WorldWideScience

Sample records for length mm camera

  1. Superconducting magnet for gyrotron tube with 4 mm wave length

    International Nuclear Information System (INIS)

    Zhu Xuewu; Pu Men; Chen Jian; Liu Jianmin; Shi Qingju

    1988-03-01

    In this paper a superconducting magnet for gyrotron tube with 4mm wave length is described. It can provide a uniform magnetic field (B 0 ) of 3T in resonant cavity area. Its uniform area width is 6 cm and uniformity is better than ±0.16%. The uniform magnetic field can also to be adjusted into a gradient field and ΔB/B 0 ≥8.5%. The uniform area width of magnetic field (B k ) in the cathode area is 4 cm. Its uniformity is ±(1.0∼1.8)%. B k /B 0 can be adjusted in the region of 1/6∼1/15. The magnet is energized by four power sources. As optimum form of the magnetic field has been adjusted, the magnet can operate closely. The magnet will coordinate with the gyrotron tube to do ECRH physical experiment on the HL-1 Tokamak

  2. Modification of Hack Saw Blade Support 'REMOR 400' from the Length of 650 mm to 450 mm

    International Nuclear Information System (INIS)

    Sagino, Abdul-Hafid

    2005-01-01

    REMOR 400 type is the hack saw machine for cutting large work piece. The capacity of cutting is 310 mm diameter. The length of the blade is 650 mm (26 inches). For cutting small work piece (≤ 150 mm), the use of this blade is not efficient because the blade is relatively expensive. To solve this problem, the modification of the blade support is performed so that REMOR 400 machine can use the blade of 450 mm which is cheaper and easier to find in the market. (author)

  3. THERMAL EFFECTS ON CAMERA FOCAL LENGTH IN MESSENGER STAR CALIBRATION AND ORBITAL IMAGING

    Directory of Open Access Journals (Sweden)

    S. Burmeister

    2018-04-01

    Full Text Available We analyse images taken by the MErcury Surface, Space ENviorment, GEochemistry, and Ranging (MESSENGER spacecraft for the camera’s thermal response in the harsh thermal environment near Mercury. Specifically, we study thermally induced variations in focal length of the Mercury Dual Imaging System (MDIS. Within the several hundreds of images of star fields, the Wide Angle Camera (WAC typically captures up to 250 stars in one frame of the panchromatic channel. We measure star positions and relate these to the known star coordinates taken from the Tycho-2 catalogue. We solve for camera pointing, the focal length parameter and two non-symmetrical distortion parameters for each image. Using data from the temperature sensors on the camera focal plane we model a linear focal length function in the form of f(T = A0 + A1 T. Next, we use images from MESSENGER’s orbital mapping mission. We deal with large image blocks, typically used for the production of a high-resolution digital terrain models (DTM. We analyzed images from the combined quadrangles H03 and H07, a selected region, covered by approx. 10,600 images, in which we identified about 83,900 tiepoints. Using bundle block adjustments, we solved for the unknown coordinates of the control points, the pointing of the camera – as well as the camera’s focal length. We then fit the above linear function with respect to the focal plane temperature. As a result, we find a complex response of the camera to thermal conditions of the spacecraft. To first order, we see a linear increase by approx. 0.0107 mm per degree temperature for the Narrow-Angle Camera (NAC. This is in agreement with the observed thermal response seen in images of the panchromatic channel of the WAC. Unfortunately, further comparisons of results from the two methods, both of which use different portions of the available image data, are limited. If leaving uncorrected, these effects may pose significant difficulties in

  4. Stress Analysis on Single Cobalt/Chrome Prosthesis With a 15-mm Cantilever Placed Over 10/13/15-mm-length Implants: A Simulated Photoelastic Model Study.

    Science.gov (United States)

    Gastaldo, José Fábio Guastelli; Pimentel, Angélica Castro; Gomes, Maria Helena; Sendyk, Wilson Roberto; Laganá, Dalva Cruz

    2015-12-01

    The aim of study was to assess the stress around 10/13/15-mm implants in the mandibular area with a 15-mm cantilevered acrylic-resin-coated prostheses following the application force, using the photoelasticity method. Three photoelastic mandibular models were created containing 10-, 13-, and 15-mm implants in length and 3.75 mm in diameter. The implants had bore internal hex connections and were placed parallel to the intermental region. Abutments with 1-mm high cuffs were placed over the implants, and a single cobalt/chrome metallic prosthesis with a 15-mm cantilever, coated with thermoplastic acrylic resin, was placed on top. Loads of 1.0 and 3.0 bars were applied, and the images were photographed and assessed by photoelasticity method. The greatest stress levels were observed for the 10-mm implants. The stress pattern was the same regardless of implant length; only the magnitude of the stress along the implant body revealed changes. Increased implant length played a role in reducing stress on the investigated area of the model, and the 15-mm implants exhibited the best performance in regard to stress distribution. The highest stress levels were found in the implants closest to the cantilever and the central implant. The longest implants were more favorable in regard to the stress distribution on the peri-implant support structures in the 15-mm cantilevered prosthesis under loads.

  5. Influence of Implant Design (Cylindrical and Conical) in the Load Transfer Surrounding Long (13mm) and Short (7mm) Length Implants: A Photoelastic Analysis.

    Science.gov (United States)

    Gehrke, Sergio Alexandre; Frugis, Victor Lourenço; Shibli, Jamil Awad; Fernandez, Maria Piedad Ramirez; Sánchez de Val, José Eduardo Maté; Girardo, José Luis Calvo; Taschieri, Silvio; Corbella, Stefano

    2016-01-01

    This study compared the influence of implant design (cylindrical and conical) in the load transfer on bone surrounding 13mm and 7mm length implants under simulated occlusal loading, using photoelastic analysis. Dental implants of 4mm diameter were divided into four groups, which varied in length and design: Group 1- standard (13 mm) cylindrical implant; Group 2 - standard conical implant; Group 3 - short (7 mm) cylindrical implant, and Group 4 - short conical implant. After the inclusion of the implant models in a photoelastic resin, they were subjected to a static load of 100 N. The lengths of the fringes that were generated were measured in three portions since the implants body: crestal, central and apical portion, parallel to the implant long axis. Furthermore, the entire extension area of dissipation of force was measured. Data were analyzed by one-way ANOVA (α = 0.05). Lower stress was observed at the crestal bone in groups 2 and 4, while the stress levels in groups 1 and 3 were higher with significant differences compared to the other groups (pimplant length under axial loading condition, but changed in relation to the implant design with respect to the concentration of the fringes, which corresponded to the load distribution, with even more dissipation by conical implants.

  6. Short implants (6mm) vs. vertical bone augmentation and standard-length implants (≥9mm) in atrophic posterior mandibles: a 5-year retrospective study.

    Science.gov (United States)

    Pieri, F; Forlivesi, C; Caselli, E; Corinaldesi, G

    2017-12-01

    This retrospective study compared the 5-year clinical and radiographic outcomes of short implants (6 mm) (short group), and standard-length implants (≥9mm) placed after a vertical augmentation with autologous bone blocks (augmentation group), supporting partial fixed prostheses in the posterior mandible. Forty-five partially edentulous patients were enrolled in the study and evaluated after 5 years: 22 (51 implants) in the augmentation group and 23 (46 implants) in the short group. Eight surgical complications occurred in the augmentation group versus none in the short group (P=0.003). One short implant failed before loading and one standard-length implant failed after 4 years because of peri-implantitis (P=1.0). Eight biological and two prosthetic complications occurred in the augmentation group vs. three biological and three prosthetic complications in the short group (P=0.09 and P=1.0, respectively). A mean marginal bone loss of 1.61±1.12mm in the augmentation group and 0.68±0.68mm in the short group was found (P=0.002). Within the limitations of this study, both techniques resulted in successful clinical results after 5 years, but short implants exhibited less surgical complications and marginal bone loss than standard-length implants placed in augmented bone. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. A lithographically patterned capacitor with horizontal nanowires of length 2.5 mm.

    Science.gov (United States)

    Yan, Wenbo; Thai, Mya Le; Dutta, Rajen; Li, Xiaowei; Xing, Wendong; Penner, Reginald M

    2014-04-09

    A symmetrical hybrid capacitor consisting of interdigitated, horizontal nanowires is described. Each of the 750 nanowires within the capacitor is 2.5 mm in length, consisting of a gold nanowire core (40 × ≈200 nm) encapsulated within a hemicylindrical shell of δ-phase MnO2 (thickness = 60-220 nm). These Au@δ-MnO2 nanowires are patterned onto a planar glass surface using lithographically patterned nanowire electrodeposition (LPNE). A power density of 165 kW/kg and energy density of 24 Wh/kg were obtained for a typical nanowire array in which the MnO2 shell thickness was 68 ± 8 nm. Capacitors incorporating these ultralong nanowires lost ≈10% of their capacity rapidly, during the first 20 discharge cycles, and then retained 90% of their maximum capacity for the ensuing 6000 cycles. The ability of capacitors consisting of ultralong Au@δ-MnO2 nanowires to simultaneously deliver high power and high capacity with acceptable cycle life is demonstrated.

  8. 4-mm-diameter three-dimensional imaging endoscope with steerable camera for minimally invasive surgery (3-D-MARVEL).

    Science.gov (United States)

    Bae, Sam Y; Korniski, Ronald J; Shearn, Michael; Manohara, Harish M; Shahinian, Hrayr

    2017-01-01

    High-resolution three-dimensional (3-D) imaging (stereo imaging) by endoscopes in minimally invasive surgery, especially in space-constrained applications such as brain surgery, is one of the most desired capabilities. Such capability exists at larger than 4-mm overall diameters. We report the development of a stereo imaging endoscope of 4-mm maximum diameter, called Multiangle, Rear-Viewing Endoscopic Tool (MARVEL) that uses a single-lens system with complementary multibandpass filter (CMBF) technology to achieve 3-D imaging. In addition, the system is endowed with the capability to pan from side-to-side over an angle of [Formula: see text], which is another unique aspect of MARVEL for such a class of endoscopes. The design and construction of a single-lens, CMBF aperture camera with integrated illumination to generate 3-D images, and the actuation mechanism built into it is summarized.

  9. Development and application of superconducting magnet for gyrotron with 4 mm wave length

    International Nuclear Information System (INIS)

    Zhu Xuewu; Pu Men; Chen Jian; Liu Jianmin; Shi Qingju

    1989-01-01

    A superconducting magnet for gyrotron with 4 mm wave legnth is developed, its main magnetic field reaches 3 T. The gyrotron combined with the magnet producesfundamental wave long pulse, its power is more than 60 kW, pulse duration 10 ∼ 20 ms, frequency 70 GHz. It is used for plasma preionization experiment on HL-1 Tokamak

  10. Construction experience with Fermilab-built full length 50mm SSC dipoles

    Energy Technology Data Exchange (ETDEWEB)

    Blessing, M.J.; Hoffman, D.E.; Packer, M.D. (General Dynamics Corp., San Diego, CA (United States). Space Systems Div.); Bossert, R.C.; Brandt, J.S.; Carson, J.A.; Delchamps, S.; Ewald, K.D.; Fulton, H.J.; Haggard, J.E.; Jensen, R.H.; Koska, W.; Rihel, R.K.; Robotham, W.F.; Smith, B.E.; Smith, D.J.; Strait, J.B.; Tassotto, G.; Tinsley, D.A.; Wake, M.; Winters, M.; Zimmerman, W.F. (Fermi National Accelerator Lab., Ba

    1992-03-01

    Fourteen full length SSC dipole magnets are being built and tested at Fermilab. Their purpose is to verify the magnet design as well as transfer the construction technology to industry. Magnet design is summarized. Construction problems and their solutions are discussed. Topics include coil winding, curing and measuring, collaring, instrumentation, end clamp installation, yoking and electrical and mechanical interconnection.

  11. Construction experience with Fermilab-built full length 50mm SSC dipoles

    International Nuclear Information System (INIS)

    Blessing, M.J.; Hoffman, D.E.; Packer, M.D.; Gordon, M.; Higinbotham, W.; Sims, R.

    1992-03-01

    Fourteen full length SSC dipole magnets are being built and tested at Fermilab. Their purpose is to verify the magnet design as well as transfer the construction technology to industry. Magnet design is summarized. Construction problems and their solutions are discussed. Topics include coil winding, curing and measuring, collaring, instrumentation, end clamp installation, yoking and electrical and mechanical interconnection

  12. Cochlear implantation in Mondini's deformity: could the straight electrode array with length of 31 mm be fully inserted?

    Science.gov (United States)

    Sun, Jia-Qiang; Sun, Jing-Wu; Hou, Xiao-Yan

    2017-07-01

    The straight electrode array with length of 31 mm can be fully inserted using round window insertion in cochlear implantation with Mondini's deformity. It is a safe and effective process, but also a challenging task of the full implantation in children with Mondini's deformity. The aim of this study is to discuss whether the straight electrode array with a length of 31 mm could be fully inserted in cochlear implantation with Mondini's deformity. A chart review of 30 patients undergoing cochlear implantation with Mondini's deformity using the electrode array with length of 31 mm was undertaken from January 2012 and December 2015 in Anhui Provincial Hospital. Full insertion of the straight electrode array with length of 31 mm were performed successfully in all patients with Mondini's deformity using round window insertion. Resistance was not encountered while introducing the electrodes. Ten of 30 patients had cerebrospinal fluid drainage during cochlear implantation. Cerebrospinal fluid drainage was controlled with small pieces of temporalis fascia packing round window in all patients. Intra-operative neural response telemetry was performed in all patients, and results were good. The result of X-ray showed proper placement of the cochlear implant electrode array. During surgery, no patients had experienced any immediate or delayed post-operative complications such as wound infection, intracranial complication, extrusion, or migration of the implant during an average follow-up period of 6-36 months.

  13. Magnetic field measurements of full length 50 mm aperture SSC dipole magnets at Fermilab

    International Nuclear Information System (INIS)

    Strait, J.; Bossert, R.; Carson, J.; Delchamps, S.W.; Gourlay, S.; Hanft, R.; Koska, W.; Kuchnir, M.; Lamm, M.J.; Mazur, P.O.; Mokhtarani, A.; Orris, D.; Ozelis, J.; Wake, M.; Devred, A.; DiMarco, J.; Kuzminski, J.; Puglisi, M.; Tompkins, J.C.; Yu, Y.; Zhao, Y.; Zheng, H.; Ogitsu, T.

    1992-09-01

    Thirteen 16 m long, 50 mm aperture SSC dipole magnets, designed jointly by Fermilab, Brookhaven National Laboratory, Lawrence Berkeley Laboratory and the SSC Laboratory, have been built at Fermilab. The first nine magnets have been fully tested to date. The allowed harmonics are systematically shifted from zero by amounts larger than the specification. The unallowed harmonics, with the exception of the skew sextupole, are consistent with zero. The magnet-to-magnet RMS variation of all harmonics is much smaller than the specification

  14. Do implant length and width matter for short dental implants (<10 mm)? A meta-analysis of prospective studies.

    Science.gov (United States)

    Monje, Alberto; Fu, Jia-Hui; Chan, Hsun-Liang; Suarez, Fernando; Galindo-Moreno, Pablo; Catena, Andrés; Wang, Hom-Lay

    2013-12-01

    This meta-analysis of prospective clinical trials was conducted to determine the effects of dental implant length and width on implant survival rate of short (implants. An electronic search of the PubMed database for relevant studies published in English from November 1998 to March 2012 was performed. Selected studies were randomized clinical trials, human clinical trials, or prospective trials with a clear aim of investigating the success or survival rate of short (implants. Eight studies fulfilled the inclusion criteria and were subsequently analyzed. A total of 525 short (implants were analyzed, of which 253 were 3.5 mm in diameter (48.19%), 151 were 4.0 mm (28.76%), 90 were 4.1 mm (17.14%), 21 were 4.8 mm (4%), and 10 were 5.1 mm (1.9%). All implants included in this meta-analysis had a follow-up period of 12 to 72 months. The included studies reported on the survival rate and diameter of the implants. Six of the studies used "short implants" (7 to 9 mm), and the remaining were classified as "extra-short implants" (≤ 6 mm). Five-year estimated failure rates were 1.61% and 2.92%, respectively, for extra-short and short implants (z = -3.49, P implant, the higher the failure rate (estimated failure rate = 2.36%, 95% confidence interval = 1.07% to 5.23%). Neither implant length nor width seemed to significantly affect the survival rate of short implants (<10 mm). Nonetheless, further well-designed randomized clinical trials are needed to confirm these findings.

  15. Test of Fermilab built 40 mm aperture full length SSC dipole magnets

    International Nuclear Information System (INIS)

    Koska, W.; Bleadon, M.; Bossert, R.; Carson, J.; Delchamps, S.; Gourlay, S.; Hanft, R.; Kuchnir, M.; Lamm, M.J.; Mantsch, P.

    1992-01-01

    Several 40 mm aperture, 17 m long dipoles have been built by Fermilab as developmental prototypes for the Superconducting Super Collider. These magnets differ from those manufactured at Brookhaven National Laboratory in that they have an external inner-outer coil splice design, a collet style end clamp assembly, a new, analytically designed minimum stress coil end design, and a new insulation system which does not employ shims or shoes. In addition, the magnets were built using production-style tooling. The magnets were tested at the Fermilab Magnet Testing Facility. In this paper quench testing and mechanical measurement results are presented and analyzed with emphasis on the design and fabrication features of these magnets

  16. Tests of Fermilab built 40 mm aperture full length SSC dipole magnets

    International Nuclear Information System (INIS)

    Koska, W.; Bleadon, M.; Bossert, R.; Carson, J.; Delchamps, S.; Gourlay, S.; Hanft, R.; Kuchnir, M.; Lamm, M.J.; Mantsch, P.; Mazur, P.O.; Orris, D.; Strait, J.; Wake, M.; Bush, T.; Coombes, R.; Devred, A.; DiMarco, J.; Goodzeit, C.; Kuzminski, J.; Ogitsu, T.; Puglisi, M.; Radusewicz, P.; Schermer, R.; Tompkins, J.C.; Wolf, Z.; Yu, Y.; Zheng, H.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A.; Greene, A.; Gupta, R.; Kahn, S.; Herrera, J.; Kelly, E.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E.P.; Sampson, W.; Shutt, R.; Thompson, P.; Wanderer, P.; Willen, E.; Royet, J.; Scanlan, R.; Taylor, C.

    1991-09-01

    Several 40 mm aperture, 17 m long dipoles have been built by Fermilab as developmental prototypes for the Superconducting Super Collider. These magnets differ from those manufactured at Brookhaven National Laboratory in that they have an external inner-outer coil splice design, a collet style end clamp assembly, a new, analytically designed minimum stress coil end design, and a new insulation system which does not employ shims or ''shoes''. In addition, the magnets were built using production-style tooling. The magnets were tested at the Fermilab Magnet Testing Facility. Quench testing and mechanical measurement results are presented and analyzed with emphasis on the new design and fabrication features of these magnets. 13 refs., 5 figs

  17. Test of Fermilab built, post-ASST, 50-mm-aperture, full length SSC dipole magnets

    International Nuclear Information System (INIS)

    Kuzminski, J.; Akhmetov, A.; Bossert, R.

    1993-05-01

    During 1992 at Fermilab, a series of nine 50-mm-aperture, 15-m-long, SSC superconducting dipole magnets, designed jointly by Fermilab, Brookhaven National Laboratory, and the SSC Laboratory, have been built and successfully cold tested. Seven of these dipole magnets, designate for the Accelerator System String Test (ASST) carried out at SSCL in Dallas, were assembled Fermilab by General Dynamics personnel, and have achieved the nominal operating current level without significant training. In addition, a series of four R ampersand D magnets (DCA320 323) we manufactured at Fermilab to test an alternative insulation schemes. In this paper we present th quench performance of these four R ampersand D magnets, which were cold tested at the Fermilab Magnet Test Facility at nominal temperatures of 4.35 K, 3.85 K, and 3.50 K. An extended characterization test was performed on one of these magnets (DCA322). During this test the magnet was successfully cooled down to superfluid He temperature (1.8 K) and reached a field B ≥ 9.5 T

  18. Surface-micromachined magnetic undulator with period length between 10μm and 1 mm for advanced light sources

    Science.gov (United States)

    Harrison, Jere; Joshi, Abhijeet; Lake, Jonathan; Candler, Rob; Musumeci, Pietro

    2012-07-01

    A technological gap exists between the μm-scale wiggling periods achieved using electromagnetic waves of high intensity laser pulses and the mm scale of permanent-magnet and superconducting undulators. In the sub-mm range, surface-micromachined soft-magnetic micro-electro-mechanical system inductors with integrated solenoidal coils have already experimentally demonstrated 100 to 500 mT field amplitude across air gaps as large as 15μm. Simulations indicate that magnetic fields as large as 1.5 T across 50μm inductor gaps are feasible. A simple rearranging of the yoke and pole geometry allows for fabrication of 10+ cm long undulator structures with period lengths between 12.5μm and 1 mm. Such undulators find application both in high average power spontaneous emission sources and, if used in combination with ultrahigh-brightness electron beams, could lead to the realization of low energy compact free-electron lasers. Challenges include electron energy broadening due to wakefields and Joule heating in the electromagnet.

  19. Windowing UWB microwave, mm-wave multi-port S-parameter measurements using open-ended excess electrical length

    Directory of Open Access Journals (Sweden)

    Gholamreza Askari

    2017-05-01

    Full Text Available Multi-port measurements are a big challenge in circuits' verification, especially when the frequency increases. This study presents a new technique for measuring S-parameters of multi-port ultra-wideband (UWB microwave and mm-wave circuits. The concepts are based on direct or indirect applying modulated UWB impulse radio in desired bandwidth to the one port of the modified multi-port circuit and gathering the reflected signal in the same port and the output signal in the second port in time domain, and the other ports are left opened with a special designed added electrical length. Then by applying intelligent windowing in time domain to the gathering data, and using fast Fourier transform, the desired S-parameters are extracted. Validation of this technique is verified by design and fabrication of a three-port UWB Wilkinson power divider in 22–30 GHz. The simulation and measurement results of the reflection and transmission S-parameters by using this new technique are very close to those are extracted with the conventional vector network analysers S-parameters measurements and show the ability and the accuracy of this technique.

  20. An evaluation of deep-sea benthic megafauna length measurements obtained with laser and stereo camera methods

    Science.gov (United States)

    Dunlop, Katherine M.; Kuhnz, Linda A.; Ruhl, Henry A.; Huffard, Christine L.; Caress, David W.; Henthorn, Richard G.; Hobson, Brett W.; McGill, Paul; Smith, Kenneth L.

    2015-02-01

    The 25 year time-series collected at Station M, ~4000 m on the Monterey Deep-sea Fan, has substantially improved understanding of the role of the deep-ocean benthic environment in the global carbon cycle. However, the role of deep-ocean benthic megafauna in carbon bioturbation, remineralization and sequestration is relatively unknown. It is important to gather both accurate and precise measurements of megafaunal community abundance, size distribution and biomass to further define their role in deep-sea carbon cycling and possible sequestration. This study describes initial results from a stereo camera system attached to a remotely operated vehicle and analyzed using the EventMeasure photogrammetric measurement software to estimate the density, length and biomass of 10 species of mobile epibenthic megafauna. Stereo length estimates were compared to those from a single video camera system equipped with sizing lasers and analyzed using the Monterey Bay Aquarium Research Institute's Video Annotation and Reference System. Both camera systems and software were capable of high measurement accuracy and precision (megafauna species studied. The stereo image analysis process took substantially longer than the video analysis and the value of the EventMeasure software tool would be improved with developments in analysis automation. The stereo system is less influenced by object orientation and height, and is potentially a useful tool to be mounted on an autonomous underwater vehicle and for measuring deep-sea pelagic animals where the use of lasers is not feasible.

  1. Surface-micromachined magnetic undulator with period length between 10  μm and 1 mm for advanced light sources

    Directory of Open Access Journals (Sweden)

    Jere Harrison

    2012-07-01

    Full Text Available A technological gap exists between the μm-scale wiggling periods achieved using electromagnetic waves of high intensity laser pulses and the mm scale of permanent-magnet and superconducting undulators. In the sub-mm range, surface-micromachined soft-magnetic micro-electro-mechanical system inductors with integrated solenoidal coils have already experimentally demonstrated 100 to 500 mT field amplitude across air gaps as large as 15  μm. Simulations indicate that magnetic fields as large as 1.5 T across 50  μm inductor gaps are feasible. A simple rearranging of the yoke and pole geometry allows for fabrication of 10+ cm long undulator structures with period lengths between 12.5  μm and 1 mm. Such undulators find application both in high average power spontaneous emission sources and, if used in combination with ultrahigh-brightness electron beams, could lead to the realization of low energy compact free-electron lasers. Challenges include electron energy broadening due to wakefields and Joule heating in the electromagnet.

  2. Accurate Bond Lengths to Hydrogen Atoms from Single-Crystal X-ray Diffraction by Including Estimated Hydrogen ADPs and Comparison to Neutron and QM/MM Benchmarks.

    Science.gov (United States)

    Dittrich, Birger; Lübben, Jens; Mebs, Stefan; Wagner, Armin; Luger, Peter; Flaig, Ralf

    2017-04-03

    Amino acid structures are an ideal test set for method-development studies in crystallography. High-resolution X-ray diffraction data for eight previously studied genetically encoding amino acids are provided, complemented by a non-standard amino acid. Structures were re-investigated to study a widely applicable treatment that permits accurate X-H bond lengths to hydrogen atoms to be obtained: this treatment combines refinement of positional hydrogen-atom parameters with aspherical scattering factors with constrained "TLS+INV" estimated hydrogen anisotropic displacement parameters (H-ADPs). Tabulated invariom scattering factors allow rapid modeling without further computations, and unconstrained Hirshfeld atom refinement provides a computationally demanding alternative when database entries are missing. Both should incorporate estimated H-ADPs, as free refinement frequently leads to over-parameterization and non-positive definite H-ADPs irrespective of the aspherical scattering model used. Using estimated H-ADPs, both methods yield accurate and precise X-H distances in best quantitative agreement with neutron diffraction data (available for five of the test-set molecules). This work thus solves the last remaining problem to obtain such results more frequently. Density functional theoretical QM/MM computations are able to play the role of an alternative benchmark to neutron diffraction. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Comparison of clinical and radiographic parameters around short (6 to 8 mm in length) and long (11 mm in length) dental implants placed in patients with and without type 2 diabetes mellitus: 3-year follow-up results.

    Science.gov (United States)

    Al Amri, Mohammad D; Abduljabbar, Tariq S; Al-Johany, Sulieman S; Al Rifaiy, Mohammad Q; Alfarraj Aldosari, Abdullah M; Al-Kheraif, Abdulaziz A

    2017-10-01

    To compare the clinical and radiographic parameters around short (6 to 8 mm in length) and long (11 mm in length) dental implants placed in patients with and without type 2 diabetes mellitus (T2DM). Forty-five male patients with T2DM (Group-1) and 42 male non-diabetic controls (Group-2) who had undergone implant therapy in the posterior mandible were included. Depending upon the length of the implant, patients were divided into two subgroups: (a) patients with short implants (6-8 mm long) and (b) patients with long implants (11 mm long). Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD) and crestal bone loss (CBL) were measured at 18 and 36 months of follow-up in both groups. Hemoglobin A1c (HbA1c) levels were measured at baseline and after 18 and 36 months of follow-up in both groups. P-values less than 0.05 were considered statistically significant. The mean age of patients in groups 1 and 2 was 42.5 and 40.6 years, respectively. The mean HbA1c levels at baseline among patients in groups 1 and 2 were 7.7% and 4.5%, respectively. At 18 and 36 months of follow-up, the mean HbA1c levels among patients in groups 1 and 2 were 6.6% and 4.5% and 6.5% and 4.4%, respectively. The mean duration of T2DM among patients that received short and long implants was 4.3 years and 4.1 years, respectively. There was no significant difference in PI, BOP, PD and CBL around implants placed in both groups at 18 and 36 months of follow-up. Success rate of short and long dental implants was 100% in both groups. Short implants can demonstrate clinical and radiographic stability in a manner similar to conventional long implants in patients with and without T2DM. The role of oral hygiene and glycemic maintenance in this scenario cannot be disregarded. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Effect of plate working length on plate stiffness and cyclic fatigue life in a cadaveric femoral fracture gap model stabilized with a 12-hole 2.4 mm locking compression plate.

    Science.gov (United States)

    Chao, Peini; Conrad, Bryan P; Lewis, Daniel D; Horodyski, MaryBeth; Pozzi, Antonio

    2013-06-24

    There are several factors that can affect the fatigue life of a bone plate, including the mechanical properties of the plate and the complexity of the fracture. The position of the screws can influence construct stiffness, plate strain and cyclic fatigue of the implants. Studies have not investigated these variables in implants utilized for long bone fracture fixation in dogs and cats. The purpose of the present study was to evaluate the effect of plate working length on construct stiffness, gap motion and resistance to cyclic fatigue of dog femora with a simulated fracture gap stabilized using a 12-hole 2.4 mm locking compression plates (LCP). Femora were plated with 12-hole 2.4 mm LCP using 2 screws per fracture segment (long working length group) or with 12-hole 2.4 mm LCP using 5 screws per fracture segment (a short working length group). Construct stiffness did not differ significantly between stabilization techniques. Implant failure did not occur in any of the plated femora during cycling. Mean ± SD yield load at failure in the short plate working length group was significantly higher than in the long plate working length group. In a femoral fracture gap model stabilized with a 2.4 mm LCP applied in contact with the bone, plate working length had no effect on stiffness, gap motion and resistance to fatigue. The short plate working length constructs failed at higher loads; however, yield loads for both the short and long plate working length constructs were within physiologic range.

  5. Cold mass mechanical design, quench and mechanical test results for full length 50 mm aperture SSC model dipoles built at BNL

    International Nuclear Information System (INIS)

    Goodzeit, C.; Radusewicz, P.; Anerella, M.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A.; Greene, A.; Gupta, R.; Jain, A.; Kahn, S.; Kelly, E.; Morgan, G.; Muratore, J.; Prodell, A.; Rehak, M.; Rohrer, E.P.; Sampson, W.; Shutt, R.; Thomas, R.; Thompson, P.; Wanderer, P.; Willen, E.

    1992-07-01

    A series of seven 50 mm aperture, 15-meter long dipole magnets was built and assembled at Brookhaven National Laboratory (BNL). Their design embodies features for evaluation for the final selection of the design for the SSC Collider dipole magnets. This paper discusses mechanical design of the cold mass and presents test results such as quench histories and mechanical parameters during construction and testing

  6. Success and Failure Rates of 1,344 6- to 9-mm-Length Rough-Surface Implants Placed at the Time of Transalveolar Sinus Elevations, Restored with Single Crowns, and Followed for 60 to 229 Months in Function.

    Science.gov (United States)

    Fugazzotto, Paul A

    To assess the success and stability of 6-, 7-, 8-, and 9-mm-long, 6.5-mm-wide-neck tissue-level implants placed at the time of transalveolar sinus augmentation therapy, utilizing a trephine and osteotome approach, which were restored with single crowns. In total, 1,344 implants were placed by the author, varying in length from 6 to 9 mm, with parallel-wall 4.8-mm-diameter implant bodies and 6.5-mm-diameter implant necks. The implants were restored with single abutments and crowns by a variety of practitioners. They were followed for 60 to 229 months in function, with a mean time of 121.1 months in function. Implant success was evaluated by the author utilizing a combination of the Albrektsson et al criteria, and buccal and palatal/lingual bone sounding under anesthesia. The overall cumulative success rate was 98.8%. One hundred ninety 6-mm-long implants demonstrated a cumulative success rate of 97.5% at a mean time of 109.2 months in function. Eleven 7-mm-long implants demonstrated a cumulative success rate of 100% at a mean time of 218.5 months in function. One thousand ninety-four 8-mm-long implants demonstrated a cumulative success rate of 98.9% at a mean time of 112.3 months in function. Forty-nine 9-mm-long implants demonstrated a cumulative success rate of 100% at a mean time of 212.1 months in function. Implants of 6 to 9 mm in length, placed at the time of trephine and osteotome transalveolar sinus elevation procedures and restored with abutments and single crowns, demonstrate a high level of long-term clinical success, assuming specific comprehensive treatment criteria are met.

  7. Accurate Bond Lengths to Hydrogen Atoms from Single?Crystal X?ray Diffraction by Including Estimated Hydrogen ADPs and Comparison to Neutron and QM/MM Benchmarks

    OpenAIRE

    Dittrich, Birger; L?bben, Jens; Mebs, Stefan; Wagner, Armin; Luger, Peter; Flaig, Ralf

    2017-01-01

    Abstract Amino acid structures are an ideal test set for method?development studies in crystallography. High?resolution X?ray diffraction data for eight previously studied genetically encoding amino acids are provided, complemented by a non?standard amino acid. Structures were re?investigated to study a widely applicable treatment that permits accurate X?H bond lengths to hydrogen atoms to be obtained: this treatment combines refinement of positional hydrogen?atom parameters with aspherical s...

  8. The 3DBiopsy Prostate Biopsy System: Preclinical Investigation of a Needle, Actuator, and Specimen Collection Device Allowing Sampling of Individualized Prostate Lengths Between 20 and 60 mm.

    Science.gov (United States)

    Stone, Nelson N; Mouraviev, Vladimir; Schechter, David; Lucia, M Scott; Smith, Elizabeth E; Arangua, Paul; Hoenemeyer, John; Rosa, Jim; Bawa, Rajan; Crawford, E David

    2017-09-01

    To increase the likelihood of detecting anterior cancers within the prostate and provide a specimen that spans the length of the gland. Newly designed 17- and 15-gauge (G) biopsy needles, a variable actuator, and an integrated pathology system intended for the longer cores were developed and tested for this purpose. Testing was performed comparing 2 common cannula tip grinds, a Vet-point (sharp tip) and a Menghini-point (atraumatic tip), and were tested against 18-G Bard Monopty in porcine kidney. A variable actuator was developed to fire the needle 20-60 mm and tested in cadaver prostates. The aggregate firings for 3 different shot lengths comparing the Vet- with the Menghini-tip cannulas demonstrated 91% vs 85.2% fill (length of specimen/length of core bed, P = .007). A 15-G trocar needle with the Vet-tip cannula also had the best performance, with an aggregate standard deviation of 6.4% across 3 firing ranges and a minimum to maximum specimen length of 81%-105% of potential fill. Cadaver testing with the Vet-tip needles in the actuator for the transrectal (17-G) and transperineal (15-G) biopsies demonstrated mean fills of 93.3% and 76.5%, respectively. The new transrectal ultrasound needle obtained a 2-fold increase in specimen length over the standard Bard device (P planning. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Clinical Effectiveness of 6.5-mm-Long Implants to Support Two-Implant Fixed Prostheses in Premolar-Molar Region: The Influence of Immediate Loading and the Length of Splinting Implant.

    Science.gov (United States)

    Anitua, Eduardo; Flores, Carlos; Flores, Javier; Alkhraisat, Mohammad Hamdan

    2018-01-28

    The purpose of this retrospective clinical study was to assess the influence of immediate loading and lengths of splinted implants on the clinical effectiveness of 6.5-mm-long implants supporting two-implant fixed prostheses in the premolar-molar regions. A clinical database was reviewed in a private dental center to select those patients who had 6.5-mm-long implants placed to support two-implant fixed partial prostheses in the premolar-molar regions of the maxilla and the mandible. All implants were immediately loaded. The study groups were defined according to the lengths of the implants. Two groups were identified: the short-short splinted group, when both implants had 6.5 mm lengths, and the short-long splinted group, when one implant was longer than 6.5 mm. A total of 48 dental implants were placed in 16 patients to support 24 two-implant fixed prostheses. The mean follow-up time was 14 ± 5 months. The short-short splinted group included 8 patients with 16 implants; the short-long splinted group included 16 patients with 32 implants. The main variable was implant survival, and secondary outcomes were marginal bone stability and prosthesis survival. The statistical analyses indicated an absence of significant differences between the two groups in terms of implant and prosthesis survival (100% for both groups and both variables); however, distal bone loss around the splinted implants was significantly higher in the short-long splinted group. Bone loss was 0.37 ± 0.55 mm in the short-short splinted group and 0.94 ± 0.66 mm in the short-long splinted group. Immediate loading of short (6.5-mm-long) implants in the premolar-molar regions did not jeopardize their survival. Two-implant supported prostheses had the same clinical effectiveness, whether extra-short implants were splinted to another extra-short implant or to a longer one. © 2018 by the American College of Prosthodontists.

  10. PERFORMANCE EVALUATION OF THERMOGRAPHIC CAMERAS FOR PHOTOGRAMMETRIC MEASUREMENTS

    Directory of Open Access Journals (Sweden)

    N. Yastikli

    2013-05-01

    Full Text Available The aim of this research is the performance evaluation of the termographic cameras for possible use for photogrammetric documentation and deformation analyses caused by moisture and isolation problem of the historical and cultural heritage. To perform geometric calibration of the termographic camera, the 3D test object was designed with 77 control points which were distributed in different depths. For performance evaluation, Flir A320 termographic camera with 320 × 240 pixels and lens with 18 mm focal length was used. The Nikon D3X SLR digital camera with 6048 × 4032 pixels and lens with 20 mm focal length was used as reference for comparison. The size of pixel was 25 μm for the Flir A320 termographic camera and 6 μm for the Nikon D3X SLR digital camera. The digital images of the 3D test object were recorded with the Flir A320 termographic camera and Nikon D3X SLR digital camera and the image coordinate of the control points in the images were measured. The geometric calibration parameters, including the focal length, position of principal points, radial and tangential distortions were determined with introduced additional parameters in bundle block adjustments. The measurement of image coordinates and bundle block adjustments with additional parameters were performed using the PHIDIAS digital photogrammetric system. The bundle block adjustment was repeated with determined calibration parameter for both Flir A320 termographic camera and Nikon D3X SLR digital camera. The obtained standard deviation of measured image coordinates was 9.6 μm and 10.5 μm for Flir A320 termographic camera and 8.3 μm and 7.7 μm for Nikon D3X SLR digital camera. The obtained standard deviation of measured image points in Flir A320 termographic camera images almost same accuracy level with digital camera in comparison with 4 times bigger pixel size. The obtained results from this research, the interior geometry of the termographic cameras and lens distortion was

  11. Performance Evaluation of Thermographic Cameras for Photogrammetric Measurements

    Science.gov (United States)

    Yastikli, N.; Guler, E.

    2013-05-01

    The aim of this research is the performance evaluation of the termographic cameras for possible use for photogrammetric documentation and deformation analyses caused by moisture and isolation problem of the historical and cultural heritage. To perform geometric calibration of the termographic camera, the 3D test object was designed with 77 control points which were distributed in different depths. For performance evaluation, Flir A320 termographic camera with 320 × 240 pixels and lens with 18 mm focal length was used. The Nikon D3X SLR digital camera with 6048 × 4032 pixels and lens with 20 mm focal length was used as reference for comparison. The size of pixel was 25 μm for the Flir A320 termographic camera and 6 μm for the Nikon D3X SLR digital camera. The digital images of the 3D test object were recorded with the Flir A320 termographic camera and Nikon D3X SLR digital camera and the image coordinate of the control points in the images were measured. The geometric calibration parameters, including the focal length, position of principal points, radial and tangential distortions were determined with introduced additional parameters in bundle block adjustments. The measurement of image coordinates and bundle block adjustments with additional parameters were performed using the PHIDIAS digital photogrammetric system. The bundle block adjustment was repeated with determined calibration parameter for both Flir A320 termographic camera and Nikon D3X SLR digital camera. The obtained standard deviation of measured image coordinates was 9.6 μm and 10.5 μm for Flir A320 termographic camera and 8.3 μm and 7.7 μm for Nikon D3X SLR digital camera. The obtained standard deviation of measured image points in Flir A320 termographic camera images almost same accuracy level with digital camera in comparison with 4 times bigger pixel size. The obtained results from this research, the interior geometry of the termographic cameras and lens distortion was modelled efficiently

  12. Comparison of peri-implant clinical and radiographic status around short (6 mm in length) dental implants placed in cigarette-smokers and never-smokers: Six-year follow-up results.

    Science.gov (United States)

    Abduljabbar, Tariq; Al-Hamoudi, Nawwaf; Al-Sowygh, Zeyad H; Alajmi, Mohammed; Javed, Fawad; Vohra, Fahim

    2018-02-01

    It is hypothesized that peri-implant clinical and radiographic inflammatory parameters (probing depth [PD], bleeding on probing [BOP] and plaque index [PI]; and radiographic (crestal bone loss [CBL]) are worse among cigarette-smokers (CS) compared with never-smokers (NS) with short implants. The present 6-year follow-up retrospective study compared the peri-implant clinical and radiographic parameters in CS and NS with short dental implants (6 mm in length). Fifty-six male individuals were included. These individuals divided into 2 groups as follows: (a) Group-1: 29 self-reported systemically healthy CS with 48 short-implants; and (b) Group-2: 27 self-reported systemically healthy NS with 43 short implants. Peri-implant PD, PI, BOP, and CBL were measured. Group comparisons were done using the Kruskal-Wallis test and sample size was estimated. Level of significance was set at P values implant PD, BOP, PI, and mesial and distal CBL were comparable around short implants in both groups. Under strict oral hygiene maintenance protocols, short dental implants can remain functionally stable in CS in a manner similar to NS. © 2017 Wiley Periodicals, Inc.

  13. Photographic zoom fisheye lens design for DSLR cameras

    Science.gov (United States)

    Yan, Yufeng; Sasian, Jose

    2017-09-01

    Photographic fisheye lenses with fixed focal length for cameras with different sensor formats have been well developed for decades. However, photographic fisheye lenses with variable focal length are rare on the market due in part to the greater design difficulty. This paper presents a large aperture zoom fisheye lens for DSLR cameras that produces both circular and diagonal fisheye imaging for 35-mm sensors and diagonal fisheye imaging for APS-C sensors. The history and optical characteristics of fisheye lenses are briefly reviewed. Then, a 9.2- to 16.1-mm F/2.8 to F/3.5 zoom fisheye lens design is presented, including the design approach and aberration control. Image quality and tolerance performance analysis for this lens are also presented.

  14. Gamma camera

    International Nuclear Information System (INIS)

    Tschunt, E.; Platz, W.; Baer, Ul; Heinz, L.

    1978-01-01

    A gamma camera has a plurality of exchangeable collimators, one of which is replaceably mounted in the ray inlet opening of the camera, while the others are placed on separate supports. Supports are swingably mounted upon a column one above the other

  15. Gamma camera

    International Nuclear Information System (INIS)

    Schlosser, P.A.; Steidley, J.W.

    1980-01-01

    The design of a collimation system for a gamma camera for use in nuclear medicine is described. When used with a 2-dimensional position sensitive radiation detector, the novel system can produce superior images than conventional cameras. The optimal thickness and positions of the collimators are derived mathematically. (U.K.)

  16. Gamma camera

    International Nuclear Information System (INIS)

    Tschunt, E.; Platz, W.; Baer, U.; Heinz, L.

    1978-01-01

    A gamma camera has a plurality of exchangeable collimators, one of which is mounted in the ray inlet opening of the camera, while the others are placed on separate supports. The supports are swingably mounted upon a column one above the other through about 90 0 to a collimator exchange position. Each of the separate supports is swingable to a vertically aligned position, with limiting of the swinging movement and positioning of the support at the desired exchange position. The collimators are carried on the supports by means of a series of vertically disposed coil springs. Projections on the camera are movable from above into grooves of the collimator at the exchange position, whereupon the collimator is turned so that it is securely prevented from falling out of the camera head

  17. Effect of plate working length on plate stiffness and cyclic fatigue life in a cadaveric femoral fracture gap model stabilized with a 12-hole 2.4?mm locking compression plate

    OpenAIRE

    Chao, Peini; Conrad, Bryan P; Lewis, Daniel D; Horodyski, MaryBeth; Pozzi, Antonio

    2013-01-01

    Background There are several factors that can affect the fatigue life of a bone plate, including the mechanical properties of the plate and the complexity of the fracture. The position of the screws can influence construct stiffness, plate strain and cyclic fatigue of the implants. Studies have not investigated these variables in implants utilized for long bone fracture fixation in dogs and cats. The purpose of the present study was to evaluate the effect of plate working length on construct ...

  18. Ultra-miniature catadioptrical system for an omnidirectional camera

    Science.gov (United States)

    Gimkiewicz, C.; Urban, C.; Innerhofer, E.; Ferrat, P.; Neukom, S.; Vanstraelen, G.; Seitz, P.

    2008-04-01

    The restricted field of view of traditional camera technology is increasingly limiting in many relevant applications such as security, surveillance, automotive, robotics, autonomous navigation or domotics. Omnidirectional cameras with their horizontal field of view of 360° would be ideal devices for these applications if they were small, cost-effective, robust and lightweight. Conventional catadioptric system designs require mirror diameters and optical path lengths of several centimeters, often leading to solutions that are too large and too heavy to be practical. We are presenting a novel optical design for an ultra-miniature camera that is so small and lightweight that it can be used as a key navigation aid for an autonomous flying micro-robot. The catadioptrical system consists of two components with a field-stop in-between: the first subsystem consists of a reflecting mirror and two refracting lens surfaces, and the second subsystem contains the imaging lens with two refractive surfaces. The field of view is 10°(upward) and 35°(downward). A field stop diameter of 1 mm and a back focal length of 2.3 mm have been achieved. For low-cost mass fabrication, the lens designs are optimised for production by injection moulding. Measurements of the first omnidirectional lens prototypes with a high-resolution imager show a performance close to the simulated values concerning spot size and image formation. The total weight of the optics is only 2 g including all mechanical mounts. The system's outer dimensions are 14.4 mm in height, with a 11.4 mm × 11.4 mm foot print, including the image sensor and its casing.

  19. Gamma camera

    International Nuclear Information System (INIS)

    Reiss, K.H.; Kotschak, O.; Conrad, B.

    1976-01-01

    A gamma camera with a simplified setup as compared with the state of engineering is described permitting, apart from good localization, also energy discrimination. Behind the usual vacuum image amplifier a multiwire proportional chamber filled with trifluorine bromium methane is connected in series. Localizing of the signals is achieved by a delay line, energy determination by means of a pulse height discriminator. With the aid of drawings and circuit diagrams, the setup and mode of operation are explained. (ORU) [de

  20. DEVELOPMENT OF CAMERA MODEL AND GEOMETRIC CALIBRATION/VALIDATION OF XSAT IRIS IMAGERY

    Directory of Open Access Journals (Sweden)

    L. K. Kwoh

    2012-07-01

    Full Text Available XSAT, launched on 20 April 2011, is the first micro-satellite designed and built in Singapore. It orbits the Earth at altitude of 822 km in a sun synchronous orbit. The satellite carries a multispectral camera IRIS with three spectral bands – 0.52~0.60 mm for Green, 0.63~0.69 mm for Red and 0.76~0.89 mm for NIR at 12 m resolution. In the design of IRIS camera, the three bands were acquired by three lines of CCDs (NIR, Red and Green. These CCDs were physically separated in the focal plane and their first pixels not absolutely aligned. The micro-satellite platform was also not stable enough to allow for co-registration of the 3 bands with simple linear transformation. In the camera model developed, this platform stability was compensated with 3rd to 4th order polynomials for the satellite's roll, pitch and yaw attitude angles. With the camera model, the camera parameters such as the band to band separations, the alignment of the CCDs relative to each other, as well as the focal length of the camera can be validated or calibrated. The results of calibration with more than 20 images showed that the band to band along-track separation agreed well with the pre-flight values provided by the vendor (0.093° and 0.046° for the NIR vs red and for green vs red CCDs respectively. The cross-track alignments were 0.05 pixel and 5.9 pixel for the NIR vs red and green vs red CCDs respectively. The focal length was found to be shorter by about 0.8%. This was attributed to the lower operating temperature which XSAT is currently operating. With the calibrated parameters and the camera model, a geometric level 1 multispectral image with RPCs can be generated and if required, orthorectified imagery can also be produced.

  1. Gamma camera

    International Nuclear Information System (INIS)

    Berninger, W.H.

    1975-01-01

    The light pulse output of a scintillator, on which incident collimated gamma rays impinge, is detected by an array of photoelectric tubes each having a convexly curved photocathode disposed in close proximity to the scintillator. Electronic circuitry connected to outputs of the phototubes develops the scintillation event position coordinate electrical signals with good linearity and with substantial independence of the spacing between the scintillator and photocathodes so that the phototubes can be positioned as close to the scintillator as is possible to obtain less distortion in the field of view and improved spatial resolution as compared to conventional planar photocathode gamma cameras

  2. 'Length'at Length

    Indian Academy of Sciences (India)

    Admin

    He was interested to know how `large' is the set of numbers x for which the series is convergent. Here large refers to its length. But his set is not in the class ♢. Here is another problem discussed by Borel. Consider .... have an infinite collection of pairs of new shoes and want to choose one shoe from each pair. We have an ...

  3. A versatile photogrammetric camera automatic calibration suite for multi-spectral fusion and optical helmet tracking

    CSIR Research Space (South Africa)

    De Villiers, J

    2014-05-01

    Full Text Available This paper presents a system to determine the photogrammetric parameters of a camera. The lens distortion, focal length and camera six degree of freedom (DOF) position are calculated. The system caters for cameras of different sensitivity spectra...

  4. Imaging of 1.0-mm-diameter radiopaque markers with megavoltage X-rays: an improved online imaging system

    International Nuclear Information System (INIS)

    Pang, G.; Beachey, D.J.; O'Brien, P.F.; Rowlands, J.A.

    2002-01-01

    Purpose: To improve an online portal imaging system such that implanted cylindrical gold markers of small diameter (no more than 1.0 mm) can be visualized. These small markers would make the implantation procedure much less traumatic for the patient than the large markers (1.6 mm in diameter), which are usually used today to monitor prostate interfraction motion during radiation therapy. Methods and Materials: Several changes have been made to a mirror-video based online imaging system to improve image quality. First, the conventional camera tube was replaced by an avalanche-multiplication-based video tube. This new camera tube has very high gain at the target such that the camera noise, which is one of the main causes of image degradation of online portal imaging systems, was overcome and effectively eliminated. Second, the conventional linear-accelerator (linac) target was replaced with a low atomic number (low-Z) target such that more diagnostic X-rays are present in the megavoltage X-ray beam. Third, the copper plate buildup layer for the phosphor screen was replaced by a thin plastic layer for detection of the diagnostic X-ray components in the beam generated by the low-Z target. Results: Radiopaque fiducial gold markers of different sizes, i.e., 1.0 mm (diameter) x 5 mm (length) and 0.8 mm (diameter) x 3 mm (length), embedded in an Alderson Rando phantom, can be clearly seen on the images acquired with our improved system. These markers could not be seen on images obtained with any commercial system available in our clinic. Conclusion: This work demonstrates the visibility of small-diameter radiopaque markers with an improved online portal imaging system. These markers can be easily implanted into the prostate and used to monitor the interfraction motion of the prostate

  5. Assessing the Potential of Low-Cost 3D Cameras for the Rapid Measurement of Plant Woody Structure

    Directory of Open Access Journals (Sweden)

    Charles Nock

    2013-11-01

    Full Text Available Detailed 3D plant architectural data have numerous applications in plant science, but many existing approaches for 3D data collection are time-consuming and/or require costly equipment. Recently, there has been rapid growth in the availability of low-cost, 3D cameras and related open source software applications. 3D cameras may provide measurements of key components of plant architecture such as stem diameters and lengths, however, few tests of 3D cameras for the measurement of plant architecture have been conducted. Here, we measured Salix branch segments ranging from 2–13 mm in diameter with an Asus Xtion camera to quantify the limits and accuracy of branch diameter measurement with a 3D camera. By scanning at a variety of distances we also quantified the effect of scanning distance. In addition, we also test the sensitivity of the program KinFu for continuous 3D object scanning and modeling as well as other similar software to accurately record stem diameters and capture plant form (<3 m in height. Given its ability to accurately capture the diameter of branches >6 mm, Asus Xtion may provide a novel method for the collection of 3D data on the branching architecture of woody plants. Improvements in camera measurement accuracy and available software are likely to further improve the utility of 3D cameras for plant sciences in the future.

  6. Assessing the potential of low-cost 3D cameras for the rapid measurement of plant woody structure.

    Science.gov (United States)

    Nock, Charles A; Taugourdeau, Olivier; Delagrange, Sylvain; Messier, Christian

    2013-11-27

    Detailed 3D plant architectural data have numerous applications in plant science, but many existing approaches for 3D data collection are time-consuming and/or require costly equipment. Recently, there has been rapid growth in the availability of low-cost, 3D cameras and related open source software applications. 3D cameras may provide measurements of key components of plant architecture such as stem diameters and lengths, however, few tests of 3D cameras for the measurement of plant architecture have been conducted. Here, we measured Salix branch segments ranging from 2-13 mm in diameter with an Asus Xtion camera to quantify the limits and accuracy of branch diameter measurement with a 3D camera. By scanning at a variety of distances we also quantified the effect of scanning distance. In addition, we also test the sensitivity of the program KinFu for continuous 3D object scanning and modeling as well as other similar software to accurately record stem diameters and capture plant form (6 mm, Asus Xtion may provide a novel method for the collection of 3D data on the branching architecture of woody plants. Improvements in camera measurement accuracy and available software are likely to further improve the utility of 3D cameras for plant sciences in the future.

  7. 29 mm Diameter Target Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Woloshun, Keith Albert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Olivas, Eric Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dale, Gregory E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Angela Carol [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Romero, Frank Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-10-23

    After numerous delays, the test of the 29 mm diameter target was conducted on 8/18/2017. The complete target design report, dated 8/15/2016, is reproduced below for completeness. This describes in detail the 10 disk target with varying thickness disks. The report presents and discusses the test results. In brief summary, there appears to have been multiple instrumentation errors. Measured temperatures, pressures and IR camera window temperature measurement are all suspect. All tests were done at 35 MeV, with 171 μA current, or 6 kW of beam power.

  8. Positron emission tomography camera

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    A positron emission tomography camera having a plurality of detector planes positioned side-by-side around a patient area to detect radiation. Each plane includes a plurality of photomultiplier tubes and at least two rows of scintillation crystals on each photomultiplier tube extend across to adjacent photomultiplier tubes for detecting radiation from the patient area. Each row of crystals on each photomultiplier tube is offset from the other rows of crystals, and the area of each crystal on each tube in each row is different than the area of the crystals on the tube in other rows for detecting which crystal is actuated and allowing the detector to detect more inter-plane slides. The crystals are offset by an amount equal to the length of the crystal divided by the number of rows. The rows of crystals on opposite sides of the patient may be rotated 90 degrees relative to each other

  9. Graphic design of pinhole cameras

    Science.gov (United States)

    Edwards, H. B.; Chu, W. P.

    1979-01-01

    The paper describes a graphic technique for the analysis and optimization of pinhole size and focal length. The technique is based on the use of the transfer function of optical elements described by Scott (1959) to construct the transfer function of a circular pinhole camera. This transfer function is the response of a component or system to a pattern of lines having a sinusoidally varying radiance at varying spatial frequencies. Some specific examples of graphic design are presented.

  10. Focal Length Affects Depicted Shape and Perception of Facial Images.

    Directory of Open Access Journals (Sweden)

    Vít Třebický

    Full Text Available Static photographs are currently the most often employed stimuli in research on social perception. The method of photograph acquisition might affect the depicted subject's facial appearance and thus also the impression of such stimuli. An important factor influencing the resulting photograph is focal length, as different focal lengths produce various levels of image distortion. Here we tested whether different focal lengths (50, 85, 105 mm affect depicted shape and perception of female and male faces. We collected three portrait photographs of 45 (22 females, 23 males participants under standardized conditions and camera setting varying only in the focal length. Subsequently, the three photographs from each individual were shown on screen in a randomized order using a 3-alternative forced-choice paradigm. The images were judged for attractiveness, dominance, and femininity/masculinity by 369 raters (193 females, 176 males. Facial width-to-height ratio (fWHR was measured from each photograph and overall facial shape was analysed employing geometric morphometric methods (GMM. Our results showed that photographs taken with 50 mm focal length were rated as significantly less feminine/masculine, attractive, and dominant compared to the images taken with longer focal lengths. Further, shorter focal lengths produced faces with smaller fWHR. Subsequent GMM revealed focal length significantly affected overall facial shape of the photographed subjects. Thus methodology of photograph acquisition, focal length in this case, can significantly affect results of studies using photographic stimuli perhaps due to different levels of perspective distortion that influence shapes and proportions of morphological traits.

  11. Mechanical analysis on magnesium alloy rotating mirror for ultra-high-speed camera

    Science.gov (United States)

    Li, Chunbo; Liu, Minqiu; Ren, Xikui; Du, Chenlin; Huang, Hongbin; Ruan, Shuangchen

    2018-03-01

    Rotating mirror is not only as an imaging element in optical path of ultra-high speed camera, where imaging quality is affected by surface quality and plane deformation of the rotating mirror, but also as an element to implement ultra-high speed, because performances of the ultra-high-speed camera system are mainly dependent on the static and dynamic mechanical properties of the rotating mirror. In this paper, the static and dynamic properties of magnesium alloy rotating mirror with equilateral-triangle cross-sections were investigated by theoretically and numerically method. At the speed of 2×105 rpm, the maximum lateral deformations of the mirror facet with width 17.32 mm and length 40 mm is 2.476 μm. The maximum von Mises stress is 35.1 MPa. The deformation and stress are less than that of aluminum alloy rotating mirror, which has been successfully applied in many types of RM for ultra-high speed cameras. The first three frequencies of magnesium alloy rotating mirror are 9,539.9 Hz, 9,540.9 Hz and 12,726.0 Hz, respectively. While the first three frequencies of aluminium alloy rotating-mirror are 9,683.9 Hz, 9,685.2 Hz and 11,016.0 Hz. From which it is preliminarily shown that a magnesium alloy rotating mirror can be used as replacement for an aluminium alloy rotating mirror in ultra-high-speed camera.

  12. Sub-Camera Calibration of a Penta-Camera

    Science.gov (United States)

    Jacobsen, K.; Gerke, M.

    2016-03-01

    cameras of both blocks have the same trend, but as usual for block adjustments with self calibration, they still show significant differences. Based on the very high number of image points the remaining image residuals can be safely determined by overlaying and averaging the image residuals corresponding to their image coordinates. The size of the systematic image errors, not covered by the used additional parameters, is in the range of a square mean of 0.1 pixels corresponding to 0.6μm. They are not the same for both blocks, but show some similarities for corresponding cameras. In general the bundle block adjustment with a satisfying set of additional parameters, checked by remaining systematic errors, is required for use of the whole geometric potential of the penta camera. Especially for object points on facades, often only in two images and taken with a limited base length, the correct handling of systematic image errors is important. At least in the analyzed data sets the self calibration of sub-cameras by bundle block adjustment suffers from the correlation of the inner to the exterior calibration due to missing crossing flight directions. As usual, the systematic image errors differ from block to block even without the influence of the correlation to the exterior orientation.

  13. SUB-CAMERA CALIBRATION OF A PENTA-CAMERA

    Directory of Open Access Journals (Sweden)

    K. Jacobsen

    2016-03-01

    for corresponding cameras of both blocks have the same trend, but as usual for block adjustments with self calibration, they still show significant differences. Based on the very high number of image points the remaining image residuals can be safely determined by overlaying and averaging the image residuals corresponding to their image coordinates. The size of the systematic image errors, not covered by the used additional parameters, is in the range of a square mean of 0.1 pixels corresponding to 0.6μm. They are not the same for both blocks, but show some similarities for corresponding cameras. In general the bundle block adjustment with a satisfying set of additional parameters, checked by remaining systematic errors, is required for use of the whole geometric potential of the penta camera. Especially for object points on facades, often only in two images and taken with a limited base length, the correct handling of systematic image errors is important. At least in the analyzed data sets the self calibration of sub-cameras by bundle block adjustment suffers from the correlation of the inner to the exterior calibration due to missing crossing flight directions. As usual, the systematic image errors differ from block to block even without the influence of the correlation to the exterior orientation.

  14. Those Nifty Digital Cameras!

    Science.gov (United States)

    Ekhaml, Leticia

    1996-01-01

    Describes digital photography--an electronic imaging technology that merges computer capabilities with traditional photography--and its uses in education. Discusses how a filmless camera works, types of filmless cameras, advantages and disadvantages, and educational applications of the consumer digital cameras. (AEF)

  15. Adapting Virtual Camera Behaviour

    DEFF Research Database (Denmark)

    Burelli, Paolo

    2013-01-01

    In a three-dimensional virtual environment aspects such as narrative and interaction completely depend on the camera since the camera defines the player’s point of view. Most research works in automatic camera control aim to take the control of this aspect from the player to automatically gen...

  16. Complete Fabrication of a Traversable 3 µm Thick NbN Film Superconducting Coil with Cu plated layer of 42m in Length in a Spiral Three-Storied Trench Engraved in a Si Wafer of 76.2 mm in Diameter Formed by MEMS Technology for a Compact SMES with High Energy Storage Volume Density

    Science.gov (United States)

    Suzuki, Yasuhiro; Iguchi, Nobuhiro; Adachi, Kazuhiro; Ichiki, Akihisa; Hioki, Tatsumi; Hsu, Che-Wei; Sato, Ryoto; Kumagai, Shinya; Sasaki, Minoru; Noh, Joo-Hyong; Sakurahara, Yuuske; Okabe, Kyohei; Takai, Osamu; Honma, Hideo; Watanabe, Hideo; Sakoda, Hitoshi; Sasagawa, Hiroaki; Doy, Hideyuki; Zhou, Shuliang; Hori, H.; Nishikawa, Shigeaki; Nozaki, Toshihiro; Sugimoto, Noriaki; Motohiro, Tomoyoshi

    2017-09-01

    Based on the concept of a novel approach to make a compact SMES unit composed of a stack of Si wafers using MEMS process proposed previously, a complete fabrication of a traversable 3 µam thick NbN film superconducting coil lined with Cu plated layer of 42m in length in a spiral three-storied trench engraved in and extended over a whole Si-wafer of 76.2 mm in diameter was attained for the first time. With decrease in temperature, the DC resistivity showed a metallic decrease indicating the current pass was in the Cu plated layer and then made a sudden fall to residual contact resistance indicating the shift of current pass from the Cu plated layer to the NbN film at the critical temperature Tc of 15.5K by superconducting transition. The temperature dependence of I-V curve showed the increase in the critical current with decrease in the temperature and the highest critical current measured was 220 mA at 4K which is five times as large as that obtained in the test fabrication as the experimental proof of concept presented in the previous report. This completion of a one wafer superconducting NbN coil is an indispensable step for the next proof of concept of fabrication of series-connected two wafer coils via superconductive joint which will read to series connected 600 wafer coils finally, and for replacement of NbN by high Tc superconductor such as YBa2Cu3O7-x for operation under the cold energy of liquid hydrogen or liquid nitrogen.

  17. SSC 40 mm cable results and 50 mm design discussions

    International Nuclear Information System (INIS)

    Christopherson, D.; Capone, D.; Hannaford, R.; Remsbottom, R.; Jayakumar, R.; Snitchler, G.; Scanlan, R.; Royet, J.

    1990-09-01

    A summary of the cable produced for the 1990 40 mm Dipole Program is presented. The cable design parameters for the 50 mm Dipole Program are discussed, as well as portions of the SSC specification draft. Considerations leading to the final cable configuration and the results of preliminary trials are included. The first iteration of a strand mapping program to automate cable strand maps is introduced. 7 refs., 2 figs., 1 tab

  18. Fundamental length and relativistic length

    International Nuclear Information System (INIS)

    Strel'tsov, V.N.

