WorldWideScience

Sample records for online epid verification

  1. WE-D-BRA-04: Online 3D EPID-Based Dose Verification for Optimum Patient Safety

    Energy Technology Data Exchange (ETDEWEB)

    Spreeuw, H; Rozendaal, R; Olaciregui-Ruiz, I; Mans, A; Mijnheer, B; Herk, M van; Gonzalez, P [Netherlands Cancer Institute - Antoni van Leeuwenhoek, Amsterdam, Noord-Holland (Netherlands)

    2015-06-15

    Purpose: To develop an online 3D dose verification tool based on EPID transit dosimetry to ensure optimum patient safety in radiotherapy treatments. Methods: A new software package was developed which processes EPID portal images online using a back-projection algorithm for the 3D dose reconstruction. The package processes portal images faster than the acquisition rate of the portal imager (∼ 2.5 fps). After a portal image is acquired, the software seeks for “hot spots” in the reconstructed 3D dose distribution. A hot spot is in this study defined as a 4 cm{sup 3} cube where the average cumulative reconstructed dose exceeds the average total planned dose by at least 20% and 50 cGy. If a hot spot is detected, an alert is generated resulting in a linac halt. The software has been tested by irradiating an Alderson phantom after introducing various types of serious delivery errors. Results: In our first experiment the Alderson phantom was irradiated with two arcs from a 6 MV VMAT H&N treatment having a large leaf position error or a large monitor unit error. For both arcs and both errors the linac was halted before dose delivery was completed. When no error was introduced, the linac was not halted. The complete processing of a single portal frame, including hot spot detection, takes about 220 ms on a dual hexacore Intel Xeon 25 X5650 CPU at 2.66 GHz. Conclusion: A prototype online 3D dose verification tool using portal imaging has been developed and successfully tested for various kinds of gross delivery errors. The detection of hot spots was proven to be effective for the timely detection of these errors. Current work is focused on hot spot detection criteria for various treatment sites and the introduction of a clinical pilot program with online verification of hypo-fractionated (lung) treatments.

  2. Creation of a Reference Image with Monte Carlo Simulations for Online EPID Verification of Daily Patient Setup

    Energy Technology Data Exchange (ETDEWEB)

    Descalle, M-A; Chuang, C; Pouliot, J

    2002-01-30

    Patient positioning accuracy remains an issue for external beam radiotherapy. Currently, kilovoltage verification images are used as reference by clinicians to compare the actual patient treatment position with the planned position. These images are qualitatively different from treatment-time megavoltage portal images. This study will investigate the feasibility of using PEREGRINE, a 3D Monte Carlo calculation engine, to create reference images for portal image comparisons. Portal images were acquired using an amorphous-silicon flat-panel EPID for (1) the head and pelvic sections of an anthropomorphic phantom with 7-8 mm displacements applied, and (2) a prostate patient on five treatment days. Planning CT scans were used to generate simulated reference images with PEREGRINE. A correlation algorithm quantified the setup deviations between simulated and portal images. Monte Carlo simulated images exhibit similar qualities to portal images, the phantom slabs appear clearly. Initial positioning differences and applied displacements were detected and quantified. We find that images simulated with Monte Carlo methods can be used as reference images to detect and quantify set-up errors during treatment.

  3. Simplifying EPID dosimetry for IMRT treatment verification

    Energy Technology Data Exchange (ETDEWEB)

    Pecharroman-Gallego, R.; Mans, Anton; Sonke, Jan-Jakob; Stroom, Joep C.; Olaciregui-Ruiz, Igor; Herk, Marcel van; Mijnheer, Ben J. [Department of Radiation Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands)

    2011-02-15

    Purpose: Electronic portal imaging devices (EPIDs) are increasingly used for IMRT dose verification, both pretreatment and in vivo. In this study, an earlier developed backprojection model has been modified to avoid the need for patient-specific transmission measurements and, consequently, leads to a faster procedure. Methods: Currently, the transmission, an essential ingredient of the backprojection model, is estimated from the ratio of EPID measurements with and without a phantom/patient in the beam. Thus, an additional irradiation to obtain ''open images'' under the same conditions as the actual phantom/patient irradiation is required. However, by calculating the transmission of the phantom/patient in the direction of the beam instead of using open images, this extra measurement can be avoided. This was achieved by using a model that includes the effect of beam hardening and off-axis dependence of the EPID response on photon beam spectral changes. The parameters in the model were empirically obtained by performing EPID measurements using polystyrene slab phantoms of different thickness in 6, 10, and 18 MV photon beams. A theoretical analysis to verify the sensitivity of the model with patient thickness changes was performed. The new model was finally applied for the analysis of EPID dose verification measurements of step-and-shoot IMRT treatments of head and neck, lung, breast, cervix, prostate, and rectum patients. All measurements were carried out using Elekta SL20i linear accelerators equipped with a hydrogenated amorphous silicon EPID, and the IMRT plans were made using PINNACLE software (Philips Medical Systems). Results: The results showed generally good agreement with the dose determined using the old model applying the measured transmission. The average differences between EPID-based in vivo dose at the isocenter determined using either the new model for transmission and its measured value were 2.6{+-}3.1%, 0.2{+-}3.1%, and 2

  4. Accurate two-dimensional IMRT verification using a back-projection EPID dosimetry method.

    NARCIS (Netherlands)

    Wendling, M.; Louwe, R.J.W.; McDermott, L.N.; Sonke, J.J.; Herk, M. van; Mijnheer, B.J.

