Journal articles: 'Active stereoscopy'

1

Wiegelmann, T., B. Inhester, and L. Feng. "Solar stereoscopy – where are we and what developments do we require to progress?" Annales Geophysicae 27, no. 7 (July 23, 2009): 2925–36. http://dx.doi.org/10.5194/angeo-27-2925-2009.

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Abstract. Observations from the two STEREO-spacecraft give us for the first time the possibility to use stereoscopic methods to reconstruct the 3-D solar corona. Classical stereoscopy works best for solid objects with clear edges. Consequently an application of classical stereoscopic methods to the faint structures visible in the optically thin coronal plasma is by no means straight forward and several problems have to be treated adequately: 1) First there is the problem of identifying one-dimensional structures – e.g. active region coronal loops or polar plumes- from the two individual EUV-images observed with STEREO/EUVI. 2) As a next step one has the association problem to find corresponding structures in both images. This becomes more difficult as the angle between STEREO-A and B increases. 3) Within the reconstruction problem stereoscopic methods are used to compute the 3-D-geometry of the identified structures. Without any prior assumptions, e.g., regarding the footpoints of coronal loops, the reconstruction problem has not one unique solution. 4) One has to estimate the reconstruction error or accuracy of the reconstructed 3-D-structure, which depends on the accuracy of the identified structures in 2-D, the separation angle between the spacecraft, but also on the location, e.g., for east-west directed coronal loops the reconstruction error is highest close to the loop top. 5) Eventually we are not only interested in the 3-D-geometry of loops or plumes, but also in physical parameters like density, temperature, plasma flow, magnetic field strength etc. Helpful for treating some of these problems are coronal magnetic field models extrapolated from photospheric measurements, because observed EUV-loops outline the magnetic field. This feature has been used for a new method dubbed "magnetic stereoscopy". As examples we show recent application to active region loops.

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Mitiche, Amar, and Jean-Michel Létang. "Stereokinematic analysis of visual data in active convergent stereoscopy." Robotics and Autonomous Systems 25, no. 1-2 (October 1998): 43–71. http://dx.doi.org/10.1016/s0921-8890(98)00033-5.

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Aschwanden, Markus J., and T. S. Bastian. "VLA stereoscopy of solar active regions. 1: Method and tests." Astrophysical Journal 426 (May 1994): 425. http://dx.doi.org/10.1086/174078.

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Icasio-Hernández, O., Y. I. Curiel-Razo, C. C. Almaraz-Cabral, S. R. Rojas-Ramirez, and J. J. González-Barbosa. "MEASUREMENT ERROR WITH DIFFERENT COMPUTER VISION TECHNIQUES." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W7 (September 12, 2017): 227–35. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w7-227-2017.

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The goal of this work is to offer a comparative of measurement error for different computer vision techniques for 3D reconstruction and allow a metrological discrimination based on our evaluation results. The present work implements four 3D reconstruction techniques: passive stereoscopy, active stereoscopy, shape from contour and fringe profilometry to find the measurement error and its uncertainty using different gauges. We measured several dimensional and geometric known standards. We compared the results for the techniques, average errors, standard deviations, and uncertainties obtaining a guide to identify the tolerances that each technique can achieve and choose the best.

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Ulrich, Luca, Enrico Vezzetti, Sandro Moos, and Federica Marcolin. "Analysis of RGB-D camera technologies for supporting different facial usage scenarios." Multimedia Tools and Applications 79, no. 39-40 (August 11, 2020): 29375–98. http://dx.doi.org/10.1007/s11042-020-09479-0.

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Abstract Recently a wide variety of applications has been developed integrating 3D functionalities. Advantages given by the possibility of relying on depth information allows the developers to design new algorithms and to improve the existing ones. In particular, for what concerns face morphology, 3D has led to the possibility to obtain face depth maps highly close to reality and consequently an improvement of the starting point for further analysis such as Face Detection, Face Authentication, Face Identification and Face Expression Recognition. The development of the aforementioned applications would have been impossible without the progress of sensor technologies for obtaining 3D information. Several solutions have been adopted over time. In this paper, emphasis is put on passive stereoscopy, structured light, time-of-flight (ToF) and active stereoscopy, namely the most used technologies for the cameras design and fulfilment according to the literature. The aim of this article is to investigate facial applications and to examine 3D camera technologies to suggest some guidelines for addressing the correct choice of a 3D sensor according to the application that has to be developed.

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Keebler, Joseph R., Florian Jentsch, and David Schuster. "The Effects of Video Game Experience and Active Stereoscopy on Performance in Combat Identification Tasks." Human Factors: The Journal of the Human Factors and Ergonomics Society 56, no. 8 (May 12, 2014): 1482–96. http://dx.doi.org/10.1177/0018720814535248.

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Neupane, Chiranjivi, Anand Koirala, Zhenglin Wang, and Kerry Brian Walsh. "Evaluation of Depth Cameras for Use in Fruit Localization and Sizing: Finding a Successor to Kinect v2." Agronomy 11, no. 9 (September 5, 2021): 1780. http://dx.doi.org/10.3390/agronomy11091780.

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Eight depth cameras varying in operational principle (stereoscopy: ZED, ZED2, OAK-D; IR active stereoscopy: Real Sense D435; time of flight (ToF): Real Sense L515, Kinect v2, Blaze 101, Azure Kinect) were compared in context of use for in-orchard fruit localization and sizing. For this application, a specification on bias-corrected root mean square error of 20 mm for a camera-to-fruit distance of 2 m and operation under sunlit field conditions was set. The ToF cameras achieved the measurement specification, with a recommendation for use of Blaze 101 or Azure Kinect made in terms of operation in sunlight and in orchard conditions. For a camera-to-fruit distance of 1.5 m in sunlight, the Azure Kinect measurement achieved an RMSE of 6 mm, a bias of 17 mm, an SD of 2 mm and a fill rate of 100% for depth values of a central 50 × 50 pixels group. To enable inter-study comparisons, it is recommended that future assessments of depth cameras for this application should include estimation of a bias-corrected RMSE and estimation of bias on estimated camera-to-fruit distances at 50 cm intervals to 3 m, under both artificial light and sunlight, with characterization of image distortion and estimation of fill rate.

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Aschwanden, Markus J., and T. S. Bastian. "VLA stereoscopy of solar active regions. 2: Altitude, relative motion, and center-to-limb darkening of 20 centimeter emission." Astrophysical Journal 426 (May 1994): 434. http://dx.doi.org/10.1086/174079.

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9

Liu, Y. "Coronal magnetic fields inferred from IR wavelength and comparison with EUV observations." Annales Geophysicae 27, no. 7 (July 13, 2009): 2771–77. http://dx.doi.org/10.5194/angeo-27-2771-2009.