    1988-01-01

    It si noted that the introduction of fundamental length contradicts the conventional representations concerning the contraction of the longitudinal size of fast-moving objects. The use of the concept of relativistic length and the following ''elongation formula'' permits one to solve this problem

  19. Electron bunch length measurement at the Vanderbilt FEL

    Energy Technology Data Exchange (ETDEWEB)

    Amirmadhi, F.; Brau, C.A.; Mendenhall, M. [Vanderbilt Free-Electron-Laser Center, Nashville, TN (United States)] [and others

    1995-12-31

    During the past few years, a number of experiments have been performed to demonstrate the possibility to extract the longitudinal charge distribution from spectroscopic measurements of the coherent far-infrared radiation emitted as transition radiation or synchrotron radiation. Coherent emission occurs in a spectral region where the wavelength is comparable to or longer than the bunch length, leading to an enhancement of the radiation intensity that is on the order of the number of particles per bunch, as compared to incoherent radiation. This technique is particularly useful in the region of mm and sub-mm bunch lengths, a range where streak-cameras cannot be used for beam diagnostics due to their limited time resolution. Here we report on experiments that go beyond the proof of principle of this technique by applying it to the study and optimization of FEL performance. We investigated the longitudinal bunch length of the Vanderbilt FEL by analyzing the spectrum of coherent transition radiation emitted by the electron bunches. By monitoring the bunch length while applying a bunch-compression technique, the amount of the compression could be easily observed. This enabled us to perform a systematic study of the FEL performance, especially gain and optical pulse width, as a function of the longitudinal electron distribution in the bunch. The results of this study will be presented and discussed.

  20. Flame Length

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Flame length was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The tool...

  1. Portable mini gamma camera for medical applications

    CERN Document Server

    Porras, E; Benlloch, J M; El-Djalil-Kadi-Hanifi, M; López, S; Pavon, N; Ruiz, J A; Sánchez, F; Sebastiá, A

    2002-01-01

    A small, portable and low-cost gamma camera for medical applications has been developed and clinically tested. This camera, based on a scintillator crystal and a Position Sensitive Photo-Multiplier Tube, has a useful field of view of 4.6 cm diameter and provides 2.2 mm of intrinsic spatial resolution. Its mobility and light weight allow to reach the patient from any desired direction. This camera images small organs with high efficiency and so addresses the demand for devices of specific clinical applications. In this paper, we present the camera and briefly describe the procedures that have led us to choose its configuration and the image reconstruction method. The clinical tests and diagnostic capability are also presented and discussed.

  2. Radiation camera exposure control

    International Nuclear Information System (INIS)

    Martone, R.J.; Yarsawich, M.; Wolczek, W.

    1976-01-01

    A system and method for governing the exposure of an image generated by a radiation camera to an image sensing camera is disclosed. The exposure is terminated in response to the accumulation of a predetermined quantity of radiation, defining a radiation density, occurring in a predetermined area. An index is produced which represents the value of that quantity of radiation whose accumulation causes the exposure termination. The value of the predetermined radiation quantity represented by the index is sensed so that the radiation camera image intensity can be calibrated to compensate for changes in exposure amounts due to desired variations in radiation density of the exposure, to maintain the detectability of the image by the image sensing camera notwithstanding such variations. Provision is also made for calibrating the image intensity in accordance with the sensitivity of the image sensing camera, and for locating the index for maintaining its detectability and causing the proper centering of the radiation camera image

  3. New camera systems for fuel services

    International Nuclear Information System (INIS)

    Hummel, W.; Beck, H.J.

    2010-01-01

    AREVA NP Fuel Services have many years of experience in visual examination and measurements on fuel assemblies and associated core components by using state of the art cameras and measuring technologies. The used techniques allow the surface and dimensional characterization of materials and shapes by visual examination. New enhanced and sophisticated technologies for fuel services f. e. are two shielded color camera systems for use under water and close inspection of a fuel assembly. Nowadays the market requirements for detecting and characterization of small defects (lower than the 10th of one mm) or cracks and analyzing surface appearances on an irradiated fuel rod cladding or fuel assembly structure parts have increased. Therefore it is common practice to use movie cameras with higher resolution. The radiation resistance of high resolution CCD cameras is in general very low and it is not possible to use them unshielded close to a fuel assembly. By extending the camera with a mirror system and shielding around the sensitive parts, the movie camera can be utilized for fuel assembly inspection. AREVA NP Fuel Services is now equipped with such kind of movie cameras. (orig.)

  4. Solid state video cameras

    CERN Document Server

    Cristol, Y

    2013-01-01

    Solid State Video Cameras reviews the state of the art in the field of solid-state television cameras as compiled from patent literature. Organized into 10 chapters, the book begins with the basic array types of solid-state imagers and appropriate read-out circuits and methods. Documents relating to improvement of picture quality, such as spurious signal suppression, uniformity correction, or resolution enhancement, are also cited. The last part considerssolid-state color cameras.

  5. First results from the TOPSAT camera

    Science.gov (United States)

    Greenway, Paul; Tosh, Ian; Morris, Nigel; Burton, Gary; Cawley, Steve

    2017-11-01

    The TopSat camera is a low cost remote sensing imager capable of producing 2.5 metre resolution panchromatic imagery, funded by the British National Space Centre's Mosaic programme. The instrument was designed and assembled at the Space Science & Technology Department of the CCLRC's Rutherford Appleton Laboratory (RAL) in the UK, and was launched on the 27th October 2005 from Plesetsk Cosmodrome in Northern Russia on a Kosmos-3M. The camera utilises an off-axis three mirror system, which has the advantages of excellent image quality over a wide field of view, combined with a compactness that makes its overall dimensions smaller than its focal length. Keeping the costs to a minimum has been a major design driver in the development of this camera. The camera is part of the TopSat mission, which is a collaboration between four UK organisations; QinetiQ, Surrey Satellite Technology Ltd (SSTL), RAL and Infoterra. Its objective is to demonstrate provision of rapid response high resolution imagery to fixed and mobile ground stations using a low cost minisatellite. The paper "Development of the TopSat Camera" presented by RAL at the 5th ICSO in 2004 described the opto-mechanical design, assembly, alignment and environmental test methods implemented. Now that the spacecraft is in orbit and successfully acquiring images, this paper presents the first results from the camera and makes an initial assessment of the camera's in-orbit performance.

  6. LSST Camera Optics Design

    Energy Technology Data Exchange (ETDEWEB)

    Riot, V J; Olivier, S; Bauman, B; Pratuch, S; Seppala, L; Gilmore, D; Ku, J; Nordby, M; Foss, M; Antilogus, P; Morgado, N

    2012-05-24

    The Large Synoptic Survey Telescope (LSST) uses a novel, three-mirror, telescope design feeding a camera system that includes a set of broad-band filters and three refractive corrector lenses to produce a flat field at the focal plane with a wide field of view. Optical design of the camera lenses and filters is integrated in with the optical design of telescope mirrors to optimize performance. We discuss the rationale for the LSST camera optics design, describe the methodology for fabricating, coating, mounting and testing the lenses and filters, and present the results of detailed analyses demonstrating that the camera optics will meet their performance goals.

  7. The MVACS Robotic Arm Camera

    Science.gov (United States)

    Keller, H. U.; Hartwig, H.; Kramm, R.; Koschny, D.; Markiewicz, W. J.; Thomas, N.; Fernades, M.; Smith, P. H.; Reynolds, R.; Lemmon, M. T.; Weinberg, J.; Marcialis, R.; Tanner, R.; Boss, B. J.; Oquest, C.; Paige, D. A.

    2001-08-01

    The Robotic Arm Camera (RAC) is one of the key instruments newly developed for the Mars Volatiles and Climate Surveyor payload of the Mars Polar Lander. This lightweight instrument employs a front lens with variable focus range and takes images at distances from 11 mm (image scale 1:1) to infinity. Color images with a resolution of better than 50 μm can be obtained to characterize the Martian soil. Spectral information of nearby objects is retrieved through illumination with blue, green, and red lamp sets. The design and performance of the camera are described in relation to the science objectives and operation. The RAC uses the same CCD detector array as the Surface Stereo Imager and shares the readout electronics with this camera. The RAC is mounted at the wrist of the Robotic Arm and can characterize the contents of the scoop, the samples of soil fed to the Thermal Evolved Gas Analyzer, the Martian surface in the vicinity of the lander, and the interior of trenches dug out by the Robotic Arm. It can also be used to take panoramic images and to retrieve stereo information with an effective baseline surpassing that of the Surface Stereo Imager by about a factor of 3.

  8. Mechatronic design of a fully integrated camera for mini-invasive surgery.

    Science.gov (United States)

    Zazzarini, C C; Patete, P; Baroni, G; Cerveri, P

    2013-06-01

    This paper describes the design features of an innovative fully integrated camera candidate for mini-invasive abdominal surgery with single port or transluminal access. The apparatus includes a CMOS imaging sensor, a light-emitting diode (LED)-based unit for scene illumination, a photodiode for luminance detection, an optical system designed according to the mechanical compensation paradigm, an actuation unit for enabling autofocus and optical zoom, and a control logics based on microcontroller. The bulk of the apparatus is characterized by a tubular shape with a diameter of 10 mm and a length of 35 mm. The optical system, composed of four lens groups, of which two are mobile, has a total length of 13.46 mm and an effective focal length ranging from 1.61 to 4.44 mm with a zoom factor of 2.75×, with a corresponding angular field of view ranging from 16° to 40°. The mechatronics unit, devoted to move the zoom and the focus lens groups, is implemented adopting miniature piezoelectric motors. The control logics implements a closed-loop mechanism, between the LEDs and photodiode, to attain automatic control light. Bottlenecks of the design and some potential issues of the realization are discussed. A potential clinical scenario is introduced.

  9. A focal plane camera for celestial XUV sources

    International Nuclear Information System (INIS)

    Huizenga, H.

    1980-01-01

    This thesis describes the development and performance of a new type of X-ray camera for the 2-250 0 A wavelength range (XUV). The camera features high position resolution (FWHM approximately 0.2 mm at 2 A, -13 erg/cm 2 s in a one year mission. (Auth.)

  10. Thermal Cameras and Applications

    DEFF Research Database (Denmark)

    Gade, Rikke; Moeslund, Thomas B.

    2014-01-01

    Thermal cameras are passive sensors that capture the infrared radiation emitted by all objects with a temperature above absolute zero. This type of camera was originally developed as a surveillance and night vision tool for the military, but recently the price has dropped, significantly opening up...

  11. Fundamental length

    International Nuclear Information System (INIS)

    Pradhan, T.

    1975-01-01

    The concept of fundamental length was first put forward by Heisenberg from purely dimensional reasons. From a study of the observed masses of the elementary particles known at that time, it is sumrised that this length should be of the order of magnitude 1 approximately 10 -13 cm. It was Heisenberg's belief that introduction of such a fundamental length would eliminate the divergence difficulties from relativistic quantum field theory by cutting off the high energy regions of the 'proper fields'. Since the divergence difficulties arise primarily due to infinite number of degrees of freedom, one simple remedy would be the introduction of a principle that limits these degrees of freedom by removing the effectiveness of the waves with a frequency exceeding a certain limit without destroying the relativistic invariance of the theory. The principle can be stated as follows: It is in principle impossible to invent an experiment of any kind that will permit a distintion between the positions of two particles at rest, the distance between which is below a certain limit. A more elegant way of introducing fundamental length into quantum theory is through commutation relations between two position operators. In quantum field theory such as quantum electrodynamics, it can be introduced through the commutation relation between two interpolating photon fields (vector potentials). (K.B.)

  12. Design and first tests of miniature K010X soft x-ray streak and single-frame camera

    Science.gov (United States)

    Lebedev, V. B.; Feldman, G. G.; Myasnikov, A. F.; Chernyshev, N. V.; Shubski, I. I.; Liu, Jingru; Wang, Lijun; Zhang, Yongsheng; Zhao, Xueqin; Zheng, Guoxin; Xiao, Weiwei

    2007-01-01

    Description of a new K010X soft X-ray camera and the first results of it tests carried out in Russia and China are presented. In a streak mode the full sweep time for a 2 cm sweep route length on the image converter screen is from 2 ns up to 600 microseconds. In a single-frame mode the corresponding frame duration is from ~10 ns up to ~ 660 microseconds. Spatial resolution in a single frame mode was not less than 5 l.p./mm for soft X-ray radiation and not less 10 l.p./mm for UV radiation. Spatial resolution in a streak mode for soft X-ray radiation was from 5 up to 10 l.p./mm and for UV radiation on all the sweep ranges was not less than 10 l.p./mm, except for the range of 1 ns/cm where it was 5 l.p./mm. Limiting temporal resolution for UV radiation was near 10 ps and a dynamic range was 200 when full sweep time was 60 ns. The camera has small 430×115×200 mm dimensions, 5.0 kg weight and 10 VA power consumption.

  13. APPLYING CCD CAMERAS IN STEREO PANORAMA SYSTEMS FOR 3D ENVIRONMENT RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    A. Sh. Amini

    2012-07-01

    Full Text Available Proper recontruction of 3D environments is nowadays needed by many organizations and applications. In addition to conventional methods the use of stereo panoramas is an appropriate technique to use due to simplicity, low cost and the ability to view an environment the way it is in reality. This paper investigates the ability of applying stereo CCD cameras for 3D reconstruction and presentation of the environment and geometric measuring among that. For this purpose, a rotating stereo panorama was established using two CCDs with a base-length of 350 mm and a DVR (digital video recorder box. The stereo system was first calibrated using a 3D test-field and used to perform accurate measurements. The results of investigating the system in a real environment showed that although this kind of cameras produce noisy images and they do not have appropriate geometric stability, but they can be easily synchronized, well controlled and reasonable accuracy (about 40 mm in objects at 12 meters distance from the camera can be achieved.

  14. CALIBRATION PROCEDURES ON OBLIQUE CAMERA SETUPS

    Directory of Open Access Journals (Sweden)

    G. Kemper

    2016-06-01

    Full Text Available Beside the creation of virtual animated 3D City models, analysis for homeland security and city planning, the accurately determination of geometric features out of oblique imagery is an important task today. Due to the huge number of single images the reduction of control points force to make use of direct referencing devices. This causes a precise camera-calibration and additional adjustment procedures. This paper aims to show the workflow of the various calibration steps and will present examples of the calibration flight with the final 3D City model. In difference to most other software, the oblique cameras are used not as co-registered sensors in relation to the nadir one, all camera images enter the AT process as single pre-oriented data. This enables a better post calibration in order to detect variations in the single camera calibration and other mechanical effects. The shown sensor (Oblique Imager is based o 5 Phase One cameras were the nadir one has 80 MPIX equipped with a 50 mm lens while the oblique ones capture images with 50 MPix using 80 mm lenses. The cameras are mounted robust inside a housing to protect this against physical and thermal deformations. The sensor head hosts also an IMU which is connected to a POS AV GNSS Receiver. The sensor is stabilized by a gyro-mount which creates floating Antenna –IMU lever arms. They had to be registered together with the Raw GNSS-IMU Data. The camera calibration procedure was performed based on a special calibration flight with 351 shoots of all 5 cameras and registered the GPS/IMU data. This specific mission was designed in two different altitudes with additional cross lines on each flying heights. The five images from each exposure positions have no overlaps but in the block there are many overlaps resulting in up to 200 measurements per points. On each photo there were in average 110 well distributed measured points which is a satisfying number for the camera calibration. In a first

  15. Educational Applications for Digital Cameras.

    Science.gov (United States)

    Cavanaugh, Terence; Cavanaugh, Catherine

    1997-01-01

    Discusses uses of digital cameras in education. Highlights include advantages and disadvantages, digital photography assignments and activities, camera features and operation, applications for digital images, accessory equipment, and comparisons between digital cameras and other digitizers. (AEF)

  16. The laser scanning camera

    International Nuclear Information System (INIS)

    Jagger, M.

    The prototype development of a novel lenseless camera is reported which utilises a laser beam scanned in a raster by means of orthogonal vibrating mirrors to illuminate the field of view. Laser light reflected from the scene is picked up by a conveniently sited photosensitive device and used to modulate the brightness of a T.V. display scanned in synchronism with the moving laser beam, hence producing a T.V. image of the scene. The camera which needs no external lighting system can act in either a wide angle mode or by varying the size and position of the raster can be made to zoom in to view in detail any object within a 40 0 overall viewing angle. The resolution and performance of the camera are described and a comparison of these aspects is made with conventional T.V. cameras. (author)

  17. Advanced CCD camera developments

    Energy Technology Data Exchange (ETDEWEB)

    Condor, A. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    Two charge coupled device (CCD) camera systems are introduced and discussed, describing briefly the hardware involved, and the data obtained in their various applications. The Advanced Development Group Defense Sciences Engineering Division has been actively designing, manufacturing, fielding state-of-the-art CCD camera systems for over a decade. These systems were originally developed for the nuclear test program to record data from underground nuclear tests. Today, new and interesting application for these systems have surfaced and development is continuing in the area of advanced CCD camera systems, with the new CCD camera that will allow experimenters to replace film for x-ray imaging at the JANUS, USP, and NOVA laser facilities.

  18. Gamma camera system

    International Nuclear Information System (INIS)

    Miller, D.W.; Gerber, M.S.; Schlosser, P.A.; Steidley, J.W.

    1980-01-01

    A detailed description is given of a novel gamma camera which is designed to produce superior images than conventional cameras used in nuclear medicine. The detector consists of a solid state detector (e.g. germanium) which is formed to have a plurality of discrete components to enable 2-dimensional position identification. Details of the electronic processing circuits are given and the problems and limitations introduced by noise are discussed in full. (U.K.)

  19. The Circular Camera Movement

    DEFF Research Database (Denmark)

    Hansen, Lennard Højbjerg

    2014-01-01

    It has been an accepted precept in film theory that specific stylistic features do not express specific content. Nevertheless, it is possible to find many examples in the history of film in which stylistic features do express specific content: for instance, the circular camera movement is used re...... such as the circular camera movement. Keywords: embodied perception, embodied style, explicit narration, interpretation, style pattern, television style...

  20. Neutron cameras for ITER

    International Nuclear Information System (INIS)

    Johnson, L.C.; Barnes, C.W.; Batistoni, P.

    1998-01-01

    Neutron cameras with horizontal and vertical views have been designed for ITER, based on systems used on JET and TFTR. The cameras consist of fan-shaped arrays of collimated flight tubes, with suitably chosen detectors situated outside the biological shield. The sight lines view the ITER plasma through slots in the shield blanket and penetrate the vacuum vessel, cryostat, and biological shield through stainless steel windows. This paper analyzes the expected performance of several neutron camera arrangements for ITER. In addition to the reference designs, the authors examine proposed compact cameras, in which neutron fluxes are inferred from 16 N decay gammas in dedicated flowing water loops, and conventional cameras with fewer sight lines and more limited fields of view than in the reference designs. It is shown that the spatial sampling provided by the reference designs is sufficient to satisfy target measurement requirements and that some reduction in field of view may be permissible. The accuracy of measurements with 16 N-based compact cameras is not yet established, and they fail to satisfy requirements for parameter range and time resolution by large margins

  1. Deployable Wireless Camera Penetrators

    Science.gov (United States)

    Badescu, Mircea; Jones, Jack; Sherrit, Stewart; Wu, Jiunn Jeng

    2008-01-01

    A lightweight, low-power camera dart has been designed and tested for context imaging of sampling sites and ground surveys from an aerobot or an orbiting spacecraft in a microgravity environment. The camera penetrators also can be used to image any line-of-sight surface, such as cliff walls, that is difficult to access. Tethered cameras to inspect the surfaces of planetary bodies use both power and signal transmission lines to operate. A tether adds the possibility of inadvertently anchoring the aerobot, and requires some form of station-keeping capability of the aerobot if extended examination time is required. The new camera penetrators are deployed without a tether, weigh less than 30 grams, and are disposable. They are designed to drop from any altitude with the boost in transmitting power currently demonstrated at approximately 100-m line-of-sight. The penetrators also can be deployed to monitor lander or rover operations from a distance, and can be used for surface surveys or for context information gathering from a touch-and-go sampling site. Thanks to wireless operation, the complexity of the sampling or survey mechanisms may be reduced. The penetrators may be battery powered for short-duration missions, or have solar panels for longer or intermittent duration missions. The imaging device is embedded in the penetrator, which is dropped or projected at the surface of a study site at 90 to the surface. Mirrors can be used in the design to image the ground or the horizon. Some of the camera features were tested using commercial "nanny" or "spy" camera components with the charge-coupled device (CCD) looking at a direction parallel to the ground. Figure 1 shows components of one camera that weighs less than 8 g and occupies a volume of 11 cm3. This camera could transmit a standard television signal, including sound, up to 100 m. Figure 2 shows the CAD models of a version of the penetrator. A low-volume array of such penetrator cameras could be deployed from an

  2. The Dark Energy Camera

    Science.gov (United States)

    Flaugher, B.; Diehl, H. T.; Honscheid, K.; Abbott, T. M. C.; Alvarez, O.; Angstadt, R.; Annis, J. T.; Antonik, M.; Ballester, O.; Beaufore, L.; Bernstein, G. M.; Bernstein, R. A.; Bigelow, B.; Bonati, M.; Boprie, D.; Brooks, D.; Buckley-Geer, E. J.; Campa, J.; Cardiel-Sas, L.; Castander, F. J.; Castilla, J.; Cease, H.; Cela-Ruiz, J. M.; Chappa, S.; Chi, E.; Cooper, C.; da Costa, L. N.; Dede, E.; Derylo, G.; DePoy, D. L.; de Vicente, J.; Doel, P.; Drlica-Wagner, A.; Eiting, J.; Elliott, A. E.; Emes, J.; Estrada, J.; Fausti Neto, A.; Finley, D. A.; Flores, R.; Frieman, J.; Gerdes, D.; Gladders, M. D.; Gregory, B.; Gutierrez, G. R.; Hao, J.; Holland, S. E.; Holm, S.; Huffman, D.; Jackson, C.; James, D. J.; Jonas, M.; Karcher, A.; Karliner, I.; Kent, S.; Kessler, R.; Kozlovsky, M.; Kron, R. G.; Kubik, D.; Kuehn, K.; Kuhlmann, S.; Kuk, K.; Lahav, O.; Lathrop, A.; Lee, J.; Levi, M. E.; Lewis, P.; Li, T. S.; Mandrichenko, I.; Marshall, J. L.; Martinez, G.; Merritt, K. W.; Miquel, R.; Muñoz, F.; Neilsen, E. H.; Nichol, R. C.; Nord, B.; Ogando, R.; Olsen, J.; Palaio, N.; Patton, K.; Peoples, J.; Plazas, A. A.; Rauch, J.; Reil, K.; Rheault, J.-P.; Roe, N. A.; Rogers, H.; Roodman, A.; Sanchez, E.; Scarpine, V.; Schindler, R. H.; Schmidt, R.; Schmitt, R.; Schubnell, M.; Schultz, K.; Schurter, P.; Scott, L.; Serrano, S.; Shaw, T. M.; Smith, R. C.; Soares-Santos, M.; Stefanik, A.; Stuermer, W.; Suchyta, E.; Sypniewski, A.; Tarle, G.; Thaler, J.; Tighe, R.; Tran, C.; Tucker, D.; Walker, A. R.; Wang, G.; Watson, M.; Weaverdyck, C.; Wester, W.; Woods, R.; Yanny, B.; DES Collaboration

    2015-11-01

    The Dark Energy Camera is a new imager with a 2.°2 diameter field of view mounted at the prime focus of the Victor M. Blanco 4 m telescope on Cerro Tololo near La Serena, Chile. The camera was designed and constructed by the Dark Energy Survey Collaboration and meets or exceeds the stringent requirements designed for the wide-field and supernova surveys for which the collaboration uses it. The camera consists of a five-element optical corrector, seven filters, a shutter with a 60 cm aperture, and a charge-coupled device (CCD) focal plane of 250 μm thick fully depleted CCDs cooled inside a vacuum Dewar. The 570 megapixel focal plane comprises 62 2k × 4k CCDs for imaging and 12 2k × 2k CCDs for guiding and focus. The CCDs have 15 μm × 15 μm pixels with a plate scale of 0.″263 pixel-1. A hexapod system provides state-of-the-art focus and alignment capability. The camera is read out in 20 s with 6-9 electron readout noise. This paper provides a technical description of the camera's engineering, construction, installation, and current status.

  3. THE DARK ENERGY CAMERA

    Energy Technology Data Exchange (ETDEWEB)

    Flaugher, B.; Diehl, H. T.; Alvarez, O.; Angstadt, R.; Annis, J. T.; Buckley-Geer, E. J. [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); Honscheid, K. [Center for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, OH 43210 (United States); Abbott, T. M. C.; Bonati, M. [Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile); Antonik, M.; Brooks, D. [Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT (United Kingdom); Ballester, O.; Cardiel-Sas, L. [Institut de Física d’Altes Energies, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain); Beaufore, L. [Department of Physics, The Ohio State University, Columbus, OH 43210 (United States); Bernstein, G. M. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 (United States); Bernstein, R. A. [Carnegie Observatories, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Bigelow, B.; Boprie, D. [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Campa, J. [Centro de Investigaciones Energèticas, Medioambientales y Tecnológicas (CIEMAT), Madrid (Spain); Castander, F. J., E-mail: diehl@fnal.gov [Institut de Ciències de l’Espai, IEEC-CSIC, Campus UAB, Facultat de Ciències, Torre C5 par-2, E-08193 Bellaterra, Barcelona (Spain); Collaboration: DES Collaboration; and others

    2015-11-15

    The Dark Energy Camera is a new imager with a 2.°2 diameter field of view mounted at the prime focus of the Victor M. Blanco 4 m telescope on Cerro Tololo near La Serena, Chile. The camera was designed and constructed by the Dark Energy Survey Collaboration and meets or exceeds the stringent requirements designed for the wide-field and supernova surveys for which the collaboration uses it. The camera consists of a five-element optical corrector, seven filters, a shutter with a 60 cm aperture, and a charge-coupled device (CCD) focal plane of 250 μm thick fully depleted CCDs cooled inside a vacuum Dewar. The 570 megapixel focal plane comprises 62 2k × 4k CCDs for imaging and 12 2k × 2k CCDs for guiding and focus. The CCDs have 15 μm × 15 μm pixels with a plate scale of 0.″263 pixel{sup −1}. A hexapod system provides state-of-the-art focus and alignment capability. The camera is read out in 20 s with 6–9 electron readout noise. This paper provides a technical description of the camera's engineering, construction, installation, and current status.

  4. Short cervical length dilemma.

    Science.gov (United States)

    Suhag, Anju; Berghella, Vincenzo

    2015-06-01

    Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. With research efforts, the rate of PTB decreased to 11.4% in 2013. Transvaginal ultrasound (TVU) cervical length (CL) screening predicts PTB. In asymptomatic singletons without prior spontaneous PTB (sPTB), TVU CL screening should be done. If the cervix is 20 mm or less, vaginal progesterone is indicated. In asymptomatic singletons with prior sPTB, serial CL screening is indicated. In multiple gestations, routine cervical screening is not indicated. In symptomatic women with preterm labor, TVU CL screening and fetal fibronectin testing is recommended. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Using a portable holographic camera in cosmetology

    Science.gov (United States)

    Bakanas, R.; Gudaitis, G. A.; Zacharovas, S. J.; Ratcliffe, D. B.; Hirsch, S.; Frey, S.; Thelen, A.; Ladrière, N.; Hering, P.

    2006-07-01

    The HSF-MINI portable holographic camera is used to record holograms of the human face. The recorded holograms are analyzed using a unique three-dimensional measurement system that provides topometric data of the face with resolution less than or equal to 0.5 mm. The main advantages of this method over other, more traditional methods (such as laser triangulation and phase-measurement triangulation) are discussed.

  6. Gate simulation of Compton Ar-Xe gamma-camera for radionuclide imaging in nuclear medicine

    Science.gov (United States)

    Dubov, L. Yu; Belyaev, V. N.; Berdnikova, A. K.; Bolozdynia, A. I.; Akmalova, Yu A.; Shtotsky, Yu V.

    2017-01-01

    Computer simulations of cylindrical Compton Ar-Xe gamma camera are described in the current report. Detection efficiency of cylindrical Ar-Xe Compton camera with internal diameter of 40 cm is estimated as1-3%that is 10-100 times higher than collimated Anger’s camera. It is shown that cylindrical Compton camera can image Tc-99m radiotracer distribution with uniform spatial resolution of 20 mm through the whole field of view.

  7. CALIBRATION PROCEDURES IN MID FORMAT CAMERA SETUPS

    Directory of Open Access Journals (Sweden)

    F. Pivnicka

    2012-07-01

    Full Text Available A growing number of mid-format cameras are used for aerial surveying projects. To achieve a reliable and geometrically precise result also in the photogrammetric workflow, awareness on the sensitive parts is important. The use of direct referencing systems (GPS/IMU, the mounting on a stabilizing camera platform and the specific values of the mid format camera make a professional setup with various calibration and misalignment operations necessary. An important part is to have a proper camera calibration. Using aerial images over a well designed test field with 3D structures and/or different flight altitudes enable the determination of calibration values in Bingo software. It will be demonstrated how such a calibration can be performed. The direct referencing device must be mounted in a solid and reliable way to the camera. Beside the mechanical work especially in mounting the camera beside the IMU, 2 lever arms have to be measured in mm accuracy. Important are the lever arms from the GPS Antenna to the IMU's calibrated centre and also the lever arm from the IMU centre to the Camera projection centre. In fact, the measurement with a total station is not a difficult task but the definition of the right centres and the need for using rotation matrices can cause serious accuracy problems. The benefit of small and medium format cameras is that also smaller aircrafts can be used. Like that, a gyro bases stabilized platform is recommended. This causes, that the IMU must be mounted beside the camera on the stabilizer. The advantage is, that the IMU can be used to control the platform, the problematic thing is, that the IMU to GPS antenna lever arm is floating. In fact we have to deal with an additional data stream, the values of the movement of the stabiliser to correct the floating lever arm distances. If the post-processing of the GPS-IMU data by taking the floating levers into account, delivers an expected result, the lever arms between IMU and

  8. Distribution and Parameter's Calculations of Television Cameras Inside a Nuclear Facility

    International Nuclear Information System (INIS)

    El-kafas, A.A.

    2009-01-01

    In this work, a distribution of television cameras and parameter's calculation inside and outside a nuclear facility is presented. Each of exterior and interior camera systems will be described and explained. The work shows the overall closed circuit television system. Fixed and moving cameras with various lens format and different angles of view are used. The calculations of width of images sensitive area and Lens focal length for the cameras will be introduced. The work shows the camera locations and distributions inside and outside the nuclear facility. The technical specifications and parameters for cameras selection are tabulated

  9. Meteor Film Recording with Digital Film Cameras with large CMOS Sensors

    Science.gov (United States)

    Slansky, P. C.

    2016-12-01

    In this article the author combines his professional know-how about cameras for film and television production with his amateur astronomy activities. Professional digital film cameras with high sensitivity are still quite rare in astronomy. One reason for this may be their costs of up to 20 000 and more (camera body only). In the interim, however,consumer photo cameras with film mode and very high sensitivity have come to the market for about 2 000 EUR. In addition, ultra-high sensitive professional film cameras, that are very interesting for meteor observation, have been introduced to the market. The particular benefits of digital film cameras with large CMOS sensors, including photo cameras with film recording function, for meteor recording are presented by three examples: a 2014 Camelopardalid, shot with a Canon EOS C 300, an exploding 2014 Aurigid, shot with a Sony alpha7S, and the 2016 Perseids, shot with a Canon ME20F-SH. All three cameras use large CMOS sensors; "large" meaning Super-35 mm, the classic 35 mm film format (24x13.5 mm, similar to APS-C size), or full format (36x24 mm), the classic 135 photo camera format. Comparisons are made to the widely used cameras with small CCD sensors, such as Mintron or Watec; "small" meaning 12" (6.4x4.8 mm) or less. Additionally, special photographic image processing of meteor film recordings is discussed.

  10. Tape measuring system using linear encoder and digital camera

    Science.gov (United States)

    Eom, Tae Bong; Jeong, Don Young; Kim, Myung Soon; Kim, Jae Wan; Kim, Jong Ahn

    2013-04-01

    We have designed and constructed the calibration system of line standards such as tape and rule for the secondary calibration laboratories. The system consists of the main body with linear stage and linear encoder, the optical microscope with digital camera, and the computer. The base of the system is a aluminum profile with 2.9 m length, 0.09 m height and 0.18 m width. The linear stage and the linear encoder are fixed on the aluminum profile. The micro-stage driven by micrometer is fixed on the carriage of the long linear stage, and the optical microscope with digital camera and the tablet PC are on the this stage. The linear encoder counts the moving distance of the linear stage with resolution of 1 μm and its counting value is transferred to the tablet PC. The image of the scale mark of the tape is captured by the CCD camera of optical microscope and transferred to the PC through USB interface. The computer automatically determines the center of the scale mark by image processing technique and at the same time reads the moving distance of the linear stage. As a result, the computer can calculate the interval between the scale marks of the tape. In order to achieve the high accuracy, the linear encoder should be calibrated using the laser interferometer or the rigid steel rule. This calibration data of the linear encoder is stored at the computer and the computer corrects the reading value of the linear encoder. In order to determine the center of the scale mark, we use three different algorithms. First, the image profile over specified threshold level is fitted in even order polynomial and the axis of the polynomial is used as the center of the line. Second, the left side and right side areas at the center of the image profile are calculated so that two areas are same. Third, the left and right edges of the image profile are determined at every intensity level of the image and the center of the graduation is calculated as an average of the centers of the left

  11. Communities, Cameras, and Conservation

    Science.gov (United States)

    Patterson, Barbara

    2012-01-01

    Communities, Cameras, and Conservation (CCC) is the most exciting and valuable program the author has seen in her 30 years of teaching field science courses. In this citizen science project, students and community volunteers collect data on mountain lions ("Puma concolor") at four natural areas and public parks along the Front Range of Colorado.…

  12. Mars Observer camera

    Science.gov (United States)

    Malin, M. C.; Danielson, G. E.; Ingersoll, A. P.; Masursky, H.; Veverka, J.; Ravine, M. A.; Soulanille, T. A.

    1992-01-01

    The Mars Observer camera (MOC) is a three-component system (one narrow-angle and two wide-angle cameras) designed to take high spatial resolution pictures of the surface of Mars and to obtain lower spatial resolution, synoptic coverage of the planet's surface and atmosphere. The cameras are based on the 'push broom' technique; that is, they do not take 'frames' but rather build pictures, one line at a time, as the spacecraft moves around the planet in its orbit. MOC is primarily a telescope for taking extremely high resolution pictures of selected locations on Mars. Using the narrow-angle camera, areas ranging from 2.8 km x 2.8 km to 2.8 km x 25.2 km (depending on available internal digital buffer memory) can be photographed at about 1.4 m/pixel. Additionally, lower-resolution pictures (to a lowest resolution of about 11 m/pixel) can be acquired by pixel averaging; these images can be much longer, ranging up to 2.8 x 500 km at 11 m/pixel. High-resolution data will be used to study sediments and sedimentary processes, polar processes and deposits, volcanism, and other geologic/geomorphic processes.

  13. The world's fastest camera

    CERN Multimedia

    Piquepaille, Roland

    2006-01-01

    This image processor is not your typical digital camera. It took 6 years to 20 people and $6 million to build the "Regional Calorimeter Trigger"(RCT) which will be a component of the Compact Muon Solenoid (CMS) experiment, one of the detectors on the Large Hadron Collider (LHC) in Geneva, Switzerland (1 page)

  14. Camera as Cultural Critique

    DEFF Research Database (Denmark)

    Suhr, Christian

    2015-01-01

    researchers, cameras, and filmed subjects already inherently comprise analytical decisions. It is these ethnographic qualities inherent in audiovisual and photographic imagery that make it of particular value to a participatory anthropological enterprise that seeks to resist analytic closure and seeks instead...

  15. Automatic Camera Control

    DEFF Research Database (Denmark)

    Burelli, Paolo; Preuss, Mike

    2014-01-01

    Automatically generating computer animations is a challenging and complex problem with applications in games and film production. In this paper, we investigate howto translate a shot list for a virtual scene into a series of virtual camera configurations — i.e automatically controlling the virtual...

  16. X-ray imaging using digital cameras

    Science.gov (United States)

    Winch, Nicola M.; Edgar, Andrew

    2012-03-01

    The possibility of using the combination of a computed radiography (storage phosphor) cassette and a semiprofessional grade digital camera for medical or dental radiography is investigated. We compare the performance of (i) a Canon 5D Mk II single lens reflex camera with f1.4 lens and full-frame CMOS array sensor and (ii) a cooled CCD-based camera with a 1/3 frame sensor and the same lens system. Both systems are tested with 240 x 180 mm cassettes which are based on either powdered europium-doped barium fluoride bromide or needle structure europium-doped cesium bromide. The modulation transfer function for both systems has been determined and falls to a value of 0.2 at around 2 lp/mm, and is limited by light scattering of the emitted light from the storage phosphor rather than the optics or sensor pixelation. The modulation transfer function for the CsBr:Eu2+ plate is bimodal, with a high frequency wing which is attributed to the light-guiding behaviour of the needle structure. The detective quantum efficiency has been determined using a radioisotope source and is comparatively low at 0.017 for the CMOS camera and 0.006 for the CCD camera, attributed to the poor light harvesting by the lens. The primary advantages of the method are portability, robustness, digital imaging and low cost; the limitations are the low detective quantum efficiency and hence signal-to-noise ratio for medical doses, and restricted range of plate sizes. Representative images taken with medical doses are shown and illustrate the potential use for portable basic radiography.

  17. The PAU Camera

    Science.gov (United States)

    Casas, R.; Ballester, O.; Cardiel-Sas, L.; Carretero, J.; Castander, F. J.; Castilla, J.; Crocce, M.; de Vicente, J.; Delfino, M.; Fernández, E.; Fosalba, P.; García-Bellido, J.; Gaztañaga, E.; Grañena, F.; Jiménez, J.; Madrid, F.; Maiorino, M.; Martí, P.; Miquel, R.; Neissner, C.; Ponce, R.; Sánchez, E.; Serrano, S.; Sevilla, I.; Tonello, N.; Troyano, I.

    2011-11-01

    The PAU Camera (PAUCam) is a wide-field camera designed to be mounted at the William Herschel Telescope (WHT) prime focus, located at the Observatorio del Roque de los Muchachos in the island of La Palma (Canary Islands).Its primary function is to carry out a cosmological survey, the PAU Survey, covering an area of several hundred square degrees of sky. Its purpose is to determine positions and distances using photometric redshift techniques. To achieve accurate photo-z's, PAUCam will be equipped with 40 narrow-band filters covering the range from 450 to850 nm, and six broad-band filters, those of the SDSS system plus the Y band. To fully cover the focal plane delivered by the telescope optics, 18 CCDs 2k x 4k are needed. The pixels are square of 15 μ m size. The optical characteristics of the prime focus corrector deliver a field-of-view where eight of these CCDs will have an illumination of more than 95% covering a field of 40 arc minutes. The rest of the CCDs will occupy the vignetted region extending the field diameter to one degree. Two of the CCDs will be devoted to auto-guiding.This camera have some innovative features. Firstly, both the broad-band and the narrow-band filters will be placed in mobile trays, hosting 16 such filters at most. Those are located inside the cryostat at few millimeters in front of the CCDs when observing. Secondly, a pressurized liquid nitrogen tank outside the camera will feed a boiler inside the cryostat with a controlled massflow. The read-out electronics will use the Monsoon architecture, originally developed by NOAO, modified and manufactured by our team in the frame of the DECam project (the camera used in the DES Survey).PAUCam will also be available to the astronomical community of the WHT.

  18. Broadband Mm-Wave OFDM Communications in Doubly Selective Channel: Performance Evaluation Using Measured Mm-Wave Channel

    DEFF Research Database (Denmark)

    Chen, Xiaoming; Fan, Wei; Pedersen, Gert F.

    2018-01-01

    coefficients of the broadband mm-wave channel do not follow Gaussian distribution due to the broad bandwidth. It is also shown that, given a cyclic prefix (CP) length for a certain delay spread, an effective PN mitigation scheme enables a PN corrupted OFDM system to function with small subcarrier spacing and...

  19. MISR radiometric camera-by-camera Cloud Mask V004

    Data.gov (United States)

    National Aeronautics and Space Administration — This file contains the Radiometric camera-by-camera Cloud Mask dataset. It is used to determine whether a scene is classified as clear or cloudy. A new parameter has...

  20. The WEBERSAT camera - An inexpensive earth imaging system

    Science.gov (United States)

    Jackson, Stephen; Raetzke, Jeffrey

    WEBERSAT is a 27 pound LEO satellite launched in 1990 into a 500 mile polar orbit. One of its payloads is a low cost CCD color camera system developed by engineering students at Weber State University. The camera is a modified Canon CI-10 with a 25 mm lens, automatic iris, and 780 x 490 pixel resolution. The iris range control potentiometer was made programmable; a 10.7 MHz digitization clock, fixed focus support, and solid tantalum capacitors were added. Camera output signals, composite video, red, green, blue, and the digitization clock are fed to a flash digitizer, where they are processed for storage in RAM. Camera control commands are stored and executed via the onboard computer. The CCD camera has successfully imaged meteorological features of the earth, land masses, and a number of astronomical objects.

  1. Optical design of camera optics for mobile phones

    Science.gov (United States)

    Steinich, Thomas; Blahnik, Vladan

    2012-03-01

    At present, compact camera modules are included in many mobile electronic devices such as mobile phones, personal digital assistants or tablet computers. They have various uses, from snapshots of everyday situations to capturing barcodes for product information. This paper presents an overview of the key design challenges and some typical solutions. A lens design for a mobile phone camera is compared to a downscaled 35 mm format lens to demonstrate the main differences in optical design. Particular attention is given to scaling effects.

  2. Cluster eye camera using microlenses on parabolic surface

    Science.gov (United States)

    Shen, Hui-Kai; Su, Guo-Dung J.

    2013-10-01

    There are two main types of imaging systems that exist in nature: the single aperture eye and the compound eye. Usually, cameras and most of artificial imaging systems are similar to the single aperture eye. But compound lenses can be more compact than single lenses. Our design is based on insect compound eyes, which also have a wide field of view (FOV). With the rise of micro-optical techniques, fabricating compound lenses has become easier. The simplest form of a curved microlens array is a parabolic surface. In this paper, we proposed a multi-channel imaging system, which combines the principles of the insect compound eye and the human eye. The optical system enables the reduction of track length of the imaging optics to achieve miniaturization. With the aid of optical engineering software ZEMAX, the multi-channel structure is simulated by a curved microlens array, and we use a Hypergon lens as the main lens to simulate the human eye, which can achieve the purpose of the wide FOV. With this architecture, each microlens of a microlens array transmits a segment of the overall FOV. The partial images that are separately recorded in different channels are stitched together to form the final image of the whole FOV by software processing. A 2.74 mm thin imaging system with 59 channels and 90° FOV is optimized using ZEMAX sequential ray tracing software on a 6.16 mm × 4.62 mm image plane. Finally, we will discuss the simulation results of this system and compare it with the optical cluster eye system and a mobile phone patent.

  3. A novel simultaneous streak and framing camera without principle errors

    Science.gov (United States)

    Jingzhen, L.; Fengshan, S.; Ningwen, L.; Xiangdong, G.; Bin, H.; Qingyang, W.; Hongyi, C.; Yi, C.; Xiaowei, L.

    2018-02-01

    A novel simultaneous streak and framing camera with continuous access, the perfect information of which is far more important for the exact interpretation and precise evaluation of many detonation events and shockwave phenomena, has been developed. The camera with the maximum imaging frequency of 2 × 106 fps and the maximum scanning velocity of 16.3 mm/μs has fine imaging properties which are the eigen resolution of over 40 lp/mm in the temporal direction and over 60 lp/mm in the spatial direction and the framing frequency principle error of zero for framing record, and the maximum time resolving power of 8 ns and the scanning velocity nonuniformity of 0.136%~-0.277% for streak record. The test data have verified the performance of the camera quantitatively. This camera, simultaneously gained frames and streak with parallax-free and identical time base, is characterized by the plane optical system at oblique incidence different from space system, the innovative camera obscura without principle errors, and the high velocity motor driven beryllium-like rotating mirror, made of high strength aluminum alloy with cellular lateral structure. Experiments demonstrate that the camera is very useful and reliable to take high quality pictures of the detonation events.

  4. Global Calibration of Multiple Cameras Based on Sphere Targets

    Directory of Open Access Journals (Sweden)

    Junhua Sun

    2016-01-01

    Full Text Available Global calibration methods for multi-camera system are critical to the accuracy of vision measurement. Proposed in this paper is such a method based on several groups of sphere targets and a precision auxiliary camera. Each camera to be calibrated observes a group of spheres (at least three, while the auxiliary camera observes all the spheres. The global calibration can be achieved after each camera reconstructs the sphere centers in its field of view. In the process of reconstructing a sphere center, a parameter equation is used to describe the sphere projection model. Theoretical analysis and computer simulation are carried out to analyze the factors that affect the calibration accuracy. Simulation results show that the parameter equation can largely improve the reconstruction accuracy. In the experiments, a two-camera system calibrated by our method is used to measure a distance about 578 mm, and the root mean squared error is within 0.14 mm. Furthermore, the experiments indicate that the method has simple operation and good flexibility, especially for the onsite multiple cameras without common field of view.

  5. Machine-Learning-Based Future Received Signal Strength Prediction Using Depth Images for mmWave Communications

    OpenAIRE

    Okamoto, Hironao; Nishio, Takayuki; Nakashima, Kota; Koda, Yusuke; Yamamoto, Koji; Morikura, Masahiro; Asai, Yusuke; Miyatake, Ryo

    2018-01-01

    This paper discusses a machine-learning (ML)-based future received signal strength (RSS) prediction scheme using depth camera images for millimeter-wave (mmWave) networks. The scheme provides the future RSS prediction of any mmWave links within the camera's view, including links where nodes are not transmitting frames. This enables network controllers to conduct network operations before line-of-sight path blockages degrade the RSS. Using the ML techniques, the prediction scheme automatically...

  6. A Portable, Inexpensive, Nonmydriatic Fundus Camera Based on the Raspberry Pi® Computer.

    Science.gov (United States)

    Shen, Bailey Y; Mukai, Shizuo

    2017-01-01

    Purpose. Nonmydriatic fundus cameras allow retinal photography without pharmacologic dilation of the pupil. However, currently available nonmydriatic fundus cameras are bulky, not portable, and expensive. Taking advantage of recent advances in mobile technology, we sought to create a nonmydriatic fundus camera that was affordable and could be carried in a white coat pocket. Methods. We built a point-and-shoot prototype camera using a Raspberry Pi computer, an infrared-sensitive camera board, a dual infrared and white light light-emitting diode, a battery, a 5-inch touchscreen liquid crystal display, and a disposable 20-diopter condensing lens. Our prototype camera was based on indirect ophthalmoscopy with both infrared and white lights. Results. The prototype camera measured 133mm × 91mm × 45mm and weighed 386 grams. The total cost of the components, including the disposable lens, was $185.20. The camera was able to obtain good-quality fundus images without pharmacologic dilation of the pupils. Conclusion. A fully functional, inexpensive, handheld, nonmydriatic fundus camera can be easily assembled from a relatively small number of components. With modest improvements, such a camera could be useful for a variety of healthcare professionals, particularly those who work in settings where a traditional table-mounted nonmydriatic fundus camera would be inconvenient.

  7. A Portable, Inexpensive, Nonmydriatic Fundus Camera Based on the Raspberry Pi® Computer

    Directory of Open Access Journals (Sweden)

    Bailey Y. Shen

    2017-01-01

    Full Text Available Purpose. Nonmydriatic fundus cameras allow retinal photography without pharmacologic dilation of the pupil. However, currently available nonmydriatic fundus cameras are bulky, not portable, and expensive. Taking advantage of recent advances in mobile technology, we sought to create a nonmydriatic fundus camera that was affordable and could be carried in a white coat pocket. Methods. We built a point-and-shoot prototype camera using a Raspberry Pi computer, an infrared-sensitive camera board, a dual infrared and white light light-emitting diode, a battery, a 5-inch touchscreen liquid crystal display, and a disposable 20-diopter condensing lens. Our prototype camera was based on indirect ophthalmoscopy with both infrared and white lights. Results. The prototype camera measured 133mm×91mm×45mm and weighed 386 grams. The total cost of the components, including the disposable lens, was $185.20. The camera was able to obtain good-quality fundus images without pharmacologic dilation of the pupils. Conclusion. A fully functional, inexpensive, handheld, nonmydriatic fundus camera can be easily assembled from a relatively small number of components. With modest improvements, such a camera could be useful for a variety of healthcare professionals, particularly those who work in settings where a traditional table-mounted nonmydriatic fundus camera would be inconvenient.

  8. Accuracy Potential and Applications of MIDAS Aerial Oblique Camera System

    Science.gov (United States)

    Madani, M.

    2012-07-01

    Airborne oblique cameras such as Fairchild T-3A were initially used for military reconnaissance in 30s. A modern professional digital oblique camera such as MIDAS (Multi-camera Integrated Digital Acquisition System) is used to generate lifelike three dimensional to the users for visualizations, GIS applications, architectural modeling, city modeling, games, simulators, etc. Oblique imagery provide the best vantage for accessing and reviewing changes to the local government tax base, property valuation assessment, buying & selling of residential/commercial for better decisions in a more timely manner. Oblique imagery is also used for infrastructure monitoring making sure safe operations of transportation, utilities, and facilities. Sanborn Mapping Company acquired one MIDAS from TrackAir in 2011. This system consists of four tilted (45 degrees) cameras and one vertical camera connected to a dedicated data acquisition computer system. The 5 digital cameras are based on the Canon EOS 1DS Mark3 with Zeiss lenses. The CCD size is 5,616 by 3,744 (21 MPixels) with the pixel size of 6.4 microns. Multiple flights using different camera configurations (nadir/oblique (28 mm/50 mm) and (50 mm/50 mm)) were flown over downtown Colorado Springs, Colorado. Boresight fights for 28 mm nadir camera were flown at 600 m and 1,200 m and for 50 mm nadir camera at 750 m and 1500 m. Cameras were calibrated by using a 3D cage and multiple convergent images utilizing Australis model. In this paper, the MIDAS system is described, a number of real data sets collected during the aforementioned flights are presented together with their associated flight configurations, data processing workflow, system calibration and quality control workflows are highlighted and the achievable accuracy is presented in some detail. This study revealed that the expected accuracy of about 1 to 1.5 GSD (Ground Sample Distance) for planimetry and about 2 to 2.5 GSD for vertical can be achieved. Remaining systematic

  9. ACCURACY POTENTIAL AND APPLICATIONS OF MIDAS AERIAL OBLIQUE CAMERA SYSTEM

    Directory of Open Access Journals (Sweden)

    M. Madani

    2012-07-01

    Full Text Available Airborne oblique cameras such as Fairchild T-3A were initially used for military reconnaissance in 30s. A modern professional digital oblique camera such as MIDAS (Multi-camera Integrated Digital Acquisition System is used to generate lifelike three dimensional to the users for visualizations, GIS applications, architectural modeling, city modeling, games, simulators, etc. Oblique imagery provide the best vantage for accessing and reviewing changes to the local government tax base, property valuation assessment, buying & selling of residential/commercial for better decisions in a more timely manner. Oblique imagery is also used for infrastructure monitoring making sure safe operations of transportation, utilities, and facilities. Sanborn Mapping Company acquired one MIDAS from TrackAir in 2011. This system consists of four tilted (45 degrees cameras and one vertical camera connected to a dedicated data acquisition computer system. The 5 digital cameras are based on the Canon EOS 1DS Mark3 with Zeiss lenses. The CCD size is 5,616 by 3,744 (21 MPixels with the pixel size of 6.4 microns. Multiple flights using different camera configurations (nadir/oblique (28 mm/50 mm and (50 mm/50 mm were flown over downtown Colorado Springs, Colorado. Boresight fights for 28 mm nadir camera were flown at 600 m and 1,200 m and for 50 mm nadir camera at 750 m and 1500 m. Cameras were calibrated by using a 3D cage and multiple convergent images utilizing Australis model. In this paper, the MIDAS system is described, a number of real data sets collected during the aforementioned flights are presented together with their associated flight configurations, data processing workflow, system calibration and quality control workflows are highlighted and the achievable accuracy is presented in some detail. This study revealed that the expected accuracy of about 1 to 1.5 GSD (Ground Sample Distance for planimetry and about 2 to 2.5 GSD for vertical can be achieved. Remaining

  10. A miniature VGA SWIR camera using MT6415CA ROIC

    Science.gov (United States)

    Eminoglu, Selim; Yilmaz, S. Gokhan; Kocak, Serhat

    2014-06-01

    This paper reports the development of a new miniature VGA SWIR camera called NanoCAM-6415, which is developed to demonstrate the key features of the MT6415CA ROIC such as high integration level, low-noise, and low-power in a small volume. The NanoCAM-6415 uses an InGaAs Focal Plane Array (FPA) with a format of 640 × 512 and pixel pitch of 15 μm built using MT6415CA ROIC. MT6415CA is a low-noise CTIA ROIC, which has a system-on-chip architecture, allows generation of all the required timing and biases on-chip in the ROIC without requiring any external components or inputs, thus enabling the development of compact and low-noise SWIR cameras, with reduced size, weight, and power (SWaP). NanoCAM-6415 camera supports snapshot operation using Integrate-Then-Read (ITR) and Integrate-While-Read (IWR) modes. The camera has three gain settings enabled by the ROIC through programmable Full-Well-Capacity (FWC) values of 10.000 e-, 20.000 e-, and 350.000 e- in the very high gain (VHG), high-gain (HG), and low-gain (LG) modes, respectively. The camera has an input referred noise level of 10 e- rms in the VHG mode at 1 ms integration time, suitable for low-noise SWIR imaging applications. In order to reduce the size and power of the camera, only 2 outputs out of 8 of the ROIC are connected to the external Analog-to-Digital Converters (ADCs) in the camera electronics, providing a maximum frame rate of 50 fps through a 26-pin SDR type Camera Link connector. NanoCAM-6415 SWIR camera without the optics measures 32 mm × 32 mm × 35 mm, weighs 45gr, and dissipates less than 1.8 W using a 5 V supply. These results show that MT6415CA ROIC can successfully be used to develop cameras for SWIR imaging applications where SWaP is a concern. Mikro-Tasarim has also developed new imaging software to demonstrate the functionality of this miniature VGA camera. Mikro-Tasarim provides tested ROIC wafers and also offers compact and easy-to-use test electronics, demo cameras, and hardware

  11. Body worn camera

    Science.gov (United States)

    Aishwariya, A.; Pallavi Sudhir, Gulavani; Garg, Nemesa; Karthikeyan, B.

    2017-11-01

    A body worn camera is small video camera worn on the body, typically used by police officers to record arrests, evidence from crime scenes. It helps preventing and resolving complaints brought by members of the public; and strengthening police transparency, performance, and accountability. The main constants of this type of the system are video format, resolution, frames rate, and audio quality. This system records the video in .mp4 format with 1080p resolution and 30 frames per second. One more important aspect to while designing this system is amount of power the system requires as battery management becomes very critical. The main design challenges are Size of the Video, Audio for the video. Combining both audio and video and saving it in .mp4 format, Battery, size that is required for 8 hours of continuous recording, Security. For prototyping this system is implemented using Raspberry Pi model B.

  12. Positron emission tomography camera

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    A positron emission tomography camera having a plurality of detector rings positioned side-by-side or offset by one-half of the detector cross section around a patient area to detect radiation therefrom. Each ring contains a plurality of scintillation detectors which are positioned around an inner circumference with a septum ring extending inwardly from the inner circumference along each outer edge of each ring. An additional septum ring is positioned in the middle of each ring of detectors and parallel to the other septa rings, whereby the inward extent of all the septa rings may be reduced by one-half and the number of detectors required in each ring is reduced. The additional septa reduces the costs of the positron camera and improves its performance

  13. The NEAT Camera Project

    Science.gov (United States)

    Jr., Ray L. Newburn

    1995-01-01

    The NEAT (Near Earth Asteroid Tracking) camera system consists of a camera head with a 6.3 cm square 4096 x 4096 pixel CCD, fast electronics, and a Sun Sparc 20 data and control computer with dual CPUs, 256 Mbytes of memory, and 36 Gbytes of hard disk. The system was designed for optimum use with an Air Force GEODSS (Ground-based Electro-Optical Deep Space Surveillance) telescope. The GEODSS telescopes have 1 m f/2.15 objectives of the Ritchey-Chretian type, designed originally for satellite tracking. Installation of NEAT began July 25 at the Air Force Facility on Haleakala, a 3000 m peak on Maui in Hawaii.

  14. Gamma camera display system

    International Nuclear Information System (INIS)

    Stout, K.J.

    1976-01-01

    A gamma camera having an array of photomultipliers coupled via pulse shaping circuitry and a resistor weighting circuit to a display for forming an image of a radioactive subject is described. A linearizing circuit is coupled to the weighting circuit, the linearizing circuit including a nonlinear feedback circuit with diode coupling to the weighting circuit for linearizing the correspondence between points of the display and points of the subject. 4 Claims, 5 Drawing Figures

  15. Scanning gamma camera

    International Nuclear Information System (INIS)

    Engdahl, L.W.; Batter, J.F. Jr.; Stout, K.J.

    1977-01-01

    A scanning system for a gamma camera providing for the overlapping of adjacent scan paths is described. A collimator mask having tapered edges provides for a graduated reduction in intensity of radiation received by a detector thereof, the reduction in intensity being graduated in a direction normal to the scanning path to provide a blending of images of adjacent scan paths. 31 claims, 15 figures

  16. Bunch length measurements in the SLC damping ring

    International Nuclear Information System (INIS)

    Decker, F.J.; Limberg, T.; Minty, M.; Ross, M.

    1993-05-01

    The synchrotron light of the SLC damping ring was used to measure the bunch length with a streak camera at different times in the damping cycle. There are bunch length oscillations after injection, different equilibrium length during the cycle due to rf manipulations to avoid microwave instability oscillations, and just before extraction there is a longitudinal phase space rotation (bunch muncher) to shorten the bunch length. Measurements under these different conditions are presented and compared with BPM pulse height signals. Calibration and adjustment issues and the connection of the streak camera to the SLC control system are also discussed

  17. A comparison of multi-view 3D reconstruction of a rock wall using several cameras and a laser scanner

    Directory of Open Access Journals (Sweden)

    K. Thoeni

    2014-06-01

    Full Text Available This work presents a comparative study between multi-view 3D reconstruction using various digital cameras and a terrestrial laser scanner (TLS. Five different digital cameras were used in order to estimate the limits related to the camera type and to establish the minimum camera requirements to obtain comparable results to the ones of the TLS. The cameras used for this study range from commercial grade to professional grade and included a GoPro Hero 1080 (5 Mp, iPhone 4S (8 Mp, Panasonic Lumix LX5 (9.5 Mp, Panasonic Lumix ZS20 (14.1 Mp and Canon EOS 7D (18 Mp. The TLS used for this work was a FARO Focus 3D laser scanner with a range accuracy of ±2 mm. The study area is a small rock wall of about 6 m height and 20 m length. The wall is partly smooth with some evident geological features, such as non-persistent joints and sharp edges. Eight control points were placed on the wall and their coordinates were measured by using a total station. These coordinates were then used to georeference all models. A similar number of images was acquired from a distance of between approximately 5 to 10 m, depending on field of view of each camera. The commercial software package PhotoScan was used to process the images, georeference and scale the models, and to generate the dense point clouds. Finally, the open-source package CloudCompare was used to assess the accuracy of the multi-view results. Each point cloud obtained from a specific camera was compared to the point cloud obtained with the TLS. The latter is taken as ground truth. The result is a coloured point cloud for each camera showing the deviation in relation to the TLS data. The main goal of this study is to quantify the quality of the multi-view 3D reconstruction results obtained with various cameras as objectively as possible and to evaluate its applicability to geotechnical problems.

  18. Quantitative analysis of cone photoreceptor distribution and its relationship with axial length, age, and early age-related macular degeneration.

    Directory of Open Access Journals (Sweden)

    Ryo Obata

    Full Text Available PURPOSE: It has not been clarified whether early age-related macular degeneration (AMD is associated with cone photoreceptor distribution. We used adaptive optics fundus camera to examine cone photoreceptors in the macular area of aged patients and quantitatively analyzed its relationship between the presence of early AMD and cone distribution. METHODS: Sixty cases aged 50 or older were studied. The eyes were examined with funduscopy and spectral-domain optical coherence tomography to exclude the eyes with any abnormalities at two sites of measurement, 2° superior and 5° temporal to the fovea. High-resolution retinal images with cone photoreceptor mosaic were obtained with adaptive optics fundus camera (rtx1, Imagine Eyes, France. After adjusting for axial length, cone packing density was calculated and the relationship with age, axial length, or severity of early AMD based on the age-related eye disease study (AREDS classification was analyzed. RESULTS: Patient's age ranged from 50 to 77, and axial length from 21.7 to 27.5 mm. Mean density in metric units and that in angular units were 24,900 cells/mm2, 2,170 cells/deg2 at 2° superior, and 18,500 cells/mm2, 1,570 cels/deg2 at 5° temporal, respectively. Axial length was significantly correlated with the density calculated in metric units, but not with that in angular units. Age was significantly correlated with the density both in metric and angular units at 2° superior. There was no significant difference in the density in metric and angular units between the eyes with AREDS category one and those with categories two or three. CONCLUSION: Axial length and age were significantly correlated with parafoveal cone photoreceptor distribution. The results do not support that early AMD might influence cone photoreceptor density in the area without drusen or pigment abnormalities.

  19. Cervical SPECT Camera for Parathyroid Imaging

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2012-08-31

    Primary hyperparathyroidism characterized by one or more enlarged parathyroid glands has become one of the most common endocrine diseases in the world affecting about 1 per 1000 in the United States. Standard treatment is highly invasive exploratory neck surgery called Parathyroidectomy. The surgery has a notable mortality rate because of the close proximity to vital structures. The move to minimally invasive parathyroidectomy is hampered by the lack of high resolution pre-surgical imaging techniques that can accurately localize the parathyroid with respect to surrounding structures. We propose to develop a dedicated ultra-high resolution (~ 1 mm) and high sensitivity (10x conventional camera) cervical scintigraphic imaging device. It will be based on a multiple pinhole-camera SPECT system comprising a novel solid state CZT detector that offers the required performance. The overall system will be configured to fit around the neck and comfortably image a patient.

  20. Radiation-resistant camera tube

    International Nuclear Information System (INIS)

    Kuwahata, Takao; Manabe, Sohei; Makishima, Yasuhiro

    1982-01-01

    It was a long time ago that Toshiba launched on manufacturing black-and-white radiation-resistant camera tubes employing nonbrowning face-plate glass for ITV cameras used in nuclear power plants. Now in compliance with the increasing demand in nuclear power field, the Company is at grips with the development of radiation-resistant single color-camera tubes incorporating a color-stripe filter for color ITV cameras used under radiation environment. Herein represented are the results of experiments on characteristics of materials for single color-camera tubes and prospects for commercialization of the tubes. (author)

  1. The PLATO camera

    Science.gov (United States)

    Laubier, D.; Bodin, P.; Pasquier, H.; Fredon, S.; Levacher, P.; Vola, P.; Buey, T.; Bernardi, P.

    2017-11-01

    PLATO (PLAnetary Transits and Oscillation of stars) is a candidate for the M3 Medium-size mission of the ESA Cosmic Vision programme (2015-2025 period). It is aimed at Earth-size and Earth-mass planet detection in the habitable zone of bright stars and their characterisation using the transit method and the asterosismology of their host star. That means observing more than 100 000 stars brighter than magnitude 11, and more than 1 000 000 brighter than magnitude 13, with a long continuous observing time for 20 % of them (2 to 3 years). This yields a need for an unusually long term signal stability. For the brighter stars, the noise requirement is less than 34 ppm.hr-1/2, from a frequency of 40 mHz down to 20 μHz, including all sources of noise like for instance the motion of the star images on the detectors and frequency beatings. Those extremely tight requirements result in a payload consisting of 32 synchronised, high aperture, wide field of view cameras thermally regulated down to -80°C, whose data are combined to increase the signal to noise performances. They are split into 4 different subsets pointing at 4 directions to widen the total field of view; stars in the centre of that field of view are observed by all 32 cameras. 2 extra cameras are used with color filters and provide pointing measurement to the spacecraft Attitude and Orbit Control System (AOCS) loop. The satellite is orbiting the Sun at the L2 Lagrange point. This paper presents the optical, electronic and electrical, thermal and mechanical designs devised to achieve those requirements, and the results from breadboards developed for the optics, the focal plane, the power supply and video electronics.