    2006-01-01

    The use of electronic portal imaging devices (EPIDs) is a promising method for the dosimetric verification of external beam, megavoltage radiation therapy-both pretreatment and in vivo. In this study, a previously developed EPID back-projection algorithm was modified for IMRT techniques and applied

  5. Characterization of a novel EPID designed for simultaneous imaging and dose verification in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Blake, Samuel J.; McNamara, Aimee L. [Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006, Australia and Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); Deshpande, Shrikant [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres, NSW 2170 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); Holloway, Lois [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres, NSW 2170 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522 (Australia); South Western Sydney Clinical School, University of New South Wales, Sydney, NSW 2170 (Australia); Greer, Peter B. [Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Newcastle, NSW 2298, Australia and School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, NSW 2308 (Australia); Kuncic, Zdenka [Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Vial, Philip [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres, NSW 2170 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia)

    2013-09-15

    of 1–100 monitor units. Over this range, the prototype and standard EPID central axis responses agreed to within 1.6%. Images taken with the prototype EPID were noisier than those taken with the standard EPID, with fractional uncertainties of 0.2% and 0.05% within the central 1 cm{sup 2}, respectively. For all dosimetry measurements, the prototype EPID exhibited a near water-equivalent response whereas the standard EPID did not. The CNR and spatial resolution of images taken with the standard EPID were greater than those taken with the prototype EPID.Conclusions: A prototype EPID employing an array of PS fibers has been developed and the first experimental measurements are reported. The prototype EPID demonstrated a much morewater-equivalent dose response than the standard EPID. While the imaging performance of the standard EPID was superior to that of the prototype, the prototype EPID has many design characteristics that may be optimized to improve imaging performance. This investigation demonstrates the feasibility of a new detector design for simultaneous imaging and dosimetry treatment verification in radiotherapy.

  6. Gantry-angle resolved VMAT pretreatment verification using EPID image prediction

    Energy Technology Data Exchange (ETDEWEB)

    Woodruff, Henry C.; Rowshanfarzad, Pejman [School of Mathematical and Physical Sciences, The University of Newcastle, NSW 2308 (Australia); Fuangrod, Todsaporn [School of Electrical Engineering and Computer Science, The University of Newcastle, NSW 2308 (Australia); McCurdy, Boyd M. C. [Division of Medical Physics, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Department of Radiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Greer, Peter B. [School of Mathematical and Physical Sciences, The University of Newcastle, NSW 2308, Australia and Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Locked Bag 7, Hunter region Mail Centre, Newcastle, NSW 2310 (Australia)

    2013-08-15

    Purpose: Pretreatment verification of volumetric modulated arc therapy (VMAT) dose delivery with electronic portal imaging device (EPID) uses images integrated over the entire delivery or over large subarcs. This work aims to develop a new method for gantry-angle-resolved verification of VMAT dose delivery using EPID.Methods: An EPID dose prediction model was used to calculate EPID images as a function of gantry angle for eight prostate patient deliveries. EPID image frames at 7.5 frames per second were acquired during delivery via a frame-grabber system. The gantry angle for each image was encoded in kV frames which were synchronized to the MV frames. Gamma analysis results as a function of gantry angle were assessed by integrating the frames over 2° subarcs with an angle-to-agreement tolerance of 0.5° about the measured image angle.Results: The model agreed with EPID images integrated over the entire delivery with average Gamma pass-rates at 2%, 2 mm of 99.7% (10% threshold). The accuracy of the kV derived gantry angle for each image was found to be 0.1° (1 SD) using a phantom test. For the gantry-resolved analysis all Gamma pass-rates were greater than 90% at 3%, 3 mm criteria (with only two exceptions), and more than 90% had a 95% pass-rate, with an average of 97.3%. The measured gantry angle lagged behind the predicted angle by a mean of 0.3°± 0.3°, with a maximum lag of 1.3°.Conclusions: The method provides a comprehensive and highly efficient pretreatment verification of VMAT delivery using EPID. Dose delivery accuracy is assessed as a function of gantry angle to ensure accurate treatment.

  7. Dosimetric properties of an amorphous silicon EPID for verification of modulated electron radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chatelain, Cecile; Vetterli, Daniel; Henzen, Dominik; Favre, Pascal; Fix, Michael K.; Manser, Peter [Division of Medical Radiation Physics and Department of Radiation Oncology, Inselspital, Bern University Hospital and University of Bern, Bern CH-3010 (Switzerland); Morf, Daniel; Scheib, Stefan [Varian Medical Systems Imaging Laboratories GmbH, Baden-Daettwil CH-5405 (Switzerland)

    2013-06-15

    measurements, the gamma pass rate (criteria: 2%, 2 mm) was better than 97% for all the tested cases. Conclusions: This study demonstrates the high potential of the EPID for electron dosimetry, and in particular, confirms the possibility to use it as an efficient verification tool for MERT delivery.

  8. Dose verifications by use of liquid ionization chamber of an electronic portal imaging device (EPID).

    Science.gov (United States)

    Tateoka, Kunihiko; Oouchi, Atsushi; Nakata, Kensei; Hareyama, Masato

    2008-07-01

    In this study, we examined the ability of an L-EPID to verify rectangular and irregular fields and to measure the transmitted exit doses. With respect to the beam profile of rectangular and irregular fields and the doses transmitted through an inhomogeneous phantom, the L-EPID dose obtained from the L-EPID measurement was compared with the conventional dose measured by use of a 0.12-cc ionization chamber and a 3D water phantom. In the comparison of the rectangular and irregular fields, the difference in the off-center ratio (OCR) between the L-EPID dose and the conventional dose was approximately 3% in the steep-dose-gradient region (penumbra regions, >30%/cm) and approximately +/-0.5% in the gentle-dose-gradient region (5%/cm). On the other hand, the dose differences between the L-EPID and the measured doses were less than approximately 2% in the gentle-dose-gradient region. In addition, in the steep-dose-gradient region, the maximum difference was 30%. However, the differences in the distance-to-agreement (DTA) were less than approximately +/-1 mm and were unrelated to the dose gradient. These results suggest that dose verification by L-EPID is very useful in clinical applications.

