is hardly available, is an ideal tool both for evaluating human performance and for benchmarking machine vision algorithms. In the present work, we implemented a rendering methodology in which the camera pose mimics realistic eye pose for a fixating observer, thus including convergent eye geometry and cyclotorsion. The virtual environment we developed relies on highly accurate 3D virtual models, and its full controllability allows us to obtain the stereoscopic pairs together with the ground-truth depth and camera pose information. We thus created a stereoscopic dataset: GENUA PESTO—GENoa hUman Active fixation database: PEripersonal space STereoscopic images and grOund truth disparity. The dataset aims to provide a unified framework useful for a number of problems relevant to human and computer vision, from scene exploration and eye movement studies to 3D scene reconstruction.

  9. The right view from the wrong location: depth perception in stereoscopic multi-user virtual environments.

    PubMed

    Pollock, Brice; Burton, Melissa; Kelly, Jonathan W; Gilbert, Stephen; Winer, Eliot

    2012-04-01

    Stereoscopic depth cues improve depth perception and increase immersion within virtual environments (VEs). However, improper display of these cues can distort perceived distances and directions. Consider a multi-user VE, where all users view identical stereoscopic images regardless of physical location. In this scenario, cues are typically customized for one "leader" equipped with a head-tracking device. This user stands at the center of projection (CoP) and all other users ("followers") view the scene from other locations and receive improper depth cues. This paper examines perceived depth distortion when viewing stereoscopic VEs from follower perspectives and the impact of these distortions on collaborative spatial judgments. Pairs of participants made collaborative depth judgments of virtual shapes viewed from the CoP or after displacement forward or backward. Forward and backward displacement caused perceived depth compression and expansion, respectively, with greater compression than expansion. Furthermore, distortion was less than predicted by a ray-intersection model of stereo geometry. Collaboration times were significantly longer when participants stood at different locations compared to the same location, and increased with greater perceived depth discrepancy between the two viewing locations. These findings advance our understanding of spatial distortions in multi-user VEs, and suggest a strategy for reducing distortion.

  10. Characterization of mutagenic activity in grain-based coffee-substitute blends and instant coffees

    SciTech Connect

    Johansson, M.A.E.; Knize, M.G.; Felton, J.S.; Jagerstad, M.

    1994-06-01

    Several grain-based coffee-substitute blends and instant coffees showed a mutagenic response in the Ames/Salmonella test using TA98, YG1024 and YG1O29 with metabolic activation. The beverage powders contained 150 to 500 TA98 and 1150 to 4050 YG1024 revertant colonies/gram, respectively. The mutagenic activity in the beverage powders was shown to be stable to heat and the products varied in resistance to acid nitrite treatment. Characterization of the mutagenic activity, using HPLC-and the Ames test of the collected fractions, showed the coffee-substitutes and instant coffees contain several mutagenic compounds, which are most likely aromatic amines.

  11. An evaluation of instant and regular coffee in the Ames mutagenicity test.

    PubMed

    Aeschbacher, H U; Würzner, H P

    1980-02-01

    High concentrations of "home brew" and instant coffe induced revertants 2--3-fold the spontaneous level with the Ames Salmonella tester strain TA 100 but not with the strains TA 98, TA 1535, TA 1537 and TA 1538. This borderline effect, which may also have been due to non-mutagenic interactions (false positives) occurred only at bacterial levels of coffees and was completely abolished in the presence of the microsomal "metabolic activation system". Negative results were obtained in host-mediated assays when mice received up to 6 g instant coffee/kg body weight. An extrapolation in respect of possible carcinogenic risks is dubious.