  2. Superconducting millimetre-wave cameras

    Science.gov (United States)

    Monfardini, Alessandro

    2017-05-01

    I present a review of the developments in kinetic inductance detectors (KID) for mm-wave and THz imaging-polarimetry in the framework of the Grenoble collaboration. The main application that we have targeted so far is large field-of-view astronomy. I focus in particular on our own experiment: NIKA2 (Néel IRAM KID Arrays). NIKA2 is today the largest millimetre camera available to the astronomical community for general purpose observations. It consists of a dual-band, dual-polarisation, multi-thousands pixels system installed at the IRAM 30-m telescope at Pico Veleta (Spain). I start with a general introduction covering the underlying physics and the KID working principle. Then I describe briefly the instrument and the detectors, to conclude with examples of pictures taken on the Sky by NIKA2 and its predecessor, NIKA. Thanks to these results, together with the relative simplicity and low cost of the KID fabrication, industrial applications requiring passive millimetre-THz imaging have now become possible.

  3. Estimating 3D Leaf and Stem Shape of Nursery Paprika Plants by a Novel Multi-Camera Photography System

    Science.gov (United States)

    Zhang, Yu; Teng, Poching; Shimizu, Yo; Hosoi, Fumiki; Omasa, Kenji

    2016-01-01

    For plant breeding and growth monitoring, accurate measurements of plant structure parameters are very crucial. We have, therefore, developed a high efficiency Multi-Camera Photography (MCP) system combining Multi-View Stereovision (MVS) with the Structure from Motion (SfM) algorithm. In this paper, we measured six variables of nursery paprika plants and investigated the accuracy of 3D models reconstructed from photos taken by four lens types at four different positions. The results demonstrated that error between the estimated and measured values was small, and the root-mean-square errors (RMSE) for leaf width/length and stem height/diameter were 1.65 mm (R2 = 0.98) and 0.57 mm (R2 = 0.99), respectively. The accuracies of the 3D model reconstruction of leaf and stem by a 28-mm lens at the first and third camera positions were the highest, and the number of reconstructed fine-scale 3D model shape surfaces of leaf and stem is the most. The results confirmed the practicability of our new method for the reconstruction of fine-scale plant model and accurate estimation of the plant parameters. They also displayed that our system is a good system for capturing high-resolution 3D images of nursery plants with high efficiency. PMID:27314348

  4. Estimating 3D Leaf and Stem Shape of Nursery Paprika Plants by a Novel Multi-Camera Photography System.

    Science.gov (United States)

    Zhang, Yu; Teng, Poching; Shimizu, Yo; Hosoi, Fumiki; Omasa, Kenji

    2016-06-14

    For plant breeding and growth monitoring, accurate measurements of plant structure parameters are very crucial. We have, therefore, developed a high efficiency Multi-Camera Photography (MCP) system combining Multi-View Stereovision (MVS) with the Structure from Motion (SfM) algorithm. In this paper, we measured six variables of nursery paprika plants and investigated the accuracy of 3D models reconstructed from photos taken by four lens types at four different positions. The results demonstrated that error between the estimated and measured values was small, and the root-mean-square errors (RMSE) for leaf width/length and stem height/diameter were 1.65 mm (R² = 0.98) and 0.57 mm (R² = 0.99), respectively. The accuracies of the 3D model reconstruction of leaf and stem by a 28-mm lens at the first and third camera positions were the highest, and the number of reconstructed fine-scale 3D model shape surfaces of leaf and stem is the most. The results confirmed the practicability of our new method for the reconstruction of fine-scale plant model and accurate estimation of the plant parameters. They also displayed that our system is a good system for capturing high-resolution 3D images of nursery plants with high efficiency.

  5. Stereoscopic camera design

    Science.gov (United States)

    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.

  6. Development of a high-resolution Si-PM-based gamma camera system

    International Nuclear Information System (INIS)

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Hatazawa, Jun; Imaizumi, Masao; Watabe, Tadashi; Shimosegawa, Eku

    2011-01-01

    A silicon photomultiplier (Si-PM) is a promising photodetector for PET, especially for PET/MRI combined systems, due to its high gain, small size, and lower sensitivity to static magnetic fields. However, these properties are also promising for gamma camera systems for single-photon imaging. We developed an ultra-high-resolution Si-PM-based compact gamma camera system for small animals. Y 2 SiO 5 :Ce (YSO) was selected as scintillators because of its high light output and no natural radioactivity. The gamma camera consists of 0.6 mm × 0.6 mm × 6 mm YSO pixels combined with a 0.1 mm thick reflector to form a 17 × 17 matrix that was optically coupled to a Si-PM array (Hamamatsu multi-pixel photon counter S11064-050P) with a 2 mm thick light guide. The YSO block size was 12 mm × 12 mm. The YSO gamma camera was encased in a 5 mm thick gamma shield, and a parallel hole collimator was mounted in front of the camera (0.5 mm hole, 0.7 mm separation, 5 mm thick). The two-dimensional distribution for the Co-57 gamma photons (122 keV) was almost resolved. The energy resolution was 24.4% full-width at half-maximum (FWHM) for the Co-57 gamma photons. The spatial resolution at 1.5 mm from the collimator surface was 1.25 mm FWHM measured using a 1 mm diameter Co-57 point source. Phantom and small animal images were successfully obtained. We conclude that a Si-PM-based gamma camera is promising for molecular imaging research.

  7. Margin Reflex Distance: Differences Based on Camera and Flash Positions.

    Science.gov (United States)

    Choi, Catherine J; Chou, Jonathan C; Lefebvre, Daniel R; Yoon, Michael K

    2016-01-01

    To evaluate the effect of camera flash position on the measurement of photographic margin reflex distances (MRD). Subjects without any ophthalmic disease were prospectively enrolled after institutional review board approval. Clinical measurements of MRD1 and interpalpebral fissure were obtained. Photographs were then taken with a digital single lens reflex with built-in pop-up flash (dSLR-pop), a dSLR with lens-mounted ring flash (dSLR-ring), a point-and-shoot camera, and a smartphone, each in 4 positions: with the camera upright, rotated 90°, 180°, and 270°. The images were analyzed using ImageJ software to measure MRD1, interpalpebral fissure, horizontal white-to-white, and distance from nasal limbus to the corneal light reflex. Thirty-two eyes of 16 subjects were included (ages 27-65). When using the dSLR-ring, point-and-shoot, and smartphone, the difference between clinical and photographic MRD1 did not reach statistical significance. There was, however, a statistically significant difference in the upright position with dSLR-pop (mean difference 0.703 mm, σ = 0.984 mm, p = 0.0008). For dSLR-pop, photographic MRD1 in upright versus inverted position differed significantly (mean difference -0.562 mm, σ =0.348 mm, p MRD1 between dSLR-pop and dSLR-ring showed significant difference in upright position (mean difference -0.572 mm, σ = 0.701 mm, p = 0.0002). There were no statistically significant differences between clinical and photographic interpalpebral fissure, and among white-to-white and nasal limbus to light reflex measurements in any position in all 4 cameras. When using photographs for measurement of MRD1, cameras with a near-coaxial light source and aperture have values that are most similar to clinical measurements.

  8. Collimator trans-axial tomographic scintillation camera

    International Nuclear Information System (INIS)

    Jaszczak, R.J.

    1977-01-01

    A collimator is provided for a scintillation camera system in which a detector precesses in an orbit about a patient. The collimator is designed to have high resolution and lower sensitivity with respect to radiation traveling in paths laying wholly within planes perpendicular to the cranial-caudal axis of the patient. The collimator has high sensitivity and lower resolution to radiation traveling in other planes. Variances in resolution and sensitivity are achieved by altering the length, spacing or thickness of the septa of the collimator

  9. The suitability of lightfield camera depth maps for coordinate measurement applications

    Science.gov (United States)

    Rangappa, Shreedhar; Tailor, Mitul; Petzing, Jon; Kinnell, Peter; Jackson, Michael

    2015-12-01

    Plenoptic cameras can capture 3D information in one exposure without the need for structured illumination, allowing grey scale depth maps of the captured image to be created. The Lytro, a consumer grade plenoptic camera, provides a cost effective method of measuring depth of multiple objects under controlled lightning conditions. In this research, camera control variables, environmental sensitivity, image distortion characteristics, and the effective working range of two Lytro first generation cameras were evaluated. In addition, a calibration process has been created, for the Lytro cameras, to deliver three dimensional output depth maps represented in SI units (metre). The novel results show depth accuracy and repeatability of +10.0 mm to -20.0 mm, and 0.5 mm respectively. For the lateral X and Y coordinates, the accuracy was +1.56 μm to -2.59 μm and the repeatability was 0.25 μm.

  10. A Neutron Streak Camera Designed for ICF Fuel Ion Temperature

    Science.gov (United States)

    Chen, Jiabin; Liao, Hua; Chen, Ming

    2007-11-01

    A neutron streak camera was designed for inertial confinement fusion (ICF) fuel ion temperature diagnostic. It is made of a 1 cm thick x8 cm diam piece of 3% benzophenone quenched plastic scintillator with about a 190 ps FWHM and a streak tube (55ps time resolution) with large-area photocathode (φ30 mm) showed no slit. The electron beam from the photocathode is focused into a little spot (φ1mm). Then the spot is scanned directly and multiplied by an internal microchannel plate. This greatly improves the sensitivity of the tube. The neutron streak camera combines the advangtages of scintillation detector (with high neutron detection efficiency) and of streak camera (with fast time response). The whole detection system time resolution is 300ps and can record neutron time of flight signals from ICF implosion target with yields of 10^7 DT neutron per shot.

  11. A SPECT Scanner for Rodent Imaging Based on Small-Area Gamma Cameras

    Science.gov (United States)

    Lage, Eduardo; Villena, José L.; Tapias, Gustavo; Martinez, Naira P.; Soto-Montenegro, Maria L.; Abella, Mónica; Sisniega, Alejandro; Pino, Francisco; Ros, Domènec; Pavia, Javier; Desco, Manuel; Vaquero, Juan J.

    2010-10-01

    We developed a cost-effective SPECT scanner prototype (rSPECT) for in vivo imaging of rodents based on small-area gamma cameras. Each detector consists of a position-sensitive photomultiplier tube (PS-PMT) coupled to a 30 x 30 Nal(Tl) scintillator array and electronics attached to the PS-PMT sockets for adapting the detector signals to an in-house developed data acquisition system. The detector components are enclosed in a lead-shielded case with a receptacle to insert the collimators. System performance was assessed using 99mTc for a high-resolution parallel-hole collimator, and for a 0.75-mm pinhole collimator with a 60° aperture angle and a 42-mm collimator length. The energy resolution is about 10.7% of the photopeak energy. The overall system sensitivity is about 3 cps/μCi/detector and planar spatial resolution ranges from 2.4 mm at 1 cm source-to-collimator distance to 4.1 mm at 4.5 cm with parallel-hole collimators. With pinhole collimators planar spatial resolution ranges from 1.2 mm at 1 cm source-to-collimator distance to 2.4 mm at 4.5 cm; sensitivity at these distances ranges from 2.8 to 0.5 cps/μCi/detector. Tomographic hot-rod phantom images are presented together with images of bone, myocardium and brain of living rodents to demonstrate the feasibility of preclinical small-animal studies with the rSPECT.

  12. Junocam: Juno's Outreach Camera

    Science.gov (United States)

    Hansen, C. J.; Caplinger, M. A.; Ingersoll, A.; Ravine, M. A.; Jensen, E.; Bolton, S.; Orton, G.

    2017-11-01

    Junocam is a wide-angle camera designed to capture the unique polar perspective of Jupiter offered by Juno's polar orbit. Junocam's four-color images include the best spatial resolution ever acquired of Jupiter's cloudtops. Junocam will look for convective clouds and lightning in thunderstorms and derive the heights of the clouds. Junocam will support Juno's radiometer experiment by identifying any unusual atmospheric conditions such as hotspots. Junocam is on the spacecraft explicitly to reach out to the public and share the excitement of space exploration. The public is an essential part of our virtual team: amateur astronomers will supply ground-based images for use in planning, the public will weigh in on which images to acquire, and the amateur image processing community will help process the data.

  13. Determining Vision Graphs for Distributed Camera Networks Using Feature Digests

    Directory of Open Access Journals (Sweden)

    Richard J. Radke

    2007-01-01

    Full Text Available We propose a decentralized method for obtaining the vision graph for a distributed, ad-hoc camera network, in which each edge of the graph represents two cameras that image a sufficiently large part of the same environment. Each camera encodes a spatially well-distributed set of distinctive, approximately viewpoint-invariant feature points into a fixed-length “feature digest” that is broadcast throughout the network. Each receiver camera robustly matches its own features with the decompressed digest and decides whether sufficient evidence exists to form a vision graph edge. We also show how a camera calibration algorithm that passes messages only along vision graph edges can recover accurate 3D structure and camera positions in a distributed manner. We analyze the performance of different message formation schemes, and show that high detection rates (>0.8 can be achieved while maintaining low false alarm rates (<0.05 using a simulated 60-node outdoor camera network.

  14. Automatic locking radioisotope camera lock

    International Nuclear Information System (INIS)

    Rosauer, P.J.

    1978-01-01

    The lock of the present invention secures the isotope source in a stored shielded condition in the camera until a positive effort has been made to open the lock and take the source outside of the camera and prevents disconnection of the source pigtail unless the source is locked in a shielded condition in the camera. It also gives a visual indication of the locked or possible exposed condition of the isotope source and prevents the source pigtail from being completely pushed out of the camera, even when the lock is released. (author)

  15. Broadband Mm-Wave OFDM Communications in Doubly Selective Channel: Performance Evaluation Using Measured Mm-Wave Channel

    DEFF Research Database (Denmark)

    Chen, Xiaoming; Fan, Wei; Pedersen, Gert F.

    2018-01-01

    coefficients of the broadband mm-wave channel do not follow Gaussian distribution due to the broad bandwidth. It is also shown that, given a cyclic prefix (CP) length for a certain delay spread, an effective PN mitigation scheme enables a PN corrupted OFDM system to function with small subcarrier spacing and......In this work, we evaluate the performance of the broadband millimeter-wave (mm-wave) OFDM system in the presence of phase noise (PN) of phase-locked loop based oscillator and delay spread of measured mm-wave channel. It is shown, using Akaike's information criterion, that the channel tap......, therefore, small CP overhead, with only slight degradation of the error rate performance....

  16. Application Of CCD Camera And Computer In Interferometry

    Science.gov (United States)

    Wang, Wensheng

    1989-01-01

    In this article we have theoretically and experimentally dicussed how scanning interference fringes are automatically recorded with a ccd camera and a computer. This new measure technique can be used to any length measurement by interferomtry. As a practical example, we have automatically in real-time measured the shrinking of 2- components adhesive in a hardening process.

  17. Application of MM wave therapy in radiology

    Energy Technology Data Exchange (ETDEWEB)

    Avakian, R.S. [Inst. of Radio Physics & Electronics, Ashtarack (Argentina); Gasparyan, L.V. [Republican Medical Centre Armenia, Yerevan (Argentina)

    1995-12-31

    The authors studied the effects of MM wave electromagnetic radiation influence on patients, affected by X-ray radiation during the reparation works after Chernobyl nuclear power plant exposure. They compared results of treatment of two groups of patients: (1) control group patients received only basis therapy; (2) testing group, 10 patients received basis therapy and MM wave influence. The authors used the wide band noise generator `Artsakh - 2` for local irradiation on the acupuncture points. Their data proved that low intensity MM waves have immunocorrective, antioxidant effects, and MM wave therapy is a perspective method for treatment of patients with radiological pathology.

  18. STS-52 MS Shepherd during camera equipment training on JSC's Bldg 1 rooftop

    Science.gov (United States)

    1992-01-01

    STS-52 Columbia, Orbiter Vehicle (OV) 102, Mission Specialist (MS) William M. Shepherd aims a 35mm camera at a distant subject from his vantage point atop the roof of JSC's nine-story Project Management Building Bldg 1. The training session familiarized Shepherd with camera equipment to be used in Earth observation documentation during STS-52.

  19. How long is enough to detect terrestrial animals? Estimating the minimum trapping effort on camera traps

    Directory of Open Access Journals (Sweden)

    Xingfeng Si

    2014-05-01

    Full Text Available Camera traps is an important wildlife inventory tool for estimating species diversity at a site. Knowing what minimum trapping effort is needed to detect target species is also important to designing efficient studies, considering both the number of camera locations, and survey length. Here, we take advantage of a two-year camera trapping dataset from a small (24-ha study plot in Gutianshan National Nature Reserve, eastern China to estimate the minimum trapping effort actually needed to sample the wildlife community. We also evaluated the relative value of adding new camera sites or running cameras for a longer period at one site. The full dataset includes 1727 independent photographs captured during 13,824 camera days, documenting 10 resident terrestrial species of birds and mammals. Our rarefaction analysis shows that a minimum of 931 camera days would be needed to detect the resident species sufficiently in the plot, and c. 8700 camera days to detect all 10 resident species. In terms of detecting a diversity of species, the optimal sampling period for one camera site was c. 40, or long enough to record about 20 independent photographs. Our analysis of evaluating the increasing number of additional camera sites shows that rotating cameras to new sites would be more efficient for measuring species richness than leaving cameras at fewer sites for a longer period.

  20. How long is enough to detect terrestrial animals? Estimating the minimum trapping effort on camera traps.

    Science.gov (United States)

    Si, Xingfeng; Kays, Roland; Ding, Ping

    2014-01-01

    Camera traps is an important wildlife inventory tool for estimating species diversity at a site. Knowing what minimum trapping effort is needed to detect target species is also important to designing efficient studies, considering both the number of camera locations, and survey length. Here, we take advantage of a two-year camera trapping dataset from a small (24-ha) study plot in Gutianshan National Nature Reserve, eastern China to estimate the minimum trapping effort actually needed to sample the wildlife community. We also evaluated the relative value of adding new camera sites or running cameras for a longer period at one site. The full dataset includes 1727 independent photographs captured during 13,824 camera days, documenting 10 resident terrestrial species of birds and mammals. Our rarefaction analysis shows that a minimum of 931 camera days would be needed to detect the resident species sufficiently in the plot, and c. 8700 camera days to detect all 10 resident species. In terms of detecting a diversity of species, the optimal sampling period for one camera site was c. 40, or long enough to record about 20 independent photographs. Our analysis of evaluating the increasing number of additional camera sites shows that rotating cameras to new sites would be more efficient for measuring species richness than leaving cameras at fewer sites for a longer period.

  1. The GCT camera for the Cherenkov Telescope Array

    Science.gov (United States)

    Lapington, J. S.; Abchiche, A.; Allan, D.; Amans, J.-P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J.-J.; Bose, R.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Buckley, J.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Daniel, M. K.; De Franco, A.; De Frondat, F.; Dournaux, J.-L.; Dumas, D.; Ernenwein, J.-P.; Fasola, G.; Funk, S.; Gironnet, J.; Graham, J. A.; Greenshaw, T.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J.-M.; Jankowsky, D.; Jegouzo, I.; Jogler, T.; Kawashima, T.; Kraus, M.; Laporte, P.; Leach, S.; Lefaucheur, J.; Markoff, S.; Melse, T.; Minaya, I. A.; Mohrmann, L.; Molyneux, P.; Moore, P.; Nolan, S. J.; Okumura, A.; Osborne, J. P.; Parsons, R. D.; Rosen, S.; Ross, D.; Rowell, G.; Rulten, C. B.; Sato, Y.; Sayede, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Sol, H.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Trichard, C.; Varner, G.; Vink, J.; Watson, J. J.; White, R.; Yamane, N.; Zech, A.; Zink, A.; Zorn, J.; CTA Consortium

    2017-12-01

    The Gamma Cherenkov Telescope (GCT) is one of the designs proposed for the Small Sized Telescope (SST) section of the Cherenkov Telescope Array (CTA). The GCT uses dual-mirror optics, resulting in a compact telescope with good image quality and a large field of view with a smaller, more economical, camera than is achievable with conventional single mirror solutions. The photon counting GCT camera is designed to record the flashes of atmospheric Cherenkov light from gamma and cosmic ray initiated cascades, which last only a few tens of nanoseconds. The GCT optics require that the camera detectors follow a convex surface with a radius of curvature of 1 m and a diameter of 35 cm, which is approximated by tiling the focal plane with 32 modules. The first camera prototype is equipped with multi-anode photomultipliers, each comprising an 8×8 array of 6×6 mm2 pixels to provide the required angular scale, adding up to 2048 pixels in total. Detector signals are shaped, amplified and digitised by electronics based on custom ASICs that provide digitisation at 1 GSample/s. The camera is self-triggering, retaining images where the focal plane light distribution matches predefined spatial and temporal criteria. The electronics are housed in the liquid-cooled, sealed camera enclosure. LED flashers at the corners of the focal plane provide a calibration source via reflection from the secondary mirror. The first GCT camera prototype underwent preliminary laboratory tests last year. In November 2015, the camera was installed on a prototype GCT telescope (SST-GATE) in Paris and was used to successfully record the first Cherenkov light of any CTA prototype, and the first Cherenkov light seen with such a dual-mirror optical system. A second full-camera prototype based on Silicon Photomultipliers is under construction. Up to 35 GCTs are envisaged for CTA.

  2. Robust Calibration of Cameras with Telephoto Lens Using Regularized Least Squares

    Directory of Open Access Journals (Sweden)

    Mingpei Liang

    2014-01-01

    Full Text Available Cameras with telephoto lens are usually used to recover details of an object that is either small or located far away from the cameras. However, the calibration of this kind of cameras is not as accurate as the one of cameras with short focal lengths that are commonly used in many vision applications. This paper has two contributions. First, we present a first-order error analysis that shows the relation between focal length and estimation uncertainties of camera parameters. To our knowledge, this error analysis with respect to focal length has not been studied in the area of camera calibration. Second, we propose a robust algorithm to calibrate the camera with a long focal length without using additional devices. By adding a regularization term, our algorithm makes the estimation of the image of the absolute conic well posed. As a consequence, the covariance of camera parameters can be reduced greatly. We further used simulations and real data to verify our proposed algorithm and obtained very stable results.

  3. The Eye of the Camera

    NARCIS (Netherlands)

    van Rompay, Thomas Johannes Lucas; Vonk, Dorette J.; Fransen, M.L.

    2009-01-01

    This study addresses the effects of security cameras on prosocial behavior. Results from previous studies indicate that the presence of others can trigger helping behavior, arising from the need for approval of others. Extending these findings, the authors propose that security cameras can likewise

  4. The outer vactank, an object of 7.6m diameter and 13m length is built up of three cylindrical parts. The central part that is integral part of the central barrel and the the extension on either side each one 4.5m long. These extensions house the shoulders that will support and prestress the CMS Coil. To weld the extensions onto the central part a full penetration weld of 24m length and 45 mm thickness has to be done by hand from inside and outside the vacuum tank and its deformation is controled permanently.

    CERN Multimedia

    Hubert Gerwig

    2001-01-01

    The outer vacuum tank will hold the coil suspension system and transmits the weight of the inner detectors to the central barrel. Its thickness is staggered. In the central part its thickness is 60 mm and then goes down to 30 mm at the extremity.

  5. Gamma camera system

    International Nuclear Information System (INIS)

    Miller, D.W.; Gerber, M.S.

    1982-01-01

    The invention provides a composite solid state detector for use in deriving a display, by spatial coordinate information, of the distribution or radiation emanating from a source within a region of interest, comprising several solid state detector components, each having a given surface arranged for exposure to impinging radiation and exhibiting discrete interactions therewith at given spatially definable locations. The surface of each component and the surface disposed opposite and substantially parallel thereto are associated with impedence means configured to provide for each opposed surface outputs for signals relating the given location of the interactions with one spatial coordinate parameter of one select directional sense. The detector components are arranged to provide groupings of adjacently disposed surfaces mutually linearly oriented to exhibit a common directional sense of the spatial coordinate parameter. Means interconnect at least two of the outputs associated with each of the surfaces within a given grouping for collecting the signals deriving therefrom. The invention also provides a camera system for imaging the distribution of a source of gamma radiation situated within a region of interest

  6. TWO METHODS FOR SELF CALIBRATION OF DIGITAL CAMERA

    Directory of Open Access Journals (Sweden)

    A. Sampath

    2012-07-01

    Full Text Available Photogrammetric mapping using Commercial of the Shelf (COTS cameras is becoming more popular. Their popularity is augmented by the increasing use of Unmanned Aerial Vehicles (UAV as a platform for mapping. The mapping precision of these methods can be increased by using a calibrated camera. The USGS/EROS has developed an inexpensive, easy to use method, particularly for calibrating short focal length cameras. The method builds on a self-calibration procedure developed for the USGS EROS Data Center by Pictometry (and augmented by Dr. C.S Fraser, that uses a series of coded targets. These coded targets form different patterns that are imaged from nine different locations with differing camera orientations. A free network solution using collinearity equations is used to determine the calibration parameters. For the smaller focal length COTS cameras, the USGS has developed a procedure that uses a small prototype box that contains these coded targets. The design of the box is discussed, along with best practices for calibration procedure. Results of calibration parameters obtained using the box are compared with the parameters obtained using more established standard procedures.

  7. Mandibular Overdentures Supported by 6-mm Dental Implants : A 1-Year Prospective Cohort Study

    NARCIS (Netherlands)

    Gulje, Felix; Raghoebar, Gerry M.; Ter Meulen, Jan-Willem P.; Vissink, Arjan; Meijer, Henny J. A.; Guljé, Felix

    Background: The extremely resorbed edentulous mandible, with a bone height of 8 mm or less, is still a challenge in implant dentistry. Recently, dental implants of 6 mm in length have been developed. Purpose: The purpose of this 1-year prospective cohort study was to evaluate treatment outcome of

  8. Rapid objective measurement of gamma camera resolution using statistical moments.

    Science.gov (United States)

    Hander, T A; Lancaster, J L; Kopp, D T; Lasher, J C; Blumhardt, R; Fox, P T

    1997-02-01

    An easy and rapid method for the measurement of the intrinsic spatial resolution of a gamma camera was developed. The measurement is based on the first and second statistical moments of regions of interest (ROIs) applied to bar phantom images. This leads to an estimate of the modulation transfer function (MTF) and the full-width-at-half-maximum (FWHM) of a line spread function (LSF). Bar phantom images were acquired using four large field-of-view (LFOV) gamma cameras (Scintronix, Picker, Searle, Siemens). The following factors important for routine measurements of gamma camera resolution with this method were tested: ROI placement and shape, phantom orientation, spatial sampling, and procedural consistency. A 0.2% coefficient of variation (CV) between repeat measurements of MTF was observed for a circular ROI. The CVs of less than 2% were observed for measured MTF values for bar orientations ranging from -10 degrees to +10 degrees with respect to the x and y axes of the camera acquisition matrix. A 256 x 256 matrix (1.6 mm pixel spacing) was judged sufficient for routine measurements, giving an estimate of the FWHM to within 0.1 mm of manufacturer-specified values (3% difference). Under simulated clinical conditions, the variation in measurements attributable to procedural effects yielded a CV of less than 2% in newer generation cameras. The moments method for determining MTF correlated well with a peak-valley method, with an average difference of 0.03 across the range of spatial frequencies tested (0.11-0.17 line pairs/mm, corresponding to 4.5-3.0 mm bars). When compared with the NEMA method for measuring intrinsic spatial resolution, the moments method was found to be within 4% of the expected FWHM.

  9. QM/MM methods in inorganic chemistry.

    Science.gov (United States)

    Bo, Carles; Maseras, Feliu

    2008-06-14

    Quantum mechanics/molecular mechanics (QM/MM) methods are a useful tool for the computational study of inorganic systems. They allow a quantitative description of systems larger than those treatable with pure QM methods, in principle with a comparable quality. QM/MM calculations are being currently applied to the research in a variety of topics, including structural effects of ligand bulk, selectivity in homogeneous catalysis and mechanical embedding in heterogeneous catalysis. The QM/MM approach is also useful for the separation of steric and electronic contributions, and as an auxiliary tool for geometry optimization when full QM methods are mandatory. The power of QM/MM methods in inorganic chemistry is illustrated in this Perspective with a summary of recent representative applications.

  10. MM Algorithms for Geometric and Signomial Programming.

    Science.gov (United States)

    Lange, Kenneth; Zhou, Hua

    2014-02-01

    This paper derives new algorithms for signomial programming, a generalization of geometric programming. The algorithms are based on a generic principle for optimization called the MM algorithm. In this setting, one can apply the geometric-arithmetic mean inequality and a supporting hyperplane inequality to create a surrogate function with parameters separated. Thus, unconstrained signomial programming reduces to a sequence of one-dimensional minimization problems. Simple examples demonstrate that the MM algorithm derived can converge to a boundary point or to one point of a continuum of minimum points. Conditions under which the minimum point is unique or occurs in the interior of parameter space are proved for geometric programming. Convergence to an interior point occurs at a linear rate. Finally, the MM framework easily accommodates equality and inequality constraints of signomial type. For the most important special case, constrained quadratic programming, the MM algorithm involves very simple updates.

  11. Magnetometer Data recovered from 35mm film

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The L57 CDMP recovery project takes magnetometer data on 35mm film stored at the archive's climate controlled warehouse and digitizes them.

  12. Titanium Socket for 120 mm Mortar Base

    National Research Council Canada - National Science Library

    2004-01-01

    The U.S. Army's Armament Research, Development, and Engineering Center (ARDEC) at Picatinny Arsenal in Rockaway Township, New Jersey, was commissioned to reduce the weight of the base for the 120mm mortar...

  13. CCD TV camera, TM1300

    International Nuclear Information System (INIS)

    Takano, Mitsuo; Endou, Yukio; Nakayama, Hideo

    1982-01-01

    Development has been made of a black-and-white TV camera TM 1300 using an interline-transfer CCD, which excels in performance frame-transfer CCDs marketed since 1980: it has a greater number of horizontal picture elements and far smaller input power (less than 2 W at 9 V), uses hybrid ICs for the CCD driver unit to reduce the size of the camera, has no picture distortion, no burn-in; in addition, it has peripheral equipment, such as the camera housing and the pan and till head miniaturized as well. It is also expected to be widened in application to industrial TV. (author)

  14. High Quality Camera Surveillance System

    OpenAIRE

    Helaakoski, Ari

    2015-01-01

    Oulu University of Applied Sciences Information Technology Author: Ari Helaakoski Title of the master’s thesis: High Quality Camera Surveillance System Supervisor: Kari Jyrkkä Term and year of completion: Spring 2015 Number of pages: 31 This master’s thesis was commissioned by iProtoXi Oy and it was done to one iProtoXi customer. The aim of the thesis was to make a camera surveillance system which is using a High Quality camera with pan and tilt possibility. It should b...

  15. Control system for gamma camera

    International Nuclear Information System (INIS)

    Miller, D.W.

    1977-01-01

    An improved gamma camera arrangement is described which utilizing a solid state detector, formed of high purity germanium. the central arrangement of the camera operates to effect the carrying out of a trapezoidal filtering operation over antisymmetrically summed spatial signals through gated integration procedures utilizing idealized integrating intervals. By simultaneously carrying out peak energy evaluation of the input signals, a desirable control over pulse pile-up phenomena is achieved. Additionally, through the use of the time derivative of incoming pulse or signal energy information to initially enable the control system, a low level information evaluation is provided serving to enhance the signal processing efficiency of the camera

  16. Camera trap arrays improve detection probability of wildlife: Investigating study design considerations using an empirical dataset.

    Directory of Open Access Journals (Sweden)

    Kelly M O'Connor

    Full Text Available Camera trapping is a standard tool in ecological research and wildlife conservation. Study designs, particularly for small-bodied or cryptic wildlife species often attempt to boost low detection probabilities by using non-random camera placement or baited cameras, which may bias data, or incorrectly estimate detection and occupancy. We investigated the ability of non-baited, multi-camera arrays to increase detection probabilities of wildlife. Study design components were evaluated for their influence on wildlife detectability by iteratively parsing an empirical dataset (1 by different sizes of camera arrays deployed (1-10 cameras, and (2 by total season length (1-365 days. Four species from our dataset that represented a range of body sizes and differing degrees of presumed detectability based on life history traits were investigated: white-tailed deer (Odocoileus virginianus, bobcat (Lynx rufus, raccoon (Procyon lotor, and Virginia opossum (Didelphis virginiana. For all species, increasing from a single camera to a multi-camera array significantly improved detection probability across the range of season lengths and number of study sites evaluated. The use of a two camera array increased survey detection an average of 80% (range 40-128% from the detection probability of a single camera across the four species. Species that were detected infrequently benefited most from a multiple-camera array, where the addition of up to eight cameras produced significant increases in detectability. However, for species detected at high frequencies, single cameras produced a season-long (i.e, the length of time over which cameras are deployed and actively monitored detectability greater than 0.75. These results highlight the need for researchers to be critical about camera trap study designs based on their intended target species, as detectability for each focal species responded differently to array size and season length. We suggest that researchers a priori

  17. Camera trap arrays improve detection probability of wildlife: Investigating study design considerations using an empirical dataset.

    Science.gov (United States)

    O'Connor, Kelly M; Nathan, Lucas R; Liberati, Marjorie R; Tingley, Morgan W; Vokoun, Jason C; Rittenhouse, Tracy A G

    2017-01-01

    Camera trapping is a standard tool in ecological research and wildlife conservation. Study designs, particularly for small-bodied or cryptic wildlife species often attempt to boost low detection probabilities by using non-random camera placement or baited cameras, which may bias data, or incorrectly estimate detection and occupancy. We investigated the ability of non-baited, multi-camera arrays to increase detection probabilities of wildlife. Study design components were evaluated for their influence on wildlife detectability by iteratively parsing an empirical dataset (1) by different sizes of camera arrays deployed (1-10 cameras), and (2) by total season length (1-365 days). Four species from our dataset that represented a range of body sizes and differing degrees of presumed detectability based on life history traits were investigated: white-tailed deer (Odocoileus virginianus), bobcat (Lynx rufus), raccoon (Procyon lotor), and Virginia opossum (Didelphis virginiana). For all species, increasing from a single camera to a multi-camera array significantly improved detection probability across the range of season lengths and number of study sites evaluated. The use of a two camera array increased survey detection an average of 80% (range 40-128%) from the detection probability of a single camera across the four species. Species that were detected infrequently benefited most from a multiple-camera array, where the addition of up to eight cameras produced significant increases in detectability. However, for species detected at high frequencies, single cameras produced a season-long (i.e, the length of time over which cameras are deployed and actively monitored) detectability greater than 0.75. These results highlight the need for researchers to be critical about camera trap study designs based on their intended target species, as detectability for each focal species responded differently to array size and season length. We suggest that researchers a priori identify

  18. Fabry-Perot interferometry using an image-intensified rotating-mirror streak camera

    International Nuclear Information System (INIS)

    Seitz, W.L.; Stacy, H.L.

    1983-01-01

    A Fabry-Perot velocity interferometer system is described that uses a modified rotating mirror streak camera to recrod the dynamic fringe positions. A Los Alamos Model 72B rotating-mirror streak camera, equipped with a beryllium mirror, was modified to include a high aperture (f/2.5) relay lens and a 40-mm image-intensifier tube such that the image normally formed at the film plane of the streak camera is projected onto the intensifier tube. Fringe records for thin (0.13 mm) flyers driven by a small bridgewire detonator obtained with a Model C1155-01 Hamamatsu and Model 790 Imacon electronic streak cameras are compared with those obtained with the image-intensified rotating-mirror streak camera (I 2 RMC). Resolution comparisons indicate that the I 2 RMC gives better time resolution than either the Hamamatsu or the Imacon for total writing times of a few microseconds or longer

  19. Development of a high resolution gamma camera system using finely grooved GAGG scintillator

    Science.gov (United States)

    Yamamoto, Seiichi; Kataoka, Jun; Oshima, Tsubasa; Ogata, Yoshimune; Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu; Hatazawa, Jun

    2016-06-01

    High resolution gamma cameras require small pixel scintillator blocks with high light output. However, manufacturing a small pixel scintillator block is difficult when the pixel size becomes small. To solve this limitation, we developed a high resolution gamma camera system using a finely grooved Ce-doped Gd3Al2Ga3O12 (GAGG) plate. Our gamma camera's detector consists of a 1-mm-thick finely grooved GAGG plate that is optically coupled to a 1-in. position sensitive photomultiplier tube (PSPMT). The grooved GAGG plate has 0.2×0.2 mm pixels with 0.05-mm wide slits (between the pixels) that were manufactured using a dicing saw. We used a Hamamatsu PSPMT with a 1-in. square high quantum efficiency (HQE) PSPMT (R8900-100-C12). The energy resolution for the Co-57 gamma photons (122 keV) was 18.5% FWHM. The intrinsic spatial resolution was estimated to be 0.7-mm FWHM. With a 0.5-mm diameter pinhole collimator mounted to its front, we achieved a high resolution, small field-of-view gamma camera. The system spatial resolution for the Co-57 gamma photons was 1.0-mm FWHM, and the sensitivity was 0.0025%, 10 mm from the collimator surface. The Tc-99m HMDP administered mouse images showed the fine structures of the mouse body's parts. Our developed high resolution small pixel GAGG gamma camera is promising for such small animal imaging.

  20. Multi-Angle Snowflake Camera Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Shkurko, Konstantin [Univ. of Utah, Salt Lake City, UT (United States); Garrett, T. [Univ. of Utah, Salt Lake City, UT (United States); Gaustad, K [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-12-01

    The Multi-Angle Snowflake Camera (MASC) addresses a need for high-resolution multi-angle imaging of hydrometeors in freefall with simultaneous measurement of fallspeed. As illustrated in Figure 1, the MASC consists of three cameras, separated by 36°, each pointing at an identical focal point approximately 10 cm away. Located immediately above each camera, a light aims directly at the center of depth of field for its corresponding camera. The focal point at which the cameras are aimed lies within a ring through which hydrometeors fall. The ring houses a system of near-infrared emitter-detector pairs, arranged in two arrays separated vertically by 32 mm. When hydrometeors pass through the lower array, they simultaneously trigger all cameras and lights. Fallspeed is calculated from the time it takes to traverse the distance between the upper and lower triggering arrays. The trigger electronics filter out ambient light fluctuations associated with varying sunlight and shadows. The microprocessor onboard the MASC controls the camera system and communicates with the personal computer (PC). The image data is sent via FireWire 800 line, and fallspeed (and camera control) is sent via a Universal Serial Bus (USB) line that relies on RS232-over-USB serial conversion. See Table 1 for specific details on the MASC located at the Oliktok Point Mobile Facility on the North Slope of Alaska. The value-added product (VAP) detailed in this documentation analyzes the raw data (Section 2.0) using Python: images rely on OpenCV image processing library and derived aggregated statistics rely on some clever averaging. See Sections 4.1 and 4.2 for more details on what variables are computed.

  1. Kidney Length in Normal Korean Children

    International Nuclear Information System (INIS)

    Kim, In One; Cheon, Jung Eun; Lee, Young Seok; Lee, Sun Wha; Kim, Ok Hwa; Kim, Ji Hye; Kim, Hong Dae; Sim, Jung Suk

    2010-01-01

    Renal length offers important information to detect or follow-up various renal diseases. The purpose of this study was to determine the kidney length of normal Korean children in relation to age, height, weight, body surface area (BSA), and body mass index (BMI). Children between 1 month and 15 years of age without urological abnormality were recruited. Children below 3rd percentile and over 97th percentile for height or weight were excluded. Both renal lengths were measured in the prone position three times and then averaged by experienced radiologists. The mean length and standard deviation for each age group was obtained, and regression equation was calculated between renal length and age, weight, height, BSA, and BMI, respectively. Renal length was measured in 550 children. Renal length grows rapidly until 24 month, while the growth rate is reduced thereafter. The regression equation for age is: renal length (mm) = 45.953 + 1.064 x age (month, ≤ 24 months) (R2 = 0.720) or 62.173 + 0.203 x age (months, > 24 months) (R2 = 0.711). The regression equation for height is: renal length (mm) = 24.494 + 0.457 x height (cm) (R2 = 0.894). The regression equation for weight is: renal length (mm) = 38.342 + 2.117 x weight (kg, ≤18 kg) (R2 = 0.852) or 64.498 + 0.646 x weight (kg, > 18 kg) (R2 = 0.651). The regression equation for BSA is: renal length (mm) = 31.622 + 61.363 x BSA (m2, ≤ 0.7) (R2 = 0.857) or 52.717 + 29.959 x BSA (m2, > 0.7) (R2 = 0.715). The regression equation for BMI is: renal length (mm) = 44.474 + 1.163 x BMI (R2 = 0.079). This study provides data on the normal renal length and its association with age, weight, height, BSA and BMI. The results of this study will guide the detection and follow-up of renal diseases in Korean children

  2. DEFINITION LENS DISTORTION CAMERA WHEN PHOTOGRAMMETRIC IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    S. N. Mamedbekov

    2014-01-01

    Full Text Available In this paper we consider the classical method of calculating the magnitude of the distortion, and the account of its impact on the offset image points on the field image. Made a priori estimate of the impact of distortion for lenses with focal lengths of 55 mm and 140 mm. Results given graphically. 

  3. Analyzer for gamma cameras diagnostic

    International Nuclear Information System (INIS)

    Oramas Polo, I.; Osorio Deliz, J. F.; Diaz Garcia, A.

    2013-01-01

    This research work was carried out to develop an analyzer for gamma cameras diagnostic. It is composed of an electronic system that includes hardware and software capabilities, and operates from the acquisition of the 4 head position signals of a gamma camera detector. The result is the spectrum of the energy delivered by nuclear radiation coming from the camera detector head. This system includes analog processing of position signals from the camera, digitization and the subsequent processing of the energy signal in a multichannel analyzer, sending data to a computer via a standard USB port and processing of data in a personal computer to obtain the final histogram. The circuits are composed of an analog processing board and a universal kit with micro controller and programmable gate array. (Author)

  4. New generation of meteorology cameras

    Science.gov (United States)

    Janout, Petr; Blažek, Martin; Páta, Petr

    2017-12-01

    A new generation of the WILLIAM (WIde-field aLL-sky Image Analyzing Monitoring system) camera includes new features such as monitoring of rain and storm clouds during the day observation. Development of the new generation of weather monitoring cameras responds to the demand for monitoring of sudden weather changes. However, new WILLIAM cameras are ready to process acquired image data immediately, release warning against sudden torrential rains, and send it to user's cell phone and email. Actual weather conditions are determined from image data, and results of image processing are complemented by data from sensors of temperature, humidity, and atmospheric pressure. In this paper, we present the architecture, image data processing algorithms of mentioned monitoring camera and spatially-variant model of imaging system aberrations based on Zernike polynomials.

  5. Real-time single-shot electron bunch length measurements

    CERN Document Server

    Wilke, I; Gillespie, W A; Berden, G; Knippels, G M H; Meer, A F G

    2002-01-01

    Linear accelerators employed as drivers for X-ray free electron lasers (FELs) require relativistic electron bunch with sub-picosecond bunch length. Precise bunch length measurements are important for the tuning and operation of the FELs. Previously, we have demonstrated that electro-optic detection is a powerful technique for sub-picosecond electron bunch length measurements. In those experiments, the measured bunch length was the average of all electron bunches within a macropulse. Here, for the first time, we present the measurement of the length of individual electron bunches using a development of our previous technique. In this experiment, the longitudinal electron bunch shape is encoded electro-optically on to the frequency spectrum of a chirped laser pulse. Subsequently, the laser pulse is dispersed by a grating and the spectrum is imaged with a CCD camera. Single bunch measurements are achieved by using a nanosecond gated camera, and synchronizing the gate with both the electron bunch and the laser pu...

  6. Towards the Influence of a CAR Windshield on Depth Calculation with a Stereo Camera System

    Science.gov (United States)

    Hanel, A.; Hoegner, L.; Stilla, U.

    2016-06-01

    Stereo camera systems in cars are often used to estimate the distance of other road users from the car. This information is important to improve road safety. Such camera systems are typically mounted behind the windshield of the car. In this contribution, the influence of the windshield on the estimated distance values is analyzed. An offline stereo camera calibration is performed with a moving planar calibration target. In a standard procedure bundle adjustment, the relative orientation of the cameras is estimated. The calibration is performed for the identical stereo camera system with and without a windshield in between. The base lengths are derived from the relative orientation in both cases and are compared. Distance values are calculated and analyzed. It can be shown, that the difference of the base length values in the two cases is highly significant. Resulting effects on the distance calculation up to a half meter occur.

  7. Astronomy and the camera obscura

    Science.gov (United States)

    Feist, M.

    2000-02-01

    The camera obscura (from Latin meaning darkened chamber) is a simple optical device with a long history. In the form considered here, it can be traced back to 1550. It had its heyday during the Victorian era when it was to be found at the seaside as a tourist attraction or sideshow. It was also used as an artist's drawing aid and, in 1620, the famous astronomer-mathematician, Johannes Kepler used a small tent camera obscura to trace the scenery.

  8. Multi-camera synchronization core implemented on USB3 based FPGA platform

    Science.gov (United States)

    Sousa, Ricardo M.; Wäny, Martin; Santos, Pedro; Dias, Morgado

    2015-03-01

    Centered on Awaiba's NanEye CMOS image sensor family and a FPGA platform with USB3 interface, the aim of this paper is to demonstrate a new technique to synchronize up to 8 individual self-timed cameras with minimal error. Small form factor self-timed camera modules of 1 mm x 1 mm or smaller do not normally allow external synchronization. However, for stereo vision or 3D reconstruction with multiple cameras as well as for applications requiring pulsed illumination it is required to synchronize multiple cameras. In this work, the challenge of synchronizing multiple selftimed cameras with only 4 wire interface has been solved by adaptively regulating the power supply for each of the cameras. To that effect, a control core was created to constantly monitor the operating frequency of each camera by measuring the line period in each frame based on a well-defined sampling signal. The frequency is adjusted by varying the voltage level applied to the sensor based on the error between the measured line period and the desired line period. To ensure phase synchronization between frames, a Master-Slave interface was implemented. A single camera is defined as the Master, with its operating frequency being controlled directly through a PC based interface. The remaining cameras are setup in Slave mode and are interfaced directly with the Master camera control module. This enables the remaining cameras to monitor its line and frame period and adjust their own to achieve phase and frequency synchronization. The result of this work will allow the implementation of smaller than 3mm diameter 3D stereo vision equipment in medical endoscopic context, such as endoscopic surgical robotic or micro invasive surgery.

  9. Science, conservation, and camera traps

    Science.gov (United States)

    Nichols, James D.; Karanth, K. Ullas; O'Connel, Allan F.; O'Connell, Allan F.; Nichols, James D.; Karanth, K. Ullas

    2011-01-01

    Biologists commonly perceive camera traps as a new tool that enables them to enter the hitherto secret world of wild animals. Camera traps are being used in a wide range of studies dealing with animal ecology, behavior, and conservation. Our intention in this volume is not to simply present the various uses of camera traps, but to focus on their use in the conduct of science and conservation. In this chapter, we provide an overview of these two broad classes of endeavor and sketch the manner in which camera traps are likely to be able to contribute to them. Our main point here is that neither photographs of individual animals, nor detection history data, nor parameter estimates generated from detection histories are the ultimate objective of a camera trap study directed at either science or management. Instead, the ultimate objectives are best viewed as either gaining an understanding of how ecological systems work (science) or trying to make wise decisions that move systems from less desirable to more desirable states (conservation, management). Therefore, we briefly describe here basic approaches to science and management, emphasizing the role of field data and associated analyses in these processes. We provide examples of ways in which camera trap data can inform science and management.

  10. Radial variation in fiber length of some lesser used wood species in ...

    African Journals Online (AJOL)

    Variations in fibre length of ten lesser used wood species were investigated. The mean fibre length varied from 1.07mm in Lannea acida to 2.41mm in Sterculia setigera. Four patterns of within tree radial variations in fibre length were observed in the studied species. In pattern one, fibre length increased from the pith to the ...

  11. An ISPA-camera for gamma rays

    CERN Document Server

    Puertolas, D; Pani, R; Leutz, H; Gys, Thierry; De Notaristefani, F; D'Ambrosio, C

    1995-01-01

    With the recently developed ISPA (Imaging Silicon Pixel Array)-tube attached either to a planar YAlO3(Ce) (YAP) disc (1mm thick) or to a matrix of optically-separated YAP-crystals (5mm high, 0.6 x 0.6 mm2 cross-section) we achieved high spatial resolution of 57Co-122 keV photons. The vacuum-sealed ISPA-tube is only 4 cm long with 3.5 cm diameter and consists of a photocathode viewed at 3 cm distance by a silicon pixel chip, directly detecting the photoelectrons. The chip-anode consists of 1024 rectangular pixels with 75 µm x 500 µm edges, each bump-bonded to their individual front-end electronics. The total pixel array read-out time is 10 µs. The measured intrinsic spatial resolutions (FWHM) of this ISPA-camera are 700 µm (planar YAP) and 310 µm (YAP-matrix). Apart from its already demonstrated application for particle tracking with scintillating fibres, the ISPA-tube provides also an excellent tool in medicine, biology and chemistry.

  12. IMAGE ACQUISITION CONSTRAINTS FOR PANORAMIC FRAME CAMERA IMAGING

    Directory of Open Access Journals (Sweden)

    H. Kauhanen

    2012-07-01

    Full Text Available The paper describes an approach to quantify the amount of projective error produced by an offset of projection centres in a panoramic imaging workflow. We have limited this research to such panoramic workflows in which several sub-images using planar image sensor are taken and then stitched together as a large panoramic image mosaic. The aim is to simulate how large the offset can be before it introduces significant error to the dataset. The method uses geometrical analysis to calculate the error in various cases. Constraints for shooting distance, focal length and the depth of the area of interest are taken into account. Considering these constraints, it is possible to safely use even poorly calibrated panoramic camera rig with noticeable offset in projection centre locations. The aim is to create datasets suited for photogrammetric reconstruction. Similar constraints can be used also for finding recommended areas from the image planes for automatic feature matching and thus improve stitching of sub-images into full panoramic mosaics. The results are mainly designed to be used with long focal length cameras where the offset of projection centre of sub-images can seem to be significant but on the other hand the shooting distance is also long. We show that in such situations the error introduced by the offset of the projection centres results only in negligible error when stitching a metric panorama. Even if the main use of the results is with cameras of long focal length, they are feasible for all focal lengths.

  13. Development of high resolution camera for observations of superconducting cavities

    Directory of Open Access Journals (Sweden)

    Yoshihisa Iwashita

    2008-09-01

    Full Text Available A system for inspecting the inner surface of superconducting rf cavities is developed in order to study the relation between the achievable field gradient and the defects in the inner surface. The inspection system consists of a high resolution complementary metal-oxide-semiconductor camera and a special illumination system built in a cylinder that has a diameter of 50 mm. The camera cylinder can be inserted into the L-band 9 cell superconducting cavity. The system provides a resolution of about 7.5  μm/pixel. Thus far, there have been good correlations between locations identified by thermometry measurements and positions of defects found by this system. The heights or depths of the defects can also be estimated by measuring wall gradients using the reflection angle relation between the camera position and the strip illumination position. This paper presents a detailed description of the system and the data obtained from it.

  14. Microeconomics of 300-mm process module control

    Science.gov (United States)

    Monahan, Kevin M.; Chatterjee, Arun K.; Falessi, Georges; Levy, Ady; Stoller, Meryl D.

    2001-08-01

    Simple microeconomic models that directly link metrology, yield, and profitability are rare or non-existent. In this work, we validate and apply such a model. Using a small number of input parameters, we explain current yield management practices in 200 mm factories. The model is then used to extrapolate requirements for 300 mm factories, including the impact of simultaneous technology transitions to 130nm lithography and integrated metrology. To support our conclusions, we use examples relevant to factory-wide photo module control.

  15. Gain attenuation of gated framing camera

    International Nuclear Information System (INIS)

    Xiao Shali; Liu Shenye; Cao Zhurong; Li Hang; Zhang Haiying; Yuan Zheng; Wang Liwei

    2009-01-01

    The theoretic model of framing camera's gain attenuation is analyzed. The exponential attenuation curve of the gain along the pulse propagation time is simulated. An experiment to measure the coefficient of gain attenuation based on the gain attenuation theory is designed. Experiment result shows that the gain follows an exponential attenuation rule with a quotient of 0.0249 nm -1 , the attenuation coefficient of the pulse is 0.00356 mm -1 . The loss of the pulse propagation along the MCP stripline is the leading reason of gain attenuation. But in the figure of a single stripline, the gain dose not follow the rule of exponential attenuation completely, instead, there is a gain increase at the stripline bottom. That is caused by the reflection of the pulse. The reflectance is about 24.2%. Combining the experiment and theory, which design of the stripline MCP can improved the gain attenuation. (authors)

  16. Camera Embedded Single Lumen Tube as a Rescue Device for Airway Handling during Lung Separation

    DEFF Research Database (Denmark)

    Højberg Holm, Jimmy; Andersen, Claus

    2016-01-01

    endotracheal tube (SLT, ID 7.0 mm, OD 10.0 mm) with embedded camera (VivaSight-SLTM, ET-View Ltd, Misgav, Israel) (Figure 1), and with this secured in the trachea, lung isolation was obtained with the use of an bronchial blocker (VivaSight-EB, 9 Fr) on the left side, resulting in total lung collapse, allowing...

  17. Hyper Suprime-Cam: Camera dewar design

    Science.gov (United States)

    Komiyama, Yutaka; Obuchi, Yoshiyuki; Nakaya, Hidehiko; Kamata, Yukiko; Kawanomoto, Satoshi; Utsumi, Yousuke; Miyazaki, Satoshi; Uraguchi, Fumihiro; Furusawa, Hisanori; Morokuma, Tomoki; Uchida, Tomohisa; Miyatake, Hironao; Mineo, Sogo; Fujimori, Hiroki; Aihara, Hiroaki; Karoji, Hiroshi; Gunn, James E.; Wang, Shiang-Yu

    2018-01-01

    This paper describes the detailed design of the CCD dewar and the camera system which is a part of the wide-field imager Hyper Suprime-Cam (HSC) on the 8.2 m Subaru Telescope. On the 1.°5 diameter focal plane (497 mm in physical size), 116 four-side buttable 2 k × 4 k fully depleted CCDs are tiled with 0.3 mm gaps between adjacent chips, which are cooled down to -100°C by two pulse tube coolers with a capability to exhaust 100 W heat at -100°C. The design of the dewar is basically a natural extension of Suprime-Cam, incorporating some improvements such as (1) a detailed CCD positioning strategy to avoid any collision between CCDs while maximizing the filling factor of the focal plane, (2) a spherical washers mechanism adopted for the interface points to avoid any deformation caused by the tilt of the interface surface to be transferred to the focal plane, (3) the employment of a truncated-cone-shaped window, made of synthetic silica, to save the back focal space, and (4) a passive heat transfer mechanism to exhaust efficiently the heat generated from the CCD readout electronics which are accommodated inside the dewar. Extensive simulations using a finite-element analysis (FEA) method are carried out to verify that the design of the dewar is sufficient to satisfy the assigned errors. We also perform verification tests using the actually assembled CCD dewar to supplement the FEA and demonstrate that the design is adequate to ensure an excellent image quality which is key to the HSC. The details of the camera system, including the control computer system, are described as well as the assembling process of the dewar and the process of installation on the telescope.

  18. Collimated trans-axial tomographic scintillation camera

    International Nuclear Information System (INIS)

    1980-01-01

    The principal problem in trans-axial tomographic radioisotope scanning is the length of time required to obtain meaningful data. Patient movement and radioisotope migration during the scanning period can cause distortion of the image. The object of this invention is to reduce the scanning time without degrading the images obtained. A system is described in which a scintillation camera detector is moved to an orbit about the cranial-caudal axis relative to the patient. A collimator is used in which lead septa are arranged so as to admit gamma rays travelling perpendicular to this axis with high spatial resolution and those travelling in the direction of the axis with low spatial resolution, thus increasing the rate of acceptance of radioactive events to contribute to the positional information obtainable without sacrificing spatial resolution. (author)

  19. The fly's eye camera system

    Science.gov (United States)

    Mészáros, L.; Pál, A.; Csépány, G.; Jaskó, A.; Vida, K.; Oláh, K.; Mezö, G.

    2014-12-01

    We introduce the Fly's Eye Camera System, an all-sky monitoring device intended to perform time domain astronomy. This camera system design will provide complementary data sets for other synoptic sky surveys such as LSST or Pan-STARRS. The effective field of view is obtained by 19 cameras arranged in a spherical mosaic form. These individual cameras of the device stand on a hexapod mount that is fully capable of achieving sidereal tracking for the subsequent exposures. This platform has many advantages. First of all it requires only one type of moving component and does not include unique parts. Hence this design not only eliminates problems implied by unique elements, but the redundancy of the hexapod allows smooth operations even if one or two of the legs are stuck. In addition, it can calibrate itself by observed stars independently from both the geographical location (including northen and southern hemisphere) and the polar alignment of the full mount. All mechanical elements and electronics are designed within the confines of our institute Konkoly Observatory. Currently, our instrument is in testing phase with an operating hexapod and reduced number of cameras.

  20. COMPARISON OF METHODS FOR GEOMETRIC CAMERA CALIBRATION

    Directory of Open Access Journals (Sweden)

    J. Hieronymus

    2012-09-01

    Full Text Available Methods for geometric calibration of cameras in close-range photogrammetry are established and well investigated. The most common one is based on test-fields with well-known pattern, which are observed from different directions. The parameters of a distortion model are calculated using bundle-block-adjustment-algorithms. This methods works well for short focal lengths, but is essentially more problematic to use with large focal lengths. Those would require very large test-fields and surrounding space. To overcome this problem, there is another common method for calibration used in remote sensing. It employs measurements using collimator and a goniometer. A third calibration method uses diffractive optical elements (DOE to project holograms of well known pattern. In this paper these three calibration methods are compared empirically, especially in terms of accuracy. A camera has been calibrated with those methods mentioned above. All methods provide a set of distortion correction parameters as used by the photogrammetric software Australis. The resulting parameter values are very similar for all investigated methods. The three sets of distortion parameters are crosscompared against all three calibration methods. This is achieved by inserting the gained distortion parameters as fixed input into the calibration algorithms and only adjusting the exterior orientation. The RMS (root mean square of the remaining image coordinate residuals are taken as a measure of distortion correction quality. There are differences resulting from the different calibration methods. Nevertheless the measure is small for every comparison, which means that all three calibration methods can be used for accurate geometric calibration.

  1. Full Length Research Article

    African Journals Online (AJOL)

    Dr Ahmed

    A total of 28 plant species visited by the honeybee Apis mellifera adansonii Latrielle were observed and collected from. September 2006-January 2008 in Zaria, Nigeria using secateur and plant presses to cut and preserve the specimens. A digital camera was used to photograph the honeybees on plants. The plants were ...

  2. Soft x-ray streak camera for laser fusion applications

    International Nuclear Information System (INIS)

    Stradling, G.L.

    1981-04-01

    This thesis reviews the development and significance of the soft x-ray streak camera (SXRSC) in the context of inertial confinement fusion energy development. A brief introduction of laser fusion and laser fusion diagnostics is presented. The need for a soft x-ray streak camera as a laser fusion diagnostic is shown. Basic x-ray streak camera characteristics, design, and operation are reviewed. The SXRSC design criteria, the requirement for a subkilovolt x-ray transmitting window, and the resulting camera design are explained. Theory and design of reflector-filter pair combinations for three subkilovolt channels centered at 220 eV, 460 eV, and 620 eV are also presented. Calibration experiments are explained and data showing a dynamic range of 1000 and a sweep speed of 134 psec/mm are presented. Sensitivity modifications to the soft x-ray streak camera for a high-power target shot are described. A preliminary investigation, using a stepped cathode, of the thickness dependence of the gold photocathode response is discussed. Data from a typical Argus laser gold-disk target experiment are shown

  3. Analyzing Gait Using a Time-of-Flight Camera

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Paulsen, Rasmus Reinhold; Larsen, Rasmus

    2009-01-01

    An algorithm is created, which performs human gait analysis using spatial data and amplitude images from a Time-of-flight camera. For each frame in a sequence the camera supplies cartesian coordinates in space for every pixel. By using an articulated model the subject pose is estimated in the depth...... map in each frame. The pose estimation is based on likelihood, contrast in the amplitude image, smoothness and a shape prior used to solve a Markov random field. Based on the pose estimates, and the prior that movement is locally smooth, a sequential model is created, and a gait analysis is done...... on this model. The output data are: Speed, Cadence (steps per minute), Step length, Stride length (stride being two consecutive steps also known as a gait cycle), and Range of motion (angles of joints). The created system produces good output data of the described output parameters and requires no user...

  4. Dark Energy Camera for Blanco

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Gary A.; /Caltech /SLAC

    2010-08-25

    In order to make accurate measurements of dark energy, a system is needed to monitor the focus and alignment of the Dark Energy Camera (DECam) to be located on the Blanco 4m Telescope for the upcoming Dark Energy Survey. One new approach under development is to fit out-of-focus star images to a point spread function from which information about the focus and tilt of the camera can be obtained. As a first test of a new algorithm using this idea, simulated star images produced from a model of DECam in the optics software Zemax were fitted. Then, real images from the Mosaic II imager currently installed on the Blanco telescope were used to investigate the algorithm's capabilities. A number of problems with the algorithm were found, and more work is needed to understand its limitations and improve its capabilities so it can reliably predict camera alignment and focus.

  5. EDICAM (Event Detection Intelligent Camera)

    Energy Technology Data Exchange (ETDEWEB)

    Zoletnik, S. [Wigner RCP RMI, EURATOM Association, Budapest (Hungary); Szabolics, T., E-mail: szabolics.tamas@wigner.mta.hu [Wigner RCP RMI, EURATOM Association, Budapest (Hungary); Kocsis, G.; Szepesi, T.; Dunai, D. [Wigner RCP RMI, EURATOM Association, Budapest (Hungary)

    2013-10-15

    Highlights: ► We present EDICAM's hardware modules. ► We present EDICAM's main design concepts. ► This paper will describe EDICAM firmware architecture. ► Operation principles description. ► Further developments. -- Abstract: A new type of fast framing camera has been developed for fusion applications by the Wigner Research Centre for Physics during the last few years. A new concept was designed for intelligent event driven imaging which is capable of focusing image readout to Regions of Interests (ROIs) where and when predefined events occur. At present these events mean intensity changes and external triggers but in the future more sophisticated methods might also be defined. The camera provides 444 Hz frame rate at full resolution of 1280 × 1024 pixels, but monitoring of smaller ROIs can be done in the 1–116 kHz range even during exposure of the full image. Keeping space limitations and the harsh environment in mind the camera is divided into a small Sensor Module and a processing card interconnected by a fast 10 Gbit optical link. This camera hardware has been used for passive monitoring of the plasma in different devices for example at ASDEX Upgrade and COMPASS with the first version of its firmware. The new firmware and software package is now available and ready for testing the new event processing features. This paper will present the operation principle and features of the Event Detection Intelligent Camera (EDICAM). The device is intended to be the central element in the 10-camera monitoring system of the Wendelstein 7-X stellarator.

  6. High Efficiency mm-Wave Transmitter Array

    Science.gov (United States)

    2016-09-01

    Research Triangle Park, NC 27709-2211 Mm-waves. power amplifiers, Si integrated circuits, antenna arrays REPORT DOCUMENTATION PAGE 11. SPONSOR...Array Report Title High efficiency, high power transmitters integrated in silicon at 45, 94 and 138 GHz were developed. Our approach employs CMOS-SOI...based power amplifiers had a variety of advantages over nMOS PAs. Advancements have been reported in detail in numerous publications (13 journal

  7. Streak cameras and their applications

    International Nuclear Information System (INIS)

    Bernet, J.M.; Imhoff, C.