  9. 2D AND 3D dose verification at The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital using EPIDs

    Science.gov (United States)

    Mijnheer, Ben; Mans, Anton; Olaciregui-Ruiz, Igor; Sonke, Jan-Jakob; Tielenburg, Rene; Van Herk, Marcel; Vijlbrief, Ron; Stroom, Joep

    2010-11-01

    A review is given of the clinical use of EPID dosimetry in the Department of Radiation Oncology of The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital. All curative plans (almost all IMRT or VMAT) are verified with EPID dosimetry, mostly in vivo. The 2D approach for IMRT verification and the 3D method for VMAT verification are elucidated and their clinical implementation described. It has been shown that EPID dosimetry plays an important role in the total chain of verification procedures that are implemented in our department. It provides a safety net for advanced treatments such as IMRT and VMAT, as well as a full account of the dose delivered.

  10. Suitability of markerless EPID tracking for tumor position verification in gated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Serpa, Marco [Institute for Research and Development on Advanced Radiation Technologies (radART), Paracelsus Medical University, 5020 Salzburg (Austria); University Clinic for Radiotherapy and Radio-Oncology, Landeskrankenhaus Salzburg, Paracelsus Medical University Clinics, 5020 Salzburg (Austria); Department of Physics and Astronomy, University of Canterbury, Christchurch 8140 (New Zealand); Baier, Kurt; Guckenberger, Matthias [Department of Radiation Oncology, University of Wuerzburg, D-97080 Wuerzburg (Germany); Cremers, Florian [Department of Radiation Oncology, University Medical Center Hamburg Eppendorf, D-20246 Hamburg (Germany); Meyer, Juergen, E-mail: juergen@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195 (United States)

    2014-03-15

    Purpose: To maximize the benefits of respiratory gated radiotherapy (RGRT) of lung tumors real-time verification of the tumor position is required. This work investigates the feasibility of markerless tracking of lung tumors during beam-on time in electronic portal imaging device (EPID) images of the MV therapeutic beam. Methods: EPID movies were acquired at ∼2 fps for seven lung cancer patients with tumor peak-to-peak motion ranges between 7.8 and 17.9 mm (mean: 13.7 mm) undergoing stereotactic body radiotherapy. The external breathing motion of the abdomen was synchronously measured. Both datasets were retrospectively analyzed inPortalTrack, an in-house developed tracking software. The authors define a three-step procedure to run the simulations: (1) gating window definition, (2) gated-beam delivery simulation, and (3) tumor tracking. First, an amplitude threshold level was set on the external signal, defining the onset of beam-on/-off signals. This information was then mapped onto a sequence of EPID images to generate stamps of beam-on/-hold periods throughout the EPID movies in PortalTrack, by obscuring the frames corresponding to beam-off times. Last, tumor motion in the superior-inferior direction was determined on portal images by the tracking algorithm during beam-on time. The residual motion inside the gating window as well as target coverage (TC) and the marginal target displacement (MTD) were used as measures to quantify tumor position variability. Results: Tumor position monitoring and estimation from beam's-eye-view images during RGRT was possible in 67% of the analyzed beams. For a reference gating window of 5 mm, deviations ranging from 2% to 86% (35% on average) were recorded between the reference and measured residual motion. TC (range: 62%–93%; mean: 77%) losses were correlated with false positives incidence rates resulting mostly from intra-/inter-beam baseline drifts, as well as sudden cycle-to-cycle fluctuations in exhale positions

  11. A system for EPID-based real-time treatment delivery verification during dynamic IMRT treatment

    Energy Technology Data Exchange (ETDEWEB)

    Fuangrod, Todsaporn [Faculty of Engineering and Built Environment, School of Electrical Engineering and Computer Science, the University of Newcastle, NSW 2308 (Australia); Woodruff, Henry C.; O’Connor, Daryl J. [Faculty of Science and IT, School of Mathematical and Physical Sciences, the University of Newcastle, NSW 2308 (Australia); Uytven, Eric van; McCurdy, Boyd M. C. [Division of Medical Physics, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Department of Radiology, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Kuncic, Zdenka [School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Greer, Peter B. [Faculty of Science and IT, School of Mathematical and Physical Sciences, the University of Newcastle, NSW 2308, Australia and Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Locked Bag 7, Hunter region Mail Centre, Newcastle, NSW 2310 (Australia)

    2013-09-15

    Purpose: To design and develop a real-time electronic portal imaging device (EPID)-based delivery verification system for dynamic intensity modulated radiation therapy (IMRT) which enables detection of gross treatment delivery errors before delivery of substantial radiation to the patient.Methods: The system utilizes a comprehensive physics-based model to generate a series of predicted transit EPID image frames as a reference dataset and compares these to measured EPID frames acquired during treatment. The two datasets are using MLC aperture comparison and cumulative signal checking techniques. The system operation in real-time was simulated offline using previously acquired images for 19 IMRT patient deliveries with both frame-by-frame comparison and cumulative frame comparison. Simulated error case studies were used to demonstrate the system sensitivity and performance.Results: The accuracy of the synchronization method was shown to agree within two control points which corresponds to approximately ∼1% of the total MU to be delivered for dynamic IMRT. The system achieved mean real-time gamma results for frame-by-frame analysis of 86.6% and 89.0% for 3%, 3 mm and 4%, 4 mm criteria, respectively, and 97.9% and 98.6% for cumulative gamma analysis. The system can detect a 10% MU error using 3%, 3 mm criteria within approximately 10 s. The EPID-based real-time delivery verification system successfully detected simulated gross errors introduced into patient plan deliveries in near real-time (within 0.1 s).Conclusions: A real-time radiation delivery verification system for dynamic IMRT has been demonstrated that is designed to prevent major mistreatments in modern radiation therapy.