  12. Optimal evolution models for quantum tomography

    NASA Astrophysics Data System (ADS)

    Czerwiński, Artur

    2016-02-01

    The research presented in this article concerns the stroboscopic approach to quantum tomography, which is an area of science where quantum physics and linear algebra overlap. In this article we introduce the algebraic structure of the parametric-dependent quantum channels for 2-level and 3-level systems such that the generator of evolution corresponding with the Kraus operators has no degenerate eigenvalues. In such cases the index of cyclicity of the generator is equal to 1, which physically means that there exists one observable the measurement of which performed a sufficient number of times at distinct instants provides enough data to reconstruct the initial density matrix and, consequently, the trajectory of the state. The necessary conditions for the parameters and relations between them are introduced. The results presented in this paper seem to have considerable potential applications in experiments due to the fact that one can perform quantum tomography by conducting only one kind of measurement. Therefore, the analyzed evolution models can be considered optimal in the context of quantum tomography. Finally, we introduce some remarks concerning optimal evolution models in the case of n-dimensional Hilbert space.

  13. Continuous monitoring of prostate position using stereoscopic and monoscopic kV image guidance

    SciTech Connect

    Stevens, M. Tynan R.; Parsons, Dave D.; Robar, James L.

    2016-05-15

    Purpose: To demonstrate continuous kV x-ray monitoring of prostate motion using both stereoscopic and monoscopic localizations, assess the spatial accuracy of these techniques, and evaluate the dose delivered from the added image guidance. Methods: The authors implemented both stereoscopic and monoscopic fiducial localizations using a room-mounted dual oblique x-ray system. Recently developed monoscopic 3D position estimation techniques potentially overcome the issue of treatment head interference with stereoscopic imaging at certain gantry angles. To demonstrate continuous position monitoring, a gold fiducial marker was placed in an anthropomorphic phantom and placed on the Linac couch. The couch was used as a programmable translation stage. The couch was programmed with a series of patient prostate motion trajectories exemplifying five distinct categories: stable prostate, slow drift, persistent excursion, transient excursion, and high frequency excursions. The phantom and fiducial were imaged using 140 kVp, 0.63 mAs per image at 1 Hz for a 60 s monitoring period. Both stereoscopic and monoscopic 3D localization accuracies were assessed by comparison to the ground-truth obtained from the Linac log file. Imaging dose was also assessed, using optically stimulated luminescence dosimeter inserts in the phantom. Results: Stereoscopic localization accuracy varied between 0.13 ± 0.05 and 0.33 ± 0.30 mm, depending on the motion trajectory. Monoscopic localization accuracy varied from 0.2 ± 0.1 to 1.1 ± 0.7 mm. The largest localization errors were typically observed in the left–right direction. There were significant differences in accuracy between the two monoscopic views, but which view was better varied from trajectory to trajectory. The imaging dose was measured to be between 2 and 15 μGy/mAs, depending on location in the phantom. Conclusions: The authors have demonstrated the first use of monoscopic localization for a room-mounted dual x-ray system. Three

  14. Can the perception of depth in stereoscopic images be influenced by 3D sound?

    NASA Astrophysics Data System (ADS)

    Turner, Amy; Berry, Jonathan; Holliman, Nick

    2011-03-01

    The creation of binocular images for stereoscopic display has benefited from significant research and commercial development in recent years. However, perhaps surprisingly, the effect of adding 3D sound to stereoscopic images has rarely been studied. If auditory depth information can enhance or extend the visual depth experience it could become an important way to extend the limited depth budget on all 3D displays and reduce the potential for fatigue from excessive use of disparity. Objective: As there is limited research in this area our objective was to ask two preliminary questions. First what is the smallest difference in forward depth that can be reliably detected using 3D sound alone? Second does the addition of auditory depth information influence the visual perception of depth in a stereoscopic image? Method: To investigate auditory depth cues we use a simple sound system to test the experimental hypothesis that: participants will perform better than chance at judging the depth differences between two speakers a set distance apart. In our second experiment investigating both auditory and visual depth cues we setup a sound system and a stereoscopic display to test the experimental hypothesis that: participants judge a visual stimulus to be closer if they hear a closer sound when viewing the stimulus. Results: In the auditory depth cue trial every depth difference tested gave significant results demonstrating that the human ear can hear depth differences between physical sources as short as 0.25 m at 1 m. In our trial investigating whether audio information can influence the visual perception of depth we found that participants did report visually perceiving an object to be closer when the sound was played closer to them even though the image depth remained unchanged. Conclusion: The positive results in the two trials show that we can hear small differences in forward depth between sound sources and suggest that it could be practical to extend the apparent