    1987-01-01

    Over the last several years, development of various measurement techniques in the nanosecond and pico-second range has led to increased reliance on streak cameras. This paper will present the main electronic and optoelectronic performances of the Thomson-CSF TSN 506 cameras and their associated devices used to build an automatic image acquisition and processing system (NORMA). A brief survey of the diversity and the spread of the use of high speed electronic cinematography will be illustrated by a few typical applications [fr

  8. X-ray analytics for 450-mm wafer; Roentgenanalytik fuer 450-mm-Wafer

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2014-09-15

    The introduction of the 450-mm technology in the wafer fabrication and the further reduction of critical dimensions requires improved X-ray analysis methods. Therefor the PTB has concipated a metrology chamber for the characterization of 450-mm wafers, the crucial element of which is a multi-axis patent-pending manipulator.

  9. Frontal soft tissue analysis using a 3 dimensional camera following two-jaw rotational orthognathic surgery in skeletal class III patients.

    Science.gov (United States)

    Choi, Jong Woo; Lee, Jang Yeol; Oh, Tae-Suk; Kwon, Soon Man; Yang, Sung Joon; Koh, Kyung Suk

    2014-04-01

    Although two dimensional cephalometry is the standard method for analyzing the results of orthognathic surgery, it has potential limits in frontal soft tissue analysis. We have utilized a 3 dimensional camera to examine changes in soft tissue landmarks in patients with skeletal class III dentofacial deformity who underwent two-jaw rotational setback surgery. We assessed 25 consecutive Asian patients (mean age, 22 years; range, 17-32 years) with skeletal class III dentofacial deformities who underwent two-jaw rotational surgery without maxillary advancement. Using a 3D camera, we analyzed changes in facial proportions, including vertical and horizontal dimensions, facial surface areas, nose profile, lip contour, and soft tissue cheek convexity, as well as landmarks related to facial symmetry. The average mandibular setback was 10.7 mm (range: 5-17 mm). The average SNA changed from 77.4° to 77.8°, the average SNB from 89.2° to 81.1°, and the average occlusal plane from 8.7° to 11.4°. The mid third vertical dimension changed from 58.8 mm to 57.8 mm (p = 0.059), and the lower third vertical dimension changed from 70.4 mm to 68.2 mm (p = 0.0006). The average bigonial width decreased from 113.5 mm to 109.2 mm (p = 0.0028), the alar width increased from 34.7 mm to 36.1 mm (p-value = 0.0002), and lip length was unchanged. Mean mid and lower facial surface areas decreased significantly, from 171.8 cm(2) to 166.2 cm(2) (p = 0.026) and from 71.23 cm(2) to 61.9 cm(2) (p analysis for orthognathic surgery, and enabled quantitative analysis of changes in frontal soft tissue landmarks and facial proportions that were not possible with conventional 2D cephalometric analysis. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  10. The Camera Comes to Court.

    Science.gov (United States)

    Floren, Leola

    After the Lindbergh kidnapping trial in 1935, the American Bar Association sought to eliminate electronic equipment from courtroom proceedings. Eventually, all but two states adopted regulations applying that ban to some extent, and a 1965 Supreme Court decision encouraged the banning of television cameras at trials as well. Currently, some states…

  11. High-speed holographic camera

    International Nuclear Information System (INIS)

    Novaro, Marc

    The high-speed holographic camera is a disgnostic instrument using holography as an information storing support. It allows us to take 10 holograms, of an object, with exposures times of 1,5ns, separated in time by 1 or 2ns. In order to get these results easily, no mobile part is used in the set-up [fr

  12. Camera Movement in Narrative Cinema

    DEFF Research Database (Denmark)

    Nielsen, Jakob Isak

    2007-01-01

    Just like art historians have focused on e.g. composition or lighting, this dissertation takes a single stylistic parameter as its object of study: camera movement. Within film studies this localized avenue of middle-level research has become increasingly viable under the aegis of a perspective k...

  13. The LSST camera system overview

    Science.gov (United States)

    Gilmore, Kirk; Kahn, Steven; Nordby, Martin; Burke, David; O'Connor, Paul; Oliver, John; Radeka, Veljko; Schalk, Terry; Schindler, Rafe

    2006-06-01

    The LSST camera is a wide-field optical (0.35-1um) imager designed to provide a 3.5 degree FOV with better than 0.2 arcsecond sampling. The detector format will be a circular mosaic providing approximately 3.2 Gigapixels per image. The camera includes a filter mechanism and, shuttering capability. It is positioned in the middle of the telescope where cross-sectional area is constrained by optical vignetting and heat dissipation must be controlled to limit thermal gradients in the optical beam. The fast, f/1.2 beam will require tight tolerances on the focal plane mechanical assembly. The focal plane array operates at a temperature of approximately -100°C to achieve desired detector performance. The focal plane array is contained within an evacuated cryostat, which incorporates detector front-end electronics and thermal control. The cryostat lens serves as an entrance window and vacuum seal for the cryostat. Similarly, the camera body lens serves as an entrance window and gas seal for the camera housing, which is filled with a suitable gas to provide the operating environment for the shutter and filter change mechanisms. The filter carousel can accommodate 5 filters, each 75 cm in diameter, for rapid exchange without external intervention.

  14. Toy Cameras and Color Photographs.

    Science.gov (United States)

    Speight, Jerry

    1979-01-01

    The technique of using toy cameras for both black-and-white and color photography in the art class is described. The author suggests that expensive equipment can limit the growth of a beginning photographer by emphasizing technique and equipment instead of in-depth experience with composition fundamentals and ideas. (KC)

  15. Gamma camera with reflectivity mask

    International Nuclear Information System (INIS)

    Stout, K.J.

    1980-01-01

    In accordance with the present invention there is provided a radiographic camera comprising: a scintillator; a plurality of photodectors positioned to face said scintillator; a plurality of masked regions formed upon a face of said scintillator opposite said photdetectors and positioned coaxially with respective ones of said photodetectors for decreasing the amount of internal reflection of optical photons generated within said scintillator. (auth)

  16. A study of full width at half maximum (FWHM) according to the filter's cut off level in SPECT camera

    International Nuclear Information System (INIS)

    Park, Soung Ock; Kwon, Soo Il

    2003-01-01

    Filtering is necessary to reduce statistical noise and to increase image quality in SPECT images. Noises controlled by low-pass filter designed to suppress high spatial frequency in SPECT image. Most SPECT filter function control the degree of high frequency suppression by choosing a cut off frequency. The location of cut off frequency determines the affect image noise and spatial resolution. If select the low cut off frequency, its provide good noise suppression but insufficient image quantity and high cut off frequencies increase the image resolution but insufficient noise suppression. The purpose of this study was to determines the optimum cut off level with comparison of FWHM according to cut off level in each filters-Band-limited, Sheep-logan, Sheep-logan Hanning, Generalized Hamming, Low pass cosine, Parazen and Butterworth filter in SPECT camera. We recorded image along the X, Y, Z-axis with 99m TcO 4 point source and measured FWHM by use profile curve. We find averaged length is 9.16 mm ∼ 18.14 mm of FWHM in X, Y, and Z-axis, and Band-limited and Generalized Hamming filters measures 9.16 mm at 0.7 cycle/pixel cut off frequency

  17. Observation of the dynamic movement of fragmentations by high-speed camera and high-speed video

    Science.gov (United States)

    Suk, Chul-Gi; Ogata, Yuji; Wada, Yuji; Katsuyama, Kunihisa

    1995-05-01

    The experiments of blastings using mortal concrete blocks and model concrete columns were carried out in order to obtain technical information on fragmentation caused by the blasting demolition. The dimensions of mortal concrete blocks were 1,000 X 1,000 X 1,000 mm. Six kinds of experimental blastings were carried out using mortal concrete blocks. In these experiments precision detonators and No. 6 electric detonators with 10 cm detonating fuse were used and discussed the control of fragmentation. As the results of experiment it was clear that the flying distance of fragmentation can be controlled using a precise blasting system. The reinforced concrete model columns for typical apartment houses in Japan were applied to the experiments. The dimension of concrete test column was 800 X 800 X 2400 mm and buried 400 mm in the ground. The specified design strength of the concrete was 210 kgf/cm2. These columns were exploded by the blasting with internal loading of dynamite. The fragmentation were observed by two kinds of high speed camera with 500 and 2000 FPS and a high speed video with 400 FPS. As one of the results in the experiments, the velocity of fragmentation, blasted 330 g of explosive with the minimum resisting length of 0.32 m, was measured as much as about 40 m/s.

  18. MM&T for VHSIC Multichip Packages

    Science.gov (United States)

    1989-09-20

    a socket of this type and Nepenthe /Yamaichi by far out- distanced the other two in virtually every area. The Nepenthe socket is a high- quality...successfully on another program. Drawings of the 308 lead socket and carrier were purchased from Nepenthe and drawings of them can be found in Appendix B...SCALE NONE SHEET 5. 8-24 a,•.. . ,.,...,,.a ,. ~ m mmlm mllmm mm m m • • m I SUGGESTED SOURCE(S) OF SUPPLY: I. NEPENTHE (No FSCM No.) 2471 East

  19. Rotman lens for mm-wavelengths

    Science.gov (United States)

    Hall, Leonard T.; Hansen, Hedley J.; Abbott, Derek

    2002-11-01

    The 77 GHz band has been reserved for intelligent cruise control in luxury cars and some public transport services in America and the United Kingdom. The Rotman lens offers a cheap and compact means to extend the single beam systems generally used, to fully functional beam staring arrangements. Rotman lenses have been built for microwave frequencies with limited success. The flexibility of microstrip transmission lines and the advent of fast accurate simulation packages allow practical Rotman lenses to be designed at mm-wavelengths. This paper discusses the limitations of the conventional design approach and predicts the performance of a new Rotman lens designed at 77 GHz.

  20. Telomere length analysis.

    Science.gov (United States)

    Canela, Andrés; Klatt, Peter; Blasco, María A

    2007-01-01

    Most somatic cells of long-lived species undergo telomere shortening throughout life. Critically short telomeres trigger loss of cell viability in tissues, which has been related to alteration of tissue function and loss of regenerative capabilities in aging and aging-related diseases. Hence, telomere length is an important biomarker for aging and can be used in the prognosis of aging diseases. These facts highlight the importance of developing methods for telomere length determination that can be employed to evaluate telomere length during the human aging process. Telomere length quantification methods have improved greatly in accuracy and sensitivity since the development of the conventional telomeric Southern blot. Here, we describe the different methodologies recently developed for telomere length quantification, as well as their potential applications for human aging studies.

  1. mmView: a web-based viewer of the mmCIF format.

    Science.gov (United States)

    Cech, Petr; Svozil, Daniel

    2011-04-12

    Structural biomolecular data are commonly stored in the PDB format. The PDB format is widely supported by software vendors because of its simplicity and readability. However, the PDB format cannot fully address many informatics challenges related to the growing amount of structural data. To overcome the limitations of the PDB format, a new textual format mmCIF was released in June 1997 in its version 1.0. mmCIF provides extra information which has the advantage of being in a computer readable form. However, this advantage becomes a disadvantage if a human must read and understand the stored data. While software tools exist to help to prepare mmCIF files, the number of available systems simplifying the comprehension and interpretation of the mmCIF files is limited. In this paper we present mmView - a cross-platform web-based application that allows to explore comfortably the structural data of biomacromolecules stored in the mmCIF format. The mmCIF categories can be easily browsed in a tree-like structure, and the corresponding data are presented in a well arranged tabular form. The application also allows to display and investigate biomolecular structures via an integrated Java application Jmol. The mmView software system is primarily intended for educational purposes, but it can also serve as a useful research tool. The mmView application is offered in two flavors: as an open-source stand-alone application (available from http://sourceforge.net/projects/mmview) that can be installed on the user's computer, and as a publicly available web server.

  2. mmView: a web-based viewer of the mmCIF format

    Directory of Open Access Journals (Sweden)

    Svozil Daniel

    2011-04-01

    Full Text Available Abstract Background Structural biomolecular data are commonly stored in the PDB format. The PDB format is widely supported by software vendors because of its simplicity and readability. However, the PDB format cannot fully address many informatics challenges related to the growing amount of structural data. To overcome the limitations of the PDB format, a new textual format mmCIF was released in June 1997 in its version 1.0. mmCIF provides extra information which has the advantage of being in a computer readable form. However, this advantage becomes a disadvantage if a human must read and understand the stored data. While software tools exist to help to prepare mmCIF files, the number of available systems simplifying the comprehension and interpretation of the mmCIF files is limited. Findings In this paper we present mmView - a cross-platform web-based application that allows to explore comfortably the structural data of biomacromolecules stored in the mmCIF format. The mmCIF categories can be easily browsed in a tree-like structure, and the corresponding data are presented in a well arranged tabular form. The application also allows to display and investigate biomolecular structures via an integrated Java application Jmol. Conclusions The mmView software system is primarily intended for educational purposes, but it can also serve as a useful research tool. The mmView application is offered in two flavors: as an open-source stand-alone application (available from http://sourceforge.net/projects/mmview that can be installed on the user's computer, and as a publicly available web server.

  3. An electrically tunable plenoptic camera using a liquid crystal microlens array

    International Nuclear Information System (INIS)

    Lei, Yu; Tong, Qing; Zhang, Xinyu; Sang, Hongshi; Ji, An; Xie, Changsheng

    2015-01-01

    Plenoptic cameras generally employ a microlens array positioned between the main lens and the image sensor to capture the three-dimensional target radiation in the visible range. Because the focal length of common refractive or diffractive microlenses is fixed, the depth of field (DOF) is limited so as to restrict their imaging capability. In this paper, we propose a new plenoptic camera using a liquid crystal microlens array (LCMLA) with electrically tunable focal length. The developed LCMLA is fabricated by traditional photolithography and standard microelectronic techniques, and then, its focusing performance is experimentally presented. The fabricated LCMLA is directly integrated with an image sensor to construct a prototyped LCMLA-based plenoptic camera for acquiring raw radiation of targets. Our experiments demonstrate that the focused region of the LCMLA-based plenoptic camera can be shifted efficiently through electrically tuning the LCMLA used, which is equivalent to the extension of the DOF

  4. An electrically tunable plenoptic camera using a liquid crystal microlens array

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Yu [National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China); Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China); Shijiazhuang Tiedao University, Shijiazhuang 050043 (China); Tong, Qing; Zhang, Xinyu [National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China); Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China); Sang, Hongshi [National Key Laboratory of Science and Technology on Multispectral Information Processing, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Automation, Huazhong University of Science and Technology, Wuhan 430074 (China); Ji, An [Institute of Semiconductors, Chinese Academy of Science, Beijing 100083 (China); Xie, Changsheng [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2015-05-15

    Plenoptic cameras generally employ a microlens array positioned between the main lens and the image sensor to capture the three-dimensional target radiation in the visible range. Because the focal length of common refractive or diffractive microlenses is fixed, the depth of field (DOF) is limited so as to restrict their imaging capability. In this paper, we propose a new plenoptic camera using a liquid crystal microlens array (LCMLA) with electrically tunable focal length. The developed LCMLA is fabricated by traditional photolithography and standard microelectronic techniques, and then, its focusing performance is experimentally presented. The fabricated LCMLA is directly integrated with an image sensor to construct a prototyped LCMLA-based plenoptic camera for acquiring raw radiation of targets. Our experiments demonstrate that the focused region of the LCMLA-based plenoptic camera can be shifted efficiently through electrically tuning the LCMLA used, which is equivalent to the extension of the DOF.

  5. Performance tests of two portable mini gamma cameras for medical applications

    International Nuclear Information System (INIS)

    Sanchez, F.; Fernandez, M. M.; Gimenez, M.; Benlloch, J. M.; Rodriguez-Alvarez, M. J.; Garcia de Quiros, F.; Lerche, Ch. W.; Pavon, N.; Palazon, J. A.; Martinez, J.; Sebastia, A.

    2006-01-01

    We have developed two prototypes of portable gamma cameras for medical applications based on a previous prototype designed and tested by our group. These cameras use a CsI(Na) continuous scintillation crystal coupled to the new flat-panel-type multianode position-sensitive photomultiplier tube, H8500 from Hamamatsu Photonics. One of the prototypes, mainly intended for intrasurgical use, has a field of view of 44x44 mm 2 , and weighs 1.2 kg. Its intrinsic resolution is better than 1.5 mm and its energy resolution is about 13% at 140 keV. The second prototype, mainly intended for osteological, renal, mammary, and endocrine (thyroid, parathyroid, and suprarenal) scintigraphies, weighs a total of 2 kg. Its average spatial resolution is 2 mm; it has a field of view of 95x95 mm 2 , with an energy resolution of about 15% at 140 keV. The main advantages of these gamma camera prototypes with respect to those previously reported in the literature are high portability and low weight, with no significant loss of sensitivity and spatial resolution. All the electronic components are packed inside the mini gamma cameras, and no external electronic devices are required. The cameras are only connected through the universal serial bus port to a portable PC. In this paper, we present the design of the cameras and describe the procedures that have led us to choose their configuration together with the most important performance features of the cameras. For one of the prototypes, clinical tests on melanoma patients are presented and images are compared with those obtained with a conventional camera

  6. Coordinated mm/sub-mm observations of Sagittarius A* in May 2007

    Energy Technology Data Exchange (ETDEWEB)

    Kunneriath, D; Eckart, A; Bertram, T; Konig, S [University of Cologne, Zuelpicher Str. 77, D-50937 Cologne (Germany); Vogel, S [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Sjouwerman, L [National Radio Astronomy Observatory, PO Box 0, Socorro, NM 87801 (United States); Wiesemeyer, H [IRAM, Avenida Divina Pastora, 7, Nuecleo Central, E-18012 Granada (Spain); Schoedel, R [Instituto de AstrofIsica de AndalucIa, Camino Bajo de Huetor 50, 18008 Granada (Spain); Baganoff, F K [Center for Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139-4307 (United States); Morris, M; Mauerhan, J; Meyer, L [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1547 (United States); Dovciak, M; Karas, V [Astronomical Institute, Academy of Sciences, BocnI II, CZ-14131 Prague (Czech Republic); Dowries, D [Institut de Radio Astronomie Millimetrique, Domaine Universitaire, 38406 St. Martin d' Heres (France); Krichbaum, T; Lu, R-S [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, 53121 Bonn (Germany); Krips, M [Harvard-Smithsonian Center for Astrophysics, SMA project, 60 Garden Street, MS 78 Cambridge, MA 02138 (United States); Markoff, S [Astronomical Institute ' Anton Pannekoek' , University of Amsterdam, Kruislaan 403, 1098SJ Amsterdam (Netherlands); Duschl, W J, E-mail: eckart@phl.uni-koeln.de (and others)

    2008-10-15

    At the center of the Milky Way, with a distance of {approx}8 kpc, the compact source Sagittarius A* (SgrA*) can be associated with a super massive black hole of {approx}4x 10{sup 6}M{sub o-dot}. SgrA* shows strong variability from the radio to the X-ray wavelength domains. Here we report on simultaneous NIR/sub-millimeter/X-ray observations from May 2007 that involved the NACO adaptive optics (AO) instrument at the European Southern Observatory's Very Large Telescope, the Australian Telescope Compact Array (ATCA), the US mm-array CARMA, the IRAM 30m mm-telescope, and other telescopes. We concentrate on the time series of mm/sub-mm data from CARMA, ATCA, and the MAMBO bolometer at the IRAM 30m telescope.

  7. Evolving Starburst Modeling of FIR/sub-mm/mm Line Emission. II. Application to M 82

    OpenAIRE

    Yao, Lihong

    2009-01-01

    We present starburst models for far-infrared/sub-millimeter/millimeter (FIR/sub-mm/mm) line emission of molecular and atomic gas in an evolving starburst region, which is treated as an ensemble of non-interacting hot bubbles which drive spherical shells of swept-up gas into a surrounding uniform gas medium. These bubbles and shells are driven by stellar winds and supernovae within massive star clusters formed during an instantaneous starburst. The underlying stellar radiation from the evolvin...

  8. Bunch length and the 102/90 degrees optics

    CERN Document Server

    Lamont, M

    1998-01-01

    The bunch length in LEP has become a cause for concern, particularly in the ramp to high energies. Short bunch lengths excite higher order modes which can cause heating of the inter-cavity bellows a nd may be picked up by antennae cables causing burning. The bunch length is also important from a cryogenics viewpoint; HOM losses go up with shorter bunches and more cryogenics power is required. Measurements made during 1997 show that it is strongly advisable to maintain bunch lengths above 9 mm particularly with high bunch currents. The use of a low emittance lattice such as 102/90 degr ees exacerbates the problem; because of the decreased momentum compaction the bunch lengths are naturally shorter. This paper quantifies the bunch lengths to be expected at various stages of ope ration in 1998 and presents recommendations for the avoidance of bunch lengths shorter than 9 mm.

  9. The Same-Source Parallel MM5

    Directory of Open Access Journals (Sweden)

    John Michalakes

    2000-01-01

    Full Text Available Beginning with the March 1998 release of the Penn State University/NCAR Mesoscale Model (MM5, and continuing through eight subsequent releases up to the present, the official version has run on distributed -memory (DM parallel computers. Source translation and runtime library support minimize the impact of parallelization on the original model source code, with the result that the majority of code is line-for-line identical with the original version. Parallel performance and scaling are equivalent to earlier, hand-parallelized versions; the modifications have no effect when the code is compiled and run without the DM option. Supported computers include the IBM SP, Cray T3E, Fujitsu VPP, Compaq Alpha clusters, and clusters of PCs (so-called Beowulf clusters. The approach also is compatible with shared-memory parallel directives, allowing distributed-memory/shared-memory hybrid parallelization on distributed-memory clusters of symmetric multiprocessors.

  10. Transportation studies: 40-MM collider dipole magnets

    International Nuclear Information System (INIS)

    Daly, E.

    1992-01-01

    Several fully functional 40-mm Collider Dipole Magnets (CDM) were instrumented with accelerometers to monitor shock and vibration loads during transport. The magnets were measured with optical tooling telescopes before and after transport. Changes in mechanical alignment due to shipping and handling were determined. The mechanical stability of the cryogen lines were checked using the same method. Field quality and dipole angle were measured warm before and after transport to determine changes in these parameters. Power spectra were calculated for accelerometers located on the cold mass, vacuum vessel, and trailer bed. Where available, plots of field quality and dipole roll both before and after were created. Shipping loads measured were largest in the vertical direction, where most of the structural deformation of the magnet was evident. It was not clear that magnetic performance was affected by the shipping and handling environment

  11. On the study of ricochet and penetration in sand, water and gelatin by spheres, 7.62 mm APM2, and 25 mm projectiles

    Directory of Open Access Journals (Sweden)

    John F. Moxnes

    2016-04-01

    Full Text Available We examine the ricochet and penetration behavior in sand, water and gelatin by steel spheres, 7.62 mm APM2 and 25 mm projectiles. A threshold impact angle (critical angle exists beyond which ricochet cannot occur. The Autodyn simulation code with the smooth particle hydrodynamic (SPH method and Impetus Afea Solver with the corpuscular model are used and the results are compared with experimental and analytical results. The resistance force in sand for spheres was proportional to a term quadratic in velocity plus a term linear in velocity. The drag coefficient for the quadratic term was 0.65. The Autodyn and Impetus Afea codes simulate too large penetration due to the lack of a linear velocity resistance force. Critical ricochet angles were consistent with analytical results in the literature. In ballistic gelatin at velocities of 50–850 m/s a drag coefficient of 0.30 fits the high speed camera recordings if a linear velocity resistance term is included. However, only a quadratic velocity resistance force with drag coefficient that varies with the Reynolds number also fits the measurements. The simulation of a sphere in water with Autodyn showed too large drag coefficient. The 7.62 mm APM2 core simulations in sand fit reasonable well for both codes. The 25 mm projectile ricochet simulations in sand show consistency with the high speed camera recordings. Computer time was reduced by one to two orders of magnitudes when applying the Impetus Afea Solver compared to Autodyn code due to the use of the graphics processing units (GPU.

  12. Effect of realistic vehicle seats, cushion length, and lap belt geometry on child ATD kinematics.

    Science.gov (United States)

    2011-12-01

    This series of sled tests examined the effect of using real vehicle seats on child ATD performance. Cushion length was varied from production length of 450 mm to a shorter length of 350 mm. Lap belt geometry was set to rear, mid, and forward anchorag...

  13. Architectural Design Document for Camera Models

    DEFF Research Database (Denmark)

    Thuesen, Gøsta

    1998-01-01

    Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study.......Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study....

  14. Commissioning of the advanced light source dual-axis streak camera

    International Nuclear Information System (INIS)

    Hinkson, J.; Keller, R.; Byrd, J.

    1997-05-01

    A dual-axis camera, Hamamatsu model C5680, has been installed on the Advanced Light Source photon-diagnostics beam-line to investigate electron-beam parameters. During its commissioning process, the camera has been used to measure single-bunch length vs. current, relative bunch charge in adjacent RF buckets, and bunchphase stability. In this paper the authors describe the visible-light branch of the diagnostics beam-line, the streak-camera installation, and the timing electronics. They will show graphical results of beam measurements taken during a variety of accelerator conditions

  15. Telomere length and depression

    DEFF Research Database (Denmark)

    Wium-Andersen, Marie Kim; Ørsted, David Dynnes; Rode, Line

    2017-01-01

    BACKGROUND: Depression has been cross-sectionally associated with short telomeres as a measure of biological age. However, the direction and nature of the association is currently unclear. AIMS: We examined whether short telomere length is associated with depression cross-sectionally as well...... as prospectively and genetically. METHOD: Telomere length and three polymorphisms, TERT, TERC and OBFC1, were measured in 67 306 individuals aged 20-100 years from the Danish general population and associated with register-based attendance at hospital for depression and purchase of antidepressant medication....... RESULTS: Attendance at hospital for depression was associated with short telomere length cross-sectionally, but not prospectively. Further, purchase of antidepressant medication was not associated with short telomere length cross-sectionally or prospectively. Mean follow-up was 7.6 years (range 0...

  16. Myofilament length dependent activation

    Energy Technology Data Exchange (ETDEWEB)

    de Tombe, Pieter P.; Mateja, Ryan D.; Tachampa, Kittipong; Mou, Younss Ait; Farman, Gerrie P.; Irving, Thomas C. (IIT); (Loyola)

    2010-05-25

    The Frank-Starling law of the heart describes the interrelationship between end-diastolic volume and cardiac ejection volume, a regulatory system that operates on a beat-to-beat basis. The main cellular mechanism that underlies this phenomenon is an increase in the responsiveness of cardiac myofilaments to activating Ca{sup 2+} ions at a longer sarcomere length, commonly referred to as myofilament length-dependent activation. This review focuses on what molecular mechanisms may underlie myofilament length dependency. Specifically, the roles of inter-filament spacing, thick and thin filament based regulation, as well as sarcomeric regulatory proteins are discussed. Although the 'Frank-Starling law of the heart' constitutes a fundamental cardiac property that has been appreciated for well over a century, it is still not known in muscle how the contractile apparatus transduces the information concerning sarcomere length to modulate ventricular pressure development.

  17. The Use of Camera Traps in Wildlife

    OpenAIRE

    Yasin Uçarlı; Bülent Sağlam

    2013-01-01

    Camera traps are increasingly used in the abundance and density estimates of wildlife species. Camera traps are very good alternative for direct observation in case, particularly, steep terrain, dense vegetation covered areas or nocturnal species. The main reason for the use of camera traps is eliminated that the economic, personnel and time loss in a continuous manner at the same time in different points. Camera traps, motion and heat sensitive, can take a photo or video according to the mod...

  18. Stereo Pinhole Camera: Assembly and experimental activities

    OpenAIRE

    Santos, Gilmário Barbosa; Departamento de Ciência da Computação, Universidade do Estado de Santa Catarina, Joinville; Cunha, Sidney Pinto; Centro de Tecnologia da Informação Renato Archer, Campinas

    2015-01-01

    This work describes the assembling of a stereo pinhole camera for capturing stereo-pairs of images and proposes experimental activities with it. A pinhole camera can be as sophisticated as you want, or so simple that it could be handcrafted with practically recyclable materials. This paper describes the practical use of the pinhole camera throughout history and currently. Aspects of optics and geometry involved in the building of the stereo pinhole camera are presented with illustrations. Fur...

  19. Upper Extremity Length Equalization

    OpenAIRE

    DeCoster, Thomas A.; Ritterbusch, John; Crawford, Mark

    1992-01-01

    Significant upper extremity length inequality is uncommon but can cause major functional problems. The ability to position and use the hand may be impaired by shortness of any of the long bones of the upper extremity. In many respects upper and lower extremity length problems are similar. They most commonly occur after injury to a growing bone and the treatment modalities utilized in the lower extremity may be applied to the upper extremity. These treatment options include epiphysiodesis, sho...

  20. An Open Standard for Camera Trap Data

    NARCIS (Netherlands)

    Forrester, Tavis; O'Brien, Tim; Fegraus, Eric; Jansen, P.A.; Palmer, Jonathan; Kays, Roland; Ahumada, Jorge; Stern, Beth; McShea, William

    2016-01-01

    Camera traps that capture photos of animals are a valuable tool for monitoring biodiversity. The use of camera traps is rapidly increasing and there is an urgent need for standardization to facilitate data management, reporting and data sharing. Here we offer the Camera Trap Metadata Standard as an

  1. A camera specification for tendering purposes

    International Nuclear Information System (INIS)

    Lunt, M.J.; Davies, M.D.; Kenyon, N.G.

    1985-01-01

    A standardized document is described which is suitable for sending to companies which are being invited to tender for the supply of a gamma camera. The document refers to various features of the camera, the performance specification of the camera, maintenance details, price quotations for various options and delivery, installation and warranty details. (U.K.)

  2. Compact large FoV gamma camera for breast molecular imaging

    Science.gov (United States)

    Pani, R.; Cinti, M. N.; Pellegrini, R.; Betti, M.; Devincentis, G.; Bennati, P.; Ridolfi, S.; Iurlaro, G.; Montani, L.; Scafè, R.; Marini, M.; Porfiri, L. M.; Giachetti, G.; Baglini, F.; Salvadori, G.; Madesani, M.; Pieracci, M.; Catarsi, F.; Bigongiari, A.

    2006-12-01

    The very low sensitivity of scintimammography for tumours under 1 cm in diameter, with current nuclear medicine cameras, is the major limitation in recommending this test modality for screening purposes. To improve this diagnostic technique,a new concept of scintillation gamma camera, which fits the best requirements for functional breast imaging has been developed under "Integrated Mammographic Imaging" (IMI) project. This camera consists of a large detection head (6″×7″),very compact sized and with light weight to be easily positioned in the same X-ray geometry. The detection head consists of matrix of 42 photodetector Hamamatsu 1 in 2 square H8520-C12 PSPMTs, which are closely packed and coupled to a NaI(Tl) scintillating array, with individual crystal pixel 2×2×6 mm 3 size. Large FoV camera shows a very good pixel identification in the detection dead zones between tubes allowing an accurate LUT correction of the final image reconstruction. Electronic read-out was especially designed to optimize the intrinsic spatial resolution and camera compactness. With respect to Anger camera, the overall spatial resolution is improved up to 40% while the overall energy resolution values is ˜16% at 140 keV. Large FoV dedicated camera was characterized and tested by phantom studies; and clinical trials are currently performed. For all patients, compression views have been acquiring for both breasts in craniocaudal projections, and are compared with standard gamma camera images.

  3. Relative camera localisation in non-overlapping camera networks using multiple trajectories

    NARCIS (Netherlands)

    John, V.; Englebienne, G.; Kröse, B.J.A.

    2012-01-01

    In this article we present an automatic camera calibration algorithm using multiple trajectories in a multiple camera network with non-overlapping field-of-views (FOV). Visible trajectories within a camera FOV are assumed to be measured with respect to the camera local co-ordinate system.

  4. Ultrasound Assessment of Cervical Length in Pregnancy

    Directory of Open Access Journals (Sweden)

    An-Shine Chao

    2008-09-01

    Full Text Available Cervical length in high-risk women for preterm birth has to be identified before early second trimester. Sequential evaluations lead to high predictive significance. The mean cervical length at 24 weeks is about 35 mm when measured by transvaginal ultrasound. A short cervix is defined as a cervix that is less than 25 mm and funneling, i.e. ballooning of the membranes into a dilated internal os, but with a closed external os. Factors such as short cervical length, uterine anomaly, previous cervical surgery, multiple gestation and positive fetal fibronectin results are associated with preterm delivery. Serial transvaginal ultrasound examinations during the early second trimester would provide longitudinal changes in the cervical length. The use of 17α-hydroxyprogesterone caproate and cerclage has shown to be beneficial in preventing preterm delivery. When combined with other predictors such as occiput position, parity, maternal age and body mass index, cervical length is a useful parameter for predicting the feasibility of labor induction and successful delivery.

  5. Design studies of a depth encoding large aperture PET camera

    International Nuclear Information System (INIS)

    Moisan, C.; Rogers, J.G.; Buckley, K.R.; Ruth, T.J.; Stazyk, M.W.; Tsang, G.

    1994-10-01

    The feasibility of a wholebody PET tomograph with the capacity to correct for the parallax error induced by the Depth-Of-Interaction of γ-rays is assessed through simulation. The experimental energy, depth, and transverse position resolutions of BGO block detector candidates are the main inputs to a simulation that predicts the point source resolution of the Depth Encoding Large Aperture Camera (DELAC). The results indicate that a measured depth resolution of 7 mm (FWHM) is sufficient to correct a substantial part of the parallax error for a point source at the edge of the Field-Of-View. A search for the block specifications and camera ring radius that would optimize the spatial resolution and its uniformity across the Field-Of-View is also presented. (author). 10 refs., 1 tab., 5 figs

  6. Modelling Virtual Camera Behaviour Through Player Gaze

    DEFF Research Database (Denmark)

    Picardi, Andrea; Burelli, Paolo; Yannakakis, Georgios N.

    2012-01-01

    In a three-dimensional virtual environment, aspects such as narrative and interaction largely depend on the placement and animation of the virtual camera. Therefore, virtual camera control plays a critical role in player experience and, thereby, in the overall quality of a computer game. Both game...... on the relationship between virtual camera, game-play and player behaviour. We run a game user experiment to shed some light on this relationship and identify relevant dif- ferences between camera behaviours through different game sessions, playing behaviours and player gaze patterns. Re- sults show that users can...... be efficiently profiled in dissimilar clusters according to camera control as part of their game- play behaviour....

  7. Stereo Pinhole Camera: Assembly and experimental activities

    Directory of Open Access Journals (Sweden)

    Gilmário Barbosa Santos

    2015-05-01

    Full Text Available This work describes the assembling of a stereo pinhole camera for capturing stereo-pairs of images and proposes experimental activities with it. A pinhole camera can be as sophisticated as you want, or so simple that it could be handcrafted with practically recyclable materials. This paper describes the practical use of the pinhole camera throughout history and currently. Aspects of optics and geometry involved in the building of the stereo pinhole camera are presented with illustrations. Furthermore, experiments are proposed by using the images obtained by the camera for 3D visualization through a pair of anaglyph glasses, and the estimation of relative depth by triangulation is discussed.

  8. Adapting virtual camera behaviour through player modelling

    DEFF Research Database (Denmark)

    Burelli, Paolo; Yannakakis, Georgios N.

    2015-01-01

    Research in virtual camera control has focused primarily on finding methods to allow designers to place cameras effectively and efficiently in dynamic and unpredictable environments, and to generate complex and dynamic plans for cinematography in virtual environments. In this article, we propose...... a novel approach to virtual camera control, which builds upon camera control and player modelling to provide the user with an adaptive point-of-view. To achieve this goal, we propose a methodology to model the player’s preferences on virtual camera movements and we employ the resulting models to tailor...

  9. Development of a high resolution gamma camera system using finely grooved GAGG scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Kataoka, Jun; Oshima, Tsubasa [Research Institute for Science and Engineering, Waseda University (Japan); Ogata, Yoshimune [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu; Hatazawa, Jun [Osaka University Graduate School of Medicine (Japan)

    2016-06-11

    High resolution gamma cameras require small pixel scintillator blocks with high light output. However, manufacturing a small pixel scintillator block is difficult when the pixel size becomes small. To solve this limitation, we developed a high resolution gamma camera system using a finely grooved Ce-doped Gd{sub 3}Al{sub 2}Ga{sub 3}O{sub 12} (GAGG) plate. Our gamma camera's detector consists of a 1-mm-thick finely grooved GAGG plate that is optically coupled to a 1-in. position sensitive photomultiplier tube (PSPMT). The grooved GAGG plate has 0.2×0.2 mm pixels with 0.05-mm wide slits (between the pixels) that were manufactured using a dicing saw. We used a Hamamatsu PSPMT with a 1-in. square high quantum efficiency (HQE) PSPMT (R8900-100-C12). The energy resolution for the Co-57 gamma photons (122 keV) was 18.5% FWHM. The intrinsic spatial resolution was estimated to be 0.7-mm FWHM. With a 0.5-mm diameter pinhole collimator mounted to its front, we achieved a high resolution, small field-of-view gamma camera. The system spatial resolution for the Co-57 gamma photons was 1.0-mm FWHM, and the sensitivity was 0.0025%, 10 mm from the collimator surface. The Tc-99m HMDP administered mouse images showed the fine structures of the mouse body's parts. Our developed high resolution small pixel GAGG gamma camera is promising for such small animal imaging.

  10. Quench performance of 50-mm aperture, 15-m-long SSC dipole magnets built at Fermilab

    International Nuclear Information System (INIS)

    Kuzminski, J.; Bush, T.; Coombes, R.

    1992-07-01

    The quench performance, ramp rate dependence, and mechanical behavior of ten full-length, 50-mm-aperture, SSC dipole magnets built at Fermilab are discussed. Cold testing of these magnets shows that the quench plateau established at 4.35 K exceeds the design value by more than 10%, virtually without training

  11. 16mm Film and Videotape Lectures and Demonstrations. 1976/1977 Catalog.

    Science.gov (United States)

    Massachusetts Inst. of Tech., Cambridge. Center for Advanced Engineering Study.

    The Massachusetts Institute of Technology provides a catalog of 16mm filmed and videotaped lectures and demonstrations. Each listing includes title, short description, length of presentation, catalog number, purchase and rental prices, and indications as to whether the item is film or videotape and black-and-white or color. The catalog is divided…

  12. Initial laboratory evaluation of color video cameras

    Energy Technology Data Exchange (ETDEWEB)

    Terry, P L

    1991-01-01

    Sandia National Laboratories has considerable experience with monochrome video cameras used in alarm assessment video systems. Most of these systems, used for perimeter protection, were designed to classify rather than identify an intruder. Monochrome cameras are adequate for that application and were selected over color cameras because of their greater sensitivity and resolution. There is a growing interest in the identification function of security video systems for both access control and insider protection. Color information is useful for identification purposes, and color camera technology is rapidly changing. Thus, Sandia National Laboratories established an ongoing program to evaluate color solid-state cameras. Phase one resulted in the publishing of a report titled, Initial Laboratory Evaluation of Color Video Cameras (SAND--91-2579).'' It gave a brief discussion of imager chips and color cameras and monitors, described the camera selection, detailed traditional test parameters and procedures, and gave the results of the evaluation of twelve cameras. In phase two six additional cameras were tested by the traditional methods and all eighteen cameras were tested by newly developed methods. This report details both the traditional and newly developed test parameters and procedures, and gives the results of both evaluations.

  13. Relativistic Length Agony Continued

    Science.gov (United States)

    Redzic, D. V.

    2014-06-01

    We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redzic 2008b), we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the 'pole in a barn' paradox.

  14. Telomere Length and Mortality

    DEFF Research Database (Denmark)

    Kimura, Masayuki; Hjelmborg, Jacob V B; Gardner, Jeffrey P

    2008-01-01

    Leukocyte telomere length, representing the mean length of all telomeres in leukocytes, is ostensibly a bioindicator of human aging. The authors hypothesized that shorter telomeres might forecast imminent mortality in elderly people better than leukocyte telomere length. They performed mortality...... telomeres predicted the death of the first co-twin better than the mTRFL did (mTRFL: 0.56, 95% confidence interval (CI): 0.49, 0.63; mTRFL(50): 0.59, 95% CI: 0.52, 0.66; mTRFL(25): 0.59, 95% CI: 0.52, 0.66; MTRFL: 0.60, 95% CI: 0.53, 0.67). The telomere-mortality association was stronger in years 3-4 than...

  15. Failure load of patellar tendon grafts at the femoral side: 10- versus 20-mm-bone blocks

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); M.J.N. Niggebrugge (Marnix); J.A.N. Verhaar (Jan)

    2009-01-01

    textabstractThe aim of the study was to investigate whether use of short bone blocks is safe in anterior cruciate ligament (ACL) reconstruction. Our hypothesis was that the smaller 10-mm-length bone blocks will fail at lower loads than 20-mm-bone blocks. Ten paired human cadaver knees were randomly

  16. Demonstration of the CDMA-mode CAOS smart camera.

    Science.gov (United States)

    Riza, Nabeel A; Mazhar, Mohsin A

    2017-12-11

    Demonstrated is the code division multiple access (CDMA)-mode coded access optical sensor (CAOS) smart camera suited for bright target scenarios. Deploying a silicon CMOS sensor and a silicon point detector within a digital micro-mirror device (DMD)-based spatially isolating hybrid camera design, this smart imager first engages the DMD starring mode with a controlled factor of 200 high optical attenuation of the scene irradiance to provide a classic unsaturated CMOS sensor-based image for target intelligence gathering. Next, this CMOS sensor provided image data is used to acquire a focused zone more robust un-attenuated true target image using the time-modulated CDMA-mode of the CAOS camera. Using four different bright light test target scenes, successfully demonstrated is a proof-of-concept visible band CAOS smart camera operating in the CDMA-mode using up-to 4096 bits length Walsh design CAOS pixel codes with a maximum 10 KHz code bit rate giving a 0.4096 seconds CAOS frame acquisition time. A 16-bit analog-to-digital converter (ADC) with time domain correlation digital signal processing (DSP) generates the CDMA-mode images with a 3600 CAOS pixel count and a best spatial resolution of one micro-mirror square pixel size of 13.68 μm side. The CDMA-mode of the CAOS smart camera is suited for applications where robust high dynamic range (DR) imaging is needed for un-attenuated un-spoiled bright light spectrally diverse targets.

  17. Off-axis scatter measurement of the Mars reconnaissance Orbiter (MRO) Optical Navigation Camera (ONC)

    Science.gov (United States)

    Stauder, John L.; Lowman, Andrew E.; Thiessen, Dave; Day, Darryl; Miles, D. O.

    2005-08-01

    The Optical Navigation Camera (ONC) is part of NASA's Mars Reconnaissance Orbiter (MRO) scheduled for an August 2005 launch. The design is a 500 mm focal length, F/8.3 Ritchey-Chretien with a refractive field corrector. Prior to flight, the off-axis performance of the ONC was measured at visible wavelengths in the off-axis scatter facility at the Space Dynamics Laboratory (SDL). This unique facility is designed to minimize scatter from the test setup to prevent data corruption. Testing was conducted in a clean room environment, and the results indicate that no detectable contamination of the optics occurred during testing. Measurements were taken in two time frames to correct an unanticipated stray light path, which occurred just outside of the sensor's field-of-view. The source of the offending path was identified as scatter from the edges of the field corrector lenses. Specifically, scatter from the interface between the flat ground glass and polished surfaces resulted in significant "humps" in the off-axis response centered at +/- 1.5°. Retesting showed the removal of the humps, and an overall satisfactory performance of the ONC. The troubleshooting, correction, and lessons learned regarding the above stray light path was reported on in an earlier paper. This paper discusses the measurement process, results, and a comparison to a software prediction and other planetary sensors. The measurement validated the final stray light design and complemented the software analysis.

  18. Measuring the orbit length of the Tevatron

    International Nuclear Information System (INIS)

    Kerns, C.; Kerns, Q.; Miller, H.

    1985-06-01

    The orbit length in the Tevatron was measured when coasting beam was first obtained. The method was time-of-flight, using a vernier phase comparison between beam pickup signals and a synthesizer sine wave. Some effort was spent making a stable phase detector so that it would not be a limiting factor. The results exhibited a repeatability of a few Hz at 53 MHz, corresponding to a mean radius measurement to 0.1 mm. 5 refs., 4 figs

  19. Full Length Research Article

    African Journals Online (AJOL)

    Administrator

    Out of the 320 male sheep examined, 87(27.2%) were infected, while 9(19.1%) of the 47 females examined were infected (Table 2). Infection varied from one abattoir to another. Age related distribution of P. cervi is shown in Table 3. Out of 356 adult sheep (>2yrs) examined, 35. Full Length Research Article. 12 ...

  20. Recovery of macroinvertebrates by screening in the field: a comparison between coarse (1.18 mm) and fine (0.60 mm) mesh sieves

    Science.gov (United States)

    Dukerschein, J.T.; Gent, R.; Sauer, J.

    1996-01-01

    We evaluated the potential loss of target benthic macroinvertebrates from coarse-mesh field wash down of samples through a 1.18-mm mesh sieve nested on a 0.60-mm mesh sieve. Visible target organisms (midges, mayflies, and fingernail clams) in the 1.18-mm mesh sieve were removed from the sample and enumerated in the field. The entire contents of both sieves were preserved for subsequent laboratory enumeration under 4X magnification. Percent recoveries from each treatment were based on total intact organisms found in all sieves. Percent recovery for fingernail clams found in the field (31%) was lower than for mayflies (79%) and midges (88%). Laboratory enumeration of organisms retained by the 1.18-mm sieve yielded additional fingernail clams (to total 74% recovered in the field and lab), mayflies (to total 89%), and midges (to total 91%). If the 1.18-mm sieve is used alone in the field, it is adequate to monitor mayflies, midges >1 cm, and adult fingernail clams greater than or equal to 5.0 mm shell length.

  1. High gradient tests of metallic mm-wave accelerating structures

    Science.gov (United States)

    Dal Forno, Massimo; Dolgashev, Valery; Bowden, Gordon; Clarke, Christine; Hogan, Mark; McCormick, Doug; Novokhatski, Alexander; O'Shea, Brendan; Spataro, Bruno; Weathersby, Stephen; Tantawi, Sami G.

    2017-08-01

    This paper explores the physics of vacuum rf breakdowns in high gradient mm-wave accelerating structures. We performed a series of experiments with 100 GHz and 200 GHz metallic accelerating structures, at the Facility for Advanced Accelerator Experimental Tests (FACET) at the SLAC National Accelerator Laboratory. This paper presents the experimental results of rf tests of 100 GHz travelling-wave accelerating structures, made of hard copper-silver alloy. The results are compared with pure hard copper structures. The rf fields were excited by the FACET ultra-relativistic electron beam. The accelerating structures have open geometries, 10 cm long, composed of two halves separated by a variable gap. The rf frequency of the fundamental accelerating mode depends on the gap size and can be changed from 90 GHz to 140 GHz. The measured frequency and pulse length are consistent with our simulations. When the beam travels off-axis, a deflecting field is induced in addition to the decelerating longitudinal field. We measured the deflecting forces by observing the displacement of the electron bunch and used this measurement to verify the expected accelerating gradient. We present the first quantitative measurement of rf breakdown rates in 100 GHz copper-silver accelerating structure, which was 10-3 per pulse, with peak electric field of 0.42 GV/m, an accelerating gradient of 127 MV/m, at a pulse length of 2.3 ns. The goal of our studies is to understand the physics of gradient limitations in order to increase the energy reach of future accelerators.

  2. Periscope-camera system for visible and infrared imaging diagnostics on TFTR

    International Nuclear Information System (INIS)

    Medley, S.S.; Dimock, D.L.; Hayes, S.; Long, D.; Lowrence, J.L.; Mastrocola, V.; Renda, G.; Ulrickson, M.; Young, K.M.

    1985-05-01

    An optical diagnostic consisting of a periscope which relays images of the torus interior to an array of cameras is used on the Tokamak Fusion Test Reactor (TFTR) to view plasma discharge phenomena and inspect vacuum vessel internal structures in both visible and near-infrared wavelength regions. Three periscopes view through 20-cm-diameter fused-silica windows which are spaced around the torus midplane to provide a viewing coverage of approximately 75% of the vacuum vessel internal surface area. The periscopes have f/8 optics and motor-driven controls for focusing, magnification selection (5 0 , 20 0 , and 60 0 field of view), elevation and azimuth setting, mast rotation, filter selection, iris aperture, and viewing port selection. The four viewing ports on each periscope are equipped with multiple imaging devices which include: (1) an inspection eyepiece, (2) standard (RCA TC2900) and fast (RETICON) framing rate television cameras, (3) a PtSi CCD infrared imaging camera, (4) a 35 mm Nikon F3 still camera, or (5) a 16 mm Locam II movie camera with variable framing up to 500 fps. Operation of the periscope-camera system is controlled either locally or remotely through a computer-CAMAC interface. A description of the equipment and examples of its application are presented

  3. Human tracking over camera networks: a review

    Science.gov (United States)

    Hou, Li; Wan, Wanggen; Hwang, Jenq-Neng; Muhammad, Rizwan; Yang, Mingyang; Han, Kang

    2017-12-01

    In recent years, automated human tracking over camera networks is getting essential for video surveillance. The tasks of tracking human over camera networks are not only inherently challenging due to changing human appearance, but also have enormous potentials for a wide range of practical applications, ranging from security surveillance to retail and health care. This review paper surveys the most widely used techniques and recent advances for human tracking over camera networks. Two important functional modules for the human tracking over camera networks are addressed, including human tracking within a camera and human tracking across non-overlapping cameras. The core techniques of human tracking within a camera are discussed based on two aspects, i.e., generative trackers and discriminative trackers. The core techniques of human tracking across non-overlapping cameras are then discussed based on the aspects of human re-identification, camera-link model-based tracking and graph model-based tracking. Our survey aims to address existing problems, challenges, and future research directions based on the analyses of the current progress made toward human tracking techniques over camera networks.

  4. Image compensation for camera and lighting variability

    Science.gov (United States)

    Daley, Wayne D.; Britton, Douglas F.

    1996-12-01

    With the current trend of integrating machine vision systems in industrial manufacturing and inspection applications comes the issue of camera and illumination stabilization. Unless each application is built around a particular camera and highly controlled lighting environment, the interchangeability of cameras of fluctuations in lighting become a problem as each camera usually has a different response. An empirical approach is proposed where color tile data is acquired using the camera of interest, and a mapping is developed to some predetermined reference image using neural networks. A similar analytical approach based on a rough analysis of the imaging systems is also considered for deriving a mapping between cameras. Once a mapping has been determined, all data from one camera is mapped to correspond to the images of the other prior to performing any processing on the data. Instead of writing separate image processing algorithms for the particular image data being received, the image data is adjusted based on each particular camera and lighting situation. All that is required when swapping cameras is the new mapping for the camera being inserted. The image processing algorithms can remain the same as the input data has been adjusted appropriately. The results of utilizing this technique are presented for an inspection application.

  5. Using DSLR cameras in digital holography

    Science.gov (United States)

    Hincapié-Zuluaga, Diego; Herrera-Ramírez, Jorge; García-Sucerquia, Jorge

    2017-08-01

    In Digital Holography (DH), the size of the bidimensional image sensor to record the digital hologram, plays a key role on the performance of this imaging technique; the larger the size of the camera sensor, the better the quality of the final reconstructed image. Scientific cameras with large formats are offered in the market, but their cost and availability limit their use as a first option when implementing DH. Nowadays, DSLR cameras provide an easy-access alternative that is worthwhile to be explored. The DSLR cameras are a wide, commercial, and available option that in comparison with traditional scientific cameras, offer a much lower cost per effective pixel over a large sensing area. However, in the DSLR cameras, with their RGB pixel distribution, the sampling of information is different to the sampling in monochrome cameras usually employed in DH. This fact has implications in their performance. In this work, we discuss why DSLR cameras are not extensively used for DH, taking into account the problem reported by different authors of object replication. Simulations of DH using monochromatic and DSLR cameras are presented and a theoretical deduction for the replication problem using the Fourier theory is also shown. Experimental results of DH implementation using a DSLR camera show the replication problem.

  6. Optimising camera traps for monitoring small mammals.

    Directory of Open Access Journals (Sweden)

    Alistair S Glen

    Full Text Available Practical techniques are required to monitor invasive animals, which are often cryptic and occur at low density. Camera traps have potential for this purpose, but may have problems detecting and identifying small species. A further challenge is how to standardise the size of each camera's field of view so capture rates are comparable between different places and times. We investigated the optimal specifications for a low-cost camera trap for small mammals. The factors tested were 1 trigger speed, 2 passive infrared vs. microwave sensor, 3 white vs. infrared flash, and 4 still photographs vs. video. We also tested a new approach to standardise each camera's field of view. We compared the success rates of four camera trap designs in detecting and taking recognisable photographs of captive stoats (Mustelaerminea, feral cats (Felis catus and hedgehogs (Erinaceuseuropaeus. Trigger speeds of 0.2-2.1 s captured photographs of all three target species unless the animal was running at high speed. The camera with a microwave sensor was prone to false triggers, and often failed to trigger when an animal moved in front of it. A white flash produced photographs that were more readily identified to species than those obtained under infrared light. However, a white flash may be more likely to frighten target animals, potentially affecting detection probabilities. Video footage achieved similar success rates to still cameras but required more processing time and computer memory. Placing two camera traps side by side achieved a higher success rate than using a single camera. Camera traps show considerable promise for monitoring invasive mammal control operations. Further research should address how best to standardise the size of each camera's field of view, maximise the probability that an animal encountering a camera trap will be detected, and eliminate visible or audible cues emitted by camera traps.

  7. Optimising camera traps for monitoring small mammals.

    Science.gov (United States)

    Glen, Alistair S; Cockburn, Stuart; Nichols, Margaret; Ekanayake, Jagath; Warburton, Bruce

    2013-01-01

    Practical techniques are required to monitor invasive animals, which are often cryptic and occur at low density. Camera traps have potential for this purpose, but may have problems detecting and identifying small species. A further challenge is how to standardise the size of each camera's field of view so capture rates are comparable between different places and times. We investigated the optimal specifications for a low-cost camera trap for small mammals. The factors tested were 1) trigger speed, 2) passive infrared vs. microwave sensor, 3) white vs. infrared flash, and 4) still photographs vs. video. We also tested a new approach to standardise each camera's field of view. We compared the success rates of four camera trap designs in detecting and taking recognisable photographs of captive stoats (Mustelaerminea), feral cats (Felis catus) and hedgehogs (Erinaceuseuropaeus). Trigger speeds of 0.2-2.1 s captured photographs of all three target species unless the animal was running at high speed. The camera with a microwave sensor was prone to false triggers, and often failed to trigger when an animal moved in front of it. A white flash produced photographs that were more readily identified to species than those obtained under infrared light. However, a white flash may be more likely to frighten target animals, potentially affecting detection probabilities. Video footage achieved similar success rates to still cameras but required more processing time and computer memory. Placing two camera traps side by side achieved a higher success rate than using a single camera. Camera traps show considerable promise for monitoring invasive mammal control operations. Further research should address how best to standardise the size of each camera's field of view, maximise the probability that an animal encountering a camera trap will be detected, and eliminate visible or audible cues emitted by camera traps.

  8. PWV, Temperature and Wind Statistics at Sites Suitable For mm and Sub-mm Wavelengths Astronomy

    Science.gov (United States)

    Otarola, Angel; Travouillon, Tony; De Breuck, Carlos; Radford, Simon; Matsushita, Satoki; Pérez-Beaupuits, Juan P.

    2018-01-01

    Atmospheric water vapor is the main limiting factor of atmospheric transparency in the mm and sub-mm wavelength spectral windows. Thus, dry sites are needed for the installation and successful operation of radio astronomy observatories exploiting those spectral windows. Other parameters that play an important role in the mechanical response of radio telescopes exposed to the environmental conditions are: temperature, and in particular temperature gradients that induce thermal deformation of mechanical structures, as well as wind magnitude that induce pointing jitter affecting this way the required accuracy in the ability to point to a cosmic source during the observations. Temperature and wind are variables of special consideration when planning the installation and operations of large aperture radio telescopes. This work summarizes the statistics of precipitable water vapor (PWV), temperature and wind monitored at sites by the costal mountain range, as well as on t he west slope of the Andes mountain range in the region of Antofagasta, Chile. This information could prove useful for the planning of the Atacama Large-Aperture Submm/mm Telescope (AtLast).

  9. A 3D HIDAC-PET camera with sub-millimeter resolution for imaging small animals

    International Nuclear Information System (INIS)

    Jeavons, A.P.; Chandler, R.A.; Dettmar, C.A.R.

    1999-01-01

    A HIDAC-PET camera consisting essentially of 5 million 0.5 mm gas avalanching detectors has been constructed for small-animal imaging. The particular HIDAC advantage--a high 3D spatial resolution--has been improved to 0.95 mm fwhm and to 0.7 mm fwhm when reconstructing with 3D-OSEM methods incorporating resolution recovery. A depth-of-interaction resolution of 2.5 mm is implicit, due to the laminar construction. Scatter-corrected sensitivity, at 8.9 cps/kBq (i.e. 0.9%) from a central point source, or 7.2 cps/kBq (543 cps/kBq/cm 3 ) from a distributed (40 mm diameter, 60 mm long) source is now much higher than previous, and other, work. A field-of-view of 100 mm (adjustable to 200 mm) diameter by 210 mm axially permits whole-body imaging of small animals, containing typically 4MBqs of activity, at 40 kcps of which 16% are random coincidences, with a typical scatter fraction of 44%. Throughout the field-of-view there are no positional distortions and relative quantitation is uniform to ± 3.5%, but some variation of spatial resolution is found. The performance demonstrates that HIDAC technology is quite appropriate for small-animal PET cameras

  10. Molecular cloning and analysis of Myc modulator 1 (Mm-1 from Bufo gargarizans (Amphibia: Anura

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2010-02-01

    Full Text Available The protein of Myc modulator 1 (Mm-1 has been reported to repress the transcriptional activity of the proto-oncogene c-Myc in humans. Moreover, it was shown to be the subunit 5 of human prefoldin (PFD. So far, this gene and its homologs have been isolated and sequenced in many organisms, such as mammals and fish, but has not been sequenced for any amphibian or reptile. In order to better understand the function and evolution of Mm-1, we isolated a full-length Mm-1 cDNA (BgMm-1, GenBank accession no. EF211947 from Bufo gargarizans (Cantor, 1842 using RACE (rapid amplification of cDNA ends methods. Mm-1 in B. gargarizans is 755 bp long, comprising an open reading frame (ORF of 459 bp encoding 152 amino acids. The amino acid sequence had a prefoldin α-like domain, partially including a typical putative leucine zipper motif. BgMm-1 showed high similarity to its homolog of Mus musculus Linnaeus, 1758 (82% and Homo sapiens Linnaeus, 1758 MM-1 isoform a (81% at the amino acid level. The protein secondary structure modeled with the SWISS MODEL server revealed that there were two α-helices and four b-strands in BgMm-1 as its human orthologue, and both proteins belonged to the a class of PFD family. The phylogenetic relationships of Mm-1s from lower archaea to high mammals was consistent with the evolution of species, meanwhile the cluster result was consistent with the multiple alignment and the sequence identity analysis. RT-PCR (reverse transcriptase-polymerase chain reaction analysis demonstrated that BgMm-1 expressed widely in ten tissues of adult toad. These results can be helpful for the further investigation on the evolution of Mm-1.

  11. Safety and effectiveness of 5-mm and 10-mm electrothermal bipolar vessel sealers (LigaSure) in laparoscopic resections for sigmoid colon and rectal cancers.

    Science.gov (United States)

    Gezen, Cem; Kement, Metin; Altuntas, Yunus E; Aksakal, Nihat; Okkabaz, Nuri; Civil, Osman; Vural, Selahattin; Oncel, Mustafa

    2012-01-01

    LigaSure™ (Covidien, Mansfield, MA) has been used in cases undergoing laparoscopic colon and rectal resections. This study aims to analyze the efficacy and safety of the 5-mm and 10-mm devices. Patients who received a laparoscopic or hand-assisted laparoscopic operation for a tumor located in the sigmoid colon or rectum since 2006 were abstracted from a prospectively designed database, and findings were analyzed in two groups based on size of the device used during the procedure. The videotapes of the procedures were watched, and operation reports were read to obtain further information on specific intra- and postoperative complications. Demographics, tumor and operation-related information, and postoperative data were compared. Among 215 (128 [59.5%] males; median age, 59.5±13.8 years) patients, data obtained from the 5-mm (n=32) and 10-mm (n=183) groups were identical regarding demographics and data related to tumor (localization and stage) and operation (number of harvested lymph nodes, conversion rates, operation time, intraoperative bleeding, transfusion requirement, reoperation rates, complications, 30-day mortality, and length of hospital stay). However, more patients underwent an anterior resection in the 10-mm group than in the 5-mm group (31.7% versus 15.6%, Pgroup, respectively, P>.05), requiring further attempts for hemorrhage control (n=6), conversion to open surgery (n=1), or relaparotomy (n=1). The 5-mm and 10-mm LigaSure devices are similarly effective and safe during laparoscopic sigmoid colon and rectal resections. Severe bleeding from larger vessels may be observed, requiring conversion to open surgery or relaparotomy.

  12. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  13. Correcting length-frequency distributions for imperfect detection

    Science.gov (United States)

    Breton, André R.; Hawkins, John A.; Winkelman, Dana L.

    2013-01-01

    Sampling gear selects for specific sizes of fish, which may bias length-frequency distributions that are commonly used to assess population size structure, recruitment patterns, growth, and survival. To properly correct for sampling biases caused by gear and other sources, length-frequency distributions need to be corrected for imperfect detection. We describe a method for adjusting length-frequency distributions when capture and recapture probabilities are a function of fish length, temporal variation, and capture history. The method is applied to a study involving the removal of Smallmouth Bass Micropterus dolomieu by boat electrofishing from a 38.6-km reach on the Yampa River, Colorado. Smallmouth Bass longer than 100 mm were marked and released alive from 2005 to 2010 on one or more electrofishing passes and removed on all other passes from the population. Using the Huggins mark–recapture model, we detected a significant effect of fish total length, previous capture history (behavior), year, pass, year×behavior, and year×pass on capture and recapture probabilities. We demonstrate how to partition the Huggins estimate of abundance into length frequencies to correct for these effects. Uncorrected length frequencies of fish removed from Little Yampa Canyon were negatively biased in every year by as much as 88% relative to mark–recapture estimates for the smallest length-class in our analysis (100–110 mm). Bias declined but remained high even for adult length-classes (≥200 mm). The pattern of bias across length-classes was variable across years. The percentage of unadjusted counts that were below the lower 95% confidence interval from our adjusted length-frequency estimates were 95, 89, 84, 78, 81, and 92% from 2005 to 2010, respectively. Length-frequency distributions are widely used in fisheries science and management. Our simple method for correcting length-frequency estimates for imperfect detection could be widely applied when mark–recapture data

  14. The LSST Camera 500 watt -130 degC Mixed Refrigerant Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Bowden, Gordon B.; Langton, Brian J.; /SLAC; Little, William A.; /MMR-Technologies, Mountain View, CA; Powers, Jacob R; Schindler, Rafe H.; /SLAC; Spektor, Sam; /MMR-Technologies, Mountain View, CA

    2014-05-28

    The LSST Camera has a higher cryogenic heat load than previous CCD telescope cameras due to its large size (634 mm diameter focal plane, 3.2 Giga pixels) and its close coupled front-end electronics operating at low temperature inside the cryostat. Various refrigeration technologies are considered for this telescope/camera environment. MMR-Technology’s Mixed Refrigerant technology was chosen. A collaboration with that company was started in 2009. The system, based on a cluster of Joule-Thomson refrigerators running a special blend of mixed refrigerants is described. Both the advantages and problems of applying this technology to telescope camera refrigeration are discussed. Test results from a prototype refrigerator running in a realistic telescope configuration are reported. Current and future stages of the development program are described. (auth)

  15. Development and characterization of a CCD camera system for use on six-inch manipulator systems

    International Nuclear Information System (INIS)

    Logory, L.M.; Bell, P.M.; Conder, A.D.; Lee, F.D.