  12. Epid Dosimetry

    Science.gov (United States)

    Greer, Peter B.; Vial, Philip

    2011-05-01

    Electronic portal imaging devices (EPIDs) were introduced originally for patient position verification. The idea of using EPIDs for dosimetry was realised in the 1980s. Little was published on the topic until the mid 1990's, when the interest in EPIDs for dosimetry increased rapidly and continues to grow. The increasing research on EPID dosimetry coincided with the introduction of intensity modulated radiation therapy (IMRT). EPIDs are well suited to IMRT dosimetry because they are high resolution, two-dimensional (2D) digital detectors. They are also pre-existing on almost all modern linear accelerators. They generally show a linear response to increasing dose. Different types of EPIDs have been clinically implemented, and these have been described in several review papers. The current generation of commercially available EPIDs are indirect detection active matrix flat panel imagers, also known as amorphous silicon (a-Si) EPIDs. Disadvantages of a-Si EPIDs for dosimetry include non-water equivalent construction materials, and the energy sensitivity and optical scatter of the phosphor scintillators used to create optical signal from the megavoltage beam. This report discusses current knowledge regarding a-Si EPIDs for dosimetry.

  13. An independent system for real-time dynamic multileaf collimation trajectory verification using EPID

    Science.gov (United States)

    Fuangrod, Todsaporn; Woodruff, Henry C.; Rowshanfarzad, Pejman; O'Connor, Daryl J.; Middleton, Richard H.; Greer, Peter B.

    2014-01-01

    A new tool has been developed to verify the trajectory of dynamic multileaf collimators (MLCs) used in advanced radiotherapy techniques using only the information provided by the electronic portal imaging devices (EPID) measured image frames. The prescribed leaf positions are resampled to a higher resolution in a pre-processing stage to improve the verification precision. Measured MLC positions are extracted from the EPID frames using a template matching method. A cosine similarity metric is then applied to synchronise measured and planned leaf positions for comparison. Three additional comparison functions were incorporated to ensure robust synchronisation. The MLC leaf trajectory error detection was simulated for both intensity modulated radiation therapy (IMRT) (prostate) and volumetric modulated arc therapy (VMAT) (head-and-neck) deliveries with anthropomorphic phantoms in the beam. The overall accuracy for MLC positions automatically extracted from EPID image frames was approximately 0.5 mm. The MLC leaf trajectory verification system can detect leaf position errors during IMRT and VMAT with a tolerance of 3.5 mm within 1 s.

  14. Online fingerprint verification.

    Science.gov (United States)

    Upendra, K; Singh, S; Kumar, V; Verma, H K

    2007-01-01

    As organizations search for more secure authentication methods for user access, e-commerce, and other security applications, biometrics is gaining increasing attention. With an increasing emphasis on the emerging automatic personal identification applications, fingerprint based identification is becoming more popular. The most widely used fingerprint representation is the minutiae based representation. The main drawback with this representation is that it does not utilize a significant component of the rich discriminatory information available in the fingerprints. Local ridge structures cannot be completely characterized by minutiae. Also, it is difficult quickly to match two fingerprint images containing different number of unregistered minutiae points. In this study filter bank based representation, which eliminates these weakness, is implemented and the overall performance of the developed system is tested. The results have shown that this system can be used effectively for secure online verification applications.

  15. Numident Online Verification Utility (NOVU)

    Data.gov (United States)

    Social Security Administration — NOVU is a mainframe application that accesses the NUMIDENT to perform real-time SSN verifications. This program is called by other SSA online programs that serve as...

  16. An in vivo dose verification method for SBRT–VMAT delivery using the EPID

    Energy Technology Data Exchange (ETDEWEB)

    McCowan, P. M., E-mail: peter.mccowan@cancercare.mb.ca [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Van Uytven, E.; Van Beek, T.; Asuni, G. [Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); McCurdy, B. M. C. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Radiology, University of Manitoba, 820 Sherbrook Street, Winnipeg, Manitoba R3A 1R9 (Canada)

    2015-12-15

    Purpose: Radiation treatments have become increasingly more complex with the development of volumetric modulated arc therapy (VMAT) and the use of stereotactic body radiation therapy (SBRT). SBRT involves the delivery of substantially larger doses over fewer fractions than conventional therapy. SBRT–VMAT treatments will strongly benefit from in vivo patient dose verification, as any errors in delivery can be more detrimental to the radiobiology of the patient as compared to conventional therapy. Electronic portal imaging devices (EPIDs) are available on most commercial linear accelerators (Linacs) and their documented use for dosimetry makes them valuable tools for patient dose verification. In this work, the authors customize and validate a physics-based model which utilizes on-treatment EPID images to reconstruct the 3D dose delivered to the patient during SBRT–VMAT delivery. Methods: The SBRT Linac head, including jaws, multileaf collimators, and flattening filter, were modeled using Monte Carlo methods and verified with measured data. The simulation provides energy spectrum data that are used by their “forward” model to then accurately predict fluence generated by a SBRT beam at a plane above the patient. This fluence is then transported through the patient and then the dose to the phosphor layer in the EPID is calculated. Their “inverse” model back-projects the EPID measured focal fluence to a plane upstream of the patient and recombines it with the extra-focal fluence predicted by the forward model. This estimate of total delivered fluence is then forward projected onto the patient’s density matrix and a collapsed cone convolution algorithm calculates the dose delivered to the patient. The model was tested by reconstructing the dose for two prostate, three lung, and two spine SBRT–VMAT treatment fractions delivered to an anthropomorphic phantom. It was further validated against actual patient data for a lung and spine SBRT–VMAT plan. The