  15. Investigation of flow structure on a stationary and pitching delta wing of moderate sweep angle using stereoscopic particle image velocimetry

    NASA Astrophysics Data System (ADS)

    Goruney, Tunc

    Near-surface flow patterns along a basic delta wing of moderate sweep angle, representative of key features of Unmanned Combat Air Vehicles (UCAVs) and Micro Air Vehicles (MAVs), are visualized by a technique of high-image-density digital particle image velocimetry (DPIV), which provides quantitative representations of the whole-field flow patterns. Due to the highly three-dimensional nature of the flow patterns, they are also visualized by stereoscopic particle image velocimetry (SPIV). Qualitative dye visualization is employed to complement the DPIV technique. The flow structure is represented by patterns of dye, velocity vectors, streamwise, transverse and out-of-plane velocity components, streamline topology and vorticity. The surface topology, i.e., surface streamlines, and patterns of surface velocity and vorticity oriented normal to the surface of the wing, are investigated by making use of topological rules and critical point theory. For the case of DPIV measurements, the focus is on the time evolution of the surface topology during relaxation of the flow after termination of a pitching maneuver, for a wide range of pitch rates. It is demonstrated that there exists a critical universal state, which marks an abrupt transformation between two distinctly different states of the near-surface pattern of critical points. Moreover, an approach that predicts the occurrence of three-dimensional separation from the surface of the wing, for a wide range of pitch rate, is introduced. For the case of SPIV measurements, the relationship between the three-dimensional flow structure above the surface of the wing and the near-surface topology along the wing has been established, at successive instants following termination of the maneuver. Features of the leading-edge vortex and its breakdown location were quantitatively determined at the termination of the pitching maneuver. For the relaxed state of the flow structure, there is a reference elevation above the wing surface

  16. Mobile Immersion: An Experiment Using Mobile Instant Messenger to Support Second-Language Learning

    ERIC Educational Resources Information Center

    Lai, Arthur

    2016-01-01

    Immersion has been an acclaimed approach for second-language acquisition, but is not available to most students. The idea of this study was to create a mobile immersion environment on a smartphone using a mobile instant messenger, WhatsApp™. Forty-five Form-1 (7th grade) students divided into the Mobile Group and Control Group participated in a…

  17. Integrating Instant Messenger into Online Office Hours to Enhance Synchronous Online Interaction in Teacher Education

    ERIC Educational Resources Information Center

    Lih-Ching, Chen Wang; Beasley, William

    2006-01-01

    Modern communication technologies have modified the tradition of instructor's office hours in numerous ways. This article explores the use of Instant Messenger (IM) software in the context of "online office hours". The authors discuss strengths and weaknesses of IM interactions for instructor/student communication, and examine a sample of such…

  18. Social and Virtual Networks: Evaluating Synchronous Online Interviewing Using Instant Messenger

    ERIC Educational Resources Information Center

    Hinchcliffe, Vanessa; Gavin, Helen

    2009-01-01

    This paper describes an evaluation of the quality and utility of synchronous online interviewing for data collection in social network research. Synchronous online interviews facilitated by Instant Messenger as the communication medium, were undertaken with ten final year university students. Quantitative and qualitative content analysis of…

  19. Corrective Feedback via Instant Messenger Learning Activities in NS-NNS and NNS-NNS Dyads

    ERIC Educational Resources Information Center

    Sotillo, Susana

    2005-01-01

    This exploratory study examines corrective feedback in native speaker-nonnative speaker (NS-NNS) and NNS-NNS dyads while participants were engaged in communicative and problem-solving activities via "Yahoo! Instant Messenger" (YIM). As "negotiation of meaning" studies of the 1990s have shown, linguistic items which learners negotiate in…