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Abstract. Spectropolarimetry using IR wavelength of 1075 nm has been proved to be a powerful tool for directly mapping solar coronal magnetic fields including transverse component directions and line-of-sight component intensities. Solar tomography, or stereoscopy based on EUV observations, can supply 3-D information for some magnetic field lines in bright EUV loops. In a previous paper \\citep{liu08} the locations of the IR emission sources in the 3-D coordinate system were inferred from the comparison between the polarization data and the potential-field-source-surface (PFSS) model, for one of five west limb regions in the corona (Lin et al., 2004). The paper shows that the region with the loop system in the active region over the photospheric area with strong magnetic field intensity is the region with a dominant contribution to the observed Stokes signals. So, the inversion of the measured Stokes parameters could be done assuming that most of the signals come from a relatively thin layer over the area with a large photospheric magnetic field strength. Here, the five limb coronal regions are studied together in order to study the spatial correlation between the bright EUV loop features and the inferred IR emission sources. It is found that, for the coronal regions above the stronger photospheric magnetic fields, the locations of the IR emission sources are closer to or more consistent with the bright EUV loop locations than those above weaker photospheric fields. This result suggests that the structures of the coronal magnetic fields observed at IR and EUV wavelengths may be different when weak magnetic fields present there.

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10

Vasilyev, Roman, Maksim Artamonov, Aleksandr Beletsky, Olga Zorkaltseva, Evgeniya Komarova, Irina Medvedeva, Aleksandr Mikhalev, et al. "Scientific goals of optical instruments of the National Heliogeophysical Complex." Solnechno-Zemnaya Fizika 6, no. 2 (June 27, 2020): 105–22. http://dx.doi.org/10.12737/szf-62202008.

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Studies of the upper atmosphere have to be performed using optical photometric and spectrometric means. Modern devices allow precise photometry of the glow of the night atmosphere — airglow — with high temporal spatial and spectral resolution. As a result, the obtained airglow parameters make it possible to determine the physicochemical properties of the upper atmosphere and observe their variation under the influence of various factors. The National Heliogeophysical Complex, which is being created in Eastern Siberia, is therefore to include a certain set of modern optical instruments. The paper presents the main phenomena that will be investigated by the optical instruments of the complex, provides information on their composition and scientific goals, presents the results of preliminary studies performed using a prototype of the instruments. As a result of the studies, the presence of a significant (about 10 m/sec) vertical wind at various altitudes (100 and 250 km) was established, the importance of taking into account the vertical wind to study the vertical dynamics of the charged component was demonstrated. The long-term dynamics of the vertical wind at an altitude of about 100 km has a pronounced seasonal variations and the absence of diurnal variations, whereas the dynamics of the vertical wind at an altitude of 250 km has a pronounced diurnal variations, which is mostly clearly defined in winter. This suggests the presumed presence of vertical circulation cells at various altitude levels. The possibilities of optical stereoscopy and differential image analysis methods are demonstrated, as applied to the study of fast luminous formations and conducting active ground and space experiments to modify Earth's ionosphere. We report the results of the determination of a three-dimensional picture of a long-lived meteor track with the use of two wide-angle cameras. We propose an algorithm that allows us to get a stereo image of events occurring in the upper atmosphere, recorded simultaneously from different observation points. The joint work of the tools of this complex and the development of cooperation with third-party organizations are shown to be a good enough direction for further study of the vertical dynamics of Earth’s upper atmosphere and space weather phenomena.

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Vasilyev, Roman, Maksim Artamonov, Aleksandr Beletsky, Olga Zorkaltseva, Evgeniya Komarova, Irina Medvedeva, Aleksandr Mikhalev, et al. "Scientific goals of optical instruments of the National Heliogeophysical Complex." Solar-Terrestrial Physics 6, no. 2 (June 27, 2020): 84–97. http://dx.doi.org/10.12737/stp-62202008.

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Studies of the upper atmosphere have to be performed using optical photometric and spectrometric means. Modern devices allow precise photometry of the glow of the night atmosphere — airglow — with high temporal spatial and spectral resolution. As a result, the obtained airglow parameters make it possible to determine the physicochemical properties of the upper atmosphere and observe their variation under the influence of various factors. The National Heliogeophysical Complex, which is being created in Eastern Siberia, is therefore to include a certain set of modern optical instruments. The paper presents the main phenomena that will be investigated by the optical instruments of the complex, provides information on their composition and scientific goals, presents the results of preliminary studies performed using a prototype of the instruments. As a result of the studies, the presence of a significant (about 10 m/sec) vertical wind at various altitudes (100 and 250 km) was established, the importance of taking into account the vertical wind to study the vertical dynamics of the charged component was demonstrated. The long-term dynamics of the vertical wind at an altitude of about 100 km has a pronounced seasonal variations and the absence of diurnal variations, whereas the dynamics of the vertical wind at an altitude of 250 km has a pronounced diurnal variations, which is mostly clearly defined in winter. This suggests the presumed presence of vertical circulation cells at various altitude levels. The possibilities of optical stereoscopy and differential image analysis methods are demonstrated, as applied to the study of fast luminous formations and conducting active ground and space experiments to modify Earth's ionosphere. We report the results of the determination of a three-dimensional picture of a long-lived meteor track with the use of two wide-angle cameras. We propose an algorithm that allows us to get a stereo image of events occurring in the upper atmosphere, recorded simultaneously from different observation points. The joint work of the tools of this complex and the development of cooperation with third-party organizations are shown to be a good enough direction for further study of the vertical dynamics of Earth’s upper atmosphere and space weather phenomena.

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12

Shestak, Sergey, Dae-Sik Kim, and Kyung-Hoon Cha. "Stereoscopic three-dimensional television using active glasses with switchable refraction." Journal of Electronic Imaging 24, no. 3 (May 12, 2015): 033006. http://dx.doi.org/10.1117/1.jei.24.3.033006.

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13

Eickelberg, Stefan, and Jianshuang Xu. "Active Depth Cuts Without Distortion of Stereoscopic Depth Reduce Annoyance." SMPTE Motion Imaging Journal 127, no. 2 (March 2018): 57–67. http://dx.doi.org/10.5594/jmi.2017.2743838.

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14

Xia Zhenping, 夏振平, 李晓华 Li Xiaohua, 陈磊 Chen Lei, and 汤四海 Tang Sihai. "Objective Evaluation of Flicker in Stereoscopic Display with Active Shutter Glasses." Acta Optica Sinica 33, no. 12 (2013): 1233001. http://dx.doi.org/10.3788/aos201333.1233001.

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Wu, Yanbing, Jun Jung Mok, Wei Wei, Yufan Du, Jinye Zhu, and Naifu Wu. "41.2:Invited Paper: An UHD Active Barrier Auto-Stereoscopic 3D Module." SID Symposium Digest of Technical Papers 45, no. 1 (June 2014): 584–87. http://dx.doi.org/10.1002/j.2168-0159.2014.tb00153.x.

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Wu, Sin Lin, Jorge E. Caviedes, Lina Karam, and Ingrid Heynderickx. "The Effect of Applying 2D Enhancement Algorithms on 3D Video Content." Journal of Electrical and Computer Engineering 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/601392.