  17. Verification of respiratory-gated radiotherapy with new real-time tumour-tracking radiotherapy system using cine EPID images and a log file

    Science.gov (United States)

    Shiinoki, Takehiro; Hanazawa, Hideki; Yuasa, Yuki; Fujimoto, Koya; Uehara, Takuya; Shibuya, Keiko

    2017-02-01

    A combined system comprising the TrueBeam linear accelerator and a new real-time tumour-tracking radiotherapy system, SyncTraX, was installed at our institution. The objectives of this study are to develop a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine electronic portal image device (EPID) images and a log file and to verify this treatment in clinical cases. Respiratory-gated radiotherapy was performed using TrueBeam and the SyncTraX system. Cine EPID images and a log file were acquired for a phantom and three patients during the course of the treatment. Digitally reconstructed radiographs (DRRs) were created for each treatment beam using a planning CT set. The cine EPID images, log file, and DRRs were analysed using a developed software. For the phantom case, the accuracy of the proposed method was evaluated to verify the respiratory-gated radiotherapy. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker used as an internal surrogate were calculated to evaluate the gating accuracy and set-up uncertainty in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions. The proposed method achieved high accuracy for the phantom verification. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker were  ⩽3 mm and  ±3 mm in the SI, AP, and LR directions. We proposed a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine EPID images and a log file and showed that this treatment is performed with high accuracy in clinical cases. This work was partly presented at the 58th Annual meeting of American Association of Physicists in Medicine.

  18. Verification of respiratory-gated radiotherapy with new real-time tumour-tracking radiotherapy system using cine EPID images and a log file.

    Science.gov (United States)

    Shiinoki, Takehiro; Hanazawa, Hideki; Yuasa, Yuki; Fujimoto, Koya; Uehara, Takuya; Shibuya, Keiko

    2017-02-21

    A combined system comprising the TrueBeam linear accelerator and a new real-time tumour-tracking radiotherapy system, SyncTraX, was installed at our institution. The objectives of this study are to develop a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine electronic portal image device (EPID) images and a log file and to verify this treatment in clinical cases. Respiratory-gated radiotherapy was performed using TrueBeam and the SyncTraX system. Cine EPID images and a log file were acquired for a phantom and three patients during the course of the treatment. Digitally reconstructed radiographs (DRRs) were created for each treatment beam using a planning CT set. The cine EPID images, log file, and DRRs were analysed using a developed software. For the phantom case, the accuracy of the proposed method was evaluated to verify the respiratory-gated radiotherapy. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker used as an internal surrogate were calculated to evaluate the gating accuracy and set-up uncertainty in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions. The proposed method achieved high accuracy for the phantom verification. For the clinical cases, the intra- and inter-fractional variations of the fiducial marker were  ⩽3 mm and  ±3 mm in the SI, AP, and LR directions. We proposed a method for the verification of respiratory-gated radiotherapy with SyncTraX using cine EPID images and a log file and showed that this treatment is performed with high accuracy in clinical cases.

  19. Verification of PTV margins for IMRT prostate cancer using EPID; Verificacao das margens de PTV para IMRT de cancer de prostata utilizando EPID

    Energy Technology Data Exchange (ETDEWEB)

    Leidens, Matheus; Santos, Romulo R.; Estacio, Daniela R. [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil). Hospital Sao Lucas. Servico de Fisica Medica; Silva, Ana Maria Marques da, E-mail: matheus_leidens@hotmail.com [Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Porto Alegre, RS (Brazil). Faculdade de Fisica

    2014-12-15

    The aim of this work is to present the results of a strategy to define the PTV margins for patients with prostate cancer treated with IMRT technique, due to geometrical uncertainties associated with the planned placement. 341 images of 31 patients in supine position, before applying the fractions, were obtained using an EPID attached to a linear accelerator, where only setup errors were studied. The displacements were analyzed in relation to the AP (antero-posterior), SI (superior-inferior) and LR (left-right) directions. The distribution pattern of systematic displacement deviation values were 0.12 cm, 0.06 cm, 0.02 cm and the standard deviation of the distribution of random deviations was 0.62 cm, 0.53 cm, and 0.24 cm in the AP, SI and LR directions, respectively. Data evaluation, according to Stroom and Heijmen’s method, suggests that PTV margins should be 0.66 cm in the AP direction, 0.49 cm in the SI direction and 0.20 cm in the LR direction. These data show a high reproducibility in the positioning of patients, given by a method for the correction of planned relative to the bony anatomy checked with the EPID position. (author)

  20. SU-E-T-490: Independent Three-Dimensional (3D) Dose Verification of VMAT/SBRT Using EPID and Cloud Computing

    Energy Technology Data Exchange (ETDEWEB)

    Ding, A; Han, B; Bush, K; Wang, L; Xing, L [Stanford University School of Medicine, Stanford, CA (United States)