    1996-01-01

    The Lawrence Livermore National Laboratory has designed, constructed, and fielded a compact CCD camera system for use on the Six Inch Manipulator (SIM) at the Nova laser facility. The camera system has been designed to directly replace the 35 mm film packages on all active SIM-based diagnostics. The unit's electronic package is constructed for small size and high thermal conductivity using proprietary printed circuit board technology, thus reducing the size of the overall camera and improving its performance when operated within the vacuum environment of the Nova laser target chamber. The camera has been calibrated and found to yield a linear response, with superior dynamic range and signal-to-noise levels as compared to T-Max 3200 optic film, while providing real-time access to the data. Limiting factors related to fielding such devices on Nova will be discussed, in addition to planned improvements of the current design

  16. UCXp camera imaging principle and key technologies of data post-processing

    International Nuclear Information System (INIS)

    Yuan, Fangyan; Li, Guoqing; Zuo, Zhengli; Liu, Jianmin; Wu, Liang; Yu, Xiaoping; Zhao, Haitao

    2014-01-01

    The large format digital aerial camera product UCXp was introduced into the Chinese market in 2008, the image consists of 17310 columns and 11310 rows with a pixel size of 6 mm. The UCXp camera has many advantages compared with the same generation camera, with multiple lenses exposed almost at the same time and no oblique lens. The camera has a complex imaging process whose principle will be detailed in this paper. On the other hand, the UCXp image post-processing method, including data pre-processing and orthophoto production, will be emphasized in this article. Based on the data of new Beichuan County, this paper will describe the data processing and effects

  17. Length of excitable knots

    Science.gov (United States)

    Maucher, Fabian; Sutcliffe, Paul

    2017-07-01

    In this paper, we present extensive numerical simulations of an excitable medium to study the long-term dynamics of knotted vortex strings for all torus knots up to crossing number 11. We demonstrate that FitzHugh-Nagumo evolution preserves the knot topology for all the examples presented, thereby providing a field theory approach to the study of knots. Furthermore, the evolution yields a well-defined minimal length for each knot that is comparable to the ropelength of ideal knots. We highlight the role of the medium boundary in stabilizing the length of the knot and discuss the implications beyond torus knots. We also show that there is not a unique attractor within a given knot topology.

  18. Pion nucleus scattering lengths

    International Nuclear Information System (INIS)

    Huang, W.T.; Levinson, C.A.; Banerjee, M.K.

    1971-09-01

    Soft pion theory and the Fubini-Furlan mass dispersion relations have been used to analyze the pion nucleon scattering lengths and obtain a value for the sigma commutator term. With this value and using the same principles, scattering lengths have been predicted for nuclei with mass number ranging from 6 to 23. Agreement with experiment is very good. For those who believe in the Gell-Mann-Levy sigma model, the evaluation of the commutator yields the value 0.26(m/sub σ//m/sub π/) 2 for the sigma nucleon coupling constant. The large dispersive corrections for the isosymmetric case implies that the basic idea behind many of the soft pion calculations, namely, slow variation of matrix elements from the soft pion limit to the physical pion mass, is not correct. 11 refs., 1 fig., 3 tabs

  19. Aerosol based direct-write micro-additive fabrication method for sub-mm 3D metal-dielectric structures

    International Nuclear Information System (INIS)

    Rahman, Taibur; Panat, Rahul; Renaud, Luke; Heo, Deuk; Renn, Michael

    2015-01-01

    The fabrication of 3D metal-dielectric structures at sub-mm length scale is highly important in order to realize low-loss passives and GHz wavelength antennas with applications in wearable and Internet-of-Things (IoT) devices. The inherent 2D nature of lithographic processes severely limits the available manufacturing routes to fabricate 3D structures. Further, the lithographic processes are subtractive and require the use of environmentally harmful chemicals. In this letter, we demonstrate an additive manufacturing method to fabricate 3D metal-dielectric structures at sub-mm length scale. A UV curable dielectric is dispensed from an Aerosol Jet system at 10–100 µm length scale and instantaneously cured to build complex 3D shapes at a length scale  <1 mm. A metal nanoparticle ink is then dispensed over the 3D dielectric using a combination of jetting action and tilted dispense head, also using the Aerosol Jet technique and at a length scale 10–100 µm, followed by the nanoparticle sintering. Simulation studies are carried out to demonstrate the feasibility of using such structures as mm-wave antennas. The manufacturing method described in this letter opens up the possibility of fabricating an entirely new class of custom-shaped 3D structures at a sub-mm length scale with potential applications in 3D antennas and passives. (technical note)

  20. Computed tomography dose assessment for a 160 mm wide, 320 detector row, cone beam CT scanner

    International Nuclear Information System (INIS)

    Geleijns, J; Bruin, P W de; Salvado Artells, M; Mather, R; Muramatsu, Y; McNitt-Gray, M F

    2009-01-01

    as an appropriate standard of reference for characterizing the dose of this CT scanner. A CT dose descriptor that is based on an integration length smaller than the actual beam width is preferably expressed as an (average) dose, such as D-bar 100 for the 160 mm wide cone beam CT scanner, and not as CTDI 100 .

  1. Length-weight and length-length relationships of freshwater wild ...

    African Journals Online (AJOL)

    Length-weight and length-length relationships of freshwater wild catfish Mystus bleekeri from Nala Daik, Sialkot, Pakistan. ... Linear regression analysis was used, first to compute the degree of relationship between length and weight and then among total (TL), standard (SL) and fork lengths (FL). LWR exhibited a highly ...

  2. Relativistic length agony continued

    Directory of Open Access Journals (Sweden)

    Redžić D.V.

    2014-01-01

    Full Text Available We made an attempt to remedy recent confusing treatments of some basic relativistic concepts and results. Following the argument presented in an earlier paper (Redžić 2008b, we discussed the misconceptions that are recurrent points in the literature devoted to teaching relativity such as: there is no change in the object in Special Relativity, illusory character of relativistic length contraction, stresses and strains induced by Lorentz contraction, and related issues. We gave several examples of the traps of everyday language that lurk in Special Relativity. To remove a possible conceptual and terminological muddle, we made a distinction between the relativistic length reduction and relativistic FitzGerald-Lorentz contraction, corresponding to a passive and an active aspect of length contraction, respectively; we pointed out that both aspects have fundamental dynamical contents. As an illustration of our considerations, we discussed briefly the Dewan-Beran-Bell spaceship paradox and the ‘pole in a barn’ paradox. [Projekat Ministarstva nauke Republike Srbije, br. 171028

  3. Photogrammetric Applications of Immersive Video Cameras

    OpenAIRE

    Kwiatek, K.; Tokarczyk, R.

    2014-01-01

    The paper investigates immersive videography and its application in close-range photogrammetry. Immersive video involves the capture of a live-action scene that presents a 360° field of view. It is recorded simultaneously by multiple cameras or microlenses, where the principal point of each camera is offset from the rotating axis of the device. This issue causes problems when stitching together individual frames of video separated from particular cameras, however there are ways to ov...

  4. Three-layer GSO depth-of-interaction detector for high-energy gamma camera

    Science.gov (United States)

    Yamamoto, S.; Watabe, H.; Kawachi, N.; Fujimaki, S.; Kato, K.; Hatazawa, J.

    2014-04-01

    Using Ce-doped Gd2SiO5 (GSO) of different Ce concentrations, three-layer DOI block detectors were developed to reduce the parallax error at the edges of a pinhole gamma camera for high-energy gamma photons. GSOs with Ce concentrations of 1.5 mol% (decay time ~40 ns), 0.5 mol% crystal (~60 ns), 0.4 mol% (~80 ns) were selected for the depth of interaction (DOI) detectors. These three types of GSOs were optically coupled in the depth direction, arranged in a 22×22 matrix and coupled to a flat panel photomultiplier tube (FP-PMT, Hamamatsu H8500). Sizes of these GSO cells were 1.9 mm×1.9 mm×4 mm, 1.9 mm×1.9 mm×5 mm, and 1.9 mm×1.9 mm×6 mm for 1.5 mol%, 0.5 mol%, and 0.4 mol%, respectively. With these combinations of GSOs, all spots corresponding to GSO cells were clearly resolved in the position histogram. Pulse shape spectra showed three peaks for these three decay times of GSOs. The block detector was contained in a 2-cm-thick tungsten shield, and a pinhole collimator with a 0.5-mm aperture was mounted. With pulse shape discrimination, we separated the point source images of the Cs-137 for each DOI layer. The point source image of the lower layer was detected at the most central part of the field-of-view, and the distribution was the smallest. The point source image of the higher layer was detected at the most peripheral part of the field-of-view, and the distribution was widest. With this information, the spatial resolution of the pinhole gamma camera can be improved. We conclude that DOI detection is effective for pinhole gamma cameras for high energy gamma photons.

  5. Approximations to camera sensor noise

    Science.gov (United States)

    Jin, Xiaodan; Hirakawa, Keigo

    2013-02-01

    Noise is present in all image sensor data. Poisson distribution is said to model the stochastic nature of the photon arrival process, while it is common to approximate readout/thermal noise by additive white Gaussian noise (AWGN). Other sources of signal-dependent noise such as Fano and quantization also contribute to the overall noise profile. Question remains, however, about how best to model the combined sensor noise. Though additive Gaussian noise with signal-dependent noise variance (SD-AWGN) and Poisson corruption are two widely used models to approximate the actual sensor noise distribution, the justification given to these types of models are based on limited evidence. The goal of this paper is to provide a more comprehensive characterization of random noise. We concluded by presenting concrete evidence that Poisson model is a better approximation to real camera model than SD-AWGN. We suggest further modification to Poisson that may improve the noise model.

  6. Streak camera recording of interferometer fringes

    International Nuclear Information System (INIS)

    Parker, N.L.; Chau, H.H.

    1977-01-01

    The use of an electronic high-speed camera in the streaking mode to record interference fringe motion from a velocity interferometer is discussed. Advantages of this method over the photomultiplier tube-oscilloscope approach are delineated. Performance testing and data for the electronic streak camera are discussed. The velocity profile of a mylar flyer accelerated by an electrically exploded bridge, and the jump-off velocity of metal targets struck by these mylar flyers are measured in the camera tests. Advantages of the streak camera include portability, low cost, ease of operation and maintenance, simplified interferometer optics, and rapid data analysis

  7. Decision about buying a gamma camera

    International Nuclear Information System (INIS)

    Ganatra, R.D.

    1992-01-01

    A large part of the referral to a nuclear medicine department is usually for imaging studies. Sooner or later, the nuclear medicine specialist will be called upon to make a decision about when and what type of gamma camera to buy. There is no longer an option of choosing between a rectilinear scanner and a gamma camera as the former is virtually out of the market. The decision that one has to make is when to invest in a gamma camera, and then on what basis to select the gamma camera

  8. Study of Permanent Magnet Focusing for Astronomical Camera Tubes

    Science.gov (United States)

    Long, D. C.; Lowrance, J. L.

    1975-01-01

    A design is developed of a permanent magnet assembly (PMA) useful as the magnetic focusing unit for the 35 and 70 mm (diagonal) format SEC tubes. Detailed PMA designs for both tubes are given, and all data on their magnetic configuration, size, weight, and structure of magnetic shields adequate to screen the camera tube from the earth's magnetic field are presented. A digital computer is used for the PMA design simulations, and the expected operational performance of the PMA is ascertained through the calculation of a series of photoelectron trajectories. A large volume where the magnetic field uniformity is greater than 0.5% appears obtainable, and the point spread function (PSF) and modulation transfer function(MTF) indicate nearly ideal performance. The MTF at 20 cycles per mm exceeds 90%. The weight and volume appear tractable for the large space telescope and ground based application.

  9. Performance characteristics of the novel PETRRA positron camera

    International Nuclear Information System (INIS)

    Ott, R.J.; Flower, M.; Erlandsson, K.; Reader, A.; Duxbury, D.; Bateman, J.; Stephenson, R.; Spill, E.

    2002-01-01

    The PETRRA positron camera consists of two 60 cmx40 cm annihilation photon detectors mounted on a rotating gantry. Each detector contains large BaF 2 scintillators interfaced to large area multiwire proportional chambers filled with a photo-sensitive vapour (tetrakis-(dimethylamino)-ethylene). The spatial resolution of the camera has been measured as 6.5±1.0 mm FWHM throughout the sensitive field-of-view (FoV), the timing resolution is between 7 and 10 ns FWHM and the detection efficiency for annihilation photons is ∼30% per detector. The count-rates obtained, from a 20 cm diameter by 11 cm long water filled phantom containing 90 MBq of 18 F, were ∼1.25x10 6 singles and ∼1.1x10 5 cps raw coincidences, limited only by the read-out system dead-time of ∼4 μs. The count-rate performance, sensitivity and large FoV make the camera ideal for whole-body imaging in oncology

  10. Performance characteristics of the novel PETRRA positron camera

    CERN Document Server

    Ott, R J; Erlandsson, K; Reader, A; Duxbury, D; Bateman, J; Stephenson, R; Spill, E

    2002-01-01

    The PETRRA positron camera consists of two 60 cmx40 cm annihilation photon detectors mounted on a rotating gantry. Each detector contains large BaF sub 2 scintillators interfaced to large area multiwire proportional chambers filled with a photo-sensitive vapour (tetrakis-(dimethylamino)-ethylene). The spatial resolution of the camera has been measured as 6.5+-1.0 mm FWHM throughout the sensitive field-of-view (FoV), the timing resolution is between 7 and 10 ns FWHM and the detection efficiency for annihilation photons is approx 30% per detector. The count-rates obtained, from a 20 cm diameter by 11 cm long water filled phantom containing 90 MBq of sup 1 sup 8 F, were approx 1.25x10 sup 6 singles and approx 1.1x10 sup 5 cps raw coincidences, limited only by the read-out system dead-time of approx 4 mu s. The count-rate performance, sensitivity and large FoV make the camera ideal for whole-body imaging in oncology.

  11. Family Of Calibrated Stereometric Cameras For Direct Intraoral Use

    Science.gov (United States)

    Curry, Sean; Moffitt, Francis; Symes, Douglas; Baumrind, Sheldon

    1983-07-01

    In order to study empirically the relative efficiencies of different types of orthodontic appliances in repositioning teeth in vivo, we have designed and constructed a pair of fixed-focus, normal case, fully-calibrated stereometric cameras. One is used to obtain stereo photography of single teeth, at a scale of approximately 2:1, and the other is designed for stereo imaging of the entire dentition, study casts, facial structures, and other related objects at a scale of approximately 1:8. Twin lenses simultaneously expose adjacent frames on a single roll of 70 mm film. Physical flatness of the film is ensured by the use of a spring-loaded metal pressure plate. The film is forced against a 3/16" optical glass plate upon which is etched an array of 16 fiducial marks which divide the film format into 9 rectangular regions. Using this approach, it has been possible to produce photographs which are undistorted for qualitative viewing and from which quantitative data can be acquired by direct digitization of conventional photographic enlargements. We are in the process of designing additional members of this family of cameras. All calibration and data acquisition and analysis techniques previously developed will be directly applicable to these new cameras.

  12. Influence of Digital Camera Errors on the Photogrammetric Image Processing

    Science.gov (United States)

    Sužiedelytė-Visockienė, Jūratė; Bručas, Domantas

    2009-01-01

    The paper deals with the calibration of digital camera Canon EOS 350D, often used for the photogrammetric 3D digitalisation and measurements of industrial and construction site objects. During the calibration data on the optical and electronic parameters, influencing the distortion of images, such as correction of the principal point, focal length of the objective, radial symmetrical and non-symmetrical distortions were obtained. The calibration was performed by means of the Tcc software implementing the polynomial of Chebichev and using a special test-field with the marks, coordinates of which are precisely known. The main task of the research - to determine how parameters of the camera calibration influence the processing of images, i. e. the creation of geometric model, the results of triangulation calculations and stereo-digitalisation. Two photogrammetric projects were created for this task. In first project the non-corrected and in the second the corrected ones, considering the optical errors of the camera obtained during the calibration, images were used. The results of analysis of the images processing is shown in the images and tables. The conclusions are given.

  13. discouraged by queue length

    Directory of Open Access Journals (Sweden)

    P. R. Parthasarathy

    2001-01-01

    Full Text Available The transient solution is obtained analytically using continued fractions for a state-dependent birth-death queue in which potential customers are discouraged by the queue length. This queueing system is then compared with the well-known infinite server queueing system which has the same steady state solution as the model under consideration, whereas their transient solutions are different. A natural measure of speed of convergence of the mean number in the system to its stationarity is also computed.

  14. Primary length standard adjustment

    Science.gov (United States)

    Ševčík, Robert; Guttenová, Jana

    2007-04-01

    This paper deals with problems and techniques connected with primary length standard adjusting, which includes disassembling of the device and by use of the secondary laser with collimated beam and diffraction laws successively reassembling of the laser. In the reassembling process the device was enhanced with substituting the thermal grease cooling of cold finger by copper socket cooler. This improved external cooling system enables more effective cooling of molecular iodine in the cell, which allows better pressure stability of iodine vapor and easier readjustment of the system.

  15. THE RADIO-2 mm SPECTRAL INDEX OF THE CRAB NEBULA MEASURED WITH GISMO

    International Nuclear Information System (INIS)

    Arendt, R. G.; George, J. V.; Staguhn, J. G.; Benford, D. J.; Fixsen, D. J.; Maher, S. F.; Moseley, S. H.; Sharp, E.; Wollack, E. J.; Devlin, M. J.; Dicker, S. R.; Korngut, P. M.; Irwin, K. D.; Jhabvala, C. A.; Miller, T. M.; Kovacs, A.; Mason, B. S.; Navarro, S.; Sievers, A.; Sievers, J. L.

    2011-01-01

    We present results of 2 mm observations of the Crab Nebula, obtained using the Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) bolometer camera on the IRAM 30 m telescope. Additional 3.3 mm observations with the MUSTANG bolometer array on the Green Bank Telescope are also presented. The integrated 2 mm flux density of the Crab Nebula provides no evidence for the emergence of a second synchrotron component that has been proposed. It is consistent with the radio power-law spectrum, extrapolated up to a break frequency of log (ν b [GHz]) = 2.84 ± 0.29 or ν b = 695 +651 -336 GHz. The Crab Nebula is well resolved by the ∼16.''7 beam (FWHM) of GISMO. Comparison to radio data at comparable spatial resolution enables us to confirm significant spatial variation of the spectral index between 21 cm and 2 mm. The main effect is a spectral flattening in the inner region of the Crab Nebula, correlated with the toroidal structure at the center of the nebula that is prominent in the near-IR through X-ray regime.

  16. First Light for World's Largest 'Thermometer Camera'

    Science.gov (United States)

    2007-08-01

    's atmosphere. "It is a bit as if you were trying to see stars during the day," explains Axel Weiss of the MPIfR and leader of the team that installed LABOCA on APEX. ESO PR Photo 35b/07 ESO PR Photo 35b/07 The Galactic HII Region RCW 120 This is why telescopes for this kind of astronomy must be built on high, dry sites, and why the 5100m high plateau at Chajnantor in the extremely dry Atacama Desert was chosen. Even under such optimal conditions the heat from Earth's atmosphere is still a hundred thousand times more intense than the tiny astronomical signals from distant galaxies. Very special software is required to filter such weak signals from the overwhelming disturbances. LABOCA (LArge BOlometer Camera) and its associated software were developed by MPIfR. "Since so far there are no commercial applications for such instruments we have to develop them ourselves," explains Ernst Kreysa, from MPIfR and head of the group that built the new instrument. A bolometer camera combines many tiny bolometer units into a matrix, much like the pixels are combined in a digital camera. LABOCA observes at the submillimetric wavelength of 0.87 mm, and consists of 295 channels, which are arranged in 9 concentric hexagons around a central channel. The angular resolution is 18.6 arcsec, and the total field of view is 11.4 arcmin, a remarkable size for instruments of this kind. "The first astronomical observations with LABOCA have revealed its great potential. In particular, the large number of LABOCA's detectors is an enormous improvement over earlier instruments," says Giorgio Siringo from MPIfR and member of the LABOCA team. "LABOCA is the first camera that will allow us to map large areas on the sky with high sensitivity." The Atacama Pathfinder Experiment (APEX) where LABOCA is installed is a new-technology 12-m telescope, based on an ALMA prototype antenna, and operating at the ALMA site. It has modified optics and an improved antenna surface accuracy, and is designed to take advantage of

  17. Automatic inference of geometric camera parameters and intercamera topology in uncalibrated disjoint surveillance cameras

    NARCIS (Netherlands)

    Hollander, R.J.M. den; Bouma, H.; Baan, J.; Eendebak, P.T.; Rest, J.H.C. van

    2015-01-01

    Person tracking across non-overlapping cameras and other types of video analytics benefit from spatial calibration information that allows an estimation of the distance between cameras and a relation between pixel coordinates and world coordinates within a camera. In a large environment with many

  18. Performance of Very Small Robotic Fish Equipped with CMOS Camera

    Directory of Open Access Journals (Sweden)

    Yang Zhao

    2015-10-01

    Full Text Available Underwater robots are often used to investigate marine animals. Ideally, such robots should be in the shape of fish so that they can easily go unnoticed by aquatic animals. In addition, lacking a screw propeller, a robotic fish would be less likely to become entangled in algae and other plants. However, although such robots have been developed, their swimming speed is significantly lower than that of real fish. Since to carry out a survey of actual fish a robotic fish would be required to follow them, it is necessary to improve the performance of the propulsion system. In the present study, a small robotic fish (SAPPA was manufactured and its propulsive performance was evaluated. SAPPA was developed to swim in bodies of freshwater such as rivers, and was equipped with a small CMOS camera with a wide-angle lens in order to photograph live fish. The maximum swimming speed of the robot was determined to be 111 mm/s, and its turning radius was 125 mm. Its power consumption was as low as 1.82 W. During trials, SAPPA succeeded in recognizing a goldfish and capturing an image of it using its CMOS camera.

  19. Cervical length measurement: comparison of transabdominal and transvaginal approach

    DEFF Research Database (Denmark)

    Westerway, Sue C; Pedersen, Lars Henning; Hyett, Jon

    2015-01-01

    plots showed an inverse trend with shorter cervixes. In women with a cervix TV scan measurement, TA overestimated cervical length by 12 mm (P ... accurately, particularly if the cervix is short. At 24–34 weeks, a policy of proceeding to TV scan if TA measurement is women attending with symptoms and signs......Objective: To compare transabdominal (TA) and transvaginal (TV) ultrasound assessment of cervical length at 16-41 weeks gestation. Methods: TA and TV ultrasound measurements of cervical length were made on 491 pregnancies of 16-41 weeks gestation. Cervical length was measured from internal...

  20. Ultra fast x-ray streak camera

    International Nuclear Information System (INIS)

    Coleman, L.W.; McConaghy, C.F.

    1975-01-01

    A unique ultrafast x-ray sensitive streak camera, with a time resolution of 50psec, has been built and operated. A 100A thick gold photocathode on a beryllium vacuum window is used in a modified commerical image converter tube. The X-ray streak camera has been used in experiments to observe time resolved emission from laser-produced plasmas. (author)

  1. An Open Standard for Camera Trap Data

    Directory of Open Access Journals (Sweden)

    Tavis Forrester

    2016-12-01

    Full Text Available Camera traps that capture photos of animals are a valuable tool for monitoring biodiversity. The use of camera traps is rapidly increasing and there is an urgent need for standardization to facilitate data management, reporting and data sharing. Here we offer the Camera Trap Metadata Standard as an open data standard for storing and sharing camera trap data, developed by experts from a variety of organizations. The standard captures information necessary to share data between projects and offers a foundation for collecting the more detailed data needed for advanced analysis. The data standard captures information about study design, the type of camera used, and the location and species names for all detections in a standardized way. This information is critical for accurately assessing results from individual camera trapping projects and for combining data from multiple studies for meta-analysis. This data standard is an important step in aligning camera trapping surveys with best practices in data-intensive science. Ecology is moving rapidly into the realm of big data, and central data repositories are becoming a critical tool and are emerging for camera trap data. This data standard will help researchers standardize data terms, align past data to new repositories, and provide a framework for utilizing data across repositories and research projects to advance animal ecology and conservation.

  2. Active spectral imaging nondestructive evaluation (SINDE) camera

    Energy Technology Data Exchange (ETDEWEB)

    Simova, E.; Rochefort, P.A., E-mail: eli.simova@cnl.ca [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

    2016-06-15

    A proof-of-concept video camera for active spectral imaging nondestructive evaluation has been demonstrated. An active multispectral imaging technique has been implemented in the visible and near infrared by using light emitting diodes with wavelengths spanning from 400 to 970 nm. This shows how the camera can be used in nondestructive evaluation to inspect surfaces and spectrally identify materials and corrosion. (author)

  3. CCD Color Camera Characterization for Image Measurements

    NARCIS (Netherlands)

    Withagen, P.J.; Groen, F.C.A.; Schutte, K.

    2007-01-01

    In this article, we will analyze a range of different types of cameras for its use in measurements. We verify a general model of a charged coupled device camera using experiments. This model includes gain and offset, additive and multiplicative noise, and gamma correction. It is shown that for

  4. Digital airborne camera introduction and technology

    CERN Document Server

    Sandau, Rainer

    2014-01-01

    The last decade has seen great innovations on the airborne camera. This book is the first ever written on the topic and describes all components of a digital airborne camera ranging from the object to be imaged to the mass memory device.

  5. Driving with head-slaved camera system

    NARCIS (Netherlands)

    Oving, A.B.; Erp, J.B.F. van

    2001-01-01

    In a field experiment, we tested the effectiveness of a head-slaved camera system for driving an armoured vehicle under armour. This system consists of a helmet-mounted display (HMD), a headtracker, and a motion platform with two cameras. Subjects performed several driving tasks on paved and in

  6. High resolution RGB color line scan camera

    Science.gov (United States)

    Lynch, Theodore E.; Huettig, Fred

    1998-04-01

    A color line scan camera family which is available with either 6000, 8000 or 10000 pixels/color channel, utilizes off-the-shelf lenses, interfaces with currently available frame grabbers, includes on-board pixel by pixel offset correction, and is configurable and controllable via RS232 serial port for computer controlled or stand alone operation is described in this paper. This line scan camera is based on an available 8000 element monochrome line scan camera designed by AOA for OEM use. The new color version includes improvements such as better packaging and additional user features which make the camera easier to use. The heart of the camera is a tri-linear CCD sensor with on-chip color balancing for maximum accuracy and pinned photodiodes for low lag response. Each color channel is digitized to 12 bits and all three channels are multiplexed together so that the resulting camera output video is either a 12 or 8 bit data stream at a rate of up to 24Megpixels/sec. Conversion from 12 to 8 bit, or user-defined gamma, is accomplished by on board user-defined video look up tables. The camera has two user-selectable operating modes; lows speed, high sensitivity mode or high speed, reduced sensitivity mode. The intended uses of the camera include industrial inspection, digital archiving, document scanning, and graphic arts applications.

  7. Optimization of Camera Parameters in Volume Intersection

    Science.gov (United States)

    Sakamoto, Sayaka; Shoji, Kenji; Toyama, Fubito; Miyamichi, Juichi

    Volume intersection is one of the simplest techniques for reconstructing 3-D shape from 2-D silhouettes. 3D shapes can be reconstructed from multiple view images by back-projecting them from the corresponding viewpoints and intersecting the resulting solid cones. The camera position and orientation (extrinsic camera parameters) of each viewpoint with respect to the object are needed to accomplish reconstruction. However, even a little variation in the camera parameters makes the reconstructed 3-D shape smaller than that with the exact parameters. The problem of optimizing camera parameters deals with determining exact ones based on multiple silhouette images and approximate ones. This paper examines attempts to optimize camera parameters by reconstructing a 3-D shape via the concept of volume intersection and then maximizing the volume of the 3-D shape. We have tested the proposed method to optimize the camera parameters using a VRML model. In experiments we apply the downhill simplex method to optimize them. The results of experiments show that the maximized volume of the reconstructed 3-D shape is one of the criteria to optimize camera parameters in camera arrangement like this experiment.

  8. Laser scanning camera inspects hazardous area

    International Nuclear Information System (INIS)

    Fryatt, A.; Miprode, C.

    1985-01-01

    Main operational characteristics of a new laser scanning camera are presented. The camera is intended primarily for low level high resolution viewing inside nuclear reactors. It uses a He-Ne laser beam raster; by detecting the reflected light by means of a phomultiplier, the subject under observation can be reconstructed in an electronic video store and reviewed on a conventional monitor screen

  9. Rosetta Star Tracker and Navigation Camera

    DEFF Research Database (Denmark)

    Thuesen, Gøsta

    1998-01-01

    Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera.......Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera....

  10. Centering mount for a gamma camera

    International Nuclear Information System (INIS)

    Mirkhodzhaev, A.Kh.; Kuznetsov, N.K.; Ostryj, Yu.E.

    1988-01-01

    A device for centering a γ-camera detector in case of radionuclide diagnosis is described. It permits the use of available medical coaches instead of a table with a transparent top. The device can be used for centering a detector (when it is fixed at the low end of a γ-camera) on a required area of the patient's body

  11. Securing Embedded Smart Cameras with Trusted Computing

    Directory of Open Access Journals (Sweden)

    Winkler Thomas

    2011-01-01

    Full Text Available Camera systems are used in many applications including video surveillance for crime prevention and investigation, traffic monitoring on highways or building monitoring and automation. With the shift from analog towards digital systems, the capabilities of cameras are constantly increasing. Today's smart camera systems come with considerable computing power, large memory, and wired or wireless communication interfaces. With onboard image processing and analysis capabilities, cameras not only open new possibilities but also raise new challenges. Often overlooked are potential security issues of the camera system. The increasing amount of software running on the cameras turns them into attractive targets for attackers. Therefore, the protection of camera devices and delivered data is of critical importance. In this work we present an embedded camera prototype that uses Trusted Computing to provide security guarantees for streamed videos. With a hardware-based security solution, we ensure integrity, authenticity, and confidentiality of videos. Furthermore, we incorporate image timestamping, detection of platform reboots, and reporting of the system status. This work is not limited to theoretical considerations but also describes the implementation of a prototype system. Extensive evaluation results illustrate the practical feasibility of the approach.

  12. Development of a pixelated GSO gamma camera system with tungsten parallel hole collimator for single photon imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, S.; Watabe, H.; Kanai, Y.; Shimosegawa, E.; Hatazawa, J. [Kobe City College of Technology, 8-3 Gakuen-Higashi-machi, Nishi-ku, Kobe 651-2194 (Japan); Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan); Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan); Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan) and Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan)

    2012-02-15

    Purpose: In small animal imaging using a single photon emitting radionuclide, a high resolution gamma camera is required. Recently, position sensitive photomultiplier tubes (PSPMTs) with high quantum efficiency have been developed. By combining these with nonhygroscopic scintillators with a relatively low light output, a high resolution gamma camera can become useful for low energy gamma photons. Therefore, the authors developed a gamma camera by combining a pixelated Ce-doped Gd{sub 2}SiO{sub 5} (GSO) block with a high quantum efficiency PSPMT. Methods: GSO was selected for the scintillator, because it is not hygroscopic and does not contain any natural radioactivity. An array of 1.9 mm x 1.9 mm x 7 mm individual GSO crystal elements was constructed. These GSOs were combined with a 0.1-mm thick reflector to form a 22 x 22 matrix and optically coupled to a high quantum efficiency PSPMT (H8500C-100 MOD8). The GSO gamma camera was encased in a tungsten gamma-ray shield with tungsten pixelated parallel hole collimator, and the basic performance was measured for Co-57 gamma photons (122 keV). Results: In a two-dimensional position histogram, all pixels were clearly resolved. The energy resolution was {approx}15% FWHM. With the 20-mm thick tungsten pixelated collimator, the spatial resolution was 4.4-mm FWHM 40 mm from the collimator surface, and the sensitivity was {approx}0.05%. Phantom and small animal images were successfully obtained with our developed gamma camera. Conclusions: These results confirmed that the developed pixelated GSO gamma camera has potential as an effective instrument for low energy gamma photon imaging.

  13. Lengths and Positions of the Vermiform Appendix among Sudanese Cadavers

    Directory of Open Access Journals (Sweden)

    Ehab I. El-Amin

    2015-08-01

    Full Text Available Background/objective: The anatomy of vermiform appendix displays great variations in length and position between different populations. The reports relating these variations to a specific etiological factor are few. This study aims to describe the positions and lengths of vermiform appendix among Sudanese cadavers. Methods: This descriptive study was carried out in Omdurman Teaching Hospital Morgue and Omdurman Islamic University-Sudan. Sixty Sudanese cadavers (30 male and 30 female, were dissected in the period from June 2013 to June 2014. The positions and the lengths of vermiform appendix were measured in millimeters. The data was analyzed by SPSS version 20. Results: The cadavers’ age ranged between 20 to 80 years according to their medico-legal reports. Retrocaecal position was mainly observed in 60%, pelvic in 35%, post-ileal in 3.3%, and pre-ileal in 1.7%. The lengths of the appendix was found < 69 mm in 23.3%, 70-110 mm in 60%, and > 110 mm in 16.7%, also the study showed insignificant difference between the lengths and ages (p < 0.08, and between males and females (p = 0.23. Age was the influencing factor for the positions of vermiform appendixes (p = 0.04. Conclusion: The study showed that the commonest lengths of the appendix were 70-110 mm while the common position was retrocaecal regardless to age or gender. This data should be considered in surgical removal of the inflamed appendix.

  14. Wavefront analysis for plenoptic camera imaging

    International Nuclear Information System (INIS)

    Luan Yin-Sen; Xu Bing; Yang Ping; Tang Guo-Mao

    2017-01-01

    The plenoptic camera is a single lens stereo camera which can retrieve the direction of light rays while detecting their intensity distribution. In this paper, to reveal more truths of plenoptic camera imaging, we present the wavefront analysis for the plenoptic camera imaging from the angle of physical optics but not from the ray tracing model of geometric optics. Specifically, the wavefront imaging model of a plenoptic camera is analyzed and simulated by scalar diffraction theory and the depth estimation is redescribed based on physical optics. We simulate a set of raw plenoptic images of an object scene, thereby validating the analysis and derivations and the difference between the imaging analysis methods based on geometric optics and physical optics are also shown in simulations. (paper)

  15. Lessons Learned from Crime Caught on Camera

    Science.gov (United States)

    Bernasco, Wim

    2018-01-01

    Objectives: The widespread use of camera surveillance in public places offers criminologists the opportunity to systematically and unobtrusively observe crime, their main subject matter. The purpose of this essay is to inform the reader of current developments in research on crimes caught on camera. Methods: We address the importance of direct observation of behavior and review criminological studies that used observational methods, with and without cameras, including the ones published in this issue. We also discuss the uses of camera recordings in other social sciences and in biology. Results: We formulate six key insights that emerge from the literature and make recommendations for future research. Conclusions: Camera recordings of real-life crime are likely to become part of the criminological tool kit that will help us better understand the situational and interactional elements of crime. Like any source, it has limitations that are best addressed by triangulation with other sources. PMID:29472728

  16. Lessons Learned from Crime Caught on Camera

    DEFF Research Database (Denmark)

    Lindegaard, Marie Rosenkrantz; Bernasco, Wim

    2018-01-01

    Objectives: The widespread use of camera surveillance in public places offers criminologists the opportunity to systematically and unobtrusively observe crime, their main subject matter. The purpose of this essay is to inform the reader of current developments in research on crimes caught on camera....... Methods: We address the importance of direct observation of behavior and review criminological studies that used observational methods, with and without cameras, including the ones published in this issue. We also discuss the uses of camera recordings in other social sciences and in biology. Results: We...... formulate six key insights that emerge from the literature and make recommendations for future research. Conclusions: Camera recordings of real-life crime are likely to become part of the criminological tool kit that will help us better understand the situational and interactional elements of crime. Like...

  17. Architecture of PAU survey camera readout electronics

    Science.gov (United States)

    Castilla, Javier; Cardiel-Sas, Laia; De Vicente, Juan; Illa, Joseph; Jimenez, Jorge; Maiorino, Marino; Martinez, Gustavo

    2012-07-01

    PAUCam is a new camera for studying the physics of the accelerating universe. The camera will consist of eighteen 2Kx4K HPK CCDs: sixteen for science and two for guiding. The camera will be installed at the prime focus of the WHT (William Herschel Telescope). In this contribution, the architecture of the readout electronics system is presented. Back- End and Front-End electronics are described. Back-End consists of clock, bias and video processing boards, mounted on Monsoon crates. The Front-End is based on patch panel boards. These boards are plugged outside the camera feed-through panel for signal distribution. Inside the camera, individual preamplifier boards plus kapton cable completes the path to connect to each CCD. The overall signal distribution and grounding scheme is shown in this paper.

  18. Stereo Cameras for Clouds (STEREOCAM) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Romps, David [Univ. of California, Berkeley, CA (United States); Oktem, Rusen [Univ. of California, Berkeley, CA (United States)

    2017-10-31

    The three pairs of stereo camera setups aim to provide synchronized and stereo calibrated time series of images that can be used for 3D cloud mask reconstruction. Each camera pair is positioned at approximately 120 degrees from the other pair, with a 17o-19o pitch angle from the ground, and at 5-6 km distance from the U.S. Department of Energy (DOE) Central Facility at the Atmospheric Radiation Measurement (ARM) Climate Research Facility Southern Great Plains (SGP) observatory to cover the region from northeast, northwest, and southern views. Images from both cameras of the same stereo setup can be paired together to obtain 3D reconstruction by triangulation. 3D reconstructions from the ring of three stereo pairs can be combined together to generate a 3D mask from surrounding views. This handbook delivers all stereo reconstruction parameters of the cameras necessary to make 3D reconstructions from the stereo camera images.

  19. Evaluation of Compton gamma camera prototype based on pixelated CdTe detectors.

    Science.gov (United States)

    Calderón, Y; Chmeissani, M; Kolstein, M; De Lorenzo, G

    2014-06-01

    A proposed Compton camera prototype based on pixelated CdTe is simulated and evaluated in order to establish its feasibility and expected performance in real laboratory tests. The system is based on module units containing a 2×4 array of square CdTe detectors of 10×10 mm 2 area and 2 mm thickness. The detectors are pixelated and stacked forming a 3D detector with voxel sizes of 2 × 1 × 2 mm 3 . The camera performance is simulated with Geant4-based Architecture for Medicine-Oriented Simulations(GAMOS) and the Origin Ensemble(OE) algorithm is used for the image reconstruction. The simulation shows that the camera can operate with up to 10 4 Bq source activities with equal efficiency and is completely saturated at 10 9 Bq. The efficiency of the system is evaluated using a simulated 18 F point source phantom in the center of the Field-of-View (FOV) achieving an intrinsic efficiency of 0.4 counts per second per kilobecquerel. The spatial resolution measured from the point spread function (PSF) shows a FWHM of 1.5 mm along the direction perpendicular to the scatterer, making it possible to distinguish two points at 3 mm separation with a peak-to-valley ratio of 8.

  20. Development of a Compton camera for online ion beam range verification via prompt γ detection

    Energy Technology Data Exchange (ETDEWEB)

    Aldawood, S. [LMU Munich, Garching (Germany); King Saud University, Riyadh (Saudi Arabia); Liprandi, S.; Marinsek, T.; Bortfeldt, J.; Lang, C.; Lutter, R.; Dedes, G.; Parodi, K.; Thirolf, P.G. [LMU Munich, Garching (Germany); Maier, L.; Gernhaeuser, R. [TU Munich, Garching (Germany); Kolff, H. van der [LMU Munich, Garching (Germany); TU Delft (Netherlands); Castelhano, I. [LMU Munich, Garching (Germany); University of Lisbon, Lisbon (Portugal); Schaart, D.R. [TU Delft (Netherlands)

    2015-07-01

    Precise and preferably online ion beam range verification is a mandatory prerequisite to fully exploit the advantages of hadron therapy in cancer treatment. An imaging system is being developed in Garching aiming to detect promptγ rays induced by nuclear reactions between the ion beam and biological tissue. The Compton camera prototype consists of a stack of six customized double-sided Si-strip detectors (DSSSD, 50 x 50 mm{sup 2}, 0.5 mm thick, 128 strips/side) acting as scatterer, while the absorber is formed by a monolithic LaBr{sub 3}:Ce scintillator crystal (50 x 50 x 30 mm{sup 3}) read out by a position-sensitive multi-anode photomultiplier (Hamamatsu H9500). The on going characterization of the Compton camera properties and its individual components both offline in the laboratory as well as online using proton beam are presented.

  1. Design of a Compton camera for 3D prompt-{gamma} imaging during ion beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Roellinghoff, F., E-mail: roelling@ipnl.in2p3.fr [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1 and CNRS/IN2P3, UMR 5822, IPNL, F-69622 Villeurbanne (France); INSA-Lyon Laboratory of Nondestructive Testing using Ionizing Radiation (CNDRI), F-69621 Villeurbanne Cedex (France); Richard, M.-H., E-mail: mrichard@ipnl.in2p3.fr [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1 and CNRS/IN2P3, UMR 5822, IPNL, F-69622 Villeurbanne (France); INSA-Lyon Laboratory of Nondestructive Testing using Ionizing Radiation (CNDRI), F-69621 Villeurbanne Cedex (France); Chevallier, M.; Constanzo, J.; Dauvergne, D. [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1 and CNRS/IN2P3, UMR 5822, IPNL, F-69622 Villeurbanne (France); Freud, N. [INSA-Lyon Laboratory of Nondestructive Testing using Ionizing Radiation (CNDRI), F-69621 Villeurbanne Cedex (France); Henriquet, P.; Le Foulher, F. [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1 and CNRS/IN2P3, UMR 5822, IPNL, F-69622 Villeurbanne (France); Letang, J.M. [INSA-Lyon Laboratory of Nondestructive Testing using Ionizing Radiation (CNDRI), F-69621 Villeurbanne Cedex (France); Montarou, G. [LPC, CNRS/IN2P3, Clermont-F. University (France); Ray, C.; Testa, E.; Testa, M. [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1 and CNRS/IN2P3, UMR 5822, IPNL, F-69622 Villeurbanne (France); Walenta, A.H. [Uni-Siegen, FB Physik, Emmy-Noether Campus, D-57068 Siegen (Germany)

    2011-08-21

    We investigate, by means of Geant4 simulations, a real-time method to control the position of the Bragg peak during ion therapy, based on a Compton camera in combination with a beam tagging device (hodoscope) in order to detect the prompt gamma emitted during nuclear fragmentation. The proposed set-up consists of a stack of 2 mm thick silicon strip detectors and a LYSO absorber detector. The {gamma} emission points are reconstructed analytically by intersecting the ion trajectories given by the beam hodoscope and the Compton cones given by the camera. The camera response to a polychromatic point source in air is analyzed with regard to both spatial resolution and detection efficiency. Various geometrical configurations of the camera have been tested. In the proposed configuration, for a typical polychromatic photon point source, the spatial resolution of the camera is about 8.3 mm FWHM and the detection efficiency 2.5x10{sup -4} (reconstructable photons/emitted photons in 4{pi}). Finally, the clinical applicability of our system is considered and possible starting points for further developments of a prototype are discussed.

  2. First indirect x-ray imaging tests with an 88-mm diameter single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Lumpkin, A. H. [Fermilab; Macrander, A. T. [Argonne

    2017-02-01

    Using the 1-BM-C beamline at the Advanced Photon Source (APS), we have performed the initial indirect x - ray imaging point-spread-function (PSF) test of a unique 88-mm diameter YAG:Ce single crystal of only 100 - micron thickness. The crystal was bonded to a fiber optic plat e (FOP) for mechanical support and to allow the option for FO coupling to a large format camera. This configuration resolution was compared to that of self - supported 25-mm diameter crystals, with and without an Al reflective coating. An upstream monochromator was used to select 17-keV x-rays from the broadband APS bending magnet source of synchrotron radiation. The upstream , adjustable Mo collimators were then used to provide a series of x-ray source transverse sizes from 200 microns down to about 15-20 microns (FWHM) at the crystal surface. The emitted scintillator radiation was in this case lens coupled to the ANDOR Neo sCMOS camera, and the indirect x-ray images were processed offline by a MATLAB - based image processing program. Based on single Gaussian peak fits to the x-ray image projected profiles, we observed a 10.5 micron PSF. This sample thus exhibited superior spatial resolution to standard P43 polycrystalline phosphors of the same thickness which would have about a 100-micron PSF. Lastly, this single crystal resolution combined with the 88-mm diameter makes it a candidate to support future x-ray diffraction or wafer topography experiments.

  3. Sporadic Creutzfeldt-Jakob Disease MM1+2C and MM1 are Identical in Transmission Properties.

    Science.gov (United States)

    Kobayashi, Atsushi; Matsuura, Yuichi; Iwaki, Toru; Iwasaki, Yasushi; Yoshida, Mari; Takahashi, Hitoshi; Murayama, Shigeo; Takao, Masaki; Kato, Shinsuke; Yamada, Masahito; Mohri, Shirou; Kitamoto, Tetsuyuki

    2016-01-01

    The genotype (methionine, M or valine, V) at polymorphic codon 129 of the PRNP gene and the type (1 or 2) of abnormal prion protein in the brain are the major determinants of the clinicopathological features of sporadic Creutzfeldt-Jakob disease (CJD), thus providing molecular basis for classification of sporadic CJD, that is, MM1, MM2, MV1, MV2, VV1 or VV2. In addition to these "pure" cases, "mixed" cases presenting mixed neuropathological and biochemical features have also been recognized. The most frequently observed mixed form is the co-occurrence of MM1 and MM2, namely MM1+2. However, it has remained elusive whether MM1+2 could be a causative origin of dura mater graft-associated CJD (dCJD), one of the largest subgroups of iatrogenic CJD. To test this possibility, we performed transmission experiments of MM1+2 prions and a systematic neuropathological examination of dCJD patients in the present study. The transmission properties of the MM1+2 prions were identical to those of MM1 prions because MM2 prions lacked transmissibility. In addition, the neuropathological characteristics of MM2 were totally absent in dCJD patients examined. These results suggest that MM1+2 can be a causative origin of dCJD and causes neuropathological phenotype similar to that of MM1. © 2015 International Society of Neuropathology.

  4. Towards Adaptive Virtual Camera Control In Computer Games

    DEFF Research Database (Denmark)

    Burelli, Paolo; Yannakakis, Georgios N.

    2011-01-01

    model of the camera behaviour that can be used to control camera movements based on player preferences. For this purpose, we collect eye gaze, camera and game-play data from subjects playing a 3D platform game, we cluster gaze and camera information to identify camera behaviour profiles and we employ...

  5. A Feasibility Study on the Use of a Structured Light Depth-Camera for Three-Dimensional Body Measurements of Dairy Cows in Free-Stall Barns

    Directory of Open Access Journals (Sweden)

    Andrea Pezzuolo

    2018-02-01

    Full Text Available Frequent checks on livestock’s body growth can help reducing problems related to cow infertility or other welfare implications, and recognizing health’s anomalies. In the last ten years, optical methods have been proposed to extract information on various parameters while avoiding direct contact with animals’ body, generally causes stress. This research aims to evaluate a new monitoring system, which is suitable to frequently check calves and cow’s growth through a three-dimensional analysis of their bodies’ portions. The innovative system is based on multiple acquisitions from a low cost Structured Light Depth-Camera (Microsoft Kinect™ v1. The metrological performance of the instrument is proved through an uncertainty analysis and a proper calibration procedure. The paper reports application of the depth camera for extraction of different body parameters. Expanded uncertainty ranging between 3 and 15 mm is reported in the case of ten repeated measurements. Coefficients of determination R² > 0.84 and deviations lower than 6% from manual measurements where in general detected in the case of head size, hips distance, withers to tail length, chest girth, hips, and withers height. Conversely, lower performances where recognized in the case of animal depth (R² = 0.74 and back slope (R² = 0.12.

  6. Optimal Cable Tension Distribution of the High-Speed Redundant Driven Camera Robots Considering Cable Sag and Inertia Effects

    OpenAIRE

    Yu Su; Yuanying Qiu; Peng Liu

    2014-01-01

    Camera robots are high-speed redundantly cable-driven parallel manipulators that realize the aerial panoramic photographing. When long-span cables and high maneuverability are involved, the effects of cable sags and inertias on the dynamics must be carefully dealt with. This paper is devoted to the optimal cable tension distribution (OCTD for short) of the camera robots. Firstly, each fast varying-length cable is discretized into some nodes for computing the cable inertias. Secondly, the dyna...

  7. Development of a 1.0 mm inside diameter temperature-assisted focusing precolumn for use with 2.1 mm inside diameter columns.

    Science.gov (United States)

    Groskreutz, Stephen R; Horner, Anthony R; Weber, Stephen G

    2017-11-10

    On-column solute focusing is a simple and powerful method to decrease the influence of precolumn band spreading and increase the allowable volume injected increasing sensitivity. It relies on creating conditions so that the retention factor, k', is transiently increased during the injection process. Both solvent composition and temperature control can be used to effect solute focusing. In the case of temperature, the release of the transiently delayed solute band requires increasing the temperature rapidly and with a minimum of radial thermal gradients. Thus, the focus of attention in temperature-based efforts to carry out on-column focusing has been on capillary columns. As a result, the benefits of this simple and reliable approach, temperature-assisted solute focusing or TASF, are not available to those using larger diameter columns, in particular the highly successful 2.1mm inside diameter columns. Based on considerations of thermal entrance length at the volume flow rates used with 2.1mm inside diameter columns, TASF would not be effective with such columns. However, we determined that the thermal entrance length for a 1.0mm inside diameter precolumn is sufficiently short, about 2mm, that it could work as a precolumn before a 2.1mm inside diameter analytical column. Finite element calculations demonstrate that a 1.0×20mm precolumn packed with 5μm reversed phase particles is effective at a flow rate of 250μL/min, suitable for the 2.1mm inside diameter column. Eight 1-cm 2 Peltier devices are used to heat (and cool) the precolumn. The computed axial temperature profile shows that the center of the column heats more rapidly than the ends. Based on the changes in back pressure, the full temperature transient from 5°C (focus) to 80°C (release) takes about 10s. Experimental van Deemter curves indicate that the reduced velocity in the precolumn at 250μL/min flow rate is about 50. Nonetheless, about 1000 theoretical plates are generated. When operating as a

  8. Design of an experimental four-camera setup for enhanced 3D surface reconstruction in microsurgery

    Directory of Open Access Journals (Sweden)

    Marzi Christian

    2017-09-01

    Full Text Available Future fully digital surgical visualization systems enable a wide range of new options. Caused by optomechanical limitations a main disadvantage of today’s surgical microscopes is their incapability of providing arbitrary perspectives to more than two observers. In a fully digital microscopic system, multiple arbitrary views can be generated from a 3D reconstruction. Modern surgical microscopes allow replacing the eyepieces by cameras in order to record stereoscopic videos. A reconstruction from these videos can only contain the amount of detail the recording camera system gathers from the scene. Therefore, covered surfaces can result in a faulty reconstruction for deviating stereoscopic perspectives. By adding cameras recording the object from different angles, additional information of the scene is acquired, allowing to improve the reconstruction. Our approach is to use a fixed four-camera setup as a front-end system to capture enhanced 3D topography of a pseudo-surgical scene. This experimental setup would provide images for the reconstruction algorithms and generation of multiple observing stereo perspectives. The concept of the designed setup is based on the common main objective (CMO principle of current surgical microscopes. These systems are well established and optically mature. Furthermore, the CMO principle allows a more compact design and a lowered effort in calibration than cameras with separate optics. Behind the CMO four pupils separate the four channels which are recorded by one camera each. The designed system captures an area of approximately 28mm × 28mm with four cameras. Thus, allowing to process images of 6 different stereo perspectives. In order to verify the setup, it is modelled in silico. It can be used in further studies to test algorithms for 3D reconstruction from up to four perspectives and provide information about the impact of additionally recorded perspectives on the enhancement of a reconstruction.

  9. Action Sport Cameras as an Instrument to Perform a 3D Underwater Motion Analysis.

    Science.gov (United States)

    Bernardina, Gustavo R D; Cerveri, Pietro; Barros, Ricardo M L; Marins, João C B; Silvatti, Amanda P

    2016-01-01

    Action sport cameras (ASC) are currently adopted mainly for entertainment purposes but their uninterrupted technical improvements, in correspondence of cost decreases, are going to disclose them for three-dimensional (3D) motion analysis in sport gesture study and athletic performance evaluation quantitatively. Extending this technology to sport analysis however still requires a methodologic step-forward to making ASC a metric system, encompassing ad-hoc camera setup, image processing, feature tracking, calibration and 3D reconstruction. Despite traditional laboratory analysis, such requirements become an issue when coping with both indoor and outdoor motion acquisitions of athletes. In swimming analysis for example, the camera setup and the calibration protocol are particularly demanding since land and underwater cameras are mandatory. In particular, the underwater camera calibration can be an issue affecting the reconstruction accuracy. In this paper, the aim is to evaluate the feasibility of ASC for 3D underwater analysis by focusing on camera setup and data acquisition protocols. Two GoPro Hero3+ Black (frequency: 60Hz; image resolutions: 1280×720/1920×1080 pixels) were located underwater into a swimming pool, surveying a working volume of about 6m3. A two-step custom calibration procedure, consisting in the acquisition of one static triad and one moving wand, carrying nine and one spherical passive markers, respectively, was implemented. After assessing camera parameters, a rigid bar, carrying two markers at known distance, was acquired in several positions within the working volume. The average error upon the reconstructed inter-marker distances was less than 2.5mm (1280×720) and 1.5mm (1920×1080). The results of this study demonstrate that the calibration of underwater ASC is feasible enabling quantitative kinematic measurements with accuracy comparable to traditional motion capture systems.

  10. Action Sport Cameras as an Instrument to Perform a 3D Underwater Motion Analysis.

    Directory of Open Access Journals (Sweden)

    Gustavo R D Bernardina

    Full Text Available Action sport cameras (ASC are currently adopted mainly for entertainment purposes but their uninterrupted technical improvements, in correspondence of cost decreases, are going to disclose them for three-dimensional (3D motion analysis in sport gesture study and athletic performance evaluation quantitatively. Extending this technology to sport analysis however still requires a methodologic step-forward to making ASC a metric system, encompassing ad-hoc camera setup, image processing, feature tracking, calibration and 3D reconstruction. Despite traditional laboratory analysis, such requirements become an issue when coping with both indoor and outdoor motion acquisitions of athletes. In swimming analysis for example, the camera setup and the calibration protocol are particularly demanding since land and underwater cameras are mandatory. In particular, the underwater camera calibration can be an issue affecting the reconstruction accuracy. In this paper, the aim is to evaluate the feasibility of ASC for 3D underwater analysis by focusing on camera setup and data acquisition protocols. Two GoPro Hero3+ Black (frequency: 60Hz; image resolutions: 1280×720/1920×1080 pixels were located underwater into a swimming pool, surveying a working volume of about 6m3. A two-step custom calibration procedure, consisting in the acquisition of one static triad and one moving wand, carrying nine and one spherical passive markers, respectively, was implemented. After assessing camera parameters, a rigid bar, carrying two markers at known distance, was acquired in several positions within the working volume. The average error upon the reconstructed inter-marker distances was less than 2.5mm (1280×720 and 1.5mm (1920×1080. The results of this study demonstrate that the calibration of underwater ASC is feasible enabling quantitative kinematic measurements with accuracy comparable to traditional motion capture systems.

  11. SLR digital camera for forensic photography

    Science.gov (United States)

    Har, Donghwan; Son, Youngho; Lee, Sungwon

    2004-06-01

    Forensic photography, which was systematically established in the late 19th century by Alphonse Bertillon of France, has developed a lot for about 100 years. The development will be more accelerated with the development of high technologies, in particular the digital technology. This paper reviews three studies to answer the question: Can the SLR digital camera replace the traditional silver halide type ultraviolet photography and infrared photography? 1. Comparison of relative ultraviolet and infrared sensitivity of SLR digital camera to silver halide photography. 2. How much ultraviolet or infrared sensitivity is improved when removing the UV/IR cutoff filter built in the SLR digital camera? 3. Comparison of relative sensitivity of CCD and CMOS for ultraviolet and infrared. The test result showed that the SLR digital camera has a very low sensitivity for ultraviolet and infrared. The cause was found to be the UV/IR cutoff filter mounted in front of the image sensor. Removing the UV/IR cutoff filter significantly improved the sensitivity for ultraviolet and infrared. Particularly for infrared, the sensitivity of the SLR digital camera was better than that of the silver halide film. This shows the possibility of replacing the silver halide type ultraviolet photography and infrared photography with the SLR digital camera. Thus, the SLR digital camera seems to be useful for forensic photography, which deals with a lot of ultraviolet and infrared photographs.

  12. Autonomous Multicamera Tracking on Embedded Smart Cameras

    Directory of Open Access Journals (Sweden)

    Bischof Horst

    2007-01-01

    Full Text Available There is currently a strong trend towards the deployment of advanced computer vision methods on embedded systems. This deployment is very challenging since embedded platforms often provide limited resources such as computing performance, memory, and power. In this paper we present a multicamera tracking method on distributed, embedded smart cameras. Smart cameras combine video sensing, processing, and communication on a single embedded device which is equipped with a multiprocessor computation and communication infrastructure. Our multicamera tracking approach focuses on a fully decentralized handover procedure between adjacent cameras. The basic idea is to initiate a single tracking instance in the multicamera system for each object of interest. The tracker follows the supervised object over the camera network, migrating to the camera which observes the object. Thus, no central coordination is required resulting in an autonomous and scalable tracking approach. We have fully implemented this novel multicamera tracking approach on our embedded smart cameras. Tracking is achieved by the well-known CamShift algorithm; the handover procedure is realized using a mobile agent system available on the smart camera network. Our approach has been successfully evaluated on tracking persons at our campus.

  13. UAV CAMERAS: OVERVIEW AND GEOMETRIC CALIBRATION BENCHMARK

    Directory of Open Access Journals (Sweden)

    M. Cramer

    2017-08-01

    Full Text Available Different UAV platforms and sensors are used in mapping already, many of them equipped with (sometimes modified cameras as known from the consumer market. Even though these systems normally fulfil their requested mapping accuracy, the question arises, which system performs best? This asks for a benchmark, to check selected UAV based camera systems in well-defined, reproducible environments. Such benchmark is tried within this work here. Nine different cameras used on UAV platforms, representing typical camera classes, are considered. The focus is laid on the geometry here, which is tightly linked to the process of geometrical calibration of the system. In most applications the calibration is performed in-situ, i.e. calibration parameters are obtained as part of the project data itself. This is often motivated because consumer cameras do not keep constant geometry, thus, cannot be seen as metric cameras. Still, some of the commercial systems are quite stable over time, as it was proven from repeated (terrestrial calibrations runs. Already (pre-calibrated systems may offer advantages, especially when the block geometry of the project does not allow for a stable and sufficient in-situ calibration. Especially for such scenario close to metric UAV cameras may have advantages. Empirical airborne test flights in a calibration field have shown how block geometry influences the estimated calibration parameters and how consistent the parameters from lab calibration can be reproduced.

  14. Uav Cameras: Overview and Geometric Calibration Benchmark

    Science.gov (United States)

    Cramer, M.; Przybilla, H.-J.; Zurhorst, A.

    2017-08-01

    Different UAV platforms and sensors are used in mapping already, many of them equipped with (sometimes) modified cameras as known from the consumer market. Even though these systems normally fulfil their requested mapping accuracy, the question arises, which system performs best? This asks for a benchmark, to check selected UAV based camera systems in well-defined, reproducible environments. Such benchmark is tried within this work here. Nine different cameras used on UAV platforms, representing typical camera classes, are considered. The focus is laid on the geometry here, which is tightly linked to the process of geometrical calibration of the system. In most applications the calibration is performed in-situ, i.e. calibration parameters are obtained as part of the project data itself. This is often motivated because consumer cameras do not keep constant geometry, thus, cannot be seen as metric cameras. Still, some of the commercial systems are quite stable over time, as it was proven from repeated (terrestrial) calibrations runs. Already (pre-)calibrated systems may offer advantages, especially when the block geometry of the project does not allow for a stable and sufficient in-situ calibration. Especially for such scenario close to metric UAV cameras may have advantages. Empirical airborne test flights in a calibration field have shown how block geometry influences the estimated calibration parameters and how consistent the parameters from lab calibration can be reproduced.

  15. Automatic camera tracking for remote manipulators

    International Nuclear Information System (INIS)

    Stoughton, R.S.; Martin, H.L.; Bentz, R.R.

    1984-04-01

    The problem of automatic camera tracking of mobile objects is addressed with specific reference to remote manipulators and using either fixed or mobile cameras. The technique uses a kinematic approach employing 4 x 4 coordinate transformation matrices to solve for the needed camera PAN and TILT angles. No vision feedback systems are used, as the required input data are obtained entirely from position sensors from the manipulator and the camera-positioning system. All hardware requirements are generally satisfied by currently available remote manipulator systems with a supervisory computer. The system discussed here implements linear plus on/off (bang-bang) closed-loop control with a +-2 0 deadband. The deadband area is desirable to avoid operator seasickness caused by continuous camera movement. Programming considerations for camera control, including operator interface options, are discussed. The example problem presented is based on an actual implementation using a PDP 11/34 computer, a TeleOperator Systems SM-229 manipulator, and an Oak Ridge National Laboratory (ORNL) camera-positioning system. 3 references, 6 figures, 2 tables

  16. Automatic camera tracking for remote manipulators

    Energy Technology Data Exchange (ETDEWEB)

    Stoughton, R.S.; Martin, H.L.; Bentz, R.R.

    1984-07-01

    The problem of automatic camera tracking of mobile objects is addressed with specific reference to remote manipulators and using either fixed or mobile cameras. The technique uses a kinematic approach employing 4 x 4 coordinate transformation matrices to solve for the needed camera PAN and TILT angles. No vision feedback systems are used, as the required input data are obtained entirely from position sensors from the manipulator and the camera-positioning system. All hardware requirements are generally satisfied by currently available remote manipulator systems with a supervisory computer. The system discussed here implements linear plus on/off (bang-bang) closed-loop control with a +-2-deg deadband. The deadband area is desirable to avoid operator seasickness caused by continuous camera movement. Programming considerations for camera control, including operator interface options, are discussed. The example problem presented is based on an actual implementation using a PDP 11/34 computer, a TeleOperator Systems SM-229 manipulator, and an Oak Ridge National Laboratory (ORNL) camera-positioning system. 3 references, 6 figures, 2 tables.

  17. Automatic camera tracking for remote manipulators

    Energy Technology Data Exchange (ETDEWEB)

    Stoughton, R.S.; Martin, H.L.; Bentz, R.R.

    1984-04-01

    The problem of automatic camera tracking of mobile objects is addressed with specific reference to remote manipulators and using either fixed or mobile cameras. The technique uses a kinematic approach employing 4 x 4 coordinate transformation matrices to solve for the needed camera PAN and TILT angles. No vision feedback systems are used, as the required input data are obtained entirely from position sensors from the manipulator and the camera-positioning system. All hardware requirements are generally satisfied by currently available remote manipulator systems with a supervisory computer. The system discussed here implements linear plus on/off (bang-bang) closed-loop control with a +-2/sup 0/ deadband. The deadband area is desirable to avoid operator seasickness caused by continuous camera movement. Programming considerations for camera control, including operator interface options, are discussed. The example problem presented is based on an actual implementation using a PDP 11/34 computer, a TeleOperator Systems SM-229 manipulator, and an Oak Ridge National Laboratory (ORNL) camera-positioning system. 3 references, 6 figures, 2 tables.