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Enhancement algorithms are typically applied to video content to increase their appeal to viewers. Such algorithms are readily available in the literature and are already widely applied in, for example, commercially available TVs. On the contrary, not much research has been done on enhancing stereoscopic 3D video content. In this paper, we present research focused on the effect of applying enhancement algorithms used for 2D content on 3D side-by-side content. We evaluate both offline enhancement of video content based on proprietary enhancement algorithms and real-time enhancement in the TVs. This is done using stereoscopic TVs with active shutter glasses, viewed both in their 2D and 3D viewing mode. The results of this research show that 2D enhancement algorithms are a viable first approach to enhance 3D content. In addition to video quality degradation due to the loss of spatial resolution as a consequence of the 3D video format, brightness reduction inherent to polarized or shutter glasses similarly degrades video quality. We illustrate the benefit of providing brightness enhancement for stereoscopic displays.

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Ntalianis, Klimis S., Anastasios D. Doulamis, Nikolaos D. Doulamis, Nikos E. Mastorakis, and Athanasios S. Drigas. "Unsupervised Segmentation of Stereoscopic Video Objects: Constrained Segmentation Fusion Versus Greedy Active Contours." Journal of Signal Processing Systems 81, no. 2 (July 9, 2014): 153–81. http://dx.doi.org/10.1007/s11265-014-0921-0.

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Tang, Chenxiao, Cees J. Van Westen, Hakan Tanyas, and Victor G. Jetten. "Analysing post-earthquake landslide activity using multi-temporal landslide inventories near the epicentral area of the 2008 Wenchuan earthquake." Natural Hazards and Earth System Sciences 16, no. 12 (December 12, 2016): 2641–55. http://dx.doi.org/10.5194/nhess-16-2641-2016.

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Abstract. Large earthquakes in mountainous regions may trigger thousands of landslides, some active for years. We analysed the changes in landslide activity near the epicentre of the 2008 Wenchuan earthquake by generating five landslide inventories for different years through stereoscopic digital visual image interpretation. From May 2008 to April 2015, 660 new landslides occurred outside the co-seismic landslide areas. In April 2015, the number of active landslides had gone down to 66, less than 1 % of the co-seismic landslides, but still much higher than the pre-earthquake levels. We expect that the landslide activity will continue to decay, but may be halted if extreme rainfall events occur.

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Cerutti, Juan José, Costantino Sardu, Gioacchino Cafiero, and Gaetano Iuso. "Active Flow Control on a Square-Back Road Vehicle." Fluids 5, no. 2 (April 21, 2020): 55. http://dx.doi.org/10.3390/fluids5020055.

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An experimental investigation focused on the manipulation of the wake generated by a square back car model is presented. Four continuously-blowing rectangular slot jets were mounted on the rear face of a 1:10 commercial van model. Load cell measurements evidence drag reduction for different forcing configurations, reaching a maximum of 12% for lateral and bottom jets blowing. The spectral analysis of the pressure fluctuations evidence, for all forced cases, an energy attenuation with respect to the natural case, especially close to the shedding frequency. An energy budget highlighted the most efficient forcing configurations accounting for both the drag reduction and the power required to feed the blowing system. Two main configurations are considered: the maximum drag reduction and the best compromise, yielding 5% drag reduction and a convenient energy balance. Particle Image Velocimetry (pPIV) and stereoscopic PIV (sPIV) experiments were performed allowing the three-dimensional reconstruction of the wake in the three considered configurations. Consistently with static and fluctuating pressure measurements, sPIV results reveal a dramatic change in the wake structure when the jets blow in the maximum drag reduction configuration. Conversely, the best compromise configuration reveals a wake structure similar to the natural one.

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Rushton, S. K., and J. M. Harris. "Active Control of Heading and Depth." Perception 26, no. 1_suppl (August 1997): 334. http://dx.doi.org/10.1068/v970364.

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The addition of depth information has been reported to improve performance on a locomotor heading judgement task in a cloud of dots. Van den Berg and Brenner [1994 Nature (London)371 700 – 702] used stereoscopic disparity as a depth cue. Coding dots with disparity provides both cues for depth order and for identity between successive frames (each dot may be disambiguated from its 2-D neighbours by its 3-D position). Here, we attempted to determine the relative importance of depth and identity, by dissociating disparity-depth and disparity-identity. We employed an active steering task that dissociates gaze and heading direction. Participants underwent simulated (18 Hz) locomotion through a cloud (100 dots, lifetime 440 ms) at 2 m s−1 for 8 s from an initial trajectory 15 deg (±20%) to the left or to the right of a target tower. Heading was adjusted with a joystick and simulated gaze was continuously computer adjusted so as to keep the tower centred on the projected display (20 deg horizontal). Mean unsigned heading error (gaze-heading angle) over the time course provided a performance measure. Four types of stimuli were used: (i) veridical disparity depth; (ii) non-veridical disparity (disparity and associated motion-in-depth was randomly assigned to each point in the display); (iii) the left half image of the previous condition to both eyes; (iv) synoptic images (no disparity). No marked advantage was observed when the display contained veridical disparity, and non-veridical disparity produced only a minor impairment in performance in a subset of conditions. We suggest that depth information per se may not be utilised in the perception and control of heading.

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Shao, Xu Dong, and Yang Liu. "Implementation of Monitoring and Management for Professional Mobile Application Adapting to Scenarios Switch." Applied Mechanics and Materials 651-653 (September 2014): 1860–63. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.1860.

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In order to effectively monitor, manage and prosper professional mobile application, this paper analyze the reasons of shorting for monitoring and management of mobile application on current technologies. Also, based on mechanisms of mandatory access control in user space or kernel space, including scenarios context switcher, we implement an active stereoscopic framework for monitoring and management of mobile application adapting to situations changing. Besides monitoring & management of application, the framework can support application for user with new services adapting new environment.

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Xia Zhenping, 夏振平, 李晓华 Li Xiaohua, 陈磊 Chen Lei, and 王坚 Wang Jian. "Study on the Effect of Ambient Light Flicker in Stereoscopic Display with Active Shutter Glasses." Acta Optica Sinica 34, no. 7 (2014): 0733002. http://dx.doi.org/10.3788/aos201434.0733002.

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Aflaki, Payman, Miska M. Hannuksela, Hamed Sarbolandi, and Moncef Gabbouj. "Simultaneous 2D and 3D perception for stereoscopic displays based on polarized or active shutter glasses." Journal of Visual Communication and Image Representation 25, no. 4 (May 2014): 622–31. http://dx.doi.org/10.1016/j.jvcir.2013.03.014.

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Ezhov, Vasily A. "Active distant binocular filter with complementary nematic liquid crystal structures for observation of millisecond stereoscopic images." Optical Engineering 58, no. 10 (October 11, 2019): 1. http://dx.doi.org/10.1117/1.oe.58.10.103101.