    2015-06-15

    Purpose: Dosimetric verification of VMAT/SBRT is currently performed on one or two planes in a phantom with either film or array detectors. A robust and easy-to-use 3D dosimetric tool has been sought since the advent of conformal radiation therapy. Here we present such a strategy for independent 3D VMAT/SBRT plan verification system by a combined use of EPID and cloud-based Monte Carlo (MC) dose calculation. Methods: The 3D dosimetric verification proceeds in two steps. First, the plan was delivered with a high resolution portable EPID mounted on the gantry, and the EPID-captured gantry-angle-resolved VMAT/SBRT field images were converted into fluence by using the EPID pixel response function derived from MC simulations. The fluence was resampled and used as the input for an in-house developed Amazon cloud-based MC software to reconstruct the 3D dose distribution. The accuracy of the developed 3D dosimetric tool was assessed using a Delta4 phantom with various field sizes (square, circular, rectangular, and irregular MLC fields) and different patient cases. The method was applied to validate VMAT/SBRT plans using WFF and FFF photon beams (Varian TrueBeam STX). Results: It was found that the proposed method yielded results consistent with the Delta4 measurements. For points on the two detector planes, a good agreement within 1.5% were found for all the testing fields. Patient VMAT/SBRT plan studies revealed similar level of accuracy: an average γ-index passing rate of 99.2± 0.6% (3mm/3%), 97.4± 2.4% (2mm/2%), and 72.6± 8.4 % ( 1mm/1%). Conclusion: A valuable 3D dosimetric verification strategy has been developed for VMAT/SBRT plan validation. The technique provides a viable solution for a number of intractable dosimetry problems, such as small fields and plans with high dose gradient.

  1. A Hybrid On-line Verification Method of Relay Setting

    Science.gov (United States)

    Gao, Wangyuan; Chen, Qing; Si, Ji; Huang, Xin

    2017-05-01

    Along with the rapid development of the power industry, grid structure gets more sophisticated. The validity and rationality of protective relaying are vital to the security of power systems. To increase the security of power systems, it is essential to verify the setting values of relays online. Traditional verification methods mainly include the comparison of protection range and the comparison of calculated setting value. To realize on-line verification, the verifying speed is the key. The verifying result of comparing protection range is accurate, but the computation burden is heavy, and the verifying speed is slow. Comparing calculated setting value is much faster, but the verifying result is conservative and inaccurate. Taking the overcurrent protection as example, this paper analyses the advantages and disadvantages of the two traditional methods above, and proposes a hybrid method of on-line verification which synthesizes the advantages of the two traditional methods. This hybrid method can meet the requirements of accurate on-line verification.

  2. Data Exchanges and Verifications Online (DEVO)

    Data.gov (United States)

    Social Security Administration — DEVO is the back-end application for processing SSN verifications and data exchanges. DEVO uses modern technology for parameter driven processing of both batch and...

  3. Analyzing personalized policies for online biometric verification.

    Directory of Open Access Journals (Sweden)

    Apaar Sadhwani

    Full Text Available Motivated by India's nationwide biometric program for social inclusion, we analyze verification (i.e., one-to-one matching in the case where we possess similarity scores for 10 fingerprints and two irises between a resident's biometric images at enrollment and his biometric images during his first verification. At subsequent verifications, we allow individualized strategies based on these 12 scores: we acquire a subset of the 12 images, get new scores for this subset that quantify the similarity to the corresponding enrollment images, and use the likelihood ratio (i.e., the likelihood of observing these scores if the resident is genuine divided by the corresponding likelihood if the resident is an imposter to decide whether a resident is genuine or an imposter. We also consider two-stage policies, where additional images are acquired in a second stage if the first-stage results are inconclusive. Using performance data from India's program, we develop a new probabilistic model for the joint distribution of the 12 similarity scores and find near-optimal individualized strategies that minimize the false reject rate (FRR subject to constraints on the false accept rate (FAR and mean verification delay for each resident. Our individualized policies achieve the same FRR as a policy that acquires (and optimally fuses 12 biometrics for each resident, which represents a five (four, respectively log reduction in FRR relative to fingerprint (iris, respectively policies previously proposed for India's biometric program. The mean delay is [Formula: see text] sec for our proposed policy, compared to 30 sec for a policy that acquires one fingerprint and 107 sec for a policy that acquires all 12 biometrics. This policy acquires iris scans from 32-41% of residents (depending on the FAR and acquires an average of 1.3 fingerprints per resident.

  4. Analyzing personalized policies for online biometric verification.

    Science.gov (United States)

    Sadhwani, Apaar; Yang, Yan; Wein, Lawrence M

    2014-01-01

    Motivated by India's nationwide biometric program for social inclusion, we analyze verification (i.e., one-to-one matching) in the case where we possess similarity scores for 10 fingerprints and two irises between a resident's biometric images at enrollment and his biometric images during his first verification. At subsequent verifications, we allow individualized strategies based on these 12 scores: we acquire a subset of the 12 images, get new scores for this subset that quantify the similarity to the corresponding enrollment images, and use the likelihood ratio (i.e., the likelihood of observing these scores if the resident is genuine divided by the corresponding likelihood if the resident is an imposter) to decide whether a resident is genuine or an imposter. We also consider two-stage policies, where additional images are acquired in a second stage if the first-stage results are inconclusive. Using performance data from India's program, we develop a new probabilistic model for the joint distribution of the 12 similarity scores and find near-optimal individualized strategies that minimize the false reject rate (FRR) subject to constraints on the false accept rate (FAR) and mean verification delay for each resident. Our individualized policies achieve the same FRR as a policy that acquires (and optimally fuses) 12 biometrics for each resident, which represents a five (four, respectively) log reduction in FRR relative to fingerprint (iris, respectively) policies previously proposed for India's biometric program. The mean delay is [Formula: see text] sec for our proposed policy, compared to 30 sec for a policy that acquires one fingerprint and 107 sec for a policy that acquires all 12 biometrics. This policy acquires iris scans from 32-41% of residents (depending on the FAR) and acquires an average of 1.3 fingerprints per resident.