  20. Instant Messaging in On-Site and Online Classes in Higher Education

    ERIC Educational Resources Information Center

    Jeong, Wooseob

    2007-01-01

    In the past, instant messaging (IM) was considered "a teen thing" rather than a serious tool for education. As teenagers who rely on IM as a communication tool arrive on college campuses, however, IM usage will become more prevalent in higher education. IM has generated increasing awareness of its value for educational purposes despite its slow…

  1. Picture This: Digital and Instant Photography Activities for Early Childhood Learning.

    ERIC Educational Resources Information Center

    Entz, Susan; Galarza, Sheri Lyn

    This book is designed to introduce teachers to digital technology and its uses in the classroom as a new teaching tool that can create curriculum, document learning, provide instant feedback, and share student growth with parents. The book's introduction details the ease in which digital technology can be incorporated into the curriculum.…

  2. Efficacy of Barabasz's Instant Alert Hypnosis in the Treatment of ADHD with Neurotherapy.

    ERIC Educational Resources Information Center

    Anderson, Kathryn; Barabasz, Marianne; Barabasz, Arreed; Warner, Dennis

    2000-01-01

    Tested use of instant alert hypnosis on 16 children diagnosed with attention deficit disorder. Found that EEG beta-theta ratio means were significantly higher in trials of neurotherapy combined with alert hypnosis than neurotherapy alone. Beta was significantly enhanced, whereas theta was inhibited. Identified improved treatment efficacy and…

  3. Becoming Embedded: Incorporating Instant Messaging and the Ongoing Evolution of a Virtual Reference Service

    ERIC Educational Resources Information Center

    Stormont, Sam

    2010-01-01

    The creation of an instant messaging (IM) service is described. The challenges encountered in developing, launching, and maintaining the project are examined and include technical support, archiving, balancing different formats, privacy, assessment, training, and the effectiveness of the IM channel. The process of choosing an aggregator and a…

  4. WhatsApp Goes to School: Mobile Instant Messaging between Teachers and Students

    ERIC Educational Resources Information Center

    Bouhnik, Dan; Deshen, Mor

    2014-01-01

    WhatsApp is a Smartphone application for instant messaging. Lately the application's popularity has risen. One of the unique features of the application is its ability to enhance communication within a group. Classroom communication between teaching faculty and high school students using WhatsApp has not yet, to our knowledge, been researched…

  5. Social and Virtual Networks: Evaluating Synchronous Online Interviewing Using Instant Messenger

    ERIC Educational Resources Information Center

    Hinchcliffe, Vanessa; Gavin, Helen

    2009-01-01

    This paper describes an evaluation of the quality and utility of synchronous online interviewing for data collection in social network research. Synchronous online interviews facilitated by Instant Messenger as the communication medium, were undertaken with ten final year university students. Quantitative and qualitative content analysis of…

  6. How Instant Messaging Affects the Satisfaction of Virtual Interpersonal Behavior of Taiwan Junior High School Students

    ERIC Educational Resources Information Center

    Lin, Chien-Huang; Sun, Ya-Chung; Lee, Yueh-Chiang; Wu, Shih-Chia

    2007-01-01

    Although Instant Messaging (IM) has established itself as one of the most popular modes of communication, little empirical research has explored how adolescents are affected by its use to satisfy their virtual interpersonal relationships. This research investigates cause and effect in the satisfaction of these relationships among adolescents in…

  7. Azoreductase activity in bacteria associated with the greening of instant chocolate puddings.

    PubMed Central

    Dykes, G A; Timm, R G; von Holy, A

    1994-01-01

    Pseudomonas sp. strain AZR1 and Klebsiella sp. strain AZR2 were isolated from reconstituted instant chocolate puddings that had turned green and were found to have azoreductase activity. This activity was inducible and NADH dependent. Differences in dye reduction rates between the two strains were apparent, and substrate specificity related to dye structure was observed. PMID:8085839

  8. Efficacy of Barabasz's Instant Alert Hypnosis in the Treatment of ADHD with Neurotherapy.

    ERIC Educational Resources Information Center

    Anderson, Kathryn; Barabasz, Marianne; Barabasz, Arreed; Warner, Dennis

    2000-01-01

    Tested use of instant alert hypnosis on 16 children diagnosed with attention deficit disorder. Found that EEG beta-theta ratio means were significantly higher in trials of neurotherapy combined with alert hypnosis than neurotherapy alone. Beta was significantly enhanced, whereas theta was inhibited. Identified improved treatment efficacy and…