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Sawada, Shigeki, Hiroshi Okazaki, Masahito Okumura, Tokiyoshi Matsuda, Mutsumi Kimura, Hideki Tanaka, and Tetsurou Matsumoto. "P-1: Current-Supplying Driving Method of Active-Matrix Ionic Polymer-Metal Composites for Stereoscopic Displays." SID Symposium Digest of Technical Papers 46, no. 1 (June 2015): 1119–22. http://dx.doi.org/10.1002/sdtp.10000.

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Gibaldi, Agostino, Andrea Canessa, Manuela Chessa, Marco Fato, Fabio Solari, and Silvio Sabatini. "The GENUA PESTO Database - GENoa hUman Active fixation database: PEripersonal space STereoscopic images and grOund truth disparity." Journal of Vision 17, no. 10 (August 31, 2017): 1067. http://dx.doi.org/10.1167/17.10.1067.

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Van Pelt, Stan, and W. Pieter Medendorp. "Gaze-Centered Updating of Remembered Visual Space During Active Whole-Body Translations." Journal of Neurophysiology 97, no. 2 (February 2007): 1209–20. http://dx.doi.org/10.1152/jn.00882.2006.

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Various cortical and sub-cortical brain structures update the gaze-centered coordinates of remembered stimuli to maintain an accurate representation of visual space across eyes rotations and to produce suitable motor plans. A major challenge for the computations by these structures is updating across eye translations. When the eyes translate, objects in front of and behind the eyes’ fixation point shift in opposite directions on the retina due to motion parallax. It is not known if the brain uses gaze coordinates to compute parallax in the translational updating of remembered space or if it uses gaze-independent coordinates to maintain spatial constancy across translational motion. We tested this by having subjects view targets, flashed in darkness in front of or behind fixation, then translate their body sideways, and subsequently reach to the memorized target. Reach responses showed parallax-sensitive updating errors: errors increased with depth from fixation and reversed in lateral direction for targets presented at opposite depths from fixation. In a series of control experiments, we ruled out possible biasing factors such as the presence of a fixation light during the translation, the eyes accompanying the hand to the target, and the presence of visual feedback about hand position. Quantitative geometrical analysis confirmed that updating errors were better described by using gaze-centered than gaze-independent coordinates. We conclude that spatial updating for translational motion operates in gaze-centered coordinates. Neural network simulations are presented suggesting that the brain relies on ego-velocity signals and stereoscopic depth and direction information in spatial updating during self-motion.

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Aschwanden, Markus J., Jean-Pierre Wuelser, Nariaki V. Nitta, James R. Lemen, and Anne Sandman. "FIRST THREE-DIMENSIONAL RECONSTRUCTIONS OF CORONAL LOOPS WITH THESTEREO A+BSPACECRAFT. III. INSTANT STEREOSCOPIC TOMOGRAPHY OF ACTIVE REGIONS." Astrophysical Journal 695, no. 1 (March 27, 2009): 12–29. http://dx.doi.org/10.1088/0004-637x/695/1/12.

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Aschwanden, Markus J., David Alexander, Neal Hurlburt, Jeffrey S. Newmark, Werner M. Neupert, J. A. Klimchuk, and G. Allen Gary. "Three‐dimensional Stereoscopic Analysis of Solar Active Region Loops. II.SOHO/EIT Observations at Temperatures of 1.5–2.5 MK." Astrophysical Journal 531, no. 2 (March 10, 2000): 1129–49. http://dx.doi.org/10.1086/308483.

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Wong, Jing-Ying, Chun-Chieh Yip, Su-Ting Yong, Andy Chan, Sien-Ti Kok, Teck-Leong Lau, Mohammed T. Ali, and Essameldin Gouda. "BIM-VR Framework for Building Information Modelling in Engineering Education." International Journal of Interactive Mobile Technologies (iJIM) 14, no. 06 (April 17, 2020): 15. http://dx.doi.org/10.3991/ijim.v14i06.13397.

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With the advancement of information technology, Building Information Modeling (BIM) is evolving fast and play an essential role in Architecture, Engineering, Construction, Owner and Operators (AECOO) industry. Universities play an important role in the current BIM transition in construction projects as well as to embrace Industry 4.0. In this research, immersive Virtual Reality (VR) in BIM offer a unique, supportive environment for the user experience in visualizing and collecting data from the model. With Virtual Reality (VR), engineering education has a major breakthrough. Immersive interactions, stereoscopic 3D, real time multisensory simulations, virtual explorations, synchronous communications, data analytics and visual analysis – all these are impossible without VR. VR offers a student-centred learning environment that promotes active and collaborative learning, situated within simulated real-world contexts.

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Danishevskiy, O. V., A. V. Parfenov, and V. V. Stankevich. "MODERN SOLUTIONS IN THE FIELD OF ROBOTIC VISION TO CREATE A UNIVERSAL CYBERNETIC PLATFORM." Issues of radio electronics, no. 5 (June 8, 2019): 32–38. http://dx.doi.org/10.21778/2218-5453-2019-5-32-38.

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The article describes modern solutions used to create vision systems for autonomous robotic complexes, a device for controlling video sensors, methods for obtaining stereo images, processing and further using them in the navigation system. A functional diagram of the organization of the robotic vision system, which is part of the NIIVK M. A. Kartsev Computing System Research and Development Institute, platform, a brief description of its functions and principles of action. The proposed solution involves placing a pair of optical sensors in the head of the robot, simulating the binocular stereoscopic vision inherent in higher animals. A feature of the development is the rejection of the use of laser, infrared, radio frequency, ultrasound and other active emitters, which reduces energy costs and the cost of products without reducing their reliability.

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Aschwanden, Markus J., Jeffrey S. Newmark, Jean‐Pierre Delaboudiniere, Werner M. Neupert, J. A. Klimchuk, G. Allen Gary, Fabrice Portier‐Fozzani, and Arik Zucker. "Three‐dimensional Stereoscopic Analysis of Solar Active Region Loops. I.SOHO/EIT Observations at Temperatures of (1.0–1.5) x 106K." Astrophysical Journal 515, no. 2 (April 20, 1999): 842–67. http://dx.doi.org/10.1086/307036.

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Banik, Prabir, Arunava Bhadra, and Abhijit Bhattacharyya. "Interpreting correlated observations of cosmic rays and gamma-rays from Centaurus A with a proton blazar inspired model." Monthly Notices of the Royal Astronomical Society 500, no. 1 (October 28, 2020): 1087–94. http://dx.doi.org/10.1093/mnras/staa3343.