  18. Towards next generation 3D cameras

    Science.gov (United States)

    Gupta, Mohit

    2017-03-01

    We are in the midst of a 3D revolution. Robots enabled by 3D cameras are beginning to autonomously drive cars, perform surgeries, and manage factories. However, when deployed in the real-world, these cameras face several challenges that prevent them from measuring 3D shape reliably. These challenges include large lighting variations (bright sunlight to dark night), presence of scattering media (fog, body tissue), and optically complex materials (metal, plastic). Due to these factors, 3D imaging is often the bottleneck in widespread adoption of several key robotics technologies. I will talk about our work on developing 3D cameras based on time-of-flight and active triangulation that addresses these long-standing problems. This includes designing `all-weather' cameras that can perform high-speed 3D scanning in harsh outdoor environments, as well as cameras that recover shape of objects with challenging material properties. These cameras are, for the first time, capable of measuring detailed (<100 microns resolution) scans in extremely demanding scenarios with low-cost components. Several of these cameras are making a practical impact in industrial automation, being adopted in robotic inspection and assembly systems.

  19. Estimation of ocular volume from axial length.

    Science.gov (United States)

    Nagra, Manbir; Gilmartin, Bernard; Logan, Nicola S

    2014-12-01

    To determine which biometric parameters provide optimum predictive power for ocular volume. Sixty-seven adult subjects were scanned with a Siemens 3-T MRI scanner. Mean spherical error (MSE) (D) was measured with a Shin-Nippon autorefractor and a Zeiss IOLMaster used to measure (mm) axial length (AL), anterior chamber depth (ACD) and corneal radius (CR). Total ocular volume (TOV) was calculated from T2-weighted MRIs (voxel size 1.0 mm(3)) using an automatic voxel counting and shading algorithm. Each MR slice was subsequently edited manually in the axial, sagittal and coronal plane, the latter enabling location of the posterior pole of the crystalline lens and partitioning of TOV into anterior (AV) and posterior volume (PV) regions. Mean values (±SD) for MSE (D), AL (mm), ACD (mm) and CR (mm) were -2.62±3.83, 24.51±1.47, 3.55±0.34 and 7.75±0.28, respectively. Mean values (±SD) for TOV, AV and PV (mm(3)) were 8168.21±1141.86, 1099.40±139.24 and 7068.82±1134.05, respectively. TOV showed significant correlation with MSE, AL, PV (all p<0.001), CR (p=0.043) and ACD (p=0.024). Bar CR, the correlations were shown to be wholly attributable to variation in PV. Multiple linear regression indicated that the combination of AL and CR provided optimum R(2) values of 79.4% for TOV. Clinically useful estimations of ocular volume can be obtained from measurement of AL and CR. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  20. Performance of Laser Megajoule’s x-ray streak camera

    Energy Technology Data Exchange (ETDEWEB)

    Zuber, C., E-mail: celine.zuber@cea.fr; Bazzoli, S.; Brunel, P.; Burillo, M.; Gontier, D.; Moreau, I.; Oudot, G.; Rubbelynck, C.; Soullié, G.; Stemmler, P.; Trosseille, C. [CEA, DAM, DIF, F-91297 Arpajon (France); Fronty, J. P.; Goulmy, C. [Photonis France SAS, Avenue Roger Roncier, BP 520, 19106 Brive Cedex (France)

    2016-11-15

    A prototype of a picosecond x-ray streak camera has been developed and tested by Commissariat à l’Énergie Atomique et aux Énergies Alternatives to provide plasma-diagnostic support for the Laser Megajoule. We report on the measured performance of this streak camera, which almost fulfills the requirements: 50-μm spatial resolution over a 15-mm field in the photocathode plane, 17-ps temporal resolution in a 2-ns timebase, a detection threshold lower than 625 nJ/cm{sup 2} in the 0.05–15 keV spectral range, and a dynamic range greater than 100.

  1. [Myopia: frequency of lattice degeneration and axial length].

    Science.gov (United States)

    Martín Sánchez, M D; Roldán Pallarés, M

    2001-05-01

    To evaluate the relationship between lattice retinal degeneration and axial length of the eye in different grades of myopia. A sample of 200 eyes from 124 myopic patients was collected by chance. The average age was 34.8 years (20-50 years) and the myopia was between 0.5 and 20 diopters (D). The eyes were grouped according to the degree of refraction defect, the mean axial length of each group (Scan A) and the frequency of lattice retinal degeneration and the relationship between these variables was studied. The possible influence of age on our results was also considered. For the statistical analysis, the SAS 6.07 program with the variance analysis for quantitative variables, and chi(2) test for qualitative variables with a 5% significance were used. A multivariable linear regression model was also adjusted. The highest frequency of lattice retinal degeneration occurred in those myopia patients having more than 15 D, and also in the group of myopia patients between 3 and 6 D, but this did not show statistical significance when compared with the other myopic groups. If the axial length is assessed, a greater frequency of lattice retinal degeneration is also found when the axial length is 25-27 mm and 29-30 mm, which correspond, respectively, to myopias between 3-10 D and more than 15 D. When the multivariable linear regression model was adjusted, the axial length showed the existence of lattice retinal degeneration (beta 0.41 mm; p=0.08) adjusted by the number of diopters (beta 0.38 mm; plattice retinal degeneration was found for myopias with axial eye length between 29-30 mm (more than 15 D), and 25-27 mm (between 3-10 D).

  2. A METHOD FOR SELF-CALIBRATION IN SATELLITE WITH HIGH PRECISION OF SPACE LINEAR ARRAY CAMERA

    Directory of Open Access Journals (Sweden)

    W. Liu

    2016-06-01

    Full Text Available At present, the on-orbit calibration of the geometric parameters of a space surveying camera is usually processed by data from a ground calibration field after capturing the images. The entire process is very complicated and lengthy and cannot monitor and calibrate the geometric parameters in real time. On the basis of a large number of on-orbit calibrations, we found that owing to the influence of many factors, e.g., weather, it is often difficult to capture images of the ground calibration field. Thus, regular calibration using field data cannot be ensured. This article proposes a real time self-calibration method for a space linear array camera on a satellite using the optical auto collimation principle. A collimating light source and small matrix array CCD devices are installed inside the load system of the satellite; these use the same light path as the linear array camera. We can extract the location changes of the cross marks in the matrix array CCD to determine the real-time variations in the focal length and angle parameters of the linear array camera. The on-orbit status of the camera is rapidly obtained using this method. On one hand, the camera’s change regulation can be mastered accurately and the camera’s attitude can be adjusted in a timely manner to ensure optimal photography; in contrast, self-calibration of the camera aboard the satellite can be realized quickly, which improves the efficiency and reliability of photogrammetric processing.

  3. Trapping Elusive Cats: Using Intensive Camera Trapping to Estimate the Density of a Rare African Felid.

    Directory of Open Access Journals (Sweden)

    Eléanor Brassine

    Full Text Available Camera trapping studies have become increasingly popular to produce population estimates of individually recognisable mammals. Yet, monitoring techniques for rare species which occur at extremely low densities are lacking. Additionally, species which have unpredictable movements may make obtaining reliable population estimates challenging due to low detectability. Our study explores the effectiveness of intensive camera trapping for estimating cheetah (Acinonyx jubatus numbers. Using both a more traditional, systematic grid approach and pre-determined, targeted sites for camera placement, the cheetah population of the Northern Tuli Game Reserve, Botswana was sampled between December 2012 and October 2013. Placement of cameras in a regular grid pattern yielded very few (n = 9 cheetah images and these were insufficient to estimate cheetah density. However, pre-selected cheetah scent-marking posts provided 53 images of seven adult cheetahs (0.61 ± 0.18 cheetahs/100 km². While increasing the length of the camera trapping survey from 90 to 130 days increased the total number of cheetah images obtained (from 53 to 200, no new individuals were recorded and the estimated population density remained stable. Thus, our study demonstrates that targeted camera placement (irrespective of survey duration is necessary for reliably assessing cheetah densities where populations are naturally very low or dominated by transient individuals. Significantly our approach can easily be applied to other rare predator species.

  4. Trapping Elusive Cats: Using Intensive Camera Trapping to Estimate the Density of a Rare African Felid

    Science.gov (United States)

    Brassine, Eléanor; Parker, Daniel

    2015-01-01

    Camera trapping studies have become increasingly popular to produce population estimates of individually recognisable mammals. Yet, monitoring techniques for rare species which occur at extremely low densities are lacking. Additionally, species which have unpredictable movements may make obtaining reliable population estimates challenging due to low detectability. Our study explores the effectiveness of intensive camera trapping for estimating cheetah (Acinonyx jubatus) numbers. Using both a more traditional, systematic grid approach and pre-determined, targeted sites for camera placement, the cheetah population of the Northern Tuli Game Reserve, Botswana was sampled between December 2012 and October 2013. Placement of cameras in a regular grid pattern yielded very few (n = 9) cheetah images and these were insufficient to estimate cheetah density. However, pre-selected cheetah scent-marking posts provided 53 images of seven adult cheetahs (0.61 ± 0.18 cheetahs/100km²). While increasing the length of the camera trapping survey from 90 to 130 days increased the total number of cheetah images obtained (from 53 to 200), no new individuals were recorded and the estimated population density remained stable. Thus, our study demonstrates that targeted camera placement (irrespective of survey duration) is necessary for reliably assessing cheetah densities where populations are naturally very low or dominated by transient individuals. Significantly our approach can easily be applied to other rare predator species. PMID:26698574

  5. Camera-based driver assistance systems

    Science.gov (United States)

    Grimm, Michael

    2013-04-01

    In recent years, camera-based driver assistance systems have taken an important step: from laboratory setup to series production. This tutorial gives a brief overview on the technology behind driver assistance systems, presents the most significant functionalities and focuses on the processes of developing camera-based systems for series production. We highlight the critical points which need to be addressed when camera-based driver assistance systems are sold in their thousands, worldwide - and the benefit in terms of safety which results from it.

  6. Scintillation camera with second order resolution

    International Nuclear Information System (INIS)

    Muehllehner, G.

    1976-01-01

    A scintillation camera for use in radioisotope imaging to determine the concentration of radionuclides in a two-dimensional area is described in which means is provided for second order positional resolution. The phototubes, which normally provide only a single order of resolution, are modified to provide second order positional resolution of radiation within an object positioned for viewing by the scintillation camera. The phototubes are modified in that multiple anodes are provided to receive signals from the photocathode in a manner such that each anode is particularly responsive to photoemissions from a limited portion of the photocathode. Resolution of radioactive events appearing as an output of this scintillation camera is thereby improved

  7. A Benchmark for Virtual Camera Control

    DEFF Research Database (Denmark)

    Burelli, Paolo; Yannakakis, Georgios N.

    2015-01-01

    Automatically animating and placing the virtual camera in a dynamic environment is a challenging task. The camera is expected to maximise and maintain a set of properties — i.e. visual composition — while smoothly moving through the environment and avoiding obstacles. A large number of different....... For this reason, in this paper, we propose a benchmark for the problem of virtual camera control and we analyse a number of different problems in different virtual environments. Each of these scenarios is described through a set of complexity measures and, as a result of this analysis, a subset of scenarios...

  8. Determining camera parameters for round glassware measurements

    International Nuclear Information System (INIS)

    Baldner, F O; Costa, P B; Leta, F R; Gomes, J F S; Filho, D M E S

    2015-01-01

    Nowadays there are many types of accessible cameras, including digital single lens reflex ones. Although these cameras are not usually employed in machine vision applications, they can be an interesting choice. However, these cameras have many available parameters to be chosen by the user and it may be difficult to select the best of these in order to acquire images with the needed metrological quality. This paper proposes a methodology to select a set of parameters that will supply a machine vision system with the needed quality image, considering the measurement required of a laboratory glassware

  9. Comparison of cyclic fatigue life of nickel-titanium files: an examination using high-speed camera

    Directory of Open Access Journals (Sweden)

    Taha Özyürek

    2017-08-01

    Full Text Available Objectives To determine the actual revolutions per minute (rpm values and compare the cyclic fatigue life of Reciproc (RPC, VDW GmbH, WaveOne (WO, Dentsply Maillefer, and TF Adaptive (TFA, Axis/SybronEndo nickel-titanium (NiTi file systems using high-speed camera. Materials and Methods Twenty RPC R25 (25/0.08, 20 WO Primary (25/0.08, and 20 TFA ML 1 (25/0.08 files were employed in the present study. The cyclic fatigue tests were performed using a dynamic cyclic fatigue testing device, which has an artificial stainless steel canal with a 60° angle of curvature and a 5-mm radius of curvature. The files were divided into 3 groups (group 1, RPC R25 [RPC]; group 2, WO Primary [WO]; group 3, TF Adaptive ML 1 [TFA]. All the instruments were rotated until fracture during the cyclic fatigue test and slow-motion videos were captured using high-speed camera. The number of cycles to failure (NCF was calculated. The data were analyzed statistically using one-way analysis of variance (ANOVA, p < 0.05. Results The slow-motion videos were indicated that rpm values of the RPC, WO, and TFA groups were 180, 210, and 425, respectively. RPC (3,464.45 ± 487.58 and WO (3,257.63 ± 556.39 groups had significantly longer cyclic fatigue life compared with TFA (1,634.46 ± 300.03 group (p < 0.05. There was no significant difference in the mean length of the fractured fragments. Conclusions Within the limitation of the present study, RPC and WO NiTi files showed significantly longer cyclic fatigue life than TFA NiTi file.

  10. Crack Length Detection by Digital Image Processing

    DEFF Research Database (Denmark)

    Lyngbye, Janus; Brincker, Rune

    1990-01-01

    It is described how digital image processing is used for measuring the length of fatigue cracks. The system is installed in a Personal Computer equipped with image processing hardware and performs automated measuring on plane metal specimens used in fatigue testing. Normally one can not achieve...... a resolution better then that of the image processing equipment. To overcome this problem an extrapolation technique is used resulting in a better resolution. The system was tested on a specimen loaded with different loads. The error σa was less than 0.031 mm, which is of the same size as human measuring...

  11. PROPERTY OF THE LARGE FORMAT DIGITAL AERIAL CAMERA DMC II

    Directory of Open Access Journals (Sweden)

    K. Jacobsen

    2012-07-01

    Full Text Available Z/I Imaging introduced with the DMC II 140, 230 and 250 digital aerial cameras with a very large format CCD for the panchromatic channel. The CCDs have with 140 / 230 / 250 mega pixel a size not available in photogrammetry before. CCDs in general have a very high relative accuracy, but the overall geometry has to be checked as well as the influence of not flat CCDs. A CCD with a size of 96mm × 82mm must have a flatness or knowledge of flatness in the range of 1μm if the camera accuracy in the range of 1.3μm shall not be influenced. The DMC II cameras have been evaluated with three different flying heights leading to 5cm, 9cm and 15cm or 20cm GSD, crossing flight lines and 60% side lap. The optimal test conditions guaranteed the precise determination of the object coordinates as well as the systematic image errors. All three camera types show only very small systematic image errors, ranging in the root mean square between 0.12μm up to 0.3μm with extreme values not exceeding 1.6μm. The remaining systematic image errors, determined by analysis of the image residuals and not covered by the additional parameters, are negligible. A standard deviation of the object point heights below the GSD, determined at independent check points, even in blocks with just 20% side lap and 60% end lap is standard. Corresponding to the excellent image geometry the object point coordinates are only slightly influenced by the self calibration. For all DMCII types the handling of image models for data acquisition must not be supported by an improvement of the image coordinates by the determined systematic image errors. Such an improvement up to now is not standard for photogrammetric software packages. The advantage of a single monolithic CCD is obvious. An edge analysis of pan-sharpened DMC II 250 images resulted in factors for the effective resolution below 1.0. The result below 1.0 is only possible by contrast enhancement, but this requires with low image noise

  12. Sub-3mm spatial resolution from a large monolithic LaBr3 (Ce scintillator

    Directory of Open Access Journals (Sweden)

    Liprandi Silvia

    2017-09-01

    Full Text Available A Compton camera prototype for ion beam range monitoring via prompt (< 1 ns gamma detection in hadron therapy is being developed and characterized at the Medical Physics Department of LMU Munich. The system consists of a large (50x50x30 mm3 monolithic LaBr3(Ce scintillation crystal as absorber component to detect the multi-MeV Compton scattered photons, together with a stack of 6 double-sided silicon strip detectors (DSSSD acting as scatterer component. Key ingredient of the γ-source reconstruction is the determination of the γ-ray interaction position in the scintillator, which is read out by a 256-fold segmented multi-anode photomultiplier tube (PMT. From simulations an angular resolution of about 1.5o for the photon source reconstruction can be expected for the energy range around 3 – 5 MeV, provided that a spatial resolution of 3 mm can be reached in the absorbing scintillator [1]. Therefore, particular effort was dedicated to characterize this latter property as a function of the γ-ray energy. Intense, tightly collimated 137Cs and 60Co photon sources were used for 2D irradiation scans (step size 0.5 mm as prerequisite for studying the performance of the “k-Nearest-Neighbors” algorithm developed at TU Delft [2] (together with its variant ”Categorical Average Pattern”, CAP and extending its applicability into the energy range beyond the original 511 keV. In this paper we present our most recent interaction position analysis in the absorbing scintillator, leading to a considerably improved value for the spatial resolution: systematic studies were performed as a function of the k-NN parameters and the PMT segmentation. A trend of improving spatial resolution with increasing photon energy was confirmed, resulting in the realization of the presently optimum spatial resolution of 2.9(1 mm @1.3 MeV, thus reaching the design specifications of the Compton camera absorber. The specification goal was reached also for a reduced PMT

  13. Correlation lengths of electrostatic turbulence

    International Nuclear Information System (INIS)

    Guiziou, L.; Garbet, X.

    1995-01-01

    This document deals with correlation length of electrostatic turbulence. First, the model of drift waves turbulence is presented. Then, the radial correlation length is determined analytically with toroidal coupling and non linear coupling. (TEC). 5 refs

  14. Radial variation in fiber length of some lesser used wood species in ...

    African Journals Online (AJOL)

    computer

    2012-09-20

    Sep 20, 2012 ... In the 4th pattern, fibre length decreased from 1.49 mm in the heartwood to 0.96 mm in the transition wood followed by an increase to 1.19 mm in the .... with those being used as industrial wood species and for hardwood pulp production in ... Raw Materials Revolution and. Impact on Industrialization in ...

  15. Cervical length assessment in women with idiopathic polyhydramnios.

    Science.gov (United States)

    Hershkovitz, R; Sheiner, E; Maymon, E; Erez, O; Mazor, M

    2006-11-01

    The aims of the study were to determine cervical length among patients with polyhydramnios and to assess the relationship between the severity of polyhydramnios, cervical length and gestational age at delivery. A prospective study was designed including 92 consecutive singleton pregnancies with polyhydramnios between 24 and 40 weeks' gestation. Cervical length was measured using transvaginal sonography. Polyhydramnios was defined when amniotic fluid index (AFI) was equal to or greater than 20 cm. A single sonologist performed all the examinations of the cervical length and the AFI. The median cervical length and AFI were 37.5 (range, 7-52) mm and 28.8 (range, 20-43) cm, respectively. A significant gradual shortening of the cervical length was observed with advancing gestational age (P=0.027). No significant association was found between AFI and cervical length (P=0.24). A cut-off of 15 mm (n=5) was associated with a significantly lower gestational age at delivery (30+/-2.6 weeks vs. 37.2+/-4.2 weeks, respectively, Ppolyhydramnios have a gradual shortening of cervical length with advancing gestational age. However, this finding is not related to the severity of polyhydramnios. Copyright (c) 2006 ISUOG.

  16. Correlation lengths of electrostatic turbulence

    International Nuclear Information System (INIS)

    Guiziou, L.; Garbet, X.

    1995-01-01

    In this paper, the radial correlation length of an electrostatic drift wave turbulence is analytically determined in various regimes. The analysis relies on the calculation of a range of mode non linear interaction, which is an instantaneous correlation length. The link with the usual correlation length has not been investigated yet. (TEC). 5 refs

  17. Comparison of the effects of a new 32-gauge × 4-mm pen needle and a 32-gauge × 6-mm pen needle on glycemic control, safety, and patient ratings in Japanese adults with diabetes.

    Science.gov (United States)

    Miwa, Takashi; Itoh, Rokuro; Kobayashi, Takaaki; Tanabe, Takashi; Shikuma, Junpei; Takahashi, Tomono; Odawara, Masato

    2012-12-01

    This study was designed to evaluate two pen needles (PNs) with the same diameter but different lengths (4 mm and 6 mm) and different needle tip shapes (straight and tapered) to compare their effects on glycemic control, perceived pain, safety, patients' ease of use and preferences, and visual impression. In this prospective, open-label, controlled crossover study, 41 insulin-treated patients with type 1 or type 2 diabetes were randomized into either Group 1 (the 32-gauge × 4-mm PN was used during Study Period 1, then the 32-gauge × 6-mm PN was used during Study Period 2) or Group 2 (the order for using the PNs was reversed). The 32-gauge × 4-mm PN provided an equivalent glycemic control in diabetes patients as the 32-gauge × 6-mm PN, with an equivalent occurrence rate of adverse events. The 32-gauge × 4-mm PN was perceived as significantly less painful and rated as significantly more favorable than the 32-gauge × 6-mm PN according to the survey results on patients' ease of use and preferences and on their visual impressions. The 32-gauge × 4-mm PN was not only as safe and efficacious as the 32-gauge × 6-mm PN, but also was perceived as less painful, easier to use, and more favorable to Japanese adult patients with diabetes.

  18. Leg length change after opening wedge and closing wedge high tibial osteotomy: A meta-analysis.

    Science.gov (United States)

    Kim, Jun-Ho; Kim, Hyun-Jung; Lee, Dae-Hee

    2017-01-01

    Theoretical considerations suggest that leg length increases after opening wedge high tibial osteotomy (HTO) and decreases after closing wedge HTO; however, in vivo studies have yielded conflicting results. This meta-analysis therefore assessed changes in leg length after opening wedge and closing wedge HTO. All studies comparing pre- and postoperative leg length in patients who underwent opening and/or closing wedge HTO were included. Two reviewers independently recorded data from each study in terms of sample size as well as preoperative and postoperative leg length of open wedge and/or closed wedge HTO groups. Four studies were included in the meta-analysis. Although pooled results showed leg length changes from before to after surgery were -6.93 mm (95% confidence interval [CI]: -17.53 to 3.67 mm; P = 0.20) in opening wedge HTO and 1.97 mm (95% CI: -7.13 to 11.07 mm; P = 0.67) in closing wedge HTO, respectively, these values were statistically not significant. However, the difference in the pooled mean leg length change from before to after surgery between opening wedge and closing wedge HTO was 8 mm, a difference that was significant (95% CI: 6.53 to 9.46 mm; Pleg length was not statistically significant for either opening or closing wedge HTO. However, leg length change from before to after surgery was 8 mm greater for opening wedge HTO than for closing wedge HTO.

  19. Upgrade of the JET gamma-ray cameras

    International Nuclear Information System (INIS)

    Soare, S.; Curuia, M.; Anghel, M.; Constantin, M.; David, E.; Craciunescu, T.; Falie, D.; Pantea, A.; Tiseanu, I.; Kiptily, V.; Prior, P.; Edlington, T.; Griph, S.; Krivchenkov, Y.; Loughlin, M.; Popovichev, S.; Riccardo, V; Syme, B.; Thompson, V.; Lengar, I.; Murari, A.; Bonheure, G.; Le Guern, F.

    2007-01-01

    Full text: The JET gamma-ray camera diagnostics have already provided valuable information on the gamma-ray imaging of fast ion in JET plasmas. The applicability of gamma-ray imaging to high performance deuterium and deuterium-tritium JET discharges is strongly dependent on the fulfilment of rather strict requirements for the characterisation of the neutron and gamma-ray radiation fields. These requirements have to be satisfied within very stringent boundary conditions for the design, such as the requirement of minimum impact on the co-existing neutron camera diagnostics. The JET Gamma-Ray Cameras (GRC) upgrade project deals with these issues with particular emphasis on the design of appropriate neutron/gamma-ray filters ('neutron attenuators'). Several design versions have been developed and evaluated for the JET GRC neutron attenuators at the conceptual design level. The main design parameter was the neutron attenuation factor. The two design solutions, that have been finally chosen and developed at the level of scheme design, consist of: a) one quasi-crescent shaped neutron attenuator (for the horizontal camera) and b) two quasi-trapezoid shaped neutron attenuators (for the vertical one). The second design solution has different attenuation lengths: a short version, to be used together with the horizontal attenuator for deuterium discharges, and a long version to be used for high performance deuterium and DT discharges. Various neutron-attenuating materials have been considered (lithium hydride with natural isotopic composition and 6 Li enriched, light and heavy water, polyethylene). Pure light water was finally chosen as the attenuating material for the JET gamma-ray cameras. The neutron attenuators will be steered in and out of the detector line-of-sight by means of an electro-pneumatic steering and control system. The MCNP code was used for neutron and gamma ray transport in order to evaluate the effect of the neutron attenuators on the neutron field of the

  20. Laser-based terahertz-field-driven streak camera for the temporal characterization of ultrashort processes

    Energy Technology Data Exchange (ETDEWEB)

    Schuette, Bernd

    2011-09-15

    In this work, a novel laser-based terahertz-field-driven streak camera is presented. It allows for a pulse length characterization of femtosecond (fs) extreme ultraviolet (XUV) pulses by a cross-correlation with terahertz (THz) pulses generated with a Ti:sapphire laser. The XUV pulses are emitted by a source of high-order harmonic generation (HHG) in which an intense near-infrared (NIR) fs laser pulse is focused into a gaseous medium. The design and characterization of a high-intensity THz source needed for the streak camera is also part of this thesis. The source is based on optical rectification of the same NIR laser pulse in a lithium niobate crystal. For this purpose, the pulse front of the NIR beam is tilted via a diffraction grating to achieve velocity matching between NIR and THz beams within the crystal. For the temporal characterization of the XUV pulses, both HHG and THz beams are focused onto a gas target. The harmonic radiation creates photoelectron wavepackets which are then accelerated by the THz field depending on its phase at the time of ionization. This principle adopted from a conventional streak camera and now widely used in attosecond metrology. The streak camera presented here is an advancement of a terahertz-field-driven streak camera implemented at the Free Electron Laser in Hamburg (FLASH). The advantages of the laser-based streak camera lie in its compactness, cost efficiency and accessibility, while providing the same good quality of measurements as obtained at FLASH. In addition, its flexibility allows for a systematic investigation of streaked Auger spectra which is presented in this thesis. With its fs time resolution, the terahertz-field-driven streak camera thereby bridges the gap between attosecond and conventional cameras. (orig.)

  1. Mechanical Properties Comparing Composite Fiber Length to Amalgam.

    Science.gov (United States)

    Petersen, Richard C; Liu, Perng-Ru

    Photocure fiber-reinforced composites (FRCs) with varying chopped quartz-fiber lengths were incorporated into a dental photocure zirconia-silicate particulate-filled composite (PFC) for mechanical test comparisons with a popular commercial spherical-particle amalgam. FRC lengths included 0.5-mm, 1.0 mm, 2.0 mm, and 3.0 mm all at a constant 28.2 volume percent. Four-point fully articulated fixtures were used according to American Standards Test Methods with sample dimensions of 2×2×50 mm 3 across a 40 mm span to provide sufficient Euler flexural bending and prevent top-load compressive shear error. Mechanical properties for flexural strength, modulus, yield strength, resilience, work of fracture, critical strain energy release, critical stress intensity factor, and strain were obtained for comparison. Fiber length subsequently correlated with increasing all mechanical properties, p amalgam than all composites, all FRCs and even the PFC had higher values than amalgam for all other mechanical properties. Because amalgams provide increased longevity during clinical use compared to the standard PFCs, modulus would appear to be a mechanical property that might sufficiently reduce margin interlaminar shear stress and strain-related microcracking that could reduce failure rates. Also, since FRCs were tested with all mechanical properties that statistically significantly increased over the PFC, new avenues for future development could be provided toward surpassing amalgam in clinical longevity.

  2. Distributed Smart Cameras for Aging in Place

    National Research Council Canada - National Science Library

    Williams, Adam; Xie, Dan; Ou, Shichao; Grupen, Roderic; Hanson, Allen; Riseman, Edward

    2006-01-01

    .... The fall detector relies on features extracted from video by the camera nodes, which are sent to a central processing node where one of several machine learning techniques are applied to detect a fall...

  3. Camera Trajectory fromWide Baseline Images

    Science.gov (United States)

    Havlena, M.; Torii, A.; Pajdla, T.

    2008-09-01

    Camera trajectory estimation, which is closely related to the structure from motion computation, is one of the fundamental tasks in computer vision. Reliable camera trajectory estimation plays an important role in 3D reconstruction, self localization, and object recognition. There are essential issues for a reliable camera trajectory estimation, for instance, choice of the camera and its geometric projection model, camera calibration, image feature detection and description, and robust 3D structure computation. Most of approaches rely on classical perspective cameras because of the simplicity of their projection models and ease of their calibration. However, classical perspective cameras offer only a limited field of view, and thus occlusions and sharp camera turns may cause that consecutive frames look completely different when the baseline becomes longer. This makes the image feature matching very difficult (or impossible) and the camera trajectory estimation fails under such conditions. These problems can be avoided if omnidirectional cameras, e.g. a fish-eye lens convertor, are used. The hardware which we are using in practice is a combination of Nikon FC-E9 mounted via a mechanical adaptor onto a Kyocera Finecam M410R digital camera. Nikon FC-E9 is a megapixel omnidirectional addon convertor with 180° view angle which provides images of photographic quality. Kyocera Finecam M410R delivers 2272×1704 images at 3 frames per second. The resulting combination yields a circular view of diameter 1600 pixels in the image. Since consecutive frames of the omnidirectional camera often share a common region in 3D space, the image feature matching is often feasible. On the other hand, the calibration of these cameras is non-trivial and is crucial for the accuracy of the resulting 3D reconstruction. We calibrate omnidirectional cameras off-line using the state-of-the-art technique and Mičušík's two-parameter model, that links the radius of the image point r to the

  4. Highly Sensitive Flash LADAR Camera, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A highly sensitive 640 x 480-element flash LADAR camera will be developed that is capable of 100-Hz rates with better than 5-cm range precision. The design is based...

  5. Projector-Camera Systems for Immersive Training

    National Research Council Canada - National Science Library

    Treskunov, Anton; Pair, Jarrell

    2006-01-01

    .... These projector-camera systems effectively paint the real world with digital light. Any surface can become an interactive projection screen allowing unprepared spaces to be transformed into an immersive environment...

  6. Ge Quantum Dot Infrared Imaging Camera Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations Incorporated proposes to develop a high performance Ge quantum dots-based infrared (IR) imaging camera on Si substrate. The high sensitivity, large...

  7. A quality assurance (QA) system with a web camera for high-dose-rate brachytherapy

    International Nuclear Information System (INIS)

    Hirose, Asako; Ueda, Yoshihiro; Ohira, Shingo

    2016-01-01

    The quality assurance (QA) system that simultaneously quantifies the position and duration of an 192 Ir source (dwell position and time) was developed and the performance of this system was evaluated in high-dose-rate brachytherapy. This QA system has two functions to verify and quantify dwell position and time by using a web camera. The web camera records 30 images per second in a range from 1,425 mm to 1,505 mm. A user verifies the source position from the web camera at real time. The source position and duration were quantified with the movie using in-house software which was applied with a template-matching technique. This QA system allowed verification of the absolute position in real time and quantification of dwell position and time simultaneously. It was evident from the verification of the system that the mean of step size errors was 0.3±0.1 mm and that of dwell time errors 0.1 ± 0.0 s. Absolute position errors can be determined with an accuracy of 1.0 mm at all dwell points in three step sizes and dwell time errors with an accuracy of 0.1% in more than 10.0 s of the planned time. This system is to provide quick verification and quantification of the dwell position and time with high accuracy at various dwell positions without depending on the step size. (author)

  8. Compact Optical Technique for Streak Camera Calibration

    International Nuclear Information System (INIS)

    Curt Allen; Terence Davies; Frans Janson; Ronald Justin; Bruce Marshall; Oliver Sweningsen; Perry Bell; Roger Griffith; Karla Hagans; Richard Lerche

    2004-01-01

    The National Ignition Facility is under construction at the Lawrence Livermore National Laboratory for the U.S. Department of Energy Stockpile Stewardship Program. Optical streak cameras are an integral part of the experimental diagnostics instrumentation. To accurately reduce data from the streak cameras a temporal calibration is required. This article describes a technique for generating trains of precisely timed short-duration optical pulses that are suitable for temporal calibrations

  9. MCP gated x-ray framing camera

    Science.gov (United States)

    Cai, Houzhi; Liu, Jinyuan; Niu, Lihong; Liao, Hua; Zhou, Junlan

    2009-11-01

    A four-frame gated microchannel plate (MCP) camera is described in this article. Each frame photocathode coated with gold on the MCP is part of a transmission line with open circuit end driven by the gating electrical pulse. The gating pulse is 230 ps in width and 2.5 kV in amplitude. The camera is tested by illuminating its photocathode with ultraviolet laser pulses, 266 nm in wavelength, which shows exposure time as short as 80 ps.

  10. Imaging camera with multiwire proportional chamber

    International Nuclear Information System (INIS)

    Votruba, J.

    1980-01-01

    The camera for imaging radioisotope dislocations for use in nuclear medicine or for other applications, claimed in the patent, is provided by two multiwire lattices for the x-coordinate connected to a first coincidence circuit, and by two multiwire lattices for the y-coordinate connected to a second coincidence circuit. This arrangement eliminates the need of using a collimator and increases camera sensitivity while reducing production cost. (Ha)

  11. An imaging system for a gamma camera

    International Nuclear Information System (INIS)

    Miller, D.W.; Gerber, M.S.

    1980-01-01

    A detailed description is given of a novel gamma camera which is designed to produce superior images than conventional cameras used in nuclear medicine. The detector consists of a solid state detector (e.g. germanium) which is formed to have a plurality of discrete components to enable 2-dimensional position identification. Details of the electronic processing circuits are given and the problems and limitations introduced by noise are discussed in full. (U.K.)

  12. 3D mmWave Channel Model Proposal

    DEFF Research Database (Denmark)

    Thomas, Timothy; Nguyen, Huan Cong; R. MacCartney Jr., George

    2014-01-01

    There is growing interest in using millimeter wave (mmWave) frequencies for future access communications based on the enormous amount of available spectrum. To characterize the mmWave channel in urban areas, wideband propagation measurements at 73 GHz have recently been made in New York City. Using...... mmWave channel model is developed with special emphasis on using the ray tracer to determine elevation model parameters. The channel model includes distance-dependent elevation modeling which is critical for the expected 2D arrays which will be employed at mmWave....

  13. Axial length and cone density as assessed with adaptive optics in myopia

    Directory of Open Access Journals (Sweden)

    Supriya Dabir

    2015-01-01

    Full Text Available Aim: To assess the variations in cone mosaic in myopia and its correlation with axial length (AL. Subjects and Methods: Twenty-five healthy myopic volunteers underwent assessment of photoreceptors using adaptive optics retinal camera at 2° and 3° from the foveal center in four quadrants superior, inferior, temporal and nasal. Data was analyzed using SPSS version 17 (IBM. Multivariable regression analysis was conducted to study the relation between cone density and AL, quadrant around the fovea and eccentricity from the fovea. Results: The mean cone density was significantly lower as the eccentricity increased from 2° from the fovea to 3° (18,560 ± 5455-16,404 ± 4494/mm 2 respectively. There was also a statistically significant difference between four quadrants around the fovea. The correlation of cone density and spacing with AL showed that there was a significant inverse relation of AL with the cone density. Conclusion: In myopic patients with good visual acuity cone density around the fovea depends on the quadrant, distance from the fovea as well as the AL. The strength of the relation of AL with cone density depends on the quadrant and distance.

  14. Thermal Wave Imaging: Flying SPOT Camera.

    Science.gov (United States)

    Wang, Yiqian

    1993-01-01

    A novel "Flying Spot" infrared camera for nondestructive evaluation (NDE) and nondestructive characterization is presented. The camera scans the focal point of an unmodulated heating laser beam across the sample in a raster. The detector of the camera tracks the heating spot in the same raster, but with a time delay. The detector is thus looking at the "thermal wake" of the heating spot. The time delay between heating and detection is determined by the speed of the laser spot and the distance between it and the detector image. Since this time delay can be made arbitrarily small, the camera is capable of making thermal wave images of phenomena which occur on a very short time scale. In addition, because the heat source is a very small spot, the heat flow is fully three-dimensional. This makes the camera system sensitive to features, like tightly closed vertical cracks, which are invisible to imaging systems which employ full-field heating. A detailed theory which relates the temperature profile around the heating spot to the sample thermal properties is also described. The camera represents a potentially useful tool for measuring thermal diffusivities of materials by means of fitting the recorded temperature profiles to the theoretical curves with the diffusivity as a fitting parameter.

  15. The Use of Camera Traps in Wildlife

    Directory of Open Access Journals (Sweden)

    Yasin Uçarlı

    2013-11-01

    Full Text Available Camera traps are increasingly used in the abundance and density estimates of wildlife species. Camera traps are very good alternative for direct observation in case, particularly, steep terrain, dense vegetation covered areas or nocturnal species. The main reason for the use of camera traps is eliminated that the economic, personnel and time loss in a continuous manner at the same time in different points. Camera traps, motion and heat sensitive, can take a photo or video according to the models. Crossover points and feeding or mating areas of the focal species are addressed as a priority camera trap set locations. The population size can be finding out by the images combined with Capture-Recapture methods. The population density came out the population size divided to effective sampling area size. Mating and breeding season, habitat choice, group structures and survival rates of the focal species can be achieved from the images. Camera traps are very useful to obtain the necessary data about the particularly mysterious species with economically in planning and conservation efforts.

  16. Multi-Angle Snowflake Camera Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Stuefer, Martin [Univ. of Alaska, Fairbanks, AK (United States); Bailey, J. [Univ. of Alaska, Fairbanks, AK (United States)

    2016-07-01

    The Multi-Angle Snowflake Camera (MASC) takes 9- to 37-micron resolution stereographic photographs of free-falling hydrometers from three angles, while simultaneously measuring their fall speed. Information about hydrometeor size, shape orientation, and aspect ratio is derived from MASC photographs. The instrument consists of three commercial cameras separated by angles of 36º. Each camera field of view is aligned to have a common single focus point about 10 cm distant from the cameras. Two near-infrared emitter pairs are aligned with the camera’s field of view within a 10-angular ring and detect hydrometeor passage, with the lower emitters configured to trigger the MASC cameras. The sensitive IR motion sensors are designed to filter out slow variations in ambient light. Fall speed is derived from successive triggers along the fall path. The camera exposure times are extremely short, in the range of 1/25,000th of a second, enabling the MASC to capture snowflake sizes ranging from 30 micrometers to 3 cm.

  17. On the evolution of wafer level cameras

    Science.gov (United States)

    Welch, H.

    2011-02-01

    The introduction of small cost effective cameras based on CMOS image sensor technology has played an important role in the revolution in mobile devices of the last 10 years. Wafer-based optics manufacturing leverages the same fabrication equipment used to produce CMOS sensors. The natural integration of these two technologies allows the mass production of very low cost surface mount cameras that can fit into ever thinner mobile devices. Nano Imprint Lithography (NIL) equipment has been adapted to make precision aspheres that can be stacked using wafer bonding techniques to produce multi-element lens assemblies. This, coupled with advances in mastering technology, allows arrays of lenses with prescriptions not previously possible. A primary motivation for these methods is that it allows the consolidation of the supply chain. Image sensor manufacturers envision creating optics by simply adding layers to their existing sensor fabrication lines. Results thus far have been promising. The current alternative techniques for creating VGA cameras are discussed as well as the prime cost drivers for lens to sensor integration. Higher resolution cameras face particularly difficult challenges, but can greatly simplify the critical tilt and focus steps needed to assemble cameras that produce quality images. Finally, we discuss the future of wafer-level cameras and explore several of the novel concepts made possible by the manufacturing advantages of photolithography.

  18. Classroom multispectral imaging using inexpensive digital cameras.

    Science.gov (United States)

    Fortes, A. D.

    2007-12-01

    The proliferation of increasingly cheap digital cameras in recent years means that it has become easier to exploit the broad wavelength sensitivity of their CCDs (360 - 1100 nm) for classroom-based teaching. With the right tools, it is possible to open children's eyes to the invisible world of UVA and near-IR radiation either side of our narrow visual band. The camera-filter combinations I describe can be used to explore the world of animal vision, looking for invisible markings on flowers, or in bird plumage, for example. In combination with a basic spectroscope (such as the Project-STAR handheld plastic spectrometer, 25), it is possible to investigate the range of human vision and camera sensitivity, and to explore the atomic and molecular absorption lines from the solar and terrestrial atmospheres. My principal use of the cameras has been to teach multispectral imaging of the kind used to determine remotely the composition of planetary surfaces. A range of camera options, from 50 circuit-board mounted CCDs up to $900 semi-pro infrared camera kits (including mobile phones along the way), and various UV-vis-IR filter options will be presented. Examples of multispectral images taken with these systems are used to illustrate the range of classroom topics that can be covered. Particular attention is given to learning about spectral reflectance curves and comparing images from Earth and Mars taken using the same filter combination that it used on the Mars Rovers.

  19. High-speed CCD camera at NAOC

    Science.gov (United States)

    Zhao, Zhaowang; Wang, Wei; Liu, Yangbin

    2006-06-01

    A high speed CCD camera has been completed at the National Astronomical Observatories of China (NAOC). A Kodak CCD was used in the camera. Two output ports are used to read out CCD data and total speed achieved 60M pixels per second. The Kodak KAI-4021 image sensor is a high-performance 2Kx2K-pixel interline transfer device. The 7.4μ square pixels with micro lenses provide high sensitivity and the large full well capacity results in high dynamic range. The inter-line transfer structure provides high quality image and enables electronic shuttering for precise exposure control. The electronic shutter provides a method of precisely controlling the image exposure time without any mechanical components. The camera is controlled by a NIOS II family of embedded processors, which is Altera's second-generation soft-core embedded processor for FPGAs. The powerful embedded processors make the camera with splendid features to satisfy continuously appearing new observational requirements. This camera is very flexible and is easy to implement new special functions. Since FPGA and other peripheral logic signals are triggered by a single master clock, the whole system is perfectly synchronized. By using this technique the camera cuts off the noise dramatically.

  20. Effect of length and diameter of fiber reinforced composite post (FRC on fracture resistance of remaining tooth structure

    Directory of Open Access Journals (Sweden)

    Mahdiyeh seifi

    2013-03-01

    Full Text Available Introduction: Post and core has been considered for endodontically treated tooth, especially in cases with severe damage crowns. Recently fiber reinforced composite posts (FRC post have been used in the treatment of endodontically treated teeth. Because the length and diameter of posts are effective in stress distribution, the purpose of this study is to evaluate the effect of length and diameter of FRC post on fracture resistance. Methods: In this experimental study, 36 glass fiber posts with combination of 7mm, 9mm, and 12mm length and 1.1mm, 1.3mm and 1.5mm diameter were divided into 9 groups of 4. These posts were cemented in root canals by Panavia. Samples were tested with 45° compressive forces for the evaluation of fracture resistance. Datas were analyzed using SPSS soft ware and One- way and Two-way ANOVA analyses. Results: Fracture resistance did not increase significantly with the effect of length and diameter simultaneously (P=0.85. Samples with 12mm length and 1.5mm diameter had the greatest fracture resistance (1023/33N±239/22. The minimum fracture resistance had occurred in post with 7mm length and 1.5mm diameter (503/13N ±69/18. Fracture resistance increased significantly by increasing the length and the same diameter. Conclusion: It can be concluded that fracture resistance is affected by the length and not the diameter of FRC post.

  1. Effect of Length and Diameter of Fiber Reinforced Composite Post on Fracture Resistance of Remaining Tooth Structure

    Directory of Open Access Journals (Sweden)

    Saeid Ebrahimzadeh

    2013-03-01

    Full Text Available Introduction: Post and core has been considered for endodontically treated tooth, especially in cases with severe damage crowns. Recently fiber reinforced composite posts (FRC post have been used in the treatment of endodontically treated teeth. Because the length and diameter of posts are effective in stress distribution, the purpose of this study is to evaluate the effect of length and diameter of FRC post on fracture resistance. Methods: In this experimental study, 36 glass fiber posts with combination of 7mm, 9mm, and 12mm length and 1.1mm, 1.3mm and 1.5mm diameter were divided into 9 groups of 4. These posts were cemented in root canals by Panavia. Samples were tested with 45° compressive forces for the evaluation of fracture resistance. Datas were analyzed using SPSS soft ware and One- way and Two-way ANOVA analyses. Results: Fracture resistance did not increase significantly with the effect of length and diameter simultaneously (P=0.85. Samples with 12mm length and 1.5mm diameter had the greatest fracture resistance (1023/33N±239/22. The minimum fracture resistance had occurred in post with 7mm length and 1.5mm diameter (503/13N ±69/18. Fracture resistance increased significantly by increasing the length and the same diameter. Conclusion: It can be concluded that fracture resistance is affected by the length and not the diameter of FRC post.

  2. The neutron small-angle camera D11 at the high-flux reactor, Grenoble

    International Nuclear Information System (INIS)

    Ibel, K.

    1976-01-01

    The neutron small-angle scattering system at the high-flux reactor in Grenoble consists of three major parts: the supply of cold neutrons via bent neutron guides; the small-angle camera D11; and the data handling facilities. The camera D11 has an overall length of 80 m. The effective length of the camera is variable. The full length of the collimator before the fixed sample position can be reduced by movable neutron guides; the second flight path of 40 m full length contains detector sites in various positions. Thus a large range of momentum transfers can be used with the same relative resolution. Scattering angles between 5 x 10 -4 and 0.5 rad and neutron wavelengths from 0.2 to 2.0 nm are available. A large-area position-sensitive detector is used which allows simultaneous recording of intensities scattered at different angles; it is a multiwire proportional chamber. 3808 elements of 1 cm 2 are arranged in a two-dimensional matrix. (Auth.)

  3. Two-dimensional displacement measurement using static close range photogrammetry and a single fixed camera

    Directory of Open Access Journals (Sweden)

    Abdallah M. Khalil

    2011-09-01

    Full Text Available This work describes a simple approach to measure the displacement of a moving object in two directions simultaneously. The proposed approach is based on static close range photogrammetry with a single camera and the well-known collinearity equations. The proposed approach requires neither multi-camera synchronization nor mutual camera calibration. It requires no prior knowledge of the kinematic and kinetic data of the moving object. The proposed approach was used to evaluate predefined two-dimensional displacements of a moving object. The root mean square values of the differences between the predefined and evaluated displacements in the two directions are 0.11 and 0.02 mm.

  4. Fourier transform infrared absorption spectroscopy characterization of gaseous atmospheric pressure plasmas with 2 mm spatial resolution

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, G. [Laboratoire d' Ingenierie de Surface, Centre de Recherche sur les Materiaux Avances, Departement de genie des mines, de la metallurgie et des materiaux, Universite Laval, 1065, avenue de la Medecine, Quebec G1V 0A6 (Canada); Centre de recherche du CHUQ, Hopital St Francois d' Assise, 10, rue de l' Espinay, local E0-165, Quebec G1L 3L5 (Canada); Vallade, J. [Laboratoire Procedes, Materiaux et Energie Solaire, PROMES, CNRS, Technosud, Rambla de la Thermodynamique, F-66100 Perpignan (France); Agence de l' environnement et de la Ma Latin-Small-Letter-Dotless-I -carettrise de l' Energie, 20, avenue du Gresille, BP 90406, F-49004 Angers Cedex 01 (France); Bazinette, R.; Hernandez, E.; Hernandez, G.; Massines, F. [Laboratoire Procedes, Materiaux et Energie Solaire, PROMES, CNRS, Technosud, Rambla de la Thermodynamique, F-66100 Perpignan (France); Nijnatten, P. van [OMT Solutions bv, High Tech Campus 9, 5656AE Eindhoven (Netherlands)

    2012-10-15

    This paper describes an optical setup built to record Fourier transform infrared (FTIR) absorption spectra in an atmospheric pressure plasma with a spatial resolution of 2 mm. The overall system consisted of three basic parts: (1) optical components located within the FTIR sample compartment, making it possible to define the size of the infrared beam (2 mm Multiplication-Sign 2 mm over a path length of 50 mm) imaged at the site of the plasma by (2) an optical interface positioned between the spectrometer and the plasma reactor. Once through the plasma region, (3) a retro-reflector module, located behind the plasma reactor, redirected the infrared beam coincident to the incident path up to a 45 Degree-Sign beamsplitter to reflect the beam toward a narrow-band mercury-cadmium-telluride detector. The antireflective plasma-coating experiments performed with ammonia and silane demonstrated that it was possible to quantify 42 and 2 ppm of these species in argon, respectively. In the case of ammonia, this was approximately three times less than this gas concentration typically used in plasma coating experiments while the silane limit of quantification was 35 times lower. Moreover, 70% of the incoming infrared radiation was focused within a 2 mm width at the site of the plasma, in reasonable agreement with the expected spatial resolution. The possibility of reaching this spatial resolution thus enabled us to measure the gaseous precursor consumption as a function of their residence time in the plasma.

  5. Length-force characteristics of the aponeurosis in the passive and active muscle condition and in the isolated condition

    NARCIS (Netherlands)

    Zuurbier, C. J.; Everard, A. J.; van der Wees, P.; Huijing, P. A.

    1994-01-01

    Length behaviour of the entire and designated parts of the proximal aponeurosis of the unipennate gastrocnemius medialis (GM) muscle of the rat was examined at muscle lengths ranging form muscle slack length to 4 mm above muscle optimum length in the passive and active (isometric contractions)

  6. Influence of fiber length on flexural and impact properties of Zalacca Midrib fiber/HDPE by compression molding

    Science.gov (United States)

    Pamungkas, Agil Fitri; Ariawan, Dody; Surojo, Eko; Triyono, Joko

    2018-02-01

    The aim of the research is to investigate the effect of fiber length on the flexural and impact properties of the composite of Zalacca Midrib Fiber (ZMF)/HDPE. The process of making composite was using compression molding method. The variation of fiber length were 1 mm, 3 mm, 5 mm, 7 mm and 9 mm, at 30% fiber volume fraction. The flexural and impact test according to ASTM D790 and ASTM D5941, respectively. Observing fracture surface was examained by using Scanning Electron Microscopy (SEM). The results showed that the flexural and impact strengths would be increase with the increase of fiber length.

  7. Calcaneotalar ratio: a new concept in the estimation of the length of the calcaneus.

    Science.gov (United States)

    David, Vikram; Stephens, Terry J; Kindl, Radek; Ang, Andy; Tay, Wei-Han; Asaid, Rafik; McCullough, Keith

    2015-01-01

    Maintaining the calcaneal length after calcaneal fractures is vital to restoring the normal biomechanics of the foot, because it acts as an important lever arm to the plantarflexors of the foot. However, estimation of the length of the calcaneus to be reconstructed in comminuted calcaneal fractures can be difficult. We propose a new method to reliably estimate the calcaneal length radiographically by defining the calcaneotalar length ratio. A total of 100 ankle radiographs with no fracture in the calcaneus or talus taken in skeletally mature patients were reviewed by 6 observers. The anteroposterior lengths of the calcaneus and talus were measured, and the calcaneotalar length ratio was determined. The ratio was then used to estimate the length of the calcaneus. Interobserver reliability was determined using Cronbach's α coefficient and Pearson's correlation coefficient. The mean length of the calcaneus was 75 ± 0.6 mm, and the mean length of the talus was 59 ± 0.5 mm. The calcaneotalar ratio was 1.3. Using this ratio and multiplying it by the talar length, the mean average estimated length of the calcaneus was within 0.7 mm of the known calcaneal length. Cronbach's α coefficient and Pearson's correlation coefficient showed excellent interobserver reliability. The proposed calcaneotalar ratio is a new and reliable method to radiographically estimate the normal length of the calcaneus when reconstructing the calcaneus. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Call-graph-based inter-class MM path generation

    Science.gov (United States)

    He, Wei; Zhao, Ruilian

    2012-01-01

    Inter-class testing is the testing of classes for composing an object-oriented system or subsystem during integration. MM Path is defined as an interleaved sequence of method executions linked by messages. It represents the interactions between methods in object-oriented software well, hence fits for object-oriented integration testing. However, the current MM Path generation methods only support intra-class testing. In this paper, a call-graph-based approach is proposed to promote MM Path automatic generation from intra-class to inter-class level. The approach is evaluated by controlled experiments on 12 Java benchmark programs with two typical call graph construction algorithms, Class Hierarchy Analysis and Anderson's Points-to Analysis. Then, the impact of the two algorithms on inter-class MM path generation efficiency is studied. The result shows that our approach is practicable and Anderson's Points-to Analysis outperforms Class Hierarchy Analysis for inter-class MM Path generation.

  9. Imaging performance of a multiwire proportional-chamber positron camera

    International Nuclear Information System (INIS)

    Perez-Mandez, V.; Del Guerra, A.; Nelson, W.R.; Tam, K.C.

    1982-08-01

    A new design - fully three-dimensional - Positron Camera is presented, made of six MultiWire Proportional Chamber modules arranged to form the lateral surface of a hexagonal prism. A true coincidence rate of 56000 c/s is expected with an equal accidental rate for a 400 μCi activity uniformly distributed in a approx. 3 l water phantom. A detailed Monte Carlo program has been used to investigate the dependence of the spatial resolution on the geometrical and physical parameters. A spatial resolution of 4.8 mm FWHM has been obtained for a 18 F point-like source in a 10 cm radius water phantom. The main properties of the limited angle reconstruction algorithms are described in relation to the proposed detector geometry

  10. Development of the LBNL positron emission mammography camera

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Jennifer S.; Choong, Woon-Seng; Wang, Jimmy; Maltz, Jonathon S.; Qi, Jinyi; Mandelli, Emanuele; Moses, William W.

    2002-12-19

    We present the construction status of the LBNL Positron Emission Mammography (PEM) camera, which utilizes a PET detector module with depth of interaction measurement consisting of 64 LSO crystals (3x3x30 mm3) coupled on one end to a single photomultiplier tube (PMT) and on the opposite end to a 64 pixel array of silicon photodiodes (PDs). The PMT provides an accurate timing pulse, the PDs identify the crystal of interaction, the sum provides a total energy signal, and the PD/(PD+PMT) ratio determines the depth of interaction. We have completed construction of all 42 PEM detector modules. All data acquisition electronics have been completed, fully tested and loaded onto the gantry. We have demonstrated that all functions of the custom IC work using the production rigid-flex boards and data acquisition system. Preliminary detector module characterization and coincidence data have been taken using the production system, including initial images.

  11. Framing-camera tube developed for sub-100-ps range

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    A new framing-camera tube, developed by Electronics Engineering, is capable of recording two-dimensional image frames with high spatial resolution in the sub-100-ps range. Framing is performed by streaking a two-dimensional electron image across narrow slits; the resulting electron-line images from the slits are restored into a framed image by a restorer deflector operating synchronously with the dissector deflector. We have demonstrated its performance in a prototype tube by recording 125-ps-duration framed images of 2.5-mm patterns. The limitation in the framing speed is in the external electronic drivers for the deflectors and not in the tube design characteristics. Shorter frame durations (below 100 ps) can be obtained by use of faster deflection drivers

  12. Performance evaluation of MACACO: a multilayer Compton camera

    Science.gov (United States)

    Muñoz, Enrique; Barrio, John; Etxebeste, Ane; Ortega, Pablo G.; Lacasta, Carlos; Oliver, Josep F.; Solaz, Carles; Llosá, Gabriela

    2017-09-01

    Compton imaging devices have been proposed and studied for a wide range of applications. We have developed a Compton camera prototype which can be operated with two or three detector layers based on monolithic lanthanum bromide (LaBr3 ) crystals coupled to silicon photomultipliers (SiPMs), to be used for proton range verification in hadron therapy. In this work, we present the results obtained with our prototype in laboratory tests with radioactive sources and in simulation studies. Images of a 22 Na and an 88 Y radioactive sources have been successfully reconstructed. The full width half maximum of the reconstructed images is below 4 mm for a 22 Na source at a distance of 5 cm.

  13. Soft x-ray streak cameras

    International Nuclear Information System (INIS)

    Stradling, G.L.

    1988-01-01

    This paper is a discussion of the development and of the current state of the art in picosecond soft x-ray streak camera technology. Accomplishments from a number of institutions are discussed. X-ray streak cameras vary from standard visible streak camera designs in the use of an x-ray transmitting window and an x-ray sensitive photocathode. The spectral sensitivity range of these instruments includes portions of the near UV and extends from the subkilovolt x- ray region to several tens of kilovolts. Attendant challenges encountered in the design and use of x-ray streak cameras include the accommodation of high-voltage and vacuum requirements, as well as manipulation of a photocathode structure which is often fragile. The x-ray transmitting window is generally too fragile to withstand atmospheric pressure, necessitating active vacuum pumping and a vacuum line of sight to the x-ray signal source. Because of the difficulty of manipulating x-ray beams with conventional optics, as is done with visible light, the size of the photocathode sensing area, access to the front of the tube, the ability to insert the streak tube into a vacuum chamber and the capability to trigger the sweep with very short internal delay times are issues uniquely relevant to x-ray streak camera use. The physics of electron imaging may place more stringent limitations on the temporal and spatial resolution obtainable with x-ray photocathodes than with the visible counterpart. Other issues which are common to the entire streak camera community also concern the x-ray streak camera users and manufacturers

  14. [Ultrasonographic evaluation of the uterine cervix length remaining after LOOP-excision].

    Science.gov (United States)

    Robert, A-L; Nicolas, F; Lavoué, V; Henno, S; Mesbah, H; Porée, P; Levêque, J

    2014-04-01

    To assess whether there is a correlation between the length of a conization specimen and the length of the cervix measured by vaginal ultrasonography after the operation Prospective observational study including patients less than 45 years with measurement of cervical length before and the day of the conization, and measuring the histological length of the specimen. Among the 40 patients enrolled, the average ultrasound measurements before conization was 26.9 mm (± 4.9 mm) against 18.1mm (± 4.4mm) after conization with a mean difference of 8.8mm (± 2.4mm) (difference statistically significant Pcervix length remove by loop-excision in our series is 33% (± 8.5%). A good correlation between the measurements of the specimen and the cervical ultrasound length before and after conization was found, as a significant reduction in cervical length after conization. The precise length of the specimen should be known in case of pregnancy and the prevention of prematurity due to conization rests on selected indications and efficient surgical technique. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  15. A directional fast neutron detector using scintillating fibers and an intensified CCD camera system

    International Nuclear Information System (INIS)

    Holslin, Daniel; Armstrong, A.W.; Hagan, William; Shreve, David; Smith, Scott

    1994-01-01

    We have been developing and testing a scintillating fiber detector (SFD) for use as a fast neutron sensor which can discriminate against neutrons entering at angles non-parallel to the fiber axis (''directionality''). The detector/convertor component is a fiber bundle constructed of plastic scintillating fibers each measuring 10 cm long and either 0.3 mm or 0.5 mm in diameter. Extensive Monte Carlo simulations were made to optimize the bundle response to a range of fast neutron energies and to intense fluxes of high energy gamma-rays. The bundle is coupled to a set of gamma-ray insenitive electro-optic intensifiers whose output is viewed by a CCD camera directly coupled to the intensifiers. Two types of CCD cameras were utilized: 1) a standard, interline RS-170 camera with electronic shuttering and 2) a high-speed (up to 850 frame/s) field-transfer camera. Measurements of the neutron detection efficiency and directionality were made using 14 MeV neutrons, and the response to gamma-rays was performed using intense fluxes from radioisotopic sources (up to 20 R/h). Recently, the detector was constructed and tested using a large 10 cm by 10 cm square fiber bundle coupled to a 10 cm diameter GEN I intensifier tube. We present a description of the various detector systems and report the results of experimental tests. ((orig.))

  16. Length-weight relationships of fishes from South African estuaries

    CSIR Research Space (South Africa)

    Harrison, TD

    2001-02-01

    Full Text Available in the ?eld, measured to the nearest mm SL and weighed to the nearest 1.0g using a Bonso model 323 balance (Bonso Electronics Intl, Hong Kong). The length?weight relationships of all species collected were determined by the expression w ? alb, where w...

  17. Amplitude modulation drive to rectangular-plate linear ultrasonic motors with vibrators dimensions 8 mm x 2.16 mm X 1 mm.

    Science.gov (United States)

    Ming, Yang; Hanson, Ben; Levesley, Martin C; Walker, Peter G; Watterson, Kevin G

    2006-12-01

    In this paper, to exploit the contribution from not only the stators but also from other parts of miniature ultrasonic motors, an amplitude modulation drive is proposed to drive a miniature linear ultrasonic motor consisting of two rectangular piezoelectric ceramic plates. Using finite-element software, the first longitudinal and second lateral-bending frequencies of the vibrator are shown to be very close when its dimensions are 8 mm x 2.16 mm x 1 mm. So one single frequency power should be able to drive the motor. However, in practice the motor is found to be hard to move with a single frequency power because of its small vibration amplitudes and big frequency difference between its longitudinal and bending resonance, which is induced by the boundary condition variation. To drive the motor effectively, an amplitude modulation drive is used by superimposing two signals with nearly the same frequencies, around the resonant frequency of the vibrators of the linear motor. When the amplitude modulation frequency is close to the resonant frequency of the vibrator's surroundings, experimental results show that the linear motor can move back and forward with a maximum thrust force (over 0.016 N) and a maximum velocity (over 50 mm/s).

  18. Entry zone of iliac screw fixation to maintain proper entry width and screw length.

    Science.gov (United States)

    Park, Soo-An; Kwak, Dai-Soon; You, Sung-Lim

    2015-11-01

    To evaluate the entry zone of iliac screw fixation to maintain proper entry width and screw length. Computed tomography images of pelvic bones from 90 human cadavers were reconstructed into 3-dimensional models. In each model, a sectional image crossing the posterior superior iliac spine (PSIS) and anterior inferior iliac spine (AIIS) and consecutive sectional images up to 20 mm superiorly and inferiorly from the PSIS with 1-mm intervals aiming the AIIS were obtained. One virtual iliac screw with 10-mm diameter was introduced onto the PSIS at the middle and at the lateral and medial 1/4 points on the prominence of the posterior iliac spine. The entry width of the bony prominence and the corresponding maximal screw length available were evaluated for each entry point. The entry width was smallest on the inferior 20 mm (4.7 ± 3.0 mm) and gradually increased up to the superior 10 mm (19.1 ± 3.9 mm) sectional images. The maximal screw length was smallest on the superior 20 mm (76.7 ± 39.7 mm) and gradually increased down to the inferior 10 mm (112.3 ± 15.1 mm) sectional images. The maximal screw lengths were significantly greatest at the most medial point and smallest at the most lateral point on the superior 20- and 10-mm sectional images and at the PSIS. The iliac screw fixation entry zone to maintain proper screw length and entry width is outlined from 20 mm superiorly to 10 mm inferiorly from the PSIS and is located more medially from the prominence of the posterior iliac spine.

  19. Characterization of SWIR cameras by MRC measurements

    Science.gov (United States)

    Gerken, M.; Schlemmer, H.; Haan, Hubertus A.; Siemens, Christofer; Münzberg, M.

    2014-05-01

    Cameras for the SWIR wavelength range are becoming more and more important because of the better observation range for day-light operation under adverse weather conditions (haze, fog, rain). In order to choose the best suitable SWIR camera or to qualify a camera for a given application, characterization of the camera by means of the Minimum Resolvable Contrast MRC concept is favorable as the MRC comprises all relevant properties of the instrument. With the MRC known for a given camera device the achievable observation range can be calculated for every combination of target size, illumination level or weather conditions. MRC measurements in the SWIR wavelength band can be performed widely along the guidelines of the MRC measurements of a visual camera. Typically measurements are performed with a set of resolution targets (e.g. USAF 1951 target) manufactured with different contrast values from 50% down to less than 1%. For a given illumination level the achievable spatial resolution is then measured for each target. The resulting curve is showing the minimum contrast that is necessary to resolve the structure of a target as a function of spatial frequency. To perform MRC measurements for SWIR cameras at first the irradiation parameters have to be given in radiometric instead of photometric units which are limited in their use to the visible range. In order to do so, SWIR illumination levels for typical daylight and twilight conditions have to be defined. At second, a radiation source is necessary with appropriate emission in the SWIR range (e.g. incandescent lamp) and the irradiance has to be measured in W/m2 instead of Lux = Lumen/m2. At third, the contrast values of the targets have to be calibrated newly for the SWIR range because they typically differ from the values determined for the visual range. Measured MRC values of three cameras are compared to the specified performance data of the devices and the results of a multi-band in-house designed Vis-SWIR camera

  20. How to Build Your Own Document Camera for around $100

    Science.gov (United States)

    Van Orden, Stephen

    2010-01-01

    Document cameras can have great utility in second language classrooms. However, entry-level consumer document cameras start at around $350. This article describes how the author built three document cameras and offers suggestions for how teachers can successfully build their own quality document camera using a webcam for around $100.