  5. Online Signature Verification Based on DCT and Sparse Representation.

    Science.gov (United States)

    Liu, Yishu; Yang, Zhihua; Yang, Lihua

    2015-11-01

    In this paper, a novel online signature verification technique based on discrete cosine transform (DCT) and sparse representation is proposed. We find a new property of DCT, which can be used to obtain a compact representation of an online signature using a fixed number of coefficients, leading to simple matching procedures and providing an effective alternative to deal with time series of different lengths. The property is also used to extract energy features. Furthermore, a new attempt to apply sparse representation to online signature verification is made, and a novel task-specific method for building overcomplete dictionaries is proposed, then sparsity features are extracted. Finally, energy features and sparsity features are concatenated to form a feature vector. Experiments are conducted on the Sabancı University's Signature Database (SUSIG)-Visual and SVC2004 databases, and the results show that our proposed method authenticates persons very reliably with a verification performance which is better than those of state-of-the-art methods on the same databases.

  6. Frame average optimization of cine-mode EPID images used for routine clinical in vivo patient dose verification of VMAT deliveries

    Energy Technology Data Exchange (ETDEWEB)

    McCowan, P. M., E-mail: pmccowan@cancercare.mb.ca [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada and Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); McCurdy, B. M. C. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Radiology, University of Manitoba, 820 Sherbrook Street, Winnipeg, Manitoba R3A 1R9 (Canada)

    2016-01-15

    Purpose: The in vivo 3D dose delivered to a patient during volumetric modulated arc therapy (VMAT) delivery can be calculated using electronic portal imaging device (EPID) images. These images must be acquired in cine-mode (i.e., “movie” mode) in order to capture the time-dependent delivery information. The angle subtended by each cine-mode EPID image during an arc can be changed via the frame averaging number selected within the image acquisition software. A large frame average number will decrease the EPID’s angular resolution and will result in a decrease in the accuracy of the dose information contained within each image. Alternatively, less EPID images acquired per delivery will decrease the overall 3D patient dose calculation time, which is appealing for large-scale clinical implementation. Therefore, the purpose of this study was to determine the optimal frame average value per EPID image, defined as the highest frame averaging that can be used without an appreciable loss in 3D dose reconstruction accuracy for VMAT treatments. Methods: Six different VMAT plans and six different SBRT-VMAT plans were delivered to an anthropomorphic phantom. Delivery was carried out on a Varian 2300ix model linear accelerator (Linac) equipped with an aS1000 EPID running at a frame acquisition rate of 7.5 Hz. An additional PC was set up at the Linac console area, equipped with specialized frame-grabber hardware and software packages allowing continuous acquisition of all EPID frames during delivery. Frames were averaged into “frame-averaged” EPID images using MATLAB. Each frame-averaged data set was used to calculate the in vivo dose to the patient and then compared to the single EPID frame in vivo dose calculation (the single frame calculation represents the highest possible angular resolution per EPID image). A mean percentage dose difference of low dose (<20% prescription dose) and high dose regions (>80% prescription dose) was calculated for each frame averaged

  7. In aqua vivo EPID dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Wendling, Markus; McDermott, Leah N.; Mans, Anton; Olaciregui-Ruiz, Igor; Pecharroman-Gallego, Raul; Sonke, Jan-Jakob; Stroom, Joep; Herk, Marcel J.; Mijnheer, Ben van [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands)

    2012-01-15

    Purpose: At the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital in vivo dosimetry using an electronic portal imaging device (EPID) has been implemented for almost all high-energy photon treatments of cancer with curative intent. Lung cancer treatments were initially excluded, because the original back-projection dose-reconstruction algorithm uses water-based scatter-correction kernels and therefore does not account for tissue inhomogeneities accurately. The aim of this study was to test a new method, in aqua vivo EPID dosimetry, for fast dose verification of lung cancer irradiations during actual patient treatment. Methods: The key feature of our method is the dose reconstruction in the patient from EPID images, obtained during the actual treatment, whereby the images have been converted to a situation as if the patient consisted entirely of water; hence, the method is termed in aqua vivo. This is done by multiplying the measured in vivo EPID image with the ratio of two digitally reconstructed transmission images for the unit-density and inhomogeneous tissue situation. For dose verification, a comparison is made with the calculated dose distribution with the inhomogeneity correction switched off. IMRT treatment verification is performed for each beam in 2D using a 2D {gamma} evaluation, while for the verification of volumetric-modulated arc therapy (VMAT) treatments in 3D a 3D {gamma} evaluation is applied using the same parameters (3%, 3 mm). The method was tested using two inhomogeneous phantoms simulating a tumor in lung and measuring its sensitivity for patient positioning errors. Subsequently five IMRT and five VMAT clinical lung cancer treatments were investigated, using both the conventional back-projection algorithm and the in aqua vivo method. The verification results of the in aqua vivo method were statistically analyzed for 751 lung cancer patients treated with IMRT and 50 lung cancer patients treated with VMAT. Results: The improvements by

  8. Online adaptation and verification of VMAT

    Energy Technology Data Exchange (ETDEWEB)