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ABSTRACT The nearest active radio galaxy Centaurus (Cen) A is a gamma-ray emitter in GeV–TeV energy scale. The high energy stereoscopic system (HESS) and non-simultaneous Fermi–Large Area Telescope observation indicate an unusual spectral hardening above few GeV energies in the gamma-ray spectrum of Cen A. Very recently the HESS observatory resolved the kilo parsec (kpc)-scale jets in Centaurus A at TeV energies. On the other hand, the Pierre Auger Observatory (PAO) detects a few ultrahigh energy cosmic ray (UHECR) events from Cen-A. The proton blazar inspired model, which considers acceleration of both electrons and hadronic cosmic rays in active galactic nuclei (AGN) jet, can explain the observed coincident high-energy neutrinos and gamma-rays from Ice-cube detected AGN jets. Here, we have employed the proton blazar inspired model to explain the observed GeV–TeV gamma-ray spectrum features including the spectrum hardening at GeV energies along with the PAO observation on cosmic rays from Cen-A. Our findings suggest that the model can explain consistently the observed electromagnetic spectrum in combination with the appropriate number of UHECRs from Cen A.

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Gupta, Reena, Richa Jangra, Gaurav Dubey, Ramesh Hooda, and Nirmal Parmar. "Efficacy of vision therapy in impaired stereoscopic depth with intermittent exotropia (true divergence excess) with unilateral amblyopia: a case report." International Journal Of Community Medicine And Public Health 7, no. 2 (January 28, 2020): 773. http://dx.doi.org/10.18203/2394-6040.ijcmph20200466.

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Divergence excess (DE) can be described clinically as exotropia at far greater than the near deviation by at least 10 prism dioptres (PD). We are reporting a rare case of 25-year-old female visited in the eye department for a routine eye check-up with a history of decreased vision in one eye. On examination, it was detected as a case of unilateral amblyopia with intermittent exotropia of true divergence excess with high accommodative-convergence over accommodation (AC/A) ratio. The patient was asymptomatic from exo-deviation due to the presence of binocular vision and good fusional reserve. The patient was started on active conventional vision therapy along with occlusion therapy. Post 16 weeks of constant therapy, a vision assessment with complete squint assessment along with binocular vision tests were performed. The result interprets to support the use of active conventional vision therapy as an integral part of the clinical treatment of amblyopia and intermittent exotropia. The rate of recovery of several monocular functions monitored during the vision therapy period provides the evidence of neural plasticity at multiple sites in the visual pathway in this adult amblyope. Therefore, if an ordered plan is being followed for the management of the patient of unilateral amblyopia and divergence excess, it can yield long-lasting improvement in visual acuity and binocular functions of any age.

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DE ALMEIDA, ULISSES BARRES. "RESULTS FROM MAGIC OBSERVATIONS OF EXTRAGALACTIC RELATIVISTIC SOURCES." International Journal of Modern Physics: Conference Series 08 (January 2012): 178–83. http://dx.doi.org/10.1142/s2010194512004576.

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The Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) experiment is an array of two 17-meter telescopes located in the Canary Island of La Palma that observes the very-high energy (VHE) gamma-ray sky in stereoscopic mode since 2009. MAGIC is distinguished by its low-energy threshold of approximately 50 GeV, which grants the system a unique potential in the study of distant extragalactic sources whose gamma-ray emission is significantly attenuated due to absorption by the extragalactic background light (EBL). The observation of non-thermal gamma rays in the GeV-TeV range from extragalactic sources is a characteristic signature of their relativistic nature and therefore fundamentally important for our understanding of the physics of these objects. Since the beginning of its stereo operation, MAGIC has observed a large number of active galactic nuclei (AGN) of different classes, including several blazars and distant quasars. In this paper we will review some of the most important results of these observations.

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KUO, CHUNG-HSIEN, YU-LIN TSAI, FANG-GHUN HUANG, and MING-YIH LEE. "DEVELOPMENT OF A SURGICAL NAVIGATION ROBOT USING IMAGE SERVO TRACKING TECHNIQUES." Biomedical Engineering: Applications, Basis and Communications 16, no. 03 (June 25, 2004): 120–32. http://dx.doi.org/10.4015/s1016237204000177.

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This paper presents the development of surgical navigation robot, which is designed based on the image servo tracking technique. The surgical navigation robot plays an important role to the computer aided surgery (CAS), since it provides the patient's space coordinate during surgical navigation stage in real-time. Especially, the proposed active image servo tracking based surgical navigation robot can track the surgical marker that is mounted on the patient's hard tissue of the surgical position, so that the navigation space can be automatically extended. The proposed surgical navigation robot system consists of the in-lab designed dual-axis eye-in-hand robot (EIHR), digital signal processor (DSP) based EIHR motion controller, image servo tracking and positioning software. The EIHR robot is composed of the dual-axis robot mechanics and two CCD cameras, which acts as the stereoscopic image capture platform. The DSP based EIHR motion controller is designed to control the EIHR robot in a desired velocity, so that the surgical marker can be dynamically tracked. The image servo tracking and positioning software is the kernel of this work, and it is composed of image capture and recognition module, fuzzy logic based surgical marker tracking module and surgical marker positioning module. The image capture and recognition module is developed to abstract the image features of the surgical marker. The intelligent fuzzy logic based surgical marker tracking module is capable of generating robot's control command so that the surgical marker can be tracked within the desired target window. In addition, the surgical marker positioning module is used to calculate the surgical marker's space coordinates in terms of the features of stereoscopic images and the robot's posture. Finally, the prototype had been finished, and the experiment results showed that proposed EIHR achieved 1.7 mm position error within 500 mm operation range.

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Kessler, Nivi, Rachel Armoza-Zvuloni, Siyuan Wang, Subhajit Basu, Peter K. Weber, Rhona K. Stuart, and Yeala Shaked. "Selective collection of iron-rich dust particles by natural Trichodesmium colonies." ISME Journal 14, no. 1 (September 24, 2019): 91–103. http://dx.doi.org/10.1038/s41396-019-0505-x.

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Abstract Dust is an important iron (Fe) source to the ocean, but its utilization by phytoplankton is constrained by rapid sinking and slow dissolution dust-bound iron (dust-Fe). Colonies of the globally important cyanobacterium, Trichodesmium, overcome these constraints by efficient dust capturing and active dust-Fe dissolution. In this study we examined the ability of Trichodesmium colonies to maximize their Fe supply from dust by selectively collecting Fe-rich particles. Testing for selectivity in particle collection, we supplied ~600 individual colonies, collected on multiple days from the Gulf of Aqaba, with natural dust and silica minerals that were either cleaned of or coated with Fe. Using a stereoscope, we counted the number of particles retained by each colony shortly after addition and following 24 h incubation with particles, and documented translocation of particles to the colony core. We observed a strong preference for Fe-rich particles over Fe-free particles in all tested parameters. Moreover, some colonies discarded the Fe-free particles they initially collected. The preferred collection of Fe-rich particles and disposal of Fe-free particles suggest that Trichodesmium can sense Fe and selectively choose Fe-rich dust particles. This ability assists Trichodesmium obtain Fe from dust and facilitate its growth and subsequent contribution to nutrient cycling and productivity in the ocean.