  1. Advanced system for Gamma Cameras modernization

    International Nuclear Information System (INIS)

    Osorio Deliz, J. F.; Diaz Garcia, A.; Arista Romeu, E. J.

    2015-01-01

    Analog and digital gamma cameras still largely used in developing countries. Many of them rely in old hardware electronics, which in many cases limits their use in actual nuclear medicine diagnostic studies. Consequently, there are different worldwide companies that produce medical equipment engaged into a partial or total Gamma Cameras modernization. Present work has demonstrated the possibility of substitution of almost entire signal processing electronics placed at inside a Gamma Camera detector head by a digitizer PCI card. this card includes four 12 Bits Analog-to-Digital-Converters of 50 MHz speed. It has been installed in a PC and controlled through software developed in Lab View. Besides, there were done some changes to the hardware inside the detector head including redesign of the Orientation Display Block (ODA card). Also a new electronic design was added to the Microprocessor Control Block (MPA card) which comprised a PIC micro controller acting as a tuning system for individual Photomultiplier Tubes. The images, obtained by measurement of 99m Tc point radioactive source, using modernized camera head demonstrate its overall performance. The system was developed and tested in an old Gamma Camera ORBITER II SIEMENS GAMMASONIC at National Institute of Oncology and Radiobiology (INOR) under CAMELUD project supported by National Program PNOULU and IAEA . (Author)

  2. Wired and Wireless Camera Triggering with Arduino

    Science.gov (United States)

    Kauhanen, H.; Rönnholm, P.

    2017-10-01

    Synchronous triggering is an important task that allows simultaneous data capture from multiple cameras. Accurate synchronization enables 3D measurements of moving objects or from a moving platform. In this paper, we describe one wired and four wireless variations of Arduino-based low-cost remote trigger systems designed to provide a synchronous trigger signal for industrial cameras. Our wireless systems utilize 315 MHz or 434 MHz frequencies with noise filtering capacitors. In order to validate the synchronization accuracy, we developed a prototype of a rotating trigger detection system (named RoTriDeS). This system is suitable to detect the triggering accuracy of global shutter cameras. As a result, the wired system indicated an 8.91 μs mean triggering time difference between two cameras. Corresponding mean values for the four wireless triggering systems varied between 7.92 and 9.42 μs. Presented values include both camera-based and trigger-based desynchronization. Arduino-based triggering systems appeared to be feasible, and they have the potential to be extended to more complicated triggering systems.

  3. Design of Endoscopic Capsule With Multiple Cameras.

    Science.gov (United States)

    Gu, Yingke; Xie, Xiang; Li, Guolin; Sun, Tianjia; Wang, Dan; Yin, Zheng; Zhang, Pengfei; Wang, Zhihua

    2015-08-01

    In order to reduce the miss rate of the wireless capsule endoscopy, in this paper, we propose a new system of the endoscopic capsule with multiple cameras. A master-slave architecture, including an efficient bus architecture and a four level clock management architecture, is applied for the Multiple Cameras Endoscopic Capsule (MCEC). For covering more area of the gastrointestinal tract wall with low power, multiple cameras with a smart image capture strategy, including movement sensitive control and camera selection, are used in the MCEC. To reduce the data transfer bandwidth and power consumption to prolong the MCEC's working life, a low complexity image compressor with PSNR 40.7 dB and compression rate 86% is implemented. A chipset is designed and implemented for the MCEC and a six cameras endoscopic capsule prototype is implemented by using the chipset. With the smart image capture strategy, the coverage rate of the MCEC prototype can achieve 98% and its power consumption is only about 7.1 mW.

  4. Occluded object imaging via optimal camera selection

    Science.gov (United States)

    Yang, Tao; Zhang, Yanning; Tong, Xiaomin; Ma, Wenguang; Yu, Rui

    2013-12-01

    High performance occluded object imaging in cluttered scenes is a significant challenging task for many computer vision applications. Recently the camera array synthetic aperture imaging is proved to be an effective way to seeing object through occlusion. However, the imaging quality of occluded object is often significantly decreased by the shadows of the foreground occluder. Although some works have been presented to label the foreground occluder via object segmentation or 3D reconstruction, these methods will fail in the case of complicated occluder and severe occlusion. In this paper, we present a novel optimal camera selection algorithm to solve the above problem. The main characteristics of this algorithm include: (1) Instead of synthetic aperture imaging, we formulate the occluded object imaging problem as an optimal camera selection and mosaicking problem. To the best of our knowledge, our proposed method is the first one for occluded object mosaicing. (2) A greedy optimization framework is presented to propagate the visibility information among various depth focus planes. (3) A multiple label energy minimization formulation is designed in each plane to select the optimal camera. The energy is estimated in the synthetic aperture image volume and integrates the multi-view intensity consistency, previous visibility property and camera view smoothness, which is minimized via Graph cuts. We compare our method with the state-of-the-art synthetic aperture imaging algorithms, and extensive experimental results with qualitative and quantitative analysis demonstrate the effectiveness and superiority of our approach.

  5. Designing Camera Networks by Convex Quadratic Programming

    KAUST Repository

    Ghanem, Bernard

    2015-05-04

    ​In this paper, we study the problem of automatic camera placement for computer graphics and computer vision applications. We extend the problem formulations of previous work by proposing a novel way to incorporate visibility constraints and camera-to-camera relationships. For example, the placement solution can be encouraged to have cameras that image the same important locations from different viewing directions, which can enable reconstruction and surveillance tasks to perform better. We show that the general camera placement problem can be formulated mathematically as a convex binary quadratic program (BQP) under linear constraints. Moreover, we propose an optimization strategy with a favorable trade-off between speed and solution quality. Our solution is almost as fast as a greedy treatment of the problem, but the quality is significantly higher, so much so that it is comparable to exact solutions that take orders of magnitude more computation time. Because it is computationally attractive, our method also allows users to explore the space of solutions for variations in input parameters. To evaluate its effectiveness, we show a range of 3D results on real-world floorplans (garage, hotel, mall, and airport). ​

  6. The eye of the camera: effects of security cameras on pro-social behavior

    NARCIS (Netherlands)

    van Rompay, T.J.L.; Vonk, D.J.; Fransen, M.L.

    2009-01-01

    This study addresses the effects of security cameras on prosocial behavior. Results from previous studies indicate that the presence of others can trigger helping behavior, arising from the need for approval of others. Extending these findings, the authors propose that security cameras can likewise

  7. A single camera photogrammetry system for multi-angle fast localization of EEG electrodes.

    Science.gov (United States)

    Qian, Shuo; Sheng, Yang

    2011-11-01

    Photogrammetry has become an effective method for the determination of electroencephalography (EEG) electrode positions in three dimensions (3D). Capturing multi-angle images of the electrodes on the head is a fundamental objective in the design of photogrammetry system for EEG localization. Methods in previous studies are all based on the use of either a rotating camera or multiple cameras, which are time-consuming or not cost-effective. This study aims to present a novel photogrammetry system that can realize simultaneous acquisition of multi-angle head images in a single camera position. Aligning two planar mirrors with the angle of 51.4°, seven views of the head with 25 electrodes are captured simultaneously by the digital camera placed in front of them. A complete set of algorithms for electrode recognition, matching, and 3D reconstruction is developed. It is found that the elapsed time of the whole localization procedure is about 3 min, and camera calibration computation takes about 1 min, after the measurement of calibration points. The positioning accuracy with the maximum error of 1.19 mm is acceptable. Experimental results demonstrate that the proposed system provides a fast and cost-effective method for the EEG positioning.

  8. Film cameras or digital sensors? The challenge ahead for aerial imaging

    Science.gov (United States)

    Light, D.L.

    1996-01-01

    Cartographic aerial cameras continue to play the key role in producing quality products for the aerial photography business, and specifically for the National Aerial Photography Program (NAPP). One NAPP photograph taken with cameras capable of 39 lp/mm system resolution can contain the equivalent of 432 million pixels at 11 ??m spot size, and the cost is less than $75 per photograph to scan and output the pixels on a magnetic storage medium. On the digital side, solid state charge coupled device linear and area arrays can yield quality resolution (7 to 12 ??m detector size) and a broader dynamic range. If linear arrays are to compete with film cameras, they will require precise attitude and positioning of the aircraft so that the lines of pixels can be unscrambled and put into a suitable homogeneous scene that is acceptable to an interpreter. Area arrays need to be much larger than currently available to image scenes competitive in size with film cameras. Analysis of the relative advantages and disadvantages of the two systems show that the analog approach is more economical at present. However, as arrays become larger, attitude sensors become more refined, global positioning system coordinate readouts become commonplace, and storage capacity becomes more affordable, the digital camera may emerge as the imaging system for the future. Several technical challenges must be overcome if digital sensors are to advance to where they can support mapping, charting, and geographic information system applications.

  9. Propellant Residues Deposition from Firing of 40-mm Grenades

    Science.gov (United States)

    2010-09-01

    sampling, the bag was labeled, a tag labeled and attached to the bag, the bag sealed with a tie-wrap, the sample recorded in a log book, and the...NG 1.5 11. 0.73% Leopard Tank2 105-mm (MIS) M1 DNT 300 6.7 2.2x10-3% 105-mm (Trays) M1 DNT 300 7.8 2.7x10-3% Howitzers 105-mm M1-I & II DNT 42

  10. Initial results from 50mm short SSC dipoles at Fermilab

    International Nuclear Information System (INIS)

    Bossert, R.C.; Brandt, J.S.; Carson, J.A.; Coulter, K.; Delchamps, S.; Ewald, K.D.; Fulton, H.; Gonczy, I.; Gourlay, S.A.; Jaffery, T.S.; Kinney, W.; Koska, W.; Lamm, M.J.; Strait, J.B.; Wake, M.; Gordon, M.; Hassan, N.; Sims, R.; Winters, M.

    1991-03-01

    Several short model SSC 50 mm bore dipoles are being built and tested at Fermilab. Mechanical design of these magnets has been determined from experience involved in the construction and testing of 40 mm dipoles. Construction experience includes coil winding, curing and measuring, coil end part design and fabrication, ground insulation, instrumentation, collaring and yoke assembly. Fabrication techniques are explained and construction problems are discussed. Similarities and differences from the 40 mm dipole tooling and management components are outlined. Test results from the first models are presented. 19 refs., 12 figs

  11. P 600/650 X-ray streak camera with optimized spatio-temporal resolution

    International Nuclear Information System (INIS)

    Boutry, B.; Cavailler, C.; Fleurot, N.

    1982-07-01

    This paper presents the latest performances of the P 600 X-ray streak camera designed for laser fusion experiments. It reaches very high performances in the 1.5 to 10 keV range: 16 to 20 pl.mm -1 for the maximum sweep speed which corresponds to a 2 ps theoretical time resolution. We discuss its adaptation to the soft X-ray spectral range down to 100 eV

  12. Acceptance/Operational Test Report for Tank 241-AN-104 camera and camera purge control system

    International Nuclear Information System (INIS)

    Castleberry, J.L.

    1995-11-01

    This Acceptance/Operational Test Procedure (ATP/OTP) will document the satisfactory operation of the camera purge panel, purge control panel, color camera system and associated control components destined for installation. The final acceptance of the complete system will be performed in the field. The purge panel and purge control panel will be tested for its safety interlock which shuts down the camera and pan-and-tilt inside the tank vapor space during loss of purge pressure and that the correct purge volume exchanges are performed as required by NFPA 496. This procedure is separated into seven sections. This Acceptance/Operational Test Report documents the successful acceptance and operability testing of the 241-AN-104 camera system and camera purge control system

  13. Effects of canal enlargement and irrigation needle depth on the cleaning of the root canal system at 3 mm from the apex

    Directory of Open Access Journals (Sweden)

    Ho-Jin Moon

    2012-02-01

    Full Text Available Objectives The aim of this study was to test the hypothesis, that the effectiveness of irrigation in removing smear layer in the apical third of root canal system is dependent on the depth of placement of the irrigation needle into the root canal and the enlargement size of the canal. Materials and Methods Eighty sound human lower incisors were divided into eight groups according to the enlargement size (#25, #30, #35 and #40 and the needle penetration depth (3 mm from working length, WL-3 mm and 9 mm from working length, WL-9 mm. Each canal was enlarged to working length with Profile.06 Rotary Ni-Ti files and irrigated with 5.25% NaOCl. Then, each canal received a final irrigation with 3 mL of 3% EDTA for 4 min, followed by 5 mL of 5.25% NaOCl at different level (WL-3 mm and WL-9 mm from working length. Each specimen was prepared for the scanning electron microscope (SEM. Photographs of the 3mm area from the apical constriction of each canal with a magnification of ×250, ×500, ×1,000, ×2,500 were taken for the final evaluation. Results Removal of smear layer in WL-3 mm group showed a significantly different effect when the canal was enlarged to larger than #30. There was a significant difference in removing apical smear layer between the needle penetration depth of WL-3 mm and WL-9 mm. Conclusions Removal of smear layer from the apical portion of root canals was effectively accomplished with apical instrumentation to #35/40 06 taper file and 3 mm needle penetration from the working length.

  14. STS-56 MS2 Cockrell with HERCULES camera at overhead window W8 on OV-103's FD

    Science.gov (United States)

    1993-01-01

    STS-56 Mission Specialist 2 (MS2) Kenneth D. Cockrell records Earth imagery with the Hand-held, Earth-oriented, Real-time, Cooperative, User-friendly, Location-targeting and Environmental System (HERCULES) 35mm camera. Cockrell is positioned under aft flight deck overhead window W8 with his back to the onorbit station controls and aft flight deck viewing window W10. HERCULES is a device that makes it simple for Shuttle crewmembers to take pictures of Earth, as they merely point a modified 35mm camera and shoot any interesting feature, whose latitude and longitude are automatically determined in real-time. The powder-box shaped attachment is the HERCULES inertial measurement unit (HIMU) with the Electronic Still Camera Electronic Box (ESCEB) underneath it. The STS-56 crew downlinked a number of the still images during the flight, while others are likely to be stored on disc and returned to Earth with the crew.

  15. Development of a Compton camera for medical applications based on silicon strip and scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Krimmer, J., E-mail: j.krimmer@ipnl.in2p3.fr [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Ley, J.-L. [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Abellan, C.; Cachemiche, J.-P. [Aix-Marseille Université, CNRS/IN2P3, CPPM UMR 7346, 13288 Marseille (France); Caponetto, L.; Chen, X.; Dahoumane, M.; Dauvergne, D. [Institut de Physique Nucléaire de Lyon, Université de Lyon, Université Lyon 1, CNRS/IN2P3 UMR 5822, 69622 Villeurbanne cedex (France); Freud, N. [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA - Lyon, Université Lyon 1, Centre Léon Bérard (France); Joly, B.; Lambert, D.; Lestand, L. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); Létang, J.M. [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA - Lyon, Université Lyon 1, Centre Léon Bérard (France); Magne, M. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, F-63000 Clermont-Ferrand (France); and others

    2015-07-01

    A Compton camera is being developed for the purpose of ion-range monitoring during hadrontherapy via the detection of prompt-gamma rays. The system consists of a scintillating fiber beam tagging hodoscope, a stack of double sided silicon strip detectors (90×90×2 mm{sup 3}, 2×64 strips) as scatter detectors, as well as bismuth germanate (BGO) scintillation detectors (38×35×30 mm{sup 3}, 100 blocks) as absorbers. The individual components will be described, together with the status of their characterization.

  16. A 3D high-resolution gamma camera for radiopharmaceutical studies with small animals

    CERN Document Server

    Loudos, G K; Giokaris, N D; Styliaris, E; Archimandritis, S C; Varvarigou, A D; Papanicolas, C N; Majewski, S; Weisenberger, D; Pani, R; Scopinaro, F; Uzunoglu, N K; Maintas, D; Stefanis, K

    2003-01-01

    The results of studies conducted with a small field of view tomographic gamma camera based on a Position Sensitive Photomultiplier Tube are reported. The system has been used for the evaluation of radiopharmaceuticals in small animals. Phantom studies have shown a spatial resolution of 2 mm in planar and 2-3 mm in tomographic imaging. Imaging studies in mice have been carried out both in 2D and 3D. Conventional radiopharmaceuticals have been used and the results have been compared with images from a clinically used system.

  17. Gate Simulation of a Gamma Camera

    International Nuclear Information System (INIS)

    Abidi, Sana; Mlaouhi, Zohra

    2008-01-01

    Medical imaging is a very important diagnostic because it allows for an exploration of the internal human body. The nuclear imaging is an imaging technique used in the nuclear medicine. It is to determine the distribution in the body of a radiotracers by detecting the radiation it emits using a detection device. Two methods are commonly used: Single Photon Emission Computed Tomography (SPECT) and the Positrons Emission Tomography (PET). In this work we are interested on modelling of a gamma camera. This simulation is based on Monte-Carlo language and in particular Gate simulator (Geant4 Application Tomographic Emission). We have simulated a clinical gamma camera called GAEDE (GKS-1) and then we validate these simulations by experiments. The purpose of this work is to monitor the performance of these gamma camera and the optimization of the detector performance and the the improvement of the images quality. (Author)

  18. Mechanical Design of the LSST Camera

    Energy Technology Data Exchange (ETDEWEB)

    Nordby, Martin; Bowden, Gordon; Foss, Mike; Guiffre, Gary; /SLAC; Ku, John; /Unlisted; Schindler, Rafe; /SLAC

    2008-06-13

    The LSST camera is a tightly packaged, hermetically-sealed system that is cantilevered into the main beam of the LSST telescope. It is comprised of three refractive lenses, on-board storage for five large filters, a high-precision shutter, and a cryostat that houses the 3.2 giga-pixel CCD focal plane along with its support electronics. The physically large optics and focal plane demand large structural elements to support them, but the overall size of the camera and its components must be minimized to reduce impact on the image stability. Also, focal plane and optics motions must be minimized to reduce systematic errors in image reconstruction. Design and analysis for the camera body and cryostat will be detailed.

  19. Collimated trans-axial tomographic scintillation camera

    International Nuclear Information System (INIS)

    1980-01-01

    The objects of this invention are first to reduce the time required to obtain statistically significant data in trans-axial tomographic radioisotope scanning using a scintillation camera. Secondly, to provide a scintillation camera system to increase the rate of acceptance of radioactive events to contribute to the positional information obtainable from a known radiation source without sacrificing spatial resolution. Thirdly to reduce the scanning time without loss of image clarity. The system described comprises a scintillation camera detector, means for moving this in orbit about a cranial-caudal axis relative to a patient and a collimator having septa defining apertures such that gamma rays perpendicular to the axis are admitted with high spatial resolution, parallel to the axis with low resolution. The septa may be made of strips of lead. Detailed descriptions are given. (U.K.)

  20. PEOPLE REIDENTIFCATION IN A DISTRIBUTED CAMERA NETWORK

    Directory of Open Access Journals (Sweden)

    Icaro Oliveira de Oliveira

    2010-06-01

    Full Text Available This paper presents an approach to the object reidentification problem in a distributed camera network system. The reidentification or reacquisition problem consists essentially on the matching process of images acquired from different cameras. This work is applied in a monitored environment by cameras. This application is important to modern security systems, in which the targets presence identification in the environment expands the capacity of action by security agents in real time and provides important parameters like localization for each target. We used target’s interest points and target’s color with features for reidentification. The satisfactory results were obtained from real experiments in public video datasets and synthetic images with noise.

  1. Progress in Long Scale Length Laser-Plasma Interactions

    International Nuclear Information System (INIS)

    Glenzer, S H; Arnold, P; Bardsley, G; Berger, R L; Bonanno, G; Borger, T; Bower, D E; Bowers, M; Bryant, R; Buckman, S.; Burkhart, S C; Campbell, K; Chrisp, M P; Cohen, B I; Constantin, G; Cooper, F; Cox, J; Dewald, E; Divol, L; Dixit, S; Duncan, J; Eder, D; Edwards, J; Erbert, G; Felker, B; Fornes, J; Frieders, G; Froula, D H; Gardner, S D; Gates, C; Gonzalez, M; Grace, S; Gregori, G; Greenwood, A; Griffith, R; Hall, T; Hammel, B A; Haynam, C; Heestand, G; Henesian, M; Hermes, G; Hinkel, D; Holder, J; Holdner, F; Holtmeier, G; Hsing, W; Huber, S; James, T; Johnson, S; Jones, O S; Kalantar, D; Kamperschroer, J H; Kauffman, R; Kelleher, T; Knight, J; Kirkwood, R K; Kruer, W L; Labiak, W; Landen, O L; Langdon, A B; Langer, S; Latray, D; Lee, A; Lee, F D; Lund, D; MacGowan, B; Marshall, S; McBride, J; McCarville, T; McGrew, L; Mackinnon, A J; Mahavandi, S; Manes, K; Marshall, C; Mertens, E; Meezan, N; Miller, G; Montelongo, S; Moody, J D; Moses, E; Munro, D; Murray, J; Neumann, J; Newton, M; Ng, E; Niemann, C; Nikitin, A; Opsahl, P; Padilla, E; Parham, T; Parrish, G; Petty, C; Polk, M; Powell, C; Reinbachs, I; Rekow, V; Rinnert, R; Riordan, B; Rhodes, M.

    2003-01-01

    The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 mm and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3ω) with a total intensity of 2 x 10 15 W cm -2 . The targets were filled with 1 atm of CO 2 producing of up to 7 mm long homogeneously heated plasmas with densities of n e = 6 x 10 20 cm -3 and temperatures of T e = 2 keV. The high energy in a NIF quad of beams of 16kJ, illuminating the target from one direction, creates unique conditions for the study of laser plasma interactions at scale lengths not previously accessible. The propagation through the large-scale plasma was measured with a gated x-ray imager that was filtered for 3.5 keV x rays. These data indicate that the beams interact with the full length of this ignition-scale plasma during the last ∼1 ns of the experiment. During that time, the full aperture measurements of the stimulated Brillouin scattering and stimulated Raman scattering show scattering into the four focusing lenses of 6% for the smallest length (∼2 mm). increasing to 12% for ∼7 mm. These results demonstrate the NIF experimental capabilities and further provide a benchmark for three-dimensional modeling of the laser-plasma interactions at ignition-size scale lengths

  2. 7 Length-weight relationship

    African Journals Online (AJOL)

    Administrator

    Length-weight measurements were taken from well-preserved fish specimens from which stomachs were extracted for the analysis of the food contents, using frequency of occurrence, numerical and gravimetric methods, as well as index of relative importance. The length-frequency analysis showed a size distribution with a ...

  3. Comparison of fiber length analyzers

    Science.gov (United States)

    Don Guay; Nancy Ross Sutherland; Walter Rantanen; Nicole Malandri; Aimee Stephens; Kathleen Mattingly; Matt Schneider

    2005-01-01

    In recent years, several fiber new fiber length analyzers have been developed and brought to market. The new instruments provide faster measurements and the capability of both laboratory and on-line analysis. Do the various fiber analyzers provide the same length, coarseness, width, and fines measurements for a given fiber sample? This paper provides a comparison of...

  4. Small Orbital Stereo Tracking Camera Technology Development

    Science.gov (United States)

    Gagliano, L.; Bryan, T.; MacLeod, T.

    On-Orbit Small Debris Tracking and Characterization is a technical gap in the current National Space Situational Awareness necessary to safeguard orbital assets and crew. This poses a major risk of MOD damage to ISS and Exploration vehicles. In 2015 this technology was added to NASAs Office of Chief Technologist roadmap. For missions flying in or assembled in or staging from LEO, the physical threat to vehicle and crew is needed in order to properly design the proper level of MOD impact shielding and proper mission design restrictions. Need to verify debris flux and size population versus ground RADAR tracking. Use of ISS for In-Situ Orbital Debris Tracking development provides attitude, power, data and orbital access without a dedicated spacecraft or restricted operations on-board a host vehicle as a secondary payload. Sensor Applicable to in-situ measuring orbital debris in flux and population in other orbits or on other vehicles. Could enhance safety on and around ISS. Some technologies extensible to monitoring of extraterrestrial debris as well To help accomplish this, new technologies must be developed quickly. The Small Orbital Stereo Tracking Camera is one such up and coming technology. It consists of flying a pair of intensified megapixel telephoto cameras to evaluate Orbital Debris (OD) monitoring in proximity of International Space Station. It will demonstrate on-orbit optical tracking (in situ) of various sized objects versus ground RADAR tracking and small OD models. The cameras are based on Flight Proven Advanced Video Guidance Sensor pixel to spot algorithms (Orbital Express) and military targeting cameras. And by using twin cameras we can provide Stereo images for ranging & mission redundancy. When pointed into the orbital velocity vector (RAM), objects approaching or near the stereo camera set can be differentiated from the stars moving upward in background.

  5. Phase camera experiment for Advanced Virgo

    International Nuclear Information System (INIS)

    Agatsuma, Kazuhiro; Beuzekom, Martin van; Schaaf, Laura van der; Brand, Jo van den

    2016-01-01

    We report on a study of the phase camera, which is a frequency selective wave-front sensor of a laser beam. This sensor is utilized for monitoring sidebands produced by phase modulations in a gravitational wave (GW) detector. Regarding the operation of the GW detectors, the laser modulation/demodulation method is used to measure mirror displacements and used for the position controls. This plays a significant role because the quality of controls affect the noise level of the GW detector. The phase camera is able to monitor each sideband separately, which has a great benefit for the manipulation of the delicate controls. Also, overcoming mirror aberrations will be an essential part of Advanced Virgo (AdV), which is a GW detector close to Pisa. Especially low-frequency sidebands can be affected greatly by aberrations in one of the interferometer cavities. The phase cameras allow tracking such changes because the state of the sidebands gives information on mirror aberrations. A prototype of the phase camera has been developed and is currently tested. The performance checks are almost completed and the installation of the optics at the AdV site has started. After the installation and commissioning, the phase camera will be combined to a thermal compensation system that consists of CO 2 lasers and compensation plates. In this paper, we focus on the prototype and show some limitations from the scanner performance. - Highlights: • The phase camera is being developed for a gravitational wave detector. • A scanner performance limits the operation speed and layout design of the system. • An operation range was found by measuring the frequency response of the scanner.

  6. A machine vision system with CCD cameras for patient positioning in radiotherapy: a preliminary report.

    Science.gov (United States)

    Yoshitake, Tadamasa; Nakamura, Katsumasa; Shioyama, Yoshiyuki; Sasaki, Tomonari; Ohga, Saiji; Yamaguchi, Toshihiro; Toba, Takashi; Anai, Shigeo; Terashima, Hiromi; Honda, Hiroshi

    2005-12-01

    To determine positioning accuracy of a machine vision system in radiotherapy. The machine vision system was composed of 640 x 480 pixel CCD cameras and computerized control systems. For image acquisition, the phantom was set up for the reference position and a single CCD camera was positioned 1.5 m from the isocenter. The image data of the fiducial marker with 1.5 mm lead pellet on the lateral surface of the phantom was captured onto the CCD, and then the position of the marker was accurately calculated. The phantom was moved 0.25, 0.50, 0.75, 1.00, 2.00, and 3.00 mm from the reference position, using a micrometer head. The position of the fiducial marker was analyzed using a kilo-voltage fluoroscopic imaging system and a machine vision system. Using fluoroscopic images, the discrepancy between the actual movement of the phantom by micrometer heads and the measurement was found to be 0.12 +/- 0.05 mm (mean +/- standard deviation). In contrast, the detection of the movement by the machine vision system coincided with the discrepancy of 0.0067 +/- 0.0048 mm. This study suggests that the machine vision system can be used to measure small changes in patient position with a resolution of less than 0.1 mm.

  7. Proportional chamber with 1 mm spacing of the signal wires

    International Nuclear Information System (INIS)

    Balandin, V.P.; Veresh, I.; Gus'kov, B.N.

    1988-01-01

    The construction of a three-coordinate proportional chamber with a 256 x 256 mm working region and with 1.0 and 2.0 mm spacing of the signal wires is described and its characteristics are presented. A charged-particle recording efficiency of 99% was achieved with the gas mixture Ar + 20% C 4 H 10 + 2% C 3 H 8 O 2 + 0.3% CF 3 Br. The plateau on the efficiency curve equaled 750 and greater than 1000 V and the spatial resolution equaled 0.318 and 0.67 mm for planes with spacings of 1 and 2 mm respectively. The effect of proportional chambers on the accuracy with which the coordinates of the vertices of the multitrack events were determined with a BIS-2 spectrometer was studied

  8. Feasibility study of a lens-coupled charge-coupled device gamma camera

    International Nuclear Information System (INIS)

    Lee, Hakjae; Jung, Youngjun; Kim, Jungmin; Bae, Seungbin; Lee, Kisung; Kang, Jungwon

    2011-01-01

    A charge-coupled device (CCD) is generally used in a digital camera as a light-collecting device such as a photomultiplier tube (PMT). Because of its low sensitivity and very high dark current, CCD have not been popularly used for gamma imaging systems. However, a recent CCD technological breakthrough has improved CCD sensitivity, and the use of a Peltier cooling system can significantly minimize the dark current. In this study, we investigated the feasibility of a prototype CCD gamma camera consisting of a CsI scintillator, optical lenses, and a CCD module. Despite electron-multiplying (EM) CCDs having higher performance, in this study, we built a cost-effective system consisted of low-cost components compared to EMCCDs. Our prototype detector consists of a CsI scintillator, two optical lenses, and a conventional Peltier-cooled CCD. The performance of this detector was evaluated by acquiring the sensitivity, resolution, and the modulation transfer function (MTF). The sensitivity of the prototype detector showed excellent linearity. With a 1 mm-diameter pinhole collimator, the full width at half-maximum (FWHM) of a 1.1 mm Tc-99m line source image was 2.85 mm. These results show that the developed prototype camera is feasible for small animal gamma imaging.

  9. Performances evaluation of the coincidence detection on a gamma-camera

    International Nuclear Information System (INIS)

    Dreuille, O. de; Gaillard, J.F.; Brasse, D.; Bendriem, B.; Groiselle, C.; Rocchisani, J.M.; Moretti, J.L.

    2000-01-01

    The performance of the VERTEX gamma-camera (ADAC) working in coincidence mode are investigated using a protocol derived from the NEMA and IEC recommendations. With a field of view determined by two rectangular detectors (50.8 cm x 40 cm) composed of NaI crystal, this camera allows a 3-D acquisition with different energy window configurations: photopeak-photopeak only (PP) and photopeak-photopeak + photopeak-Compton (PC). An energy resolution of 11% and a scatter fraction of 27% and 33% for the 3D-PP and 3D-PC mode respectively are the main significant results of our study. The spatial resolution equals 5.9 mm and the limit of the detectability ranges from 16 mm to 13 mm for a contrast of 2.5: as a function of the random estimation, the maximum of the Noise Equivalent Count rate varies from 3 kcps to 4.5 kcps for the PP mode and from 3.85 kcps to 6.1 kcps for the PC mode. These maxima are reached for a concentration of 8 kBq/ml for the PP mode and 5 kBq/ml for the PC mode. These values are compared with the results obtained by other groups for the VERTEX gamma camera and several dedicated PET systems. (authors)

  10. SU-F-J-140: Using Handheld Stereo Depth Cameras to Extend Medical Imaging for Radiation Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, C; Xing, L; Yu, S [Stanford University, Stanford, CA (United States)

    2016-06-15

    Purpose: A correct body contour is essential for the accuracy of dose calculation in radiation therapy. While modern medical imaging technologies provide highly accurate representations of body contours, there are times when a patient’s anatomy cannot be fully captured or there is a lack of easy access to CT/MRI scanning. Recently, handheld cameras have emerged that are capable of performing three dimensional (3D) scans of patient surface anatomy. By combining 3D camera and medical imaging data, the patient’s surface contour can be fully captured. Methods: A proof-of-concept system matches a patient surface model, created using a handheld stereo depth camera (DC), to the available areas of a body contour segmented from a CT scan. The matched surface contour is then converted to a DICOM structure and added to the CT dataset to provide additional contour information. In order to evaluate the system, a 3D model of a patient was created by segmenting the body contour with a treatment planning system (TPS) and fabricated with a 3D printer. A DC and associated software were used to create a 3D scan of the printed phantom. The surface created by the camera was then registered to a CT model that had been cropped to simulate missing scan data. The aligned surface was then imported into the TPS and compared with the originally segmented contour. Results: The RMS error for the alignment between the camera and cropped CT models was 2.26 mm. Mean distance between the aligned camera surface and ground truth model was −1.23 +/−2.47 mm. Maximum deviations were < 1 cm and occurred in areas of high concavity or where anatomy was close to the couch. Conclusion: The proof-of-concept study shows an accurate, easy and affordable method to extend medical imaging for radiation therapy planning using 3D cameras without additional radiation. Intel provided the camera hardware used in this study.

  11. Results with the UKIRT infrared camera

    International Nuclear Information System (INIS)

    Mclean, I.S.

    1987-01-01

    Recent advances in focal plane array technology have made an immense impact on infrared astronomy. Results from the commissioning of the first infrared camera on UKIRT (the world's largest IR telescope) are presented. The camera, called IRCAM 1, employs the 62 x 58 InSb DRO array from SBRC in an otherwise general purpose system which is briefly described. Several imaging modes are possible including staring, chopping and a high-speed snapshot mode. Results to be presented include the first true high resolution images at IR wavelengths of the entire Orion nebula

  12. Camera-enabled techniques for organic synthesis

    Directory of Open Access Journals (Sweden)

    Steven V. Ley

    2013-05-01

    Full Text Available A great deal of time is spent within synthetic chemistry laboratories on non-value-adding activities such as sample preparation and work-up operations, and labour intensive activities such as extended periods of continued data collection. Using digital cameras connected to computer vision algorithms, camera-enabled apparatus can perform some of these processes in an automated fashion, allowing skilled chemists to spend their time more productively. In this review we describe recent advances in this field of chemical synthesis and discuss how they will lead to advanced synthesis laboratories of the future.

  13. Nonmedical applications of a positron camera

    International Nuclear Information System (INIS)

    Hawkesworth, M.R.; Parker, D.J.; Fowles, P.; Crilly, J.F.; Jefferies, N.L.; Jonkers, G.

    1991-01-01

    The positron camera in the School on Physics and Space Research, University of Birmingham, is based on position-sensitive multiwire γ-ray detectors developed at the Rutherford Appleton Laboratory. The current characteristics of the camera are discussed with particular reference to its suitability for flow mapping in industrial subjects. The techniques developed for studying the dynamics of processes with time scales ranging from milliseconds to days are described, and examples of recent results from a variety of industrial applications are presented. (orig.)

  14. QM/MM free energy simulations: recent progress and challenges

    Science.gov (United States)

    Lu, Xiya; Fang, Dong; Ito, Shingo; Okamoto, Yuko; Ovchinnikov, Victor

    2016-01-01

    Due to the higher computational cost relative to pure molecular mechanical (MM) simulations, hybrid quantum mechanical/molecular mechanical (QM/MM) free energy simulations particularly require a careful consideration of balancing computational cost and accuracy. Here we review several recent developments in free energy methods most relevant to QM/MM simulations and discuss several topics motivated by these developments using simple but informative examples that involve processes in water. For chemical reactions, we highlight the value of invoking enhanced sampling technique (e.g., replica-exchange) in umbrella sampling calculations and the value of including collective environmental variables (e.g., hydration level) in metadynamics simulations; we also illustrate the sensitivity of string calculations, especially free energy along the path, to various parameters in the computation. Alchemical free energy simulations with a specific thermodynamic cycle are used to probe the effect of including the first solvation shell into the QM region when computing solvation free energies. For cases where high-level QM/MM potential functions are needed, we analyze two different approaches: the QM/MM-MFEP method of Yang and co-workers and perturbative correction to low-level QM/MM free energy results. For the examples analyzed here, both approaches seem productive although care needs to be exercised when analyzing the perturbative corrections. PMID:27563170

  15. Thermal regulation of tightly packed solid-state photodetectors in a 1 mm{sup 3} resolution clinical PET system

    Energy Technology Data Exchange (ETDEWEB)

    Freese, D. L.; Vandenbroucke, A.; Innes, D.; Lau, F. W. Y.; Hsu, D. F. C.; Reynolds, P. D.; Levin, Craig S., E-mail: cslevin@stanford.edu [Departments of Electrical Engineering, Radiology, Physics, and BioEngineering, Stanford University, Stanford, California 94305-5128 (United States)

    2015-01-15

    Purpose: Silicon photodetectors are of significant interest for use in positron emission tomography (PET) systems due to their compact size, insensitivity to magnetic fields, and high quantum efficiency. However, one of their main disadvantages is fluctuations in temperature cause strong shifts in gain of the devices. PET system designs with high photodetector density suffer both increased thermal density and constrained options for thermally regulating the devices. This paper proposes a method of thermally regulating densely packed silicon photodetectors in the context of a 1 mm{sup 3} resolution, high-sensitivity PET camera dedicated to breast imaging. Methods: The PET camera under construction consists of 2304 units, each containing two 8 × 8 arrays of 1 mm{sup 3} LYSO crystals coupled to two position sensitive avalanche photodiodes (PSAPD). A subsection of the proposed camera with 512 PSAPDs has been constructed. The proposed thermal regulation design uses water-cooled heat sinks, thermoelectric elements, and thermistors to measure and regulate the temperature of the PSAPDs in a novel manner. Active cooling elements, placed at the edge of the detector stack due to limited access, are controlled based on collective leakage current and temperature measurements in order to keep all the PSAPDs at a consistent temperature. This thermal regulation design is characterized for the temperature profile across the camera and for the time required for cooling changes to propagate across the camera. These properties guide the implementation of a software-based, cascaded proportional-integral-derivative control loop that controls the current through the Peltier elements by monitoring thermistor temperature and leakage current. The stability of leakage current, temperature within the system using this control loop is tested over a period of 14 h. The energy resolution is then measured over a period of 8.66 h. Finally, the consistency of PSAPD gain between independent

  16. Thermal regulation of tightly packed solid-state photodetectors in a 1 mm(3) resolution clinical PET system.

    Science.gov (United States)

    Freese, D L; Vandenbroucke, A; Innes, D; Lau, F W Y; Hsu, D F C; Reynolds, P D; Levin, Craig S

    2015-01-01

    Silicon photodetectors are of significant interest for use in positron emission tomography (PET) systems due to their compact size, insensitivity to magnetic fields, and high quantum efficiency. However, one of their main disadvantages is fluctuations in temperature cause strong shifts in gain of the devices. PET system designs with high photodetector density suffer both increased thermal density and constrained options for thermally regulating the devices. This paper proposes a method of thermally regulating densely packed silicon photodetectors in the context of a 1 mm(3) resolution, high-sensitivity PET camera dedicated to breast imaging. The PET camera under construction consists of 2304 units, each containing two 8 × 8 arrays of 1 mm(3) LYSO crystals coupled to two position sensitive avalanche photodiodes (PSAPD). A subsection of the proposed camera with 512 PSAPDs has been constructed. The proposed thermal regulation design uses water-cooled heat sinks, thermoelectric elements, and thermistors to measure and regulate the temperature of the PSAPDs in a novel manner. Active cooling elements, placed at the edge of the detector stack due to limited access, are controlled based on collective leakage current and temperature measurements in order to keep all the PSAPDs at a consistent temperature. This thermal regulation design is characterized for the temperature profile across the camera and for the time required for cooling changes to propagate across the camera. These properties guide the implementation of a software-based, cascaded proportional-integral-derivative control loop that controls the current through the Peltier elements by monitoring thermistor temperature and leakage current. The stability of leakage current, temperature within the system using this control loop is tested over a period of 14 h. The energy resolution is then measured over a period of 8.66 h. Finally, the consistency of PSAPD gain between independent operations of the camera over 10

  17. Ultra-Compact Multitip Scanning Probe Microscope with an Outer Diameter of 50 mm

    Science.gov (United States)

    Cherepanov, Vasily; Zubkov, Evgeny; Junker, Hubertus; Korte, Stefan; Blab, Marcus; Coenen, Peter; Voigtländer, Bert

    We present a multitip scanning tunneling microscope (STM) where four independent STM units are integrated on a diameter of 50 mm. The coarse positioning of the tips is done under the control of an optical microscope or an SEM in vacuum. The heart of this STM is a new type of piezoelectric coarse approach called Koala Drive which can have a diameter greater than 2.5 mm and a length smaller than 10 mm. Alternating movements of springs move a central tube which holds the STM tip or AFM sensor. This new operating principle provides a smooth travel sequence and avoids shaking which is intrinsically present for nanopositioners based on inertial motion with saw tooth driving signals. Inserting the Koala Drive in a piezo tube for xyz-scanning integrates a complete STM inside a 4 mm outer diameter piezo tube of Koala Drive makes the scanning probe microscopy design ultra-compact and accordingly leads to a high mechanical stability. The drive is UHV, low temperature, and magnetic field compatible. The compactness of the Koala Drive allows building a four-tip STM as small as a single-tip STM with a drift of Koala Drive.

  18. Monte Carlo simulation for dual head gamma camera

    International Nuclear Information System (INIS)

    Osman, Yousif Bashir Soliman

    2015-12-01

    Monte Carlo (MC) simulation technique was used widely in medical physics applications. In nuclear medicine MC was used to design new medical imaging devices such as positron emission tomography (PET), gamma camera and single photon emission computed tomography (SPECT). Also it can be used to study the factors affecting image quality and internal dosimetry, Gate is on of monte Carlo code that has a number of advantages for simulation of SPECT and PET. There is a limit accessibilities in machines which are used in clinics because of the work load of machines. This makes it hard to evaluate some factors effecting machine performance which must be evaluated routinely. Also because of difficulties of carrying out scientific research and training of students, MC model can be optimum solution for the problem. The aim of this study was to use gate monte Carlo code to model Nucline spirit, medico dual head gamma camera hosted in radiation and isotopes center of Khartoum which is equipped with low energy general purpose LEGP collimators. This was used model to evaluate spatial resolution and sensitivity which is important factor affecting image quality and to demonstrate the validity of gate by comparing experimental results with simulation results on spatial resolution. The gate model of Nuclide spirit, medico dual head gamma camera was developed by applying manufacturer specifications. Then simulation was run. In evaluation of spatial resolution the FWHM was calculated from image profile of line source of Tc 99m gammas emitter of energy 140 KeV at different distances from modeled camera head at 5,10,15,20,22,27,32,37 cm and for these distances the spatial resolution was founded to be 5.76, 7.73, 10.7, 13.8, 14.01,16.91, 19.75 and 21.9 mm, respectively. These results showed a decrement of spatial resolution with increase of the distance between object (line source) and collimator in linear manner. FWHM calculated at 10 cm was compared with experimental results. The

  19. Three-layer GSO depth-of-interaction detector for high-energy gamma camera

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, S., E-mail: s-yama@met.nagoya-u.ac.jp [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya 461-8673 (Japan); Watabe, H. [Department of Molecular Imaging, Osaka University Graduate School of Medicine, Osaka (Japan); Kawachi, N.; Fujimaki, S. [Radiotracer Imaging Group, Japan Atomic Energy Agency, Takasaki (Japan); Kato, K. [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, 1-1-20 Daiko-Minami, Higashi-ku, Nagoya 461-8673 (Japan); Hatazawa, J. [Department of Molecular Imaging, Osaka University Graduate School of Medicine, Osaka (Japan); Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka (Japan)

    2014-04-11

    Using Ce-doped Gd{sub 2}SiO{sub 5} (GSO) of different Ce concentrations, three-layer DOI block detectors were developed to reduce the parallax error at the edges of a pinhole gamma camera for high-energy gamma photons. GSOs with Ce concentrations of 1.5 mol% (decay time ∼40 ns), 0.5 mol% crystal (∼60 ns), 0.4 mol% (∼80 ns) were selected for the depth of interaction (DOI) detectors. These three types of GSOs were optically coupled in the depth direction, arranged in a 22×22 matrix and coupled to a flat panel photomultiplier tube (FP-PMT, Hamamatsu H8500). Sizes of these GSO cells were 1.9 mm×1.9 mm×4 mm, 1.9 mm×1.9 mm×5 mm, and 1.9 mm×1.9 mm×6 mm for 1.5 mol%, 0.5 mol%, and 0.4 mol%, respectively. With these combinations of GSOs, all spots corresponding to GSO cells were clearly resolved in the position histogram. Pulse shape spectra showed three peaks for these three decay times of GSOs. The block detector was contained in a 2-cm-thick tungsten shield, and a pinhole collimator with a 0.5-mm aperture was mounted. With pulse shape discrimination, we separated the point source images of the Cs-137 for each DOI layer. The point source image of the lower layer was detected at the most central part of the field-of-view, and the distribution was the smallest. The point source image of the higher layer was detected at the most peripheral part of the field-of-view, and the distribution was widest. With this information, the spatial resolution of the pinhole gamma camera can be improved. We conclude that DOI detection is effective for pinhole gamma cameras for high energy gamma photons.

  20. The M/M/1 queue with inventory, lost sale and general lead times

    DEFF Research Database (Denmark)

    Saffari, Mohammad; Asmussen, Søren; Haji, Rasoul

    We consider an M/M/1 queueing system with inventory under the (r,Q) policy and with lost sales, in which demands occur according to a Poisson process and service times are exponentially distributed. All arriving customers during stockout are lost. We derive the stationary distributions of the joint...... queue length (number of customers in the system) and on-hand inventory when lead times are random variables and can take various distributions. The derived stationary distributions are used to formulate long-run average performance measures and cost functions in some numerical examples....

  1. Compact Optical Technique for Streak Camera Calibration

    International Nuclear Information System (INIS)

    Bell, P; Griffith, R; Hagans, K; Lerche, R; Allen, C; Davies, T; Janson, F; Justin, R; Marshall, B; Sweningsen, O

    2004-01-01

    The National Ignition Facility (NIF) is under construction at the Lawrence Livermore National Laboratory (LLNL) for the U.S. Department of Energy Stockpile Stewardship Program. Optical streak cameras are an integral part of the experimental diagnostics instrumentation. To accurately reduce data from the streak cameras a temporal calibration is required. This article describes a technique for generating trains of precisely timed short-duration optical pulses1 (optical comb generators) that are suitable for temporal calibrations. These optical comb generators (Figure 1) are used with the LLNL optical streak cameras. They are small, portable light sources that produce a series of temporally short, uniformly spaced, optical pulses. Comb generators have been produced with 0.1, 0.5, 1, 3, 6, and 10-GHz pulse trains of 780-nm wavelength light with individual pulse durations of ∼25-ps FWHM. Signal output is via a fiber-optic connector. Signal is transported from comb generator to streak camera through multi-mode, graded-index optical fibers. At the NIF, ultra-fast streak-cameras are used by the Laser Fusion Program experimentalists to record fast transient optical signals. Their temporal resolution is unmatched by any other transient recorder. Their ability to spatially discriminate an image along the input slit allows them to function as a one-dimensional image recorder, time-resolved spectrometer, or multichannel transient recorder. Depending on the choice of photocathode, they can be made sensitive to photon energies from 1.1 eV to 30 keV and beyond. Comb generators perform two important functions for LLNL streak-camera users. First, comb generators are used as a precision time-mark generator for calibrating streak camera sweep rates. Accuracy is achieved by averaging many streak camera images of comb generator signals. Time-base calibrations with portable comb generators are easily done in both the calibration laboratory and in situ. Second, comb signals are applied

  2. Evaluation of mobile phone camera benchmarking using objective camera speed and image quality metrics

    Science.gov (United States)

    Peltoketo, Veli-Tapani

    2014-11-01

    When a mobile phone camera is tested and benchmarked, the significance of image quality metrics is widely acknowledged. There are also existing methods to evaluate the camera speed. However, the speed or rapidity metrics of the mobile phone's camera system has not been used with the quality metrics even if the camera speed has become a more and more important camera performance feature. There are several tasks in this work. First, the most important image quality and speed-related metrics of a mobile phone's camera system are collected from the standards and papers and, also, novel speed metrics are identified. Second, combinations of the quality and speed metrics are validated using mobile phones on the market. The measurements are done toward application programming interface of different operating systems. Finally, the results are evaluated and conclusions are made. The paper defines a solution to combine different image quality and speed metrics to a single benchmarking score. A proposal of the combined benchmarking metric is evaluated using measurements of 25 mobile phone cameras on the market. The paper is a continuation of a previous benchmarking work expanded with visual noise measurement and updates of the latest mobile phone versions.

  3. Design of optical system for binocular fundus camera.

    Science.gov (United States)

    Wu, Jun; Lou, Shiliang; Xiao, Zhitao; Geng, Lei; Zhang, Fang; Wang, Wen; Liu, Mengjia

    2017-12-01

    A non-mydriasis optical system for binocular fundus camera has been designed in this paper. It can capture two images of the same fundus retinal region from different angles at the same time, and can be used to achieve three-dimensional reconstruction of fundus. It is composed of imaging system and illumination system. In imaging system, Gullstrand Le Grand eye model is used to simulate normal human eye, and Schematic eye model is used to test the influence of ametropia in human eye on imaging quality. Annular aperture and black dot board are added into illumination system, so that the illumination system can eliminate stray light produced by corneal-reflected light and omentoscopic lens. Simulation results show that MTF of each visual field at the cut-off frequency of 90lp/mm is greater than 0.2, system distortion value is -2.7%, field curvature is less than 0.1 mm, radius of Airy disc is 3.25um. This system has a strong ability of chromatic aberration correction and focusing, and can image clearly for human fundus in which the range of diopters is from -10 D to +6 D(1 D = 1 m -1 ).

  4. Inconsistency in 9 mm bullets: correlation of jacket thickness to post-impact geometry measured with non-destructive X-ray computed tomography.

    Science.gov (United States)

    Thornby, John; Landheer, Dirk; Williams, Tim; Barnes-Warden, Jane; Fenne, Paul; Norman, Danielle G; Attridge, Alex; Williams, Mark A

    2014-01-01

    Fundamental to any ballistic armour standard is the reference projectile to be defeated. Typically, for certification purposes, a consistent and symmetrical bullet geometry is assumed, however variations in bullet jacket dimensions can have far reaching consequences. Traditionally, characteristics and internal dimensions have been analysed by physically sectioning bullets--an approach which is of restricted scope and which precludes subsequent ballistic assessment. The use of a non-destructive X-ray computed tomography (CT) method has been demonstrated and validated (Kumar et al., 2011 [15]); the authors now apply this technique to correlate bullet impact response with jacket thickness variations. A set of 20 bullets (9 mm DM11) were selected for comparison and an image-based analysis method was employed to map jacket thickness and determine the centre of gravity of each specimen. Both intra- and inter-bullet variations were investigated, with thickness variations of the order of 200 μm commonly found along the length of all bullets and angular variations of up to 50 μm in some. The bullets were subsequently impacted against a rigid flat plate under controlled conditions (observed on a high-speed video camera) and the resulting deformed projectiles were re-analysed. The results of the experiments demonstrate a marked difference in ballistic performance between bullets from different manufacturers and an asymmetric thinning of the jacket is observed in regions of pre-impact weakness. The conclusions are relevant for future soft armour standards and provide important quantitative data for numerical model correlation and development. The implications of the findings of the work on the reliability and repeatability of the industry standard V50 ballistic test are also discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  5. The reliability of transabdominal cervical length measurement in a low-risk obstetric population: Comparison with transvaginal measurement.

    Science.gov (United States)

    Peng, Cheng-Ran; Chen, Chie-Pein; Wang, Kuo-Gon; Wang, Liang-Kai; Chen, Chen-Yu; Chen, Yi-Yung

    2015-04-01

    To determine the correlation between transabdominal (TA) and transvaginal (TV) cervical length measurement in a low-risk obstetric population in Taiwan. Women with a singleton pregnancy between 20 weeks and 24 weeks of gestation underwent postvoid TA and TV cervical length measurements. Differences between the measurements obtained using the two methods were evaluated. Two hundred and five women agreed to participate in the study. Paired TA and TV measurements were obtained in 174 women. The mean TA cervical length was 36.0 ± 4.9 mm and the mean TV cervical length was 37.6 ± 5.4 mm. The mean TA cervical length was shorter than the mean TV cervical length by 1.6 mm. The 5(th) percentile of TA and TV cervical length was 29 mm and 29.1 mm, respectively. The discrepancies between the two methods were not significantly correlated with maternal body mass index (BMI). All women with TV cervical length women in the present study, and the TA cervical length was closely correlated with the TV cervical length. The use of TA ultrasound could be an effective initial tool for cervical length screening in low-risk pregnant women. TA cervical length TV ultrasound. Copyright © 2015. Published by Elsevier B.V.

  6. The LLL compact 10-ps streak camera

    International Nuclear Information System (INIS)

    Thomas, S.W.; Houghton, J.W.; Tripp, G.R.; Coleman, L.W.

    1975-01-01

    The 10-ps streak camera has been redesigned to simplify its operation, reduce manufacturing costs, and improve its appearance. The electronics have been simplified, a film indexer added, and a contacted slit has been evaluated. Data support a 10-ps resolution. (author)

  7. Terrain mapping camera for Chandrayaan-1

    Indian Academy of Sciences (India)

    The Terrain Mapping Camera (TMC) on India's first satellite for lunar exploration, Chandrayaan-1, is for generating high-resolution 3-dimensional maps of the Moon. With this instrument, a complete topographic map of the Moon with 5 m spatial resolution and 10-bit quantization will be available for scientific studies.

  8. Thermoplastic film camera for holographic recording

    International Nuclear Information System (INIS)

    Liegeois, C.; Meyrueis, P.

    1982-01-01

    The design thermoplastic-film recording camera and its performance for holography of extended objects are reported. Special corona geometry and accurate control of development heat by constant current heating and high resolution measurement of the develop temperature make easy recording of reproducible, large aperture holograms possible. The experimental results give the transfer characteristics, the diffraction efficiency characteristics and the spatial frequency response. (orig.)

  9. A multidetector scintillation camera with 254 channels

    DEFF Research Database (Denmark)

    Sveinsdottir, E; Larsen, B; Rommer, P

    1977-01-01

    A computer-based scintillation camera has been designed for both dynamic and static radionuclide studies. The detecting head has 254 independent sodium iodide crystals, each with a photomultiplier and amplifier. In dynamic measurements simultaneous events can be recorded, and 1 million total coun...

  10. FPS camera sync and reset chassis

    International Nuclear Information System (INIS)

    Yates, G.J.

    1980-06-01

    The sync and reset chassis provides all the circuitry required to synchronize an event to be studied, a remote free-running focus projection and scanning (FPS) data-acquisition TV camera, and a video signal recording system. The functions, design, and operation of this chassis are described in detail

  11. The Legal Implications of Surveillance Cameras

    Science.gov (United States)

    Steketee, Amy M.

    2012-01-01

    The nature of school security has changed dramatically over the last decade. Schools employ various measures, from metal detectors to identification badges to drug testing, to promote the safety and security of staff and students. One of the increasingly prevalent measures is the use of security cameras. In fact, the U.S. Department of Education…

  12. A novel super-resolution camera model

    Science.gov (United States)

    Shao, Xiaopeng; Wang, Yi; Xu, Jie; Wang, Lin; Liu, Fei; Luo, Qiuhua; Chen, Xiaodong; Bi, Xiangli

    2015-05-01

    Aiming to realize super resolution(SR) to single image and video reconstruction, a super resolution camera model is proposed for the problem that the resolution of the images obtained by traditional cameras behave comparatively low. To achieve this function we put a certain driving device such as piezoelectric ceramics in the camera. By controlling the driving device, a set of continuous low resolution(LR) images can be obtained and stored instantaneity, which reflect the randomness of the displacements and the real-time performance of the storage very well. The low resolution image sequences have different redundant information and some particular priori information, thus it is possible to restore super resolution image factually and effectively. The sample method is used to derive the reconstruction principle of super resolution, which analyzes the possible improvement degree of the resolution in theory. The super resolution algorithm based on learning is used to reconstruct single image and the variational Bayesian algorithm is simulated to reconstruct the low resolution images with random displacements, which models the unknown high resolution image, motion parameters and unknown model parameters in one hierarchical Bayesian framework. Utilizing sub-pixel registration method, a super resolution image of the scene can be reconstructed. The results of 16 images reconstruction show that this camera model can increase the image resolution to 2 times, obtaining images with higher resolution in currently available hardware levels.

  13. Face identification in videos from mobile cameras

    NARCIS (Netherlands)

    Mu, Meiru; Spreeuwers, Lieuwe Jan; Veldhuis, Raymond N.J.

    2014-01-01

    It is still challenging to recognize faces reliably in videos from mobile camera, although mature automatic face recognition technology for still images has been available for quite some time. Suppose we want to be alerted when suspects appear in the recording of a police Body-Cam, even a good face

  14. A multidetector scintillation camera with 254 channels

    DEFF Research Database (Denmark)

    Sveinsdottir, E; Larsen, B; Rommer, P

    1977-01-01

    A computer-based scintillation camera has been designed for both dynamic and static radionuclide studies. The detecting head has 254 independent sodium iodide crystals, each with a photomultiplier and amplifier. In dynamic measurements simultaneous events can be recorded, and 1 million total counts...

  15. Digital Camera Project Fosters Communication Skills

    Science.gov (United States)

    Fisher, Ashley; Lazaros, Edward J.

    2009-01-01

    This article details the many benefits of educators' use of digital camera technology and provides an activity in which students practice taking portrait shots of classmates, manipulate the resulting images, and add language arts practice by interviewing their subjects to produce a photo-illustrated Word document. This activity gives…

  16. Phase camera experiment for Advanced Virgo

    NARCIS (Netherlands)

    Agatsuma, Kazuhiro; Van Beuzekom, Martin; Van Der Schaaf, Laura; Van Den Brand, Jo

    2016-01-01

    We report on a study of the phase camera, which is a frequency selective wave-front sensor of a laser beam. This sensor is utilized for monitoring sidebands produced by phase modulations in a gravitational wave (GW) detector. Regarding the operation of the GW detectors, the laser

  17. Integrating Gigabit ethernet cameras into EPICS at Diamond light source

    International Nuclear Information System (INIS)

    Cobb, T.

    2012-01-01

    At Diamond Light Source a range of cameras are used to provide images for diagnostic purposes in both the accelerator and photo beamlines. The accelerator and existing beamlines use Point Grey Flea and Flea2 Firewire cameras. We have selected Gigabit Ethernet cameras supporting GigE Vision for our new photon beamlines. GigE Vision is an interface standard for high speed Ethernet cameras which encourages inter-operability between manufacturers. This paper describes the challenges encountered while integrating GigE Vision cameras from a range of vendors into EPICS. GigE Vision cameras appear to be more reliable than the Firewire cameras, and the simple cabling makes much easier to move the cameras to different positions. Upcoming power over Ethernet versions of the cameras will reduce the number of cables still further

  18. New nuclear medicine gamma camera systems

    International Nuclear Information System (INIS)

    Villacorta, Edmundo V.

    1997-01-01

    The acquisition of the Open E.CAM and DIACAM gamma cameras by Makati Medical Center is expected to enhance the capabilities of its nuclear medicine facilities. When used as an aid to diagnosis, nuclear medicine entails the introduction of a minute amount of radioactive material into the patient; thus, no reaction or side-effect is expected. When it reaches the particular target organ, depending on the radiopharmaceutical, a lesion will appear as a decrease (cold) area or increase (hot) area in the radioactive distribution as recorded byu the gamma cameras. Gamma camera images in slices or SPECT (Single Photon Emission Computer Tomography), increase the sensitivity and accuracy in detecting smaller and deeply seated lesions, which otherwise may not be detected in the regular single planar images. Due to the 'open' design of the equipment, claustrophobic patients will no longer feel enclosed during the procedure. These new gamma cameras yield improved resolution and superb image quality, and the higher photon sensitivity shortens imaging acquisition time. The E.CAM, which is the latest generation gamma camera, is featured by its variable angle dual-head system, the only one available in the Philipines, and the excellent choice for Myocardial Perfusion Imaging (MPI). From the usual 45 minutes, the acquisition time for gated SPECT imaging of the heart has now been remarkably reduced to 12 minutes. 'Gated' infers snap-shots of the heart in selected phases of its contraction and relaxation as triggered by ECG. The DIACAM is installed in a room with access outside the main entrance of the department, intended specially for bed-borne patients. Both systems are equipped with a network of high performance Macintosh ICOND acquisition and processing computers. Added to the hardware is the ICON processing software which allows total simultaneous acquisition and processing capabilities in the same operator's terminal. Video film and color printers are also provided. Together

  19. Optical coating uniformity of 200mm (8") diameter precut wafers

    Science.gov (United States)

    Burt, Travis C.; Fisher, Mark; Brown, Dean; Troiani, David

    2017-02-01

    Automated spectroscopic profiling (mapping) of a 200 mm diameter near infrared high reflector (centered at 1064 nm) are presented. Spatial resolution at 5 mm or less was achieved using a 5 mm × 1.5 mm monochromatic beam. Reflection changes of 1.0% across the wafer diameter were observed under s-polarized and p- polarized conditions. Redundancy was established for each chord by re-measuring the center of the wafer and reproducibility of approximately used to measure the reflectance and transmittance of a sample across a range of angles (θi) at near normal angles of incidence (AOI). A recent development by Agilent Technologies, the Cary 7000 Universal Measurement Spectrophotometer (UMS) combines both reflection and transmission measurements from the same patch of a sample's surface in a single automated platform for angles of incidence in the range 5°use of MPS on the Cary 7000 UMS with rotational (Φ) and vertical (z) sample positioning control. MPS(θi,Φ,z) provides for automated unattended multi-angle R/T analysis of at 200 mm diameter samples with the goal to provide better spectroscopic measurement feedback into large wafer manufacturing to ensure yields are maximized, product quality is better controlled and waste is reduced before further down-stream processing.

  20. QM/MM Calculations with deMon2k

    Directory of Open Access Journals (Sweden)

    Dennis R. Salahub

    2015-03-01

    Full Text Available The density functional code deMon2k employs a fitted density throughout (Auxiliary Density Functional Theory, which offers a great speed advantage without sacrificing necessary accuracy. Powerful Quantum Mechanical/Molecular Mechanical (QM/MM approaches are reviewed. Following an overview of the basic features of deMon2k that make it efficient while retaining accuracy, three QM/MM implementations are compared and contrasted. In the first, deMon2k is interfaced with the CHARMM MM code (CHARMM-deMon2k; in the second MM is coded directly within the deMon2k software; and in the third the Chemistry in Ruby (Cuby wrapper is used to drive the calculations. Cuby is also used in the context of constrained-DFT/MM calculations. Each of these implementations is described briefly; pros and cons are discussed and a few recent applications are described briefly. Applications include solvated ions and biomolecules, polyglutamine peptides important in polyQ neurodegenerative diseases, copper monooxygenases and ultra-rapid electron transfer in cryptochromes.

  1. Photogrammetric Applications of Immersive Video Cameras

    Science.gov (United States)

    Kwiatek, K.; Tokarczyk, R.