  9. Instant Messaging in On-Site and Online Classes in Higher Education

    ERIC Educational Resources Information Center

    Jeong, Wooseob

    2007-01-01

    In the past, instant messaging (IM) was considered "a teen thing" rather than a serious tool for education. As teenagers who rely on IM as a communication tool arrive on college campuses, however, IM usage will become more prevalent in higher education. IM has generated increasing awareness of its value for educational purposes despite its slow…

  10. Can Students Really Multitask? An Experimental Study of Instant Messaging while Reading

    ERIC Educational Resources Information Center

    Bowman, Laura L.; Levine, Laura E.; Waite, Bradley M.; Gendron, Michael

    2010-01-01

    Students often "multitask" with electronic media while doing schoolwork. We examined the effects of one form of media often used in such multitasking, instant messaging (IM). We predicted that students who engaged in IMing while reading a typical academic psychology passage online would take longer to read the passage and would perform more poorly…

  11. Is Instant Messaging the Same in Every Language? A Basque Perspective

    ERIC Educational Resources Information Center

    Cenoz, Jasone; Bereziartua, Garbiñe

    2016-01-01

    This study focuses on computer mediated communication (CMC) in instant messaging using the Basque language in a context where exposure to English is very limited outside the classroom. This context provides an opportunity to analyze the universality of linguistic features identified in CMC in English. The corpus consists of 54 naturalistic dyadic…

  12. Can Students Really Multitask? An Experimental Study of Instant Messaging while Reading

    ERIC Educational Resources Information Center

    Bowman, Laura L.; Levine, Laura E.; Waite, Bradley M.; Gendron, Michael

    2010-01-01

    Students often "multitask" with electronic media while doing schoolwork. We examined the effects of one form of media often used in such multitasking, instant messaging (IM). We predicted that students who engaged in IMing while reading a typical academic psychology passage online would take longer to read the passage and would perform more poorly…

  13. Know Your Noodles! Assessing Variations in Sodium Content of Instant Noodles across Countries.

    PubMed

    Farrand, Clare; Charlton, Karen; Crino, Michelle; Santos, Joseph; Rodriguez-Fernandez, Rodrigo; Ni Mhurchu, Cliona; Webster, Jacqui

    2017-06-16

    Reducing salt intake is a cost-effective public health intervention to reduce the global burden of non-communicable disease (NCDs). Ultra-processed foods contribute ~80% of dietary salt in high income countries, and are becoming prominent in low-middle income countries. Instant noodle consumption is particularly high in the Asia Pacific region. The aim of this study was to compare the sodium content of instant noodles sold worldwide to identify potential for reformulation. Analysis was undertaken for 765 instant noodle products from 10 countries using packaged food composition databases of ultra-processed foods compiled by the Global Food Monitoring Group (GFMG) and national shop survey data. Sodium levels were high and variable, within and between countries. Instant noodles in China had the highest mean sodium content (1944 mg/100 g; range: 397-3678/100 g) compared to New Zealand (798 mg/100 g; range: 249-2380 mg/100 g). Average pack size ranged from 57 g (Costa Rica) to 98 g (China). The average packet contributed 35% to 95% of the World Health Organization recommended daily salt intake of <5 g. Forty-one percent of products met the Pacific Island (PICs) regional sodium targets, 37% met the South Africa 2016 targets, and 62% met the UK 2017 targets. This study emphasises a need for stronger regulation and closer monitoring to drive rigorous reformulation of salt in ultra-processed foods.