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Stepanov, D. N. "Method of calibrating an active optical stereoscopic system that consists of a monocular camera and structured illumination in the form of a line." Journal of Optical Technology 87, no. 4 (April 1, 2020): 230. http://dx.doi.org/10.1364/jot.87.000230.

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Yaseen, Kashaf. "Metagenomics of Mosquito-borne Flaviviruses in Various Geoclimatic Districts of Punjab, Pakistan." Pakistan Veterinary Journal 40, no. 04 (December 1, 2020): 407–12. http://dx.doi.org/10.29261/pakvetj/2020.091.

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Mosquitoes are highly active vectors capable of transmitting various pathogenic and infectious diseases to humans and animals. The present study was designed to identify the major species of mosquitoes and mosquito-borne flaviviruses (Saint Louis Encephalitis, West Nile and Dengue Viruses) prevalent in three districts of Punjab representing the three agro-geoclimatic zones viz; Multan, Chakwal and Jhang. The collected mosquitoes were stereoscopically identified to confirm the species and sex of the mosquitoes. Stereoscopic identification confirmed that female mosquitoes were 4334 out of 10675 (40.6%), 2242 out of 7296 (30%) and 2040 out of 6450 (31.6%) from districts Chakwal, Jhang and Multan, respectively. It was concluded that Culex species were present in abundance (73.2%) as compared to Aedes species (26.7%) in the selected study districts. The results of multiplex RT-PCR depicted that Dengue, West Nile, Japanese encephalitis and Saint Louis encephalitis viruses were prevalent in the mosquitoes of all three selected districts. However, the prevalence of mosquito-borne viruses insignificantly varied (P>0.05) among the three districts. This study has provided a better understanding of the prevailing mosquito species and mosquito-borne viruses in the study districts that can help to devise appropriate control measures

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Woods, Andrew J. "Sourcing and Qualifying Passive Polarised 3D TVs." Electronic Imaging 2021, no. 2 (January 18, 2021): 100–1. http://dx.doi.org/10.2352/issn.2470-1173.2021.2.sda-100.

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Millions of Stereoscopic 3D capable TVs were sold into the consumer market from 2007 through to 2016. A wide range of display technologies were supported including rear-projection DLP, Plasma, LCD and OLED. Some displays supported the Active 3D method using liquid-crystal shutter glasses, and some displays supported the Passive 3D method using circularly polarised 3D glasses. Displays supporting Full-HD and Ultra-HD (4K) resolution were available in sizes ranging from 32" to 86" diagonal. Unfortunately display manufacturers eventually changed their focus to promoting other display technologies and 2016 was the last year that new 3D TVs were made for the consumer market. Fortunately, there are still millions of 3D displays available through the secondhand- market, however it can be difficult to know which displays have 3D display support. This paper will provide a listing of specifically Passive 3D TVs manufactured by LG, however it has been our experience that the 3D quality varied considerably from one display to another hence it is necessary to qualify the quality of the 3D available on these displays using a testing technique that will be described in the paper.

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Krizek, Gerd Christian, Rene Hausleitner, Laura Böhme, and Cristina Olaverri-Monreal. "Empirical Analysis of Safe Distance Calculation by the Stereoscopic Capturing and Processing of Images Through the Tailigator System." Sensors 19, no. 22 (November 19, 2019): 5044. http://dx.doi.org/10.3390/s19225044.

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Driver disregard for the minimum safety distance increases the probability of rear-end collisions. In order to contribute to active safety on the road, we propose in this work a low-cost Forward Collision Warning system that captures and processes images. Using cameras located in the rear section of a leading vehicle, this system serves the purpose of discouraging tailgating behavior from the vehicle driving behind. We perform in this paper the pertinent field tests to assess system performance, focusing on the calculated distance from the processing of images and the error margins in a straight line, as well as in a curve. Based on the evaluation results, the current version of the Tailigator can be used at speeds up to 50 km per hour without any restrictions. The measurements showed similar characteristics both on the straight line and in the curve. At close distances, between 3 and 5 m, the values deviated from the real value. At average distances, around 10 to 15 m, the Tailigator achieved the best results. From distances higher than 20 m, the deviations increased steadily with the distance. We contribute to the state of the art with an innovative low-cost system to identify tailgating behavior and raise awareness, which works independently of the rear vehicle’s communication capabilities or equipment.

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Dotson*, Bradley, Camila Rey, Joonyup Kim, and Sara Patterson. "The Gene slm1-1 Regulates Abscission, Dehiscence, Meristem Arrest, and Apical Dominance in Arabidopsis thaliana." HortScience 39, no. 4 (July 2004): 848B—848. http://dx.doi.org/10.21273/hortsci.39.4.848b.

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Cell separation regulates basic developmental processes such as abscission and dehiscence and is one of the horticultural traits first to be selected by mankind. Abscission is characterized by an active cell separation process where organs are detached from the main body of the plant through the dissolution of the middle lamella. Crops with early abscission can have significant reduction in yield. For example, canola, Brassica napus, loses 5% to 10% of crop due to early pod shatter. By screening T-DNA mutagenized populations of A. thaliana for delayed abscission, we have identified several genes that regulate cell separation, slm1-1 (slender lasting inflorescence and meristem) is one such genes. During our investigation of slm1-1 we have employed phenotypic, physiological, genetic, and molecular assays. Phenotypically, slm1-1 displays traits such as delayed abscission of floral organs, lack of anther pollen dehiscence (making slm1-1 functionally male sterile), delayed meristem arrest, and strong apical dominance. Phenotypic characterization includes scanning electron microscopy, bright field microscopy, and stereoscope microscopy. Physiological assays include reporter gene expression and break strength analyses. Genetically, slm1-1 is regulated by a single recessive gene. Molecular assays characterizing slm1-1 include TAIL-PCR, RT-PCR, and preliminary microarray of abscission zones. We have also begun to map based cloning of slm1-1. We believe that understanding genes that regulate cell separation in A. thaliana will contribute to crop improvement. Applications could include reducing loss during harvesting, regulation of pollination, changes in branching patterns, and longevity of flowering.

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Muijres, Florian T., L. Christoffer Johansson, York Winter, and Anders Hedenström. "Comparative aerodynamic performance of flapping flight in two bat species using time-resolved wake visualization." Journal of The Royal Society Interface 8, no. 63 (May 4, 2011): 1418–28. http://dx.doi.org/10.1098/rsif.2011.0015.

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Bats are unique among extant actively flying animals in having very flexible wings, controlled by multi-jointed fingers. This gives the potential for fine-tuned active control to optimize aerodynamic performance throughout the wingbeat and thus a more efficient flight. But how bat wing performance scales with size, morphology and ecology is not yet known. Here, we present time-resolved fluid wake data of two species of bats flying freely across a range of flight speeds using stereoscopic digital particle image velocimetry in a wind tunnel. From these data, we construct an average wake for each bat species and speed combination, which is used to estimate the flight forces throughout the wingbeat and resulting flight performance properties such as lift-to-drag ratio ( L/D ). The results show that the wake dynamics and flight performance of both bat species are similar, as was expected since both species operate at similar Reynolds numbers ( Re ) and Strouhal numbers ( St ). However, maximum L/D is achieved at a significant higher flight speed for the larger, highly mobile and migratory bat species than for the smaller non-migratory species. Although the flight performance of these bats may depend on a range of morphological and ecological factors, the differences in optimal flight speeds between the species could at least partly be explained by differences in their movement ecology.