    2014-05-01

    The paper investigates immersive videography and its application in close-range photogrammetry. Immersive video involves the capture of a live-action scene that presents a 360° field of view. It is recorded simultaneously by multiple cameras or microlenses, where the principal point of each camera is offset from the rotating axis of the device. This issue causes problems when stitching together individual frames of video separated from particular cameras, however there are ways to overcome it and applying immersive cameras in photogrammetry provides a new potential. The paper presents two applications of immersive video in photogrammetry. At first, the creation of a low-cost mobile mapping system based on Ladybug®3 and GPS device is discussed. The amount of panoramas is much too high for photogrammetric purposes as the base line between spherical panoramas is around 1 metre. More than 92 000 panoramas were recorded in one Polish region of Czarny Dunajec and the measurements from panoramas enable the user to measure the area of outdoors (adverting structures) and billboards. A new law is being created in order to limit the number of illegal advertising structures in the Polish landscape and immersive video recorded in a short period of time is a candidate for economical and flexible measurements off-site. The second approach is a generation of 3d video-based reconstructions of heritage sites based on immersive video (structure from immersive video). A mobile camera mounted on a tripod dolly was used to record the interior scene and immersive video, separated into thousands of still panoramas, was converted from video into 3d objects using Agisoft Photoscan Professional. The findings from these experiments demonstrated that immersive photogrammetry seems to be a flexible and prompt method of 3d modelling and provides promising features for mobile mapping systems.

  2. Voice Controlled Stereographic Video Camera System

    Science.gov (United States)

    Goode, Georgianna D.; Philips, Michael L.

    1989-09-01

    For several years various companies have been developing voice recognition software. Yet, there are few applications of voice control in the robotics field and virtually no examples of voice controlled three dimensional (3-D) systems. In late 1987 ARD developed a highly specialized, voice controlled 3-D vision system for use in remotely controlled, non-tethered robotic applications. The system was designed as an operator's aid and incorporates features thought to be necessary or helpful in remotely maneuvering a vehicle. Foremost is the three dimensionality of the operator's console display. An image that provides normal depth perception cues over a range of depths greatly increases the ease with which an operator can drive a vehicle and investigate its environment. The availability of both vocal and manual control of all system functions allows the operator to guide the system according to his personal preferences. The camera platform can be panned +/-178 degrees and tilted +/-30 degrees for a full range of view of the vehicle's environment. The cameras can be zoomed and focused for close inspection of distant objects, while retaining substantial stereo effect by increasing the separation between the cameras. There is a ranging and measurement function, implemented through a graphical cursor, which allows the operator to mark objects in a scene to determine their relative positions. This feature will be helpful in plotting a driving path. The image seen on the screen is overlaid with icons and digital readouts which provide information about the position of the camera platform, the range to the graphical cursor and the measurement results. The cursor's "range" is actually the distance from the cameras to the object on which the cursor is resting. Other such features are included in the system and described in subsequent sections of this paper.

  3. Electron Bunch Length Measurement for LCLS at SLAC

    International Nuclear Information System (INIS)

    Zelazny, M.; Allison, S.; Chevtsov, Sergei; Emma, P.; Kotturi, K.d.; Loos, H.; Peng, S.; Rogind, D.; Straumann, T.

    2007-01-01

    At Stanford Linear Accelerator Center (SLAC) a Bunch Length Measurement system has been developed to measure the length of the electron bunch for its new Linac Coherent Light Source (LCLS). This destructive measurement uses a transverse-mounted RF deflector (TCAV) to vertically streak the electron beam and an image taken with an insertable screen and a camera. The device control software was implemented with the Experimental Physics and Industrial Control System (EPICS) toolkit. The analysis software was implemented in Matlab(trademark) using the EPICS/Channel Access Interface for Scilab(trademark) and Matlab(trademark) (labCA). This architecture allowed engineers and physicists to develop and integrate their control and analysis without duplication of effort

  4. Electron Bunch Length Measurement for LCLS at SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Zelazny, M.; Allison, S.; Chevtsov, Sergei; Emma, P.; Kotturi, K.d.; Loos, H.; Peng, S.; Rogind, D.; Straumann, T.; /SLAC

    2007-10-04

    At Stanford Linear Accelerator Center (SLAC) a Bunch Length Measurement system has been developed to measure the length of the electron bunch for its new Linac Coherent Light Source (LCLS). This destructive measurement uses a transverse-mounted RF deflector (TCAV) to vertically streak the electron beam and an image taken with an insertable screen and a camera. The device control software was implemented with the Experimental Physics and Industrial Control System (EPICS) toolkit. The analysis software was implemented in Matlab{trademark} using the EPICS/Channel Access Interface for Scilab{trademark} and Matlab{trademark} (labCA). This architecture allowed engineers and physicists to develop and integrate their control and analysis without duplication of effort.

  5. Trace analysis for 300 MM wafers and processes with TXRF

    International Nuclear Information System (INIS)

    Nutsch, A.; Erdmann, V.; Zielonka, G.; Pfitzner, L.; Ryssel, H.

    2000-01-01

    Efficient fabrication of semiconductor devices is combined with an increasing size of silicon wafers. The contamination level of processes, media, and equipment has to decrease continuously. A new test laboratory for 300 mm was installed in view of the above mentioned aspects. Aside of numerous processing tools this platform consist electrical test methods, particle detection, vapor phase decomposition (VPD) preparation, and TXRF. The equipment is installed in a cleanroom. It is common to perform process or equipment control, development, evaluation and qualification with monitor wafers. The evaluation and the qualification of 300 mm equipment require direct TXRF on 300 mm wafers. A new TXRF setup was installed due to the wafer size of 300 mm. The 300 mm TXRF is equipped with tungsten and molybdenum anode. This combination allows a sensitive detection of elements with fluorescence energy below 10 keV for tungsten excitation. The molybdenum excitation enables the detection of a wide variety of elements. The detection sensitivity for the tungsten anode excited samples is ten times higher than for molybdenum anode measured samples. The system is calibrated with 1 ng Ni. This calibration shows a stability within 5 % when monitored to control system stability. Decreasing the amount of Ni linear results in a linear decrease of the measured Ni signal. This result is verified for a range of elements by multielement samples. New designs demand new processes and materials, e.g. ferroelectric layers and copper. The trace analysis of many of these materials is supported by the higher excitation energy of the molybdenum anode. Reclaim and recycling of 300 mm wafers demand for an accurate contamination control of the processes to avoid cross contamination. Polishing or etching result in modified surfaces. TXRF as a non-destructive test method allows the simultaneously detection of a variety of elements on differing surfaces in view of contamination control and process

  6. Control of the movement of a ROV camera; Controle de posicionamento da camera de um ROV

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Alexandre S. de; Dutra, Max Suell [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE); Reis, Ney Robinson S. dos [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Santos, Auderi V. dos [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil)

    2004-07-01

    The ROV's (Remotely Operated Vehicles) are used for installation and maintenance of underwater exploration systems in the oil industry. These systems are operated in distant areas thus being of essential importance the use of a cameras for the visualization of the work area. The synchronization necessary in the accomplishment of the tasks when operating the manipulator and the movement of the camera for the operator is a complex task. For the accomplishment of this synchronization is presented in this work the analysis of the interconnection of the systems. The concatenation of the systems is made through the interconnection of the electric signals of the proportional valves of the actuators of the manipulator with the signals of the proportional valves of the actuators of the camera. With this interconnection the approach accompaniment of the movement of the manipulator for the camera, keeping the object of the visualization of the field of vision of the operator is obtained. (author)

  7. Progress in long scale length laser plasma interactions

    Science.gov (United States)

    Glenzer, S. H.; Arnold, P.; Bardsley, G.; Berger, R. L.; Bonanno, G.; Borger, T.; Bower, D. E.; Bowers, M.; Bryant, R.; Buckman, S.; Burkhart, S. C.; Campbell, K.; Chrisp, M. P.; Cohen, B. I.; Constantin, C.; Cooper, F.; Cox, J.; Dewald, E.; Divol, L.; Dixit, S.; Duncan, J.; Eder, D.; Edwards, J.; Erbert, G.; Felker, B.; Fornes, J.; Frieders, G.; Froula, D. H.; Gardner, S. D.; Gates, C.; Gonzalez, M.; Grace, S.; Gregori, G.; Greenwood, A.; Griffith, R.; Hall, T.; Hammel, B. A.; Haynam, C.; Heestand, G.; Henesian, M.; Hermes, G.; Hinkel, D.; Holder, J.; Holdner, F.; Holtmeier, G.; Hsing, W.; Huber, S.; James, T.; Johnson, S.; Jones, O. S.; Kalantar, D.; Kamperschroer, J. H.; Kauffman, R.; Kelleher, T.; Knight, J.; Kirkwood, R. K.; Kruer, W. L.; Labiak, W.; Landen, O. L.; Langdon, A. B.; Langer, S.; Latray, D.; Lee, A.; Lee, F. D.; Lund, D.; MacGowan, B.; Marshall, S.; McBride, J.; McCarville, T.; McGrew, L.; Mackinnon, A. J.; Mahavandi, S.; Manes, K.; Marshall, C.; Menapace, J.; Mertens, E.; Meezan, N.; Miller, G.; Montelongo, S.; Moody, J. D.; Moses, E.; Munro, D.; Murray, J.; Neumann, J.; Newton, M.; Ng, E.; Niemann, C.; Nikitin, A.; Opsahl, P.; Padilla, E.; Parham, T.; Parrish, G.; Petty, C.; Polk, M.; Powell, C.; Reinbachs, I.; Rekow, V.; Rinnert, R.; Riordan, B.; Rhodes, M.; Roberts, V.; Robey, H.; Ross, G.; Sailors, S.; Saunders, R.; Schmitt, M.; Schneider, M. B.; Shiromizu, S.; Spaeth, M.; Stephens, A.; Still, B.; Suter, L. J.; Tietbohl, G.; Tobin, M.; Tuck, J.; Van Wonterghem, B. M.; Vidal, R.; Voloshin, D.; Wallace, R.; Wegner, P.; Whitman, P.; Williams, E. A.; Williams, K.; Winward, K.; Work, K.; Young, B.; Young, P. E.; Zapata, P.; Bahr, R. E.; Seka, W.; Fernandez, J.; Montgomery, D.; Rose, H.

    2004-12-01

    The first experiments on the National Ignition Facility (NIF) have employed the first four beams to measure propagation and laser backscattering losses in large ignition-size plasmas. Gas-filled targets between 2 and 7 mm length have been heated from one side by overlapping the focal spots of the four beams from one quad operated at 351 nm (3ω) with a total intensity of 2 × 1015 W cm-2. The targets were filled with 1 atm of CO2 producing up to 7 mm long homogeneously heated plasmas with densities of ne = 6 × 1020 cm-3 and temperatures of Te = 2 keV. The high energy in an NIF quad of beams of 16 kJ, illuminating the target from one direction, creates unique conditions for the study of laser-plasma interactions at scale lengths not previously accessible. The propagation through the large-scale plasma was measured with a gated x-ray imager that was filtered for 3.5 keV x-rays. These data indicate that the beams interact with the full length of this ignition-scale plasma during the last ~1 ns of the experiment. During that time, the full aperture measurements of the stimulated Brillouin scattering and stimulated Raman scattering show scattering into the four focusing lenses of 3% for the smallest length (~2 mm), increasing to 10-12% for ~7 mm. These results demonstrate the NIF experimental capabilities and further provide a benchmark for three-dimensional modelling of the laser-plasma interactions at ignition-size scale lengths.

  8. VUV Testing of Science Cameras at MSFC: QE Measurement of the CLASP Flight Cameras

    Science.gov (United States)

    Champey, Patrick R.; Kobayashi, Ken; Winebarger, A.; Cirtain, J.; Hyde, D.; Robertson, B.; Beabout, B.; Beabout, D.; Stewart, M.

    2015-01-01

    The NASA Marshall Space Flight Center (MSFC) has developed a science camera suitable for sub-orbital missions for observations in the UV, EUV and soft X-ray. Six cameras were built and tested for the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP), a joint National Astronomical Observatory of Japan (NAOJ) and MSFC sounding rocket mission. The CLASP camera design includes a frame-transfer e2v CCD57-10 512x512 detector, dual channel analog readout electronics and an internally mounted cold block. At the flight operating temperature of -20 C, the CLASP cameras achieved the low-noise performance requirements (less than or equal to 25 e- read noise and greater than or equal to 10 e-/sec/pix dark current), in addition to maintaining a stable gain of approximately equal to 2.0 e-/DN. The e2v CCD57-10 detectors were coated with Lumogen-E to improve quantum efficiency (QE) at the Lyman- wavelength. A vacuum ultra-violet (VUV) monochromator and a NIST calibrated photodiode were employed to measure the QE of each camera. Four flight-like cameras were tested in a high-vacuum chamber, which was configured to operate several tests intended to verify the QE, gain, read noise, dark current and residual non-linearity of the CCD. We present and discuss the QE measurements performed on the CLASP cameras. We also discuss the high-vacuum system outfitted for testing of UV and EUV science cameras at MSFC.

  9. Influence of Striking Edge Radius (2 mm versus 8 mm) on Instrumented Charpy Data and Absorbed Energies

    Energy Technology Data Exchange (ETDEWEB)

    Lucon, E.

    2008-08-15

    The most commonly used test standards for performing Charpy impact tests (ISO 148 and ASTM E 23) envisage the use of strikers having different radii of the striking edge, i.e. 2 mm (ISO) and 8 mm (ASTM). The effect of striker geometry on Charpy results was extensively studied in the past in terms of absorbed energy measured by the machine encoder, but few investigations are available on the influence of striker configuration on the results of instrumented Charpy tests (characteristic forces, displacements and integrated energy). In this paper, these effects are investigated based on the analysis of published results from three interlaboratory studies and some unpublished Charpy data obtained at SCK-CEN. The instrumented variables which are the most sensitive to the radius of the striking edge are the maximum force and its corresponding displacement, with 8mm-strikers providing systematically higher values. Absorbed energies, obtained both from the instrumented trace and from the pendulum encoder, are almost insensitive to the type of striker up to 200 J. For higher energy levels, the values obtained from 8mm strikers become progressively larger. Data scatter is generally higher for 2mm-strikers.

  10. [Evaluation of small semiconductor gamma camera--simulation of sentinel lymph node biopsy by using a trial product of clinical type gamma camera].

    Science.gov (United States)

    Oda, Takaaki; Hayama, Kazuhide; Tsuchimochi, Makoto

    2009-03-01

    This study was to verify the performance of three different collimators that were equipped to the clinical application type of small semiconductor gamma camera (SSGC) for radio-guided surgery. We also wanted to see if the clinical application type could be effective to detect sentinel nodes in simulation studies for sentinel lymph node biopsy. The camera head consisted of a pixelized CdTe module (32 x 32 individual elements, total of 1,024 pixels) (Acrorad Co. Ltd., Tokyo, Japan). The field of view was 44.8 mm x 44.8 mm. The clinical application type of this gamma camera had three exchangeable collimators; standard, high sensitivity and high resolution (ST, HS, HR). Energy resolution, full-width at half-maximum (FWHM), of the CdTe detector attached with the standard collimator was 6.9% at 141 keV (99mTc). The spatial resolution, represented by FWHM, had a mean value of 1.59 mm. The data was comparable to the results of the prototype SSGC. The simulation studies showed that HS could more sensitively detect the simulated nodes than ST and HR did, and HR could more reliably distinguish the simulated sentinel node that situated close to the injection site than other two collimators did. However the depiction was interfered by the higher background radiation levels. We suggest that this SSGC clinical application type may provide advantages over the standard system for isolating sentinel lymph nodes biopsy. We also believe that the SSGC may aid surgeons in identifying target tissues when performing radio-guided surgery.

  11. Mechanical Properties Comparing Composite Fiber Length to Amalgam

    Directory of Open Access Journals (Sweden)

    Richard C. Petersen

    2016-01-01

    Full Text Available Photocure fiber-reinforced composites (FRCs with varying chopped quartz-fiber lengths were incorporated into a dental photocure zirconia-silicate particulate-filled composite (PFC for mechanical test comparisons with a popular commercial spherical-particle amalgam. FRC lengths included 0.5-mm, 1.0 mm, 2.0 mm, and 3.0 mm all at a constant 28.2 volume percent. Four-point fully articulated fixtures were used according to American Standards Test Methods with sample dimensions of 2×2×50 mm3 across a 40 mm span to provide sufficient Euler flexural bending and prevent top-load compressive shear error. Mechanical properties for flexural strength, modulus, yield strength, resilience, work of fracture, critical strain energy release, critical stress intensity factor, and strain were obtained for comparison. Fiber length subsequently correlated with increasing all mechanical properties, p<1.1×10-5. Although the modulus was significantly statistically higher for amalgam than all composites, all FRCs and even the PFC had higher values than amalgam for all other mechanical properties. Because amalgams provide increased longevity during clinical use compared to the standard PFCs, modulus would appear to be a mechanical property that might sufficiently reduce margin interlaminar shear stress and strain-related microcracking that could reduce failure rates. Also, since FRCs were tested with all mechanical properties that statistically significantly increased over the PFC, new avenues for future development could be provided toward surpassing amalgam in clinical longevity.

  12. Calibration of high resolution digital camera based on different photogrammetric methods

    Science.gov (United States)

    Hamid, N. F. A.; Ahmad, A.

    2014-02-01

    This paper presents method of calibrating high-resolution digital camera based on different configuration which comprised of stereo and convergent. Both methods are performed in the laboratory and in the field calibration. Laboratory calibration is based on a 3D test field where a calibration plate of dimension 0.4 m × 0.4 m with grid of targets at different height is used. For field calibration, it uses the same concept of 3D test field which comprised of 81 target points located on a flat ground and the dimension is 9 m × 9 m. In this study, a non-metric high resolution digital camera called Canon Power Shot SX230 HS was calibrated in the laboratory and in the field using different configuration for data acquisition. The aim of the calibration is to investigate the behavior of the internal digital camera whether all the digital camera parameters such as focal length, principal point and other parameters remain the same or vice-versa. In the laboratory, a scale bar is placed in the test field for scaling the image and approximate coordinates were used for calibration process. Similar method is utilized in the field calibration. For both test fields, the digital images were acquired within short period using stereo and convergent configuration. For field calibration, aerial digital images were acquired using unmanned aerial vehicle (UAV) system. All the images were processed using photogrammetric calibration software. Different calibration results were obtained for both laboratory and field calibrations. The accuracy of the results is evaluated based on standard deviation. In general, for photogrammetric applications and other applications the digital camera must be calibrated for obtaining accurate measurement or results. The best method of calibration depends on the type of applications. Finally, for most applications the digital camera is calibrated on site, hence, field calibration is the best method of calibration and could be employed for obtaining accurate

  13. 3D tomographic imaging with the γ-eye planar scintigraphic gamma camera

    Science.gov (United States)

    Tunnicliffe, H.; Georgiou, M.; Loudos, G. K.; Simcox, A.; Tsoumpas, C.

    2017-11-01

    γ-eye is a desktop planar scintigraphic gamma camera (100 mm × 50 mm field of view) designed by BET Solutions as an affordable tool for dynamic, whole body, small-animal imaging. This investigation tests the viability of using γ-eye for the collection of tomographic data for 3D SPECT reconstruction. Two software packages, QSPECT and STIR (software for tomographic image reconstruction), have been compared. Reconstructions have been performed using QSPECT’s implementation of the OSEM algorithm and STIR’s OSMAPOSL (Ordered Subset Maximum A Posteriori One Step Late) and OSSPS (Ordered Subsets Separable Paraboloidal Surrogate) algorithms. Reconstructed images of phantom and mouse data have been assessed in terms of spatial resolution, sensitivity to varying activity levels and uniformity. The effect of varying the number of iterations, the voxel size (1.25 mm default voxel size reduced to 0.625 mm and 0.3125 mm), the point spread function correction and the weight of prior terms were explored. While QSPECT demonstrated faster reconstructions, STIR outperformed it in terms of resolution (as low as 1 mm versus 3 mm), particularly when smaller voxel sizes were used, and in terms of uniformity, particularly when prior terms were used. Little difference in terms of sensitivity was seen throughout.

  14. Characterization of superconducting thin films using mm-wave transmission

    NARCIS (Netherlands)

    Feenstra, B.J; Klaassen, F.C.; van der Marel, D.; Barber, Z.; Perez Pinaya, R.; Decroux, M.; Afsar, MN

    1996-01-01

    We present mm-wave transmission as a complementary technique to characterize the properties of superconducting thin films, obtaining information on both the real and imaginary part of the dielectric function. Examples are given to illustrate the strength of the technique to measure the response of

  15. Security architecture of the M&M mobile agent framework

    Science.gov (United States)

    Marques, Paulo J.; Santos, Nuno F.; Silva, Luis; Silva, Joao G.

    2001-07-01

    In the Mobile Agent programming model, small threads of execution migrate from machine to machine, performing their operations locally. For being able to deploy such a model into real world applications, security is a vital concern. In the M&M project we have developed a system that departures from the traditional platform-based execution model for mobile agents. In M&M there are no agent platforms. Instead there is a component framework that allows the applications to become able of sending and receiving agents by themselves in a straightforward manner. In this paper we examine the security mechanisms available in M&M, and how integration with existing applications is done. One difficult aspect of this work is that all the features must work with the security mechanisms that already exist on the applications. This is so because the components are integrated from within into the applications, which already have security mechanisms in place. Currently, M&M provides features like fine-grain security permissions, encryption of agents and data, certificate distribution using LDAP and cryptographic primitives for agents. For validating the approach and solutions found, we have integrated the framework into several off-the-shelf web servers, having the security mechanisms running, with no problems.

  16. Analysis on MM5 predictions at Sriharikota during northeast ...

    Indian Academy of Sciences (India)

    The objective of this study is to analyse the performance of the PSU-NCAR Mesoscale Model Version 5 (MM5), for northeast monsoon 2008 that includes tropical cyclones – Rashmi, Khai-Muk and Nisha and convective events over Sriharikota region, the rocket launch centre. The impact of objective analysis system using ...

  17. Performance of 4mm impact sprinklers at different spacing within ...

    African Journals Online (AJOL)

    Irrigation Engineers in Zimbabwe use the 12 m x 18 m spacing for the design of the sprayline, using 4 mm nozzle sprinklers. A study was conducted to determine performance and cost effectiveness of other spacings that can be used in sprinkler irrigation systems design. The main targeted spacings were a square layout of ...

  18. Two-port laparoscopic ovarian cystectomy using 3-mm instruments

    Directory of Open Access Journals (Sweden)

    Naoyuki Yoshiki

    2016-05-01

    Conclusion: Two-port laparoscopic ovarian cystectomy using 3-mm instruments is a feasible and safe approach by which surgeons expert in conventional multiport laparoscopy achieve minimally invasive surgery with low morbidity and a low rate of conversion to the conventional approach.

  19. Guide to Films (16 mm) About Ecology, Adaptation and Pollution.

    Science.gov (United States)

    1971

    Synopses of 350 films (16 mm.) on ecology, adaptation of plants and animals to their environment, and environmental pollution are listed alphabetically by title in this guide. It specifies whether the film is black-and-white or color, its running time, and its source. An abbreviated subject index and a directory of sources are also provided. The…

  20. Millimeter wave VAlidation STandard (mm-VAST) antenna

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.

    This document summarizes the main results of the project “Millimeter wave VAlidation STandard (mm-VAST) antenna” completed by the Technical University of Denmark (DTU) in collaboration with Danish company TICRA for the European Space Agency (ESA) under ESA contract no. 4000109866/13/NL/MH....

  1. Robotic versus human camera holding in video-assisted thoracic sympathectomy: a single blind randomized trial of efficacy and safety.

    Science.gov (United States)

    Martins Rua, Joaquim Fernando; Jatene, Fabio Biscegli; de Campos, José Ribas Milanez; Monteiro, Rosangela; Tedde, Miguel Lia; Samano, Marcos Naoyuki; Bernardo, Wanderley M; Das-Neves-Pereira, João Carlos

    2009-02-01

    Our objective is to compare surgical safety and efficacy between robotic and human camera control in video-assisted thoracic sympathectomy. A randomized-controlled-trial was performed. Surgical operation was VATS sympathectomy for hyperhidrosis. The trial compared a voice-controlled robot for holding the endoscopic camera robotic group (Ro) to human assisted group (Hu). Each group included 19 patients. Sympathectomy was achieved by electrodessication of the third ganglion. Operations were filmed and images stored. Two observers quantified the number of involuntary and inappropriate movements and how many times the camera was cleaned. Safety criteria were surgical accidents, pain and aesthetical results; efficacy criteria were: surgical and camera use duration, anhydrosis, length of hospitalization, compensatory hyperhidrosis and patient satisfaction. There was no difference between groups regarding surgical accidents, number of involuntary movements, pain, aesthetical results, general satisfaction, number of lens cleaning, anhydrosis, length of hospitalization, and compensatory hyperhidrosis. The number of contacts of the laparoscopic lens with mediastinal structures was lower in the Ro group (Probotic arm in VATS sympathectomy for hyperhidrosis is as safe but less efficient when compared to a human camera-holding assistant.

  2. World's fastest and most sensitive astronomical camera

    Science.gov (United States)

    2009-06-01

    The next generation of instruments for ground-based telescopes took a leap forward with the development of a new ultra-fast camera that can take 1500 finely exposed images per second even when observing extremely faint objects. The first 240x240 pixel images with the world's fastest high precision faint light camera were obtained through a collaborative effort between ESO and three French laboratories from the French Centre National de la Recherche Scientifique/Institut National des Sciences de l'Univers (CNRS/INSU). Cameras such as this are key components of the next generation of adaptive optics instruments of Europe's ground-based astronomy flagship facility, the ESO Very Large Telescope (VLT). ESO PR Photo 22a/09 The CCD220 detector ESO PR Photo 22b/09 The OCam camera ESO PR Video 22a/09 OCam images "The performance of this breakthrough camera is without an equivalent anywhere in the world. The camera will enable great leaps forward in many areas of the study of the Universe," says Norbert Hubin, head of the Adaptive Optics department at ESO. OCam will be part of the second-generation VLT instrument SPHERE. To be installed in 2011, SPHERE will take images of giant exoplanets orbiting nearby stars. A fast camera such as this is needed as an essential component for the modern adaptive optics instruments used on the largest ground-based telescopes. Telescopes on the ground suffer from the blurring effect induced by atmospheric turbulence. This turbulence causes the stars to twinkle in a way that delights poets, but frustrates astronomers, since it blurs the finest details of the images. Adaptive optics techniques overcome this major drawback, so that ground-based telescopes can produce images that are as sharp as if taken from space. Adaptive optics is based on real-time corrections computed from images obtained by a special camera working at very high speeds. Nowadays, this means many hundreds of times each second. The new generation instruments require these

  3. Evolving Starburst Modeling of FIR/sub-mm/mm Line Emission. III. Application to Nearby Luminous Infrared Galaxies

    OpenAIRE

    Yao, Lihong

    2009-01-01

    In a previous work, we showed that the observed FIR/sub-mm/mm line spectra of a starburst galaxy (M 82) can be successfully modeled in terms of the evolutionary scheme of an ensemble of giant molecular clouds (GMCs) and shells, and such studies can usefully constrain the age(s) or star formation history of a starburst galaxy. In this paper we present a preliminary study of using the template of an ensemble of evolving GMCs/shells we developed for M 82. we apply the model to represent various ...

  4. Charpy impact test results on five materials and NIST verification specimens using instrumented 2-mm and 8-mm strikers

    International Nuclear Information System (INIS)

    Nanstad, R.K.; Sokolov, M.A.

    1995-01-01

    The Heavy-Section Steel Irradiation Program at Oak Ridge National Laboratory is involved in two cooperative projects, with international participants, both of which involve Charpy V-notch impact tests with instrumented strikers of 2mm and 8mm radii. Two heats of A 533 grade B class I pressure vessel steel and a low upper-shelf (LUS) submerged-arc (SA) weld were tested on the same Charpy machine, while one heat of a Russian Cr-Mo-V forging steel and a high upper-shelf (HUS) SA weld were tested on two different machines. The number of replicate tests at any one temperature ranged from 2 to 46 specimens. Prior to testing with each striker, verification specimens at the low, high, and super high energy levels from the National Institute of Standards and Technology (NIST) were tested. In the two series of verification tests, the tests with the 2mm striker met the requirements at the low and high energy levels but not at the super high energy. For one plate, the 2mm striker showed somewhat higher average absorbed energies than those for the 8-mm striker at all three test temperatures. For the second plate and the LUS weld, however, the 2mm striker showed somewhat lower energies at both test temperatures. For the Russian forging steel and the HUS weld, tests were conducted over a range of temperatures with tests at one laboratory using the 8mm striker and tests at a second laboratory using the 2mm striker. Lateral expansion was measured for all specimens and the results are compared with the absorbed energy results. The overall results showed generally good agreement (within one standard deviation) in energy measurements by the two strikers. Load-time traces from the instrumented strikers were also compared and used to estimate shear fracture percentage. Four different formulas from the European Structural Integrity Society draft standard for instrumented Charpy test are compared and a new formula is proposed for estimation of percent shear from the force-time trace

  5. Preoperative CT planning of screw length in arthroscopic Latarjet.

    Science.gov (United States)

    Hardy, Alexandre; Gerometta, Antoine; Granger, Benjamin; Massein, Audrey; Casabianca, Laurent; Pascal-Moussellard, Hugues; Loriaut, Philippe

    2018-01-01

    The Latarjet procedure has shown its efficiency for the treatment of anterior shoulder dislocation. The success of this technique depends on the correct positioning and fusion of the bone block. The length of the screws that fix the bone block can be a problem. They can increase the risk of non-union if too short or be the cause of nerve lesion or soft tissue discomfort if too long. Suprascapular nerve injuries have been reported during shoulder stabilisation surgery up to 6 % of the case. Bone block non-union depending on the series is found around 20 % of the cases. The purpose of this study was to evaluate the efficiency of this CT preoperative planning to predict optimal screws length. The clinical importance of this study lies in the observation that it is the first study to evaluate the efficiency of CT planning to predict screw length. Inclusion criteria were patients with chronic anterior instability of the shoulder with an ISIS superior to 4. Exclusion criteria were patients with multidirectional instability or any previous surgery on this shoulder. Thirty patients were included prospectively, 11 of them went threw a CT planning, before their arthroscopic Latarjet. Optimal length of both screws was calculated, adding the size of the coracoid at 5 and 15 mm from the tip to the glenoid. Thirty-two-mm screws were used for patients without planning. On a post-operative CT scan with 3D reconstruction, the distance between the screw tip and the posterior cortex was measured. A one-sample Wilcoxon test was used to compare the distance from the tip of the screw to an acceptable positioning of ±2 mm from the posterior cortex. In the group without planning, screw 1 tended to differ from the acceptable positioning: mean 3.44 mm ± 3.13, med 2.9 mm, q1; q3 [0.6; 4.75] p = 0.1118, and screw 2 differed significantly from the acceptable position: mean 4.83 mm ± 4.11, med 3.7 mm, q1; q3 [1.7; 5.45] p = 0.0045. In the group with planning, position of

  6. Principle of some gamma cameras (efficiencies, limitations, development)

    International Nuclear Information System (INIS)

    Allemand, R.; Bourdel, J.; Gariod, R.; Laval, M.; Levy, G.; Thomas, G.

    1975-01-01

    The quality of scintigraphic images is shown to depend on the efficiency of both the input collimator and the detector. Methods are described by which the quality of these images may be improved by adaptations to either the collimator (Fresnel zone camera, Compton effect camera) or the detector (Anger camera, image amplification camera). The Anger camera and image amplification camera are at present the two main instruments whereby acceptable space and energy resolutions may be obtained. A theoretical comparative study of their efficiencies is carried out, independently of their technological differences, after which the instruments designed or under study at the LETI are presented: these include the image amplification camera, the electron amplifier tube camera using a semi-conductor target CdTe and HgI 2 detector [fr

  7. GPM GROUND VALIDATION DC-8 CAMERA NADIR GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation DC-8 Camera Nadir GCPEx dataset contains geo-located visible-wavelength imagery of the ground obtained from the nadir camera aboard the...

  8. GPM GROUND VALIDATION DC-8 CAMERA NADIR GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation DC-8 Camera Nadir GCPEx dataset contains geo-located, visible-wavelength imagery of the ground obtained from the nadir camera aboard the...

  9. Declarative camera control for automatic cinematography

    Energy Technology Data Exchange (ETDEWEB)

    Christianson, D.B.; Anderson, S.E.; Li-wei He [Univ. of Washington, Seattle, WA (United States)] [and others

    1996-12-31

    Animations generated by interactive 3D computer graphics applications are typically portrayed either from a particular character`s point of view or from a small set of strategically-placed viewpoints. By ignoring camera placement, such applications fail to realize important storytelling capabilities that have been explored by cinematographers for many years. In this paper, we describe several of the principles of cinematography and show how they can be formalized into a declarative language, called the Declarative Camera Control Language (DCCL). We describe the application of DCCL within the context of a simple interactive video game and argue that DCCL represents cinematic knowledge at the same level of abstraction as expert directors by encoding 16 idioms from a film textbook. These idioms produce compelling animations, as demonstrated on the accompanying videotape.

  10. Advanced EVA Suit Camera System Development Project

    Science.gov (United States)

    Mock, Kyla

    2016-01-01

    The National Aeronautics and Space Administration (NASA) at the Johnson Space Center (JSC) is developing a new extra-vehicular activity (EVA) suit known as the Advanced EVA Z2 Suit. All of the improvements to the EVA Suit provide the opportunity to update the technology of the video imagery. My summer internship project involved improving the video streaming capabilities of the cameras that will be used on the Z2 Suit for data acquisition. To accomplish this, I familiarized myself with the architecture of the camera that is currently being tested to be able to make improvements on the design. Because there is a lot of benefit to saving space, power, and weight on the EVA suit, my job was to use Altium Design to start designing a much smaller and simplified interface board for the camera's microprocessor and external components. This involved checking datasheets of various components and checking signal connections to ensure that this architecture could be used for both the Z2 suit and potentially other future projects. The Orion spacecraft is a specific project that may benefit from this condensed camera interface design. The camera's physical placement on the suit also needed to be determined and tested so that image resolution can be maximized. Many of the options of the camera placement may be tested along with other future suit testing. There are multiple teams that work on different parts of the suit, so the camera's placement could directly affect their research or design. For this reason, a big part of my project was initiating contact with other branches and setting up multiple meetings to learn more about the pros and cons of the potential camera placements we are analyzing. Collaboration with the multiple teams working on the Advanced EVA Z2 Suit is absolutely necessary and these comparisons will be used as further progress is made for the overall suit design. This prototype will not be finished in time for the scheduled Z2 Suit testing, so my time was

  11. Dynamic gamma camera scintigraphy in primary hypoovarism

    International Nuclear Information System (INIS)

    Peshev, N.; Mladenov, B.; Topalov, I.; Tsanev, Ts.

    1988-01-01

    Twenty-seven patients with primary hypoovarism and 10 controls were examined. After intravenous injection of 111 to 175 MBq 99m Tc pertechnetate, dynamic gamma camera scintigraphy for 15 minutes was carried out. In the patients with primary amenorrhea no functioning ovarial tissue was visualized or the ovaries were diminished in size, strongly reduced and non-homogenous accumulation of the radionuclide with unclear and uneven delineation were observed. In the patients with primary infertility, the gamma camera investigation gave information not only about the presence of ovarial parenchyma, but about the extent of the inflammatory process, too. In the patients after surgical intervention, the dynamic radioisotope investigation gave information about the volume and the site of the surgical intervention, as well as about the conditions of the residual parenchyma

  12. Evaluation of 4 mm implants in mandibular edentulous patients with reduced bone height. Surgical preliminary results

    Directory of Open Access Journals (Sweden)

    J.L. Calvo-Guirado

    2014-06-01

    Full Text Available Aim: Growing evidence has suggested the utility of short dental implants for oral reconstructive procedures in clinical situations of limited vertical bone height. The aim of this short comunication was to evaluate the clinical use of implants < 10 mm in length and to determine short implant-supported prosthesis success in the atrophic jaw. Materials and methods: Six women and three men were recruited for the treatment of edentulous mandibles. A total of 6 implants were inserted in each patient: two anterior implants of conventional lenght and four posterior 4 mm Titanium Zirconium (TiZr implants. The insertion torque and bone denisty were evaluated. Results: The mean insertion torque for the 4 mm implants was lower than for conventional ones, without any statistical difference. Moreover, most of the patients (88% showed a D2 bone type. Conclusion: The provision of short implant-supported prostheses in patients with atrophic alveolar ridges appears to be a successful treatment option in the short term; however, more scientific evidence is needed for the long term.

  13. Test results of an electromagnetic calorimeter with 0. 5 mm scintillating fibers readout

    Energy Technology Data Exchange (ETDEWEB)

    Badier, J.; Bouhemaid, N.; Buontempo, S.; Busson, P.; Caloba, L.; Cattaneo, P.; Charlot, C.; Chekhtman, A.; Cousinou, M.C.; Dagoret, S.; Dell' Acqua, A.; Ereditato, A.; Ferrari, R.; Fouchez, D.; Fredj, L.; Fumagalli, G.; Gaillard, J.M.; Goggi, G.; Gomes, A.; Hansl-Kozanecka, T.; Henriques, A.; Kovacs, F.; Linssen, L.; Livan, M.; Lory, J.; Maio, A.; Michel, B.; Montarou, G.; Nacasch, R.; Nagy, E.; Paar, H.P.; Pallin, D.; Pennacchio, E.; Peralta, L.; Poggioli, L.; Polesello, G.; Riccardi, F.; Rimoldi, A.; Seixas, J.M.; Sivertz, M.; Souza, M.N.; Thome, Z.D.; Tisserant, S.; Tome, B.; Vazeille, F.; Vercesi, V.; Wigmans, R.; Zitoun, R. (LPNHE, Ecole Polytechnique, Palaiseau (France) LPPCF, Univ. Blaise Pascal, Clermont-Ferrand (France) Univ. di Napoli, Napoli (Italy) INFN, Napoli (Italy) COPPE/EE/UFRJ, Rio de Janeiro, RJ (Brazil) Univ. di Pavia (Italy) INFN, Pavia (Italy) CPPM, Marseille (France) LPNHE, Univ. Paris VI and VII (France) CERN, Geneva (Switzerland) LIP, Lisbon (Portugal) Univ. o; RD1 Collaboration

    1994-01-01

    We report on an experimental study of the performance of an electromagnetic calorimeter consisting of thin (0.5 mm diameter) scintillating plastic fibers embedded in lead. Because of the small sampling fraction (3.5% for minimum ionizing particles), this detector is quite compact, with an effective radiation length of 7.2 mm and a Moliere radius of 20 mm. Because of the very frequent shower sampling provided by the fibers, the energy resolution is nevertheless good: 9.2%/[radical]E(GeV) for electromagnetic (e.m.) showers, with a small, angle dependent constant term. A non-uniformity in the response is observed at the 2% level across the calorimeter. In spite of the small sampling fraction the light yield is not a limiting factor in this calorimeter: we measured [approx]500 photoelectrons per GeV shower energy. The position resolution for electrons and two e.m. showers separation have been studied. The fibers sticking out of the back of the detector do not appear to affect the measurements of hadronic showers. (orig.)

  14. Test stand for non-uniformity correction of microbolometer focal plane arrays used in thermal cameras

    Science.gov (United States)

    Krupiński, Michał; Bareła, Jaroslaw; Firmanty, Krzysztof; Kastek, Mariusz

    2013-10-01

    Uneven response of particular detectors (pixels) to the same incident power of infrared radiation is an inherent feature of microbolometer focal plane arrays. As a result an image degradation occurs, known as Fixed Pattern Noise (FPN), which distorts the thermal representation of an observed scene and impairs the parameters of a thermal camera. In order to compensate such non-uniformity, several NUC correction methods are applied in digital data processing modules implemented in thermal cameras. Coefficients required to perform the non-uniformity correction procedure (NUC coefficients) are determined by calibrating the camera against uniform radiation sources (blackbodies). Non-uniformity correction is performed in a digital processing unit in order to remove FPN pattern in the registered thermal images. Relevant correction coefficients are calculated on the basis of recorded detector responses to several values of radiant flux emitted from reference IR radiation sources (blackbodies). The measurement of correction coefficients requires specialized setup, in which uniform, extended radiation sources with high temperature stability are one of key elements. Measurement stand for NUC correction developed in Institute of Optoelectronics, MUT, comprises two integrated extended blackbodies with the following specifications: area 200×200 mm, stabilized absolute temperature range +15 °C÷100 °C, and uniformity of temperature distribution across entire surface +/-0.014 °C. Test stand, method used for the measurement of NUC coefficients and the results obtained during the measurements conducted on a prototype thermal camera will be presented in the paper.

  15. Optimal design of Anger camera for bremsstrahlung imaging: Monte Carlo evaluation.

    Directory of Open Access Journals (Sweden)

    Stephan eWalrand

    2014-06-01

    Full Text Available A conventional Anger camera is not adapted to bremsstrahlung imaging and, as a result, even using a reduced energy acquisition window, geometric x-rays represent less than 15% of the recorded events. This increases noise, limits the contrast, and reduces the quantification accuracy.Monte Carlo simulations of energy spectra showed that a camera based on a 30mm-thick BGO crystal and equipped with a high energy pinhole collimator is well adapted to bremsstrahlung imaging. The total scatter contamination is reduced by a factor ten versus a conventional NaI camera equipped with a high energy parallel hole collimator enabling acquisition using an extended energy window ranging from 50 to 350 keV. By using the recorded event energy in the reconstruction method, shorter acquisition time and reduced orbit range will be usable allowing the design of a simplified mobile gantry. This is more convenient for use in a busy catheterization room. After injecting a safe activity, a fast SPECT could be performed without moving the catheter tip in order to assess the liver dosimetry and estimate the additional safe activity that could still be injected.Further long running time Monte Carlo simulations of realistic acquisitions will allow assessing the quantification capability of such system. Simultaneously, a dedicated bremsstrahlung prototype camera reusing PMT-BGO blocks coming from a retired PET system is currently under design for further evaluation.

  16. Development of a compact scintillator-based high-resolution Compton camera for molecular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, A., E-mail: daphne3h-aya@ruri.waseda.jp [Research Institute for Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku, Tokyo (Japan); Kataoka, J.; Koide, A.; Sueoka, K.; Iwamoto, Y.; Taya, T. [Research Institute for Science and Engineering, Waseda University, 3-4-1 Ohkubo, Shinjuku, Tokyo (Japan); Ohsuka, S. [Central Research Laboratory, Hamamatsu Photonics K.K., 5000 Hirakuchi, Hamakita-ku, Hamamatsu, Shizuoka (Japan)

    2017-02-11

    The Compton camera, which shows gamma-ray distribution utilizing the kinematics of Compton scattering, is a promising detector capable of imaging across a wide range of energy. In this study, we aim to construct a small-animal molecular imaging system in a wide energy range by using the Compton camera. We developed a compact medical Compton camera based on a Ce-doped Gd{sub 3}Al{sub 2}Ga{sub 3}O{sub 12} (Ce:GAGG) scintillator and multi-pixel photon counter (MPPC). A basic performance confirmed that for 662 keV, the typical energy resolution was 7.4 % (FWHM) and the angular resolution was 4.5° (FWHM). We then used the medical Compton camera to conduct imaging experiments based on a 3-D imaging reconstruction algorithm using the multi-angle data acquisition method. The result confirmed that for a {sup 137}Cs point source at a distance of 4 cm, the image had a spatial resolution of 3.1 mm (FWHM). Furthermore, we succeeded in producing 3-D multi-color image of different simultaneous energy sources ({sup 22}Na [511 keV], {sup 137}Cs [662 keV], and {sup 54}Mn [834 keV]).

  17. Camera Development for the Cherenkov Telescope Array

    Science.gov (United States)

    Moncada, Roberto Jose

    2017-01-01

    With the Cherenkov Telescope Array (CTA), the very-high-energy gamma-ray universe, between 30 GeV and 300 TeV, will be probed at an unprecedented resolution, allowing deeper studies of known gamma-ray emitters and the possible discovery of new ones. This exciting project could also confirm the particle nature of dark matter by looking for the gamma rays produced by self-annihilating weakly interacting massive particles (WIMPs). The telescopes will use the imaging atmospheric Cherenkov technique (IACT) to record Cherenkov photons that are produced by the gamma-ray induced extensive air shower. One telescope design features dual-mirror Schwarzschild-Couder (SC) optics that allows the light to be finely focused on the high-resolution silicon photomultipliers of the camera modules starting from a 9.5-meter primary mirror. Each camera module will consist of a focal plane module and front-end electronics, and will have four TeV Array Readout with GSa/s Sampling and Event Trigger (TARGET) chips, giving them 64 parallel input channels. The TARGET chip has a self-trigger functionality for readout that can be used in higher logic across camera modules as well as across individual telescopes, which will each have 177 camera modules. There will be two sites, one in the northern and the other in the southern hemisphere, for full sky coverage, each spanning at least one square kilometer. A prototype SC telescope is currently under construction at the Fred Lawrence Whipple Observatory in Arizona. This work was supported by the National Science Foundation's REU program through NSF award AST-1560016.

  18. A Study towards Real Time Camera Calibration

    OpenAIRE

    Choudhury, Ragini

    2000-01-01

    Preliminary Report Prepared for the Project VISTEO; This report provides a detailed study of the problem of real time camera calibration. This analysis, based on the study of literature in the area, as well as the experiments carried out on real and synthetic data, is motivated by the requirements of the VISTEO project. VISTEO deals with a fusion of real images and synthetic environments, objects etc in TV video sequences. It thus deals with a challenging and fast growing area in virtual real...

  19. Combining local and global optimisation for virtual camera control

    OpenAIRE

    Burelli, Paolo; Yannakakis, Georgios N.; 2010 IEEE Symposium on Computational Intelligence and Games

    2010-01-01

    Controlling a virtual camera in 3D computer games is a complex task. The camera is required to react to dynamically changing environments and produce high quality visual results and smooth animations. This paper proposes an approach that combines local and global search to solve the virtual camera control problem. The automatic camera control problem is described and it is decomposed into sub-problems; then a hierarchical architecture that solves each sub-problem using the most appropriate op...

  20. CEBAF Upgrade Bunch Length Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahmoud [Old Dominion Univ., Norfolk, VA (United States)

    2016-05-01

    Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes without modifying the old procedures. Two of them can be used when the beam is not compressed longitudinally while the other one, the synchrotron light monitor, can be used with compressed or uncompressed beam.

  1. Continuously variable focal length lens

    Science.gov (United States)

    Adams, Bernhard W; Chollet, Matthieu C

    2013-12-17

    A material preferably in crystal form having a low atomic number such as beryllium (Z=4) provides for the focusing of x-rays in a continuously variable manner. The material is provided with plural spaced curvilinear, optically matched slots and/or recesses through which an x-ray beam is directed. The focal length of the material may be decreased or increased by increasing or decreasing, respectively, the number of slots (or recesses) through which the x-ray beam is directed, while fine tuning of the focal length is accomplished by rotation of the material so as to change the path length of the x-ray beam through the aligned cylindrical slows. X-ray analysis of a fixed point in a solid material may be performed by scanning the energy of the x-ray beam while rotating the material to maintain the beam's focal point at a fixed point in the specimen undergoing analysis.

  2. A didactic experiment showing the Compton scattering by means of a clinical gamma camera.

    Science.gov (United States)

    Amato, Ernesto; Auditore, Lucrezia; Campennì, Alfredo; Minutoli, Fabio; Cucinotta, Mariapaola; Sindoni, Alessandro; Baldari, Sergio

    2017-06-01

    We describe a didactic approach aimed to explain the effect of Compton scattering in nuclear medicine imaging, exploiting the comparison of a didactic experiment with a gamma camera with the outcomes from a Monte Carlo simulation of the same experimental apparatus. We employed a 99m Tc source emitting 140.5keV photons, collimated in the upper direction through two pinholes, shielded by 6mm of lead. An aluminium cylinder was placed on the source at 50mm of distance. The energy of the scattered photons was measured on the spectra acquired by the gamma camera. We observed that the gamma ray energy measured at each step of rotation gradually decreased from the characteristic energy of 140.5keV at 0° to 102.5keV at 120°. A comparison between the obtained data and the expected results from the Compton formula and from the Monte Carlo simulation revealed a full agreement within the experimental error (relative errors between -0.56% and 1.19%), given by the energy resolution of the gamma camera. Also the electron rest mass has been evaluated satisfactorily. The experiment was found useful in explaining nuclear medicine residents the phenomenology of the Compton scattering and its importance in the nuclear medicine imaging, and it can be profitably proposed during the training of medical physics residents as well. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  3. The AOTF-Based NO2 Camera

    Science.gov (United States)

    Dekemper, E.; Fussen, D.; Vanhellemont, F.; Vanhamel, J.; Pieroux, D.; Berkenbosch, S.

    2017-12-01

    In an urban environment, nitrogen dioxide is emitted by a multitude of static and moving point sources (cars, industry, power plants, heating systems,…). Air quality models generally rely on a limited number of monitoring stations which do not capture the whole pattern, neither allow for full validation. So far, there has been a lack of instrument capable of measuring NO2 fields with the necessary spatio-temporal resolution above major point sources (power plants), or more extended ones (cities). We have developed a new type of passive remote sensing instrument aiming at the measurement of 2-D distributions of NO2 slant column densities (SCDs) with a high spatial (meters) and temporal (minutes) resolution. The measurement principle has some similarities with the popular filter-based SO2 camera (used in volcanic and industrial sulfur emissions monitoring) as it relies on spectral images taken at wavelengths where the molecule absorption cross section is different. But contrary to the SO2 camera, the spectral selection is performed by an acousto-optical tunable filter (AOTF) capable of resolving the target molecule's spectral features. A first prototype was successfully tested with the plume of a coal-firing power plant in Romania, revealing the dynamics of the formation of NO2 in the early plume. A lighter version of the NO2 camera is now being tested on other targets, such as oil refineries and urban air masses.

  4. Robust automatic camera pointing for airborne surveillance

    Science.gov (United States)

    Dwyer, David; Wren, Lee; Thornton, John; Bonsor, Nigel

    2002-08-01

    Airborne electro-optic surveillance from a moving platform currently requires regular interaction from a trained operator. Even simple tasks such as fixating on a static point on the ground can demand constant adjustment of the camera orientation to compensate for platform motion. In order to free up operator time for other tasks such as navigation and communication with ground assets, an automatic gaze control system is needed. This paper describes such a system, based purely on tracking points within the video image. A number of scene points are automatically selected and their inter-frame motion tracked. The scene motion is then estimated using a model of a planar projective transform. For reliable and accurate camera pointing, the modeling of the scene motion must be robust to common problems such as scene point obscuration, objects moving independently within the scene and image noise. This paper details a COTS based system for automatic camera fixation and describes ways of preventing objects moving in the scene or poor motion estimates from corrupting the scene motion model.

  5. Enhancing image quality produced by IR cameras

    Science.gov (United States)

    Dulski, R.; Powalisz, P.; Kastek, M.; Trzaskawka, P.

    2010-10-01

    Images produced by IR cameras are a specific source of information. The perception and interpretation of such image greatly depends on thermal properties of observed object and surrounding scenery. In practice, the optimal settings of the camera as well as automatic temperature range control do not guarantee the displayed images is optimal from observer's point of view. The solution to this could be the methods and algorithms of digital image processing implemented in the camera. Such solution should provide intelligent, dynamic contrast control applied not only across entire image but also selectively to specific areas in order to maintain optimal visualization of observed scenery. The paper discusses problems dealing with improvement of the visibility of low-contrast objects and presents method of image enhancement. The algorithm is based on adaptive histogram equalization. The image enhancement algorithm was tested on real IR images. The algorithm significantly improves the image quality and the effectiveness of object detection for the majority of thermal images. Due to its adaptive nature it should be effective for any given thermal image. The application of such algorithm is promising alternative to more expensive opto-electronic components like improved optics and detectors.

  6. Theory and applications of smart cameras

    CERN Document Server

    2016-01-01

    This book presents an overview of smart camera systems, considering practical applications but also reviewing fundamental aspects of the underlying technology.  It introduces in a tutorial style the principles of sensing and signal processing, and also describes topics such as wireless connection to the Internet of Things (IoT) which is expected to be the biggest market for smart cameras. It is an excellent guide to the fundamental of smart camera technology, and the chapters complement each other well as the authors have worked as a team under the auspice of GFP(Global Frontier Project), the largest-scale funded research in Korea.  This is the third of three books based on the Integrated Smart Sensors research project, which describe the development of innovative devices, circuits, and system-level enabling technologies.  The aim of the project was to develop common platforms on which various devices and sensors can be loaded, and to create systems offering significant improvements in information processi...

  7. Design of POSICAM: A high resolution multislice whole body positron camera

    International Nuclear Information System (INIS)

    Mullani, N.A.; Wong, W.H.; Hartz, R.K.; Bristow, D.; Gaeta, J.M.; Yerian, K.; Adler, S.; Gould, K.L.

    1985-01-01

    A high resolution (6mm), multislice (21) whole body positron camera has been designed with innovative detector and septa arrangement for 3-D imaging and tracer quantitation. An object of interest such as the brain and the heart is optimally imaged by the 21 simultaneous image planes which have 12 mm resolution and are separated by 5.5 mm to provide adequate sampling in the axial direction. The detector geometry and the electronics are flexible enough to allow BaF 2 , BGO, GSO or time of flight BaF 2 scintillators. The mechanical gantry has been designed for clinical applications and incorporates several features for patient handling and comfort. A large patient opening of 58 cm diameter with a tilt of +-30 0 and rotation of +-20 0 permit imaging from different positions without moving the patient. Multiprocessor computing systems and user-friendly software make the POSICAM a powerful 3-D imaging device. 7 figs

  8. Overview of bunch length measurements

    International Nuclear Information System (INIS)

    Lumpkin, A. H.

    1999-01-01

    An overview of particle and photon beam bunch length measurements is presented in the context of free-electron laser (FEL) challenges. Particle-beam peak current is a critical factor in obtaining adequate FEL gain for both oscillators and self-amplified spontaneous emission (SASE) devices. Since measurement of charge is a standard measurement, the bunch length becomes the key issue for ultrashort bunches. Both time-domain and frequency-domain techniques are presented in the context of using electromagnetic radiation over eight orders of magnitude in wavelength. In addition, the measurement of microbunching in a micropulse is addressed

  9. Kondo length in bosonic lattices

    Science.gov (United States)

    Giuliano, Domenico; Sodano, Pasquale; Trombettoni, Andrea

    2017-09-01

    Motivated by the fact that the low-energy properties of the Kondo model can be effectively simulated in spin chains, we study the realization of the effect with bond impurities in ultracold bosonic lattices at half filling. After presenting a discussion of the effective theory and of the mapping of the bosonic chain onto a lattice spin Hamiltonian, we provide estimates for the Kondo length as a function of the parameters of the bosonic model. We point out that the Kondo length can be extracted from the integrated real-space correlation functions, which are experimentally accessible quantities in experiments with cold atoms.

  10. IMPLEMENTATION OF ZOOM-DEPENDENT CAMERA CALIBRATION IN CLOSE-RANGE PHOTOGRAMMETRY

    Directory of Open Access Journals (Sweden)

    C. S. Fraser

    2012-07-01

    Full Text Available The application of consumer-grade cameras for photogrammetric measurement has traditionally been subject to the requirement that imagery is recorded at fixed zoom and focus settings. The camera is then metrically calibrated, usually via self-calibration, for the lens setting employed. This requirement arises since camera parameters, and especially principal distance and lens distortion coefficients, vary significantly with zoom/focus setting. A recently developed process, titled zoom-dependent (Z-D calibration, removes the necessity for the zoom setting to be fixed during the image capture process. Implementation of Z-D calibration requires that the camera be pre-calibrated at four or more focal settings within the zoom range, nominally at shortest and longest focal lengths, and at two mid-zoom settings. This requirement, coupled with issues of data management in carrying different focal settings for potentially every image within a bundle adjustment, has largely accounted for the reason that Z-D calibration has not previously been implemented within COTS software for close-range photogrammetry. The objective of this paper is to describe the practical implementation of Z-D calibration within software, along with its associated workflow, and to discuss issues that impact upon the accuracy, reliability and appropriateness of the technique. Experimental testing is used to highlight the merits and shortcomings of ZD calibration.

  11. The evaluation on clamping force of high strength bolts by length parameter

    International Nuclear Information System (INIS)

    Kim, Kang-Seok; Nah, Hwan-Seon; Lee, Hyeon-Ju; Lee, Kang-Min

    2009-01-01

    It has been reported that the length parameter of high strength bolts results in the variance in tension loads. The required turn for each length is specified in AISC RCSC specification. This study was focused on evaluating any influence on the clamping torque subjected to length parameter of high strength bolts. The two kinds of high strength bolts of specimen are as follows; High Strength Hexagon bolt defined on ASTM A490 and Torque Shear Bolt on KS B 2819. The length parameter ranged from 60mm(3d) to 140mm(7d). The torque, turn of nut and the clamping force were analyzed to review whether length parameter can be affected on the required tension load. To test whether the length parameter has an impact on the torque and turn of nut for the required strength and clamping force, statistical analysis is carried out. (author)

  12. CCD characterization for a range of color cameras

    NARCIS (Netherlands)

    Withagen, P.J.; Groen, F.C.A.; Schutte, K.

    2005-01-01

    CCD cameras are widely used for remote sensing and image processing applications. However, most cameras are produced to create nice images, not to do accurate measurements. Post processing operations such as gamma adjustment and automatic gain control are incorporated in the camera. When a (CCD)

  13. A generic model for camera based intelligent road crowd control ...

    African Journals Online (AJOL)

    This research proposes a model for intelligent traffic flow control by implementing camera based surveillance and feedback system. A series of cameras are set minimum three signals ahead from the target junction. The complete software system is developed to help integrating the multiple camera on road as feedback to ...

  14. MISR L1B3 Radiometric Camera-by-camera Cloud Mask Product subset for the RICO region V004

    Data.gov (United States)

    National Aeronautics and Space Administration — This file contains the Radiometric camera-by-camera Cloud Mask dataset over the RICO region. It is used to determine whether a scene is classified as clear or...

  15. Axial Lengths in Children with Recessive Cornea Plana.

    Science.gov (United States)

    Al Hazimi, Amro; Khan, Arif O

    2015-06-01

    While flat keratometry contributes to the hyperopia and associated refractive accommodative esotropia that is part of recessive cornea plana, whether or not axial lengths are abnormally short in the disease is unclear. In this study we assess this possibility. Prospective (2010-2012) axial length measurement (IOLmaster; Carl Zeiss, Oberkochen, Germany) of affected right eyes and comparison to right eyes with refractive accommodative esotropia only. Keratometry and refraction were also performed. For eight affected right eyes (age 10-12 years; seven families) axial length ranged from 21.46-24.80 mm (mean 23.34). Best corrected visual acuity ranged from 20/25 to 20/50, keratometry from 25.33-39.80 diopters (D) [mean 31.80], and refraction from +2.00 to +14.00 D (mean +7.22). For 50 control right eyes (age 4-12 years), axial length ranged from 19.87-23.66 mm (mean 21.6). Best-corrected visual acuity was 20/25 or better, keratometry ranged from 39.81-46.25 D (mean 42.42), and refraction from +2.25 to +8.00 D (mean 4.71). Axial lengths were longer in the affected group (2-tailed unpaired t-test p value 0.000005) despite greater hyperopia (2-tailed unpaired t-test p value 0.001). Despite greater hyperopia, axial lengths were longer in eyes with recessive cornea plana, evidence that axial lengths are not shortened by the disease. Keratometry in children with cornea plana was below the range of controls and was the major factor underlying the phenotype's hyperopia.

  16. A 300-nm compact mm-wave linac FEL design

    Energy Technology Data Exchange (ETDEWEB)

    Nassiri, A.; Kustom, R.L.; Kang, Y.W. [Argonne National Lab., IL (United States)

    1995-12-31

    Microfabrication technology offers an alternative method for fabricating precision, miniature-size components suitable for use in accelerator physics and commercial applications. The original R&D work at Argonne, in collaboration with the University of Illinois at Chicago, has produced encouraging results in the area of rf accelerating structure design, optical and x-ray masks production, deep x-ray lithography (LIGA exposures), and precision structural alignments. In this paper we will present a design study for a compact single pass mm-linac FEL to produce short wavelength radiation. This system will consists of a photocathode rf gun operated at 30 GHz, a 50-MeV superconducting constant gradient structure operated at 60 GHz, and a microundulator with 1-mm period. Initial experimental results on a scale model rf gun and microundulator will be presented.

  17. Introduction to statistics using interactive MM*Stat elements

    CERN Document Server

    Härdle, Wolfgang Karl; Rönz, Bernd

    2015-01-01

    MM*Stat, together with its enhanced online version with interactive examples, offers a flexible tool that facilitates the teaching of basic statistics. It covers all the topics found in introductory descriptive statistics courses, including simple linear regression and time series analysis, the fundamentals of inferential statistics (probability theory, random sampling and estimation theory), and inferential statistics itself (confidence intervals, testing). MM*Stat is also designed to help students rework class material independently and to promote comprehension with the help of additional examples. Each chapter starts with the necessary theoretical background, which is followed by a variety of examples. The core examples are based on the content of the respective chapter, while the advanced examples, designed to deepen students’ knowledge, also draw on information and material from previous chapters. The enhanced online version helps students grasp the complexity and the practical relevance of statistical...

  18. 9th IFToMM International Conference on Rotor Dynamics

    CERN Document Server

    2015-01-01

    This book presents the proceedings of the 9th IFToMM International Conference on Rotor Dynamics. This conference is a premier global event that brings together specialists from the university and industry sectors worldwide in order to promote the exchange of knowledge, ideas, and information on the latest developments and applied technologies in the dynamics of rotating machinery. The coverage is wide ranging, including, for example, new ideas and trends in various aspects of bearing technologies, issues in the analysis of blade dynamic behavior,  condition monitoring of different rotating machines, vibration control, electromechanical and fluid-structure interactions in rotating machinery, rotor dynamics of micro, nano, and cryogenic machines, and applications of rotor dynamics in transportation engineering. Since its inception 32 years ago, the IFToMM International Conference on Rotor Dynamics has become an irreplaceable point of reference for those working in the field, and this book reflects the high qua...

  19. Udtrækning af 10 mm ankerbolte

    DEFF Research Database (Denmark)

    Hansen, Lars Pilegaard

    Denne rapport beskriver forsøg med udtrækning af 10 mm ankerbolte udført af Laboratoriet for Bærende Konstruktioner, Instituttet for Bygningsteknik, Aalborg Universitet. Forsøgene blev udført d. 19. og 21. juni 2001. Forsøgene blev udført dels på Hjørring Sygehus og dels på Laboratoriet.......Denne rapport beskriver forsøg med udtrækning af 10 mm ankerbolte udført af Laboratoriet for Bærende Konstruktioner, Instituttet for Bygningsteknik, Aalborg Universitet. Forsøgene blev udført d. 19. og 21. juni 2001. Forsøgene blev udført dels på Hjørring Sygehus og dels på Laboratoriet....

  20. Modeling and simulation of gamma camera

    International Nuclear Information System (INIS)

    Singh, B.; Kataria, S.K.; Samuel, A.M.

    2002-08-01

    Simulation techniques play a vital role in designing of sophisticated instruments and also for the training of operating and maintenance staff. Gamma camera systems have been used for functional imaging in nuclear medicine. Functional images are derived from the external counting of the gamma emitting radioactive tracer that after introduction in to the body mimics the behavior of native biochemical compound. The position sensitive detector yield the coordinates of the gamma ray interaction with the detector and are used to estimate the point of gamma ray emission within the tracer distribution space. This advanced imaging device is thus dependent on the performance of algorithm for coordinate computing, estimation of point of emission, generation of image and display of the image data. Contemporary systems also have protocols for quality control and clinical evaluation of imaging studies. Simulation of this processing leads to understanding of the basic camera design problems. This report describes a PC based package for design and simulation of gamma camera along with the options of simulating data acquisition and quality control of imaging studies. Image display and data processing the other options implemented in SIMCAM will be described in separate reports (under preparation). Gamma camera modeling and simulation in SIMCAM has preset configuration of the design parameters for various sizes of crystal detector with the option to pack the PMT on hexagon or square lattice. Different algorithm for computation of coordinates and spatial distortion removal are allowed in addition to the simulation of energy correction circuit. The user can simulate different static, dynamic, MUGA and SPECT studies. The acquired/ simulated data is processed for quality control and clinical evaluation of the imaging studies. Results show that the program can be used to assess these performances. Also the variations in performance parameters can be assessed due to the induced