  14. Know Your Noodles! Assessing Variations in Sodium Content of Instant Noodles across Countries

    PubMed Central

    Farrand, Clare; Charlton, Karen; Crino, Michelle; Santos, Joseph; Rodriguez-Fernandez, Rodrigo; Ni Mhurchu, Cliona; Webster, Jacqui

    2017-01-01

    Reducing salt intake is a cost-effective public health intervention to reduce the global burden of non-communicable disease (NCDs). Ultra-processed foods contribute ~80% of dietary salt in high income countries, and are becoming prominent in low-middle income countries. Instant noodle consumption is particularly high in the Asia Pacific region. The aim of this study was to compare the sodium content of instant noodles sold worldwide to identify potential for reformulation. Analysis was undertaken for 765 instant noodle products from 10 countries using packaged food composition databases of ultra-processed foods compiled by the Global Food Monitoring Group (GFMG) and national shop survey data. Sodium levels were high and variable, within and between countries. Instant noodles in China had the highest mean sodium content (1944 mg/100 g; range: 397–3678/100 g) compared to New Zealand (798 mg/100 g; range: 249–2380 mg/100 g). Average pack size ranged from 57 g (Costa Rica) to 98 g (China). The average packet contributed 35% to 95% of the World Health Organization recommended daily salt intake of <5 g. Forty-one percent of products met the Pacific Island (PICs) regional sodium targets, 37% met the South Africa 2016 targets, and 62% met the UK 2017 targets. This study emphasises a need for stronger regulation and closer monitoring to drive rigorous reformulation of salt in ultra-processed foods. PMID:28621720

  15. Students and Instant Messaging: A Survey of Current Use and Demands for Higher Education

    ERIC Educational Resources Information Center

    de Bakker, Gijs; Sloep, Peter; Jochems, Wim

    2007-01-01

    Instant messaging (IM) is the term used to describe the technology through which "users can set up a list of partners who will be able to receive notes that pop up on their screens the moment one of them writes and hits the send button". While early use could be described as mainly for fun, IM today is a serious communication medium.…

  16. Is Instant Messaging the Same in Every Language? A Basque Perspective

    ERIC Educational Resources Information Center

    Cenoz, Jasone; Bereziartua, Garbiñe

    2016-01-01

    This study focuses on computer mediated communication (CMC) in instant messaging using the Basque language in a context where exposure to English is very limited outside the classroom. This context provides an opportunity to analyze the universality of linguistic features identified in CMC in English. The corpus consists of 54 naturalistic dyadic…

  17. Corrective Feedback via Instant Messenger Learning Activities in NS-NNS and NNS-NNS Dyads

    ERIC Educational Resources Information Center

    Sotillo, Susana

    2005-01-01

    This exploratory study examines corrective feedback in native speaker-nonnative speaker (NS-NNS) and NNS-NNS dyads while participants were engaged in communicative and problem-solving activities via "Yahoo! Instant Messenger" (YIM). As "negotiation of meaning" studies of the 1990s have shown, linguistic items which learners negotiate in…

  18. Instant Experience in Clinical Trials: A Computer-Aided Simulation Technique

    ERIC Educational Resources Information Center

    Simpson, Michael A.

    1976-01-01

    Describes "Instant Experience," a simulation and game method in which students are given information about a promising new drug and asked to design a protocol for a clinical trial of the drug. Evaluation of a trial workshop showed positive response to the method. Educational goals to be achieved through its use are noted. (JT)

  19. Real-Time Computer-Mediated Communication: Email and Instant Messaging Simulation

    ERIC Educational Resources Information Center

    Newman, Amy

    2007-01-01

    As computer-mediated communication becomes increasingly prevalent in the workplace, students need to apply effective writing principles to today's technologies. Email, in particular, requires interns and new hires to manage incoming messages, use an appropriate tone, and craft clear, concise messages. In addition, with instant messaging (IM)…

  20. Constant Companions: Instant Messaging Conversations as Sustainable Supportive Study Structures amongst Undergraduate Peers

    ERIC Educational Resources Information Center

    Timmis, Sue

    2012-01-01

    Universities are facing severe cuts in funding and a transformation of both the economic model underpinning higher education and the relationship between students, tutors and universities and the traditional forms of support for students' learning may be eroded. At the same time, mobile communications, instant messaging and social networking are…