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Nogueira, Petrônio A. S., André V. G. Cavalieri, Peter Jordan, and Vincent Jaunet. "Large-scale streaky structures in turbulent jets." Journal of Fluid Mechanics 873 (June 24, 2019): 211–37. http://dx.doi.org/10.1017/jfm.2019.365.

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Streaks have been found to be an important part of wall-turbulence dynamics. In this paper, we extend the analysis for unbounded shear flows, in particular a Mach 0.4 round jet, using measurements taken using dual-plane, time-resolved, stereoscopic particle image velocimetry (PIV) taken at pairs of jet cross-sections, allowing the evaluation of the cross-spectral density of streamwise velocity fluctuations resolved into azimuthal Fourier modes. From the streamwise velocity results, two analyses are performed: the evaluation of wavenumber spectra (assuming Taylor’s hypothesis for the streamwise coordinate) and a spectral proper orthogonal decomposition (SPOD) of the velocity field using PIV planes in several axial stations. The methods complement each other, leading to the conclusion that large-scale streaky structures are also present in turbulent jets where they experience large growth in the streamwise direction, energetic structures extending up to eight diameters from the nozzle exit. Leading SPOD modes highlight the large-scale, streaky shape of the structures, whose aspect ratio (streamwise over azimuthal length) is approximately 15. The data were further analysed using SPOD, resolvent and transient growth analyses, good agreement being observed between the models and the leading SPOD mode for the wavenumbers considered. The models also indicate that the lift-up mechanism is active in turbulent jets, with streamwise vortices leading to streaks. The results show that large-scale streaks are a relevant part of the jet dynamics.

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Håkansson, Jonas, Anders Hedenström, York Winter, and L. Christoffer Johansson. "The wake of hovering flight in bats." Journal of The Royal Society Interface 12, no. 109 (August 2015): 20150357. http://dx.doi.org/10.1098/rsif.2015.0357.

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Hovering means stationary flight at zero net forward speed, which can be achieved by animals through muscle powered flapping flight. Small bats capable of hovering typically do so with a downstroke in an inclined stroke plane, and with an aerodynamically active outer wing during the upstroke. The magnitude and time history of aerodynamic forces should be reflected by vorticity shed into the wake. We thus expect hovering bats to generate a characteristic wake, but this has until now never been studied. Here we trained nectar-feeding bats, Leptonycteris yerbabuenae , to hover at a feeder and using time-resolved stereoscopic particle image velocimetry in conjunction with high-speed kinematic analysis we show that hovering nectar-feeding bats produce a series of bilateral stacked vortex loops. Vortex visualizations suggest that the downstroke produces the majority of the weight support, but that the upstroke contributes positively to the lift production. However, the relative contributions from downstroke and upstroke could not be determined on the basis of the wake, because wake elements from down- and upstroke mix and interact. We also use a modified actuator disc model to estimate lift force, power and flap efficiency. Based on our quantitative wake-induced velocities, the model accounts for weight support well (108%). Estimates of aerodynamic efficiency suggest hovering flight is less efficient than forward flapping flight, while the overall energy conversion efficiency (mechanical power output/metabolic power) was estimated at 13%.

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Fogagnolo, Paolo, Maurizio Digiuni, Giovanni Montesano, Chiara Rui, Marco Morales, and Luca Rossetti. "Compass fundus automated perimetry." European Journal of Ophthalmology 28, no. 5 (March 22, 2018): 481–90. http://dx.doi.org/10.1177/1120672118757667.

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Background: Compass (CenterVue, Padova, Italy) is a fundus automated perimeter which has been introduced in the clinical practice for glaucoma management in 2014. The aim of the article is to review Compass literature, comparing its performances against Humphrey Field Analyzer (Zeiss Humphrey Systems, Dublin, CA, USA). Results: Analyses on both normal and glaucoma subjects agree on the fact that Humphrey Field Analyzer and Compass are interchangeable, as the difference of their global indices is largely inferior than test -retest variability for Humphrey Field Analyzer. Compass also enables interesting opportunities for the assessment of morphology, and the integration between morphology and function on the same device. Conclusion: Visual field testing by standard automated perimetry is limited by a series of intrinsic factors related to the psychophysical nature of the examination; recent papers suggest that gaze tracking is closely related to visual field reliability. Compass, thanks to a retinal tracker and to the active dislocation of stimuli to compensate for eye movements, is able to provide visual fields unaffected by fixation instability. Also, the instrument is a true colour, confocal retinoscope and obtains high-quality 60° × 60° photos of the central retina and stereo-photos details of the optic nerve. Overlapping the image of the retina to field sensitivity may be useful in ascertaining the impact of comorbidities. In addition, the recent introduction of stereoscopic photography may be very useful for better clinical examination.

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Goto, Hideaki. "Seafloor Stereo Map of Coastal Areas for Geomorphological Studies." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-98-2019.

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Abstract. Topographical anaglyph maps produced from digital elevation model (DEM) are an easy and practical means of inland topography and seafloor observations (Goto, 2016). Since the 2000s, several coastal DEMs surveyed by multi-beam sound systems have been stored, though submarine topographic features have been popularly represented by contour lines in the previous century. Various DEM-based visual maps including shaded relief or stereo maps with contour lines have been adapted to observe inland topography (Awata, 2017); however, they have been rarely used to express slope shade with contour lines in coastal areas. Since the development of submarine topography above &minus;120&thinsp;m has become relevant for sea-level changes after the last glacial age, deep-sea features such as cliffs and terraces could provide essential information on topographical evolution and crustal movement. Therefore, we produced a stereo image map of slope shade and contour lines in a coastal area based on DEM. Although Louis Ducas du Hauron patented the original idea of producing anaglyphs in 1891(Waker and Dodge, 2001), anaglyph seafloor maps expressing slope shade and contour lines from DEM are new as well as are effective for understanding the geomorphic features of submerged terraces and the broad deformation of the oceanic bed because they enable us to identify small topographic features, such as submerged coral crests and height differences in the wide area. We studied the area around Inazejima and Iheyajima islands distributed in the north of Okinawa prefecture, southwest Japan. We found it difficult to understand the active tectonics of Nansei–Shoto arc based on only the isolated small islands; thus, we focused on the submerged marine terraces widely developed around these islands to reveal the depth distribution of paleo-shorelines. The Japan Coast Gard (JCG) conducted a multi-beam survey along the northwestern coast of Okinawa island from 2008 to 2012 (Yasuhara, 2013). The JAMSTEC (2016) stored and disseminated information for the rock and sediment core samples as well as the results of the multi-beam survey on their website, “Data and Sample Research System for Whole Cruise Information in JAMSTEC.” We retrieved these data from the JCG and JAMSTEC to generate 1.44-smesh (approximately 44&thinsp;m) and 2-s-mesh (approximately 65&thinsp;m) seafloor DEMs, respectively. We combined these DEMs with a 500-m-mesh DEM (J-EGG500) published by JCG, which were subsequently overlapped in a decreasing resolution. We imported these seafloor DEMs into Simple DEM Viewer&reg; to produce an anaglyph map that was overlapped onto the black and white slope shading base map and contour lines for stereoscopic analysis with red-cyan glasses. Interpretation of the map revealed that the several submerged marine terraces were distributed around the islands, and the NWW-trending active faults cut and deformed these terraces in the southwest off the coast of Izena island. Stereoscopic analysis with contour lines enabled us to obtain the height difference of the submerged terraces between the west and east sides of Iheya island, which were estimated to have formed during the last glacial age based on the terrace platform depth.

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Zhu, Liye, Maria Val Martin, Luciana V. Gatti, Ralph Kahn, Arsineh Hecobian, and Emily V. Fischer. "Development and implementation of a new biomass burning emissions injection height scheme (BBEIH v1.0) for the GEOS-Chem model (v9-01-01)." Geoscientific Model Development 11, no. 10 (October 11, 2018): 4103–16. http://dx.doi.org/10.5194/gmd-11-4103-2018.

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Abstract. Biomass burning is a significant source of trace gases and aerosols to the atmosphere, and the evolution of these species depends acutely on where they are injected into the atmosphere. GEOS-Chem is a chemical transport model driven by assimilated meteorological data that is used to probe a variety of scientific questions related to atmospheric composition, including the role of biomass burning. This paper presents the development and implementation of a new global biomass burning emissions injection scheme in the GEOS-Chem model. The new injection scheme is based on monthly gridded Multi-angle Imaging SpectroRadiometer (MISR) global plume-height stereoscopic observations in 2008. To provide specific examples of the impact of the model updates, we compare the output from simulations with and without the new MISR-based injection height scheme to several sets of observations from regions with active fires. Our comparisons with Arctic Research on the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) aircraft observations show that the updated injection height scheme can improve the ability of the model to simulate the vertical distribution of peroxyacetyl nitrate (PAN) and carbon monoxide (CO) over North American boreal regions in summer. We also compare a simulation for October 2010 and 2011 to vertical profiles of CO over the Amazon Basin. When coupled with larger emission factors for CO, a simulation that includes the new injection scheme also better matches selected observations in this region. Finally, the improved injection height improves the simulation of monthly mean surface CO over California during July 2008, a period with large fires.

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Cunha, Nathalie C., Adivaldo H. Fonseca, Jania Rezende, Tatiana Rozental, Alexsandra R. M. Favacho, Jairo D. Barreira, Carlos L. Massard, and Elba R. S. Lemos. "First identification of natural infection of Rickettsia rickettsii in the Rhipicephalus sanguineus tick, in the State of Rio de Janeiro." Pesquisa Veterinária Brasileira 29, no. 2 (February 2009): 105–8. http://dx.doi.org/10.1590/s0100-736x2009000200003.

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The Brazilian Spotted Fever (BSF) is a zoonotic disease caused by Rickettsia rickettsii and transmitted by ticks of the genus Amblyomma, more frequently, Amblyomma cajennense. The aim of this paper was to report the first molecular detection of R. rickettsii on R. sanguineus naturally infected in Rio de Janeiro, Brazil. Ticks were collected from dogs in a rural region of Resende municipality, Rio de Janeiro State, Brazil (22º30'9.46"S, 44º42'44.29"WO), where occurred five human cases of BSF in 2006. The ticks were identified under a stereoscopic microscope and separated in pools by stages, species and sex. DNA extraction was carried out using QIAamp DNA Mini Kit (QIAGEN®). The DNA was submitted to PCR amplification using 04 set of primers: Rr190.70p/Rr190.602n (OmpA, 532bp), BG1-21/BG2-20 (OmpB, 650bp), Tz15/Tz16 (17 kDa protein-encoding gene, 246bp) and RpCS.877p/RpCS.1258n (gltA, 381bp). PCR products were separated by electrophoresis on 1% agarose gels and visualized under ultraviolet light with ethidium bromide. PCR products of the expected sizes were purified by QIAquick® and sequenced by ABI PRISM®. The generated nucleotide sequences were edited with using Bioedit® software and compared with the corresponding homologous sequences available through GenBank, using Discontiguous Mega Blast (http://www.ncbi.nlm.nih.gov). It was confirmed R. rickettsii by sequencing of the material (GenBank FJ356230). The molecular characterization of R. rickettsii in the tick R. sanguineus emphasizes the role of dogs as carriers of ticks from the environment to home. Moreover, this result suggests that there is a considerable chance for active participation of R. sanguineus as one of tick species in the transmission of R. ricketsii to human being in the Brazilian territory.

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Chang, Chen-Wei, Shih-Ching Yeh, and Mengtong Li. "The Adoption of a Virtual Reality–Assisted Training System for Mental Rotation: A Partial Least Squares Structural Equation Modeling Approach." JMIR Serious Games 8, no. 1 (January 17, 2020): e14548. http://dx.doi.org/10.2196/14548.

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Background Virtual reality (VR) technologies have been developed to assist education and training. Although recent research suggested that the application of VR led to effective learning and training outcomes, investigations concerning the acceptance of these VR systems are needed to better urge learners and trainees to be active adopters. Objective This study aimed to create a theoretical model to examine how determining factors from relevant theories of technology acceptance can be used to explain the acceptance of a novel VR-assisted mental rotation (MR) training system created by our research team to better understand how to encourage learners to use VR technology to enhance their spatial ability. Methods Stereo and interactive MR tasks based on Shepard and Metzler’s pencil and paper test for MR ability were created. The participants completed a set of MR tasks using 3D glasses and stereoscopic display and a 6-degree-of-freedom joystick controller. Following task completion, psychometric constructs from theories and previous studies (ie, perceived ease of use, perceived enjoyment, attitude, satisfaction, and behavioral intention to use the system) were used to measure relevant factors influencing behavior intentions. Results The statistical technique of partial least squares structural equation modeling was applied to analyze the data. The model explained 47.7% of the novel, VR-assisted MR training system’s adoption intention, which suggests that the model has moderate explanatory power. Direct and indirect effects were also interpreted. Conclusions The findings of this study have both theoretical and practical importance not only for MR training but also for other VR-assisted education. The results can extend current theories from the context of information systems to educational and training technology, specifically for the use of VR-assisted systems and devices. The empirical evidence has practical implications for educators, technology developers, and policy makers regarding MR training.

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Journal articles on the topic 'Active stereoscopy'

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