    Crijns, Wouter, E-mail: wouter.crijns@uzleuven.be [KU Leuven Department of Oncology, Laboratory of Experimental Radiotherapy, Herestraat 49, Leuven 3000, Belgium and KU Leuven Medical Imaging Research Center, Herestraat 49, Leuven 3000 (Belgium); Defraene, Gilles; Depuydt, Tom; Haustermans, Karin [KU Leuven Department of Oncology, Laboratory of Experimental Radiotherapy, Herestraat 49, Leuven 3000 (Belgium); Van Herck, Hans [KU Leuven Medical Imaging Research Center, Herestraat 49, Leuven 3000, Belgium and KU Leuven Department of Electrical Engineering (ESAT), PSI, Center for Processing Speech and Images, Leuven 3000 (Belgium); Maes, Frederik [KU Leuven Department of Electrical Engineering (ESAT), PSI, Center for Processing Speech and Images, Leuven 3000, Belgium and KU Leuven iMinds - Medical IT Department, Leuven 3000 (Belgium); Van den Heuvel, Frank [Department of Oncology, MRC-CR-UK Gray Institute of Radiation Oncology and Biology, University of Oxford, Oxford OX1 2JD (United Kingdom)

    2015-07-15

    Purpose: This work presents a method for fast volumetric modulated arc therapy (VMAT) adaptation in response to interfraction anatomical variations. Additionally, plan parameters extracted from the adapted plans are used to verify the quality of these plans. The methods were tested as a prostate class solution and compared to replanning and to their current clinical practice. Methods: The proposed VMAT adaptation is an extension of their previous intensity modulated radiotherapy (IMRT) adaptation. It follows a direct (forward) planning approach: the multileaf collimator (MLC) apertures are corrected in the beam’s eye view (BEV) and the monitor units (MUs) are corrected using point dose calculations. All MLC and MU corrections are driven by the positions of four fiducial points only, without need for a full contour set. Quality assurance (QA) of the adapted plans is performed using plan parameters that can be calculated online and that have a relation to the delivered dose or the plan quality. Five potential parameters are studied for this purpose: the number of MU, the equivalent field size (EqFS), the modulation complexity score (MCS), and the components of the MCS: the aperture area variability (AAV) and the leaf sequence variability (LSV). The full adaptation and its separate steps were evaluated in simulation experiments involving a prostate phantom subjected to various interfraction transformations. The efficacy of the current VMAT adaptation was scored by target mean dose (CTV{sub mean}), conformity (CI{sub 95%}), tumor control probability (TCP), and normal tissue complication probability (NTCP). The impact of the adaptation on the plan parameters (QA) was assessed by comparison with prediction intervals (PI) derived from a statistical model of the typical variation of these parameters in a population of VMAT prostate plans (n = 63). These prediction intervals are the adaptation equivalent of the tolerance tables for couch shifts in the current clinical

  9. INTrEPID

    DEFF Research Database (Denmark)

    Pedersen, Thomas; Ravn, Anders Peter; Skou, Arne

    2014-01-01

    We present the objectives, activities and some preliminary results of the FP7 STREP project INTrEPID (INTelligent systems for Energy Prosumer buildIngs at District level).......We present the objectives, activities and some preliminary results of the FP7 STREP project INTrEPID (INTelligent systems for Energy Prosumer buildIngs at District level)....

  10. WE-G-BRB-02: MU-EPID an EPID Based Tool for IMRT Quality Assurance.

    Science.gov (United States)

    Quino, L Vazquez; Stathakis, S; Gutierrez, A; Esquivel, C; Alkhatib, H; Papanikolaou, N

    2012-06-01

    A software program (MU-EPID) has been developed to perform patient specific IMRT pre-treatment QA verification using an electronic portal imaging device. The software converts measured images of intensity modulated beams delivered to an EPID, into fluence maps that can be imported in the treatment planning system. The dose can then be calculated in the patient anatomy and compared against the patient's treatment plan for QA purposes. We first benchmarked the software using as a patient a cylindrical phantom. An aSi-1000 EPID mounted on a Varian Novalis linear accelerator was used for the image acquisition. Finally, IMRT plans from different treatment sites were used to further validate this in- house software. QA analysis was performed by evaluation of isodose distributions, DVH comparison and 2D gamma analysis. The validation study with the cylindrical phantom showed that the dose to the ion chamber measurement point was in good agreement with both the original treatment plan and the MU-EPID reconstructed dose. Similar results were found for the clinical cases that we studied. A gamma analysis of the dose to the isocenter plane was performed for each plan. Using 3% and 3 mm as the evaluation criteria, resulted in an average of 97.44% of pixels passing the analysis (gamma<1). Good agreement was also observed for the DVH, isodose and profile comparisons between the clinically delivered IMRT plan and the MU-EPID derived dose calculation. The results of the present investigation suggest that MU-EPID can be used in a clinical environment and can be used for patient specific QA for IMRT plans. This work has been supported by the SCOA. © 2012 American Association of Physicists in Medicine.

  11. Accurate IMRT fluence verification for prostate cancer patients using 'in-vivo' measured EPID images and in-room acquired kilovoltage cone-beam CT scans

    NARCIS (Netherlands)

    A.S.A.M. Ali (Ali Sid Ahmed M.); M.L.P. Dirkx (Maarten); R.M. Cools (Ruud); B.J.M. Heijmen (Ben)

    2013-01-01

    textabstractBackground: To investigate for prostate cancer patients the comparison of 'in-vivo' measured portal dose images (PDIs) with predictions based on a kilovoltage cone-beam CT scan (CBCT), acquired during the same treatment fraction, as an alternative for pre-treatment verification. For eval

  12. Comparative analysis for dose verification of volumetric modulated arc therapy by Varian EPID and PTW Detector 729%Varian EPID和PTW Detector 729在容积旋转调强剂量验证中的比较分析

    Institute of Scientific and Technical Information of China (English)

    孟慧鹏; 孙小喆; 王昊; 孙劲松; 郑爱青; 梁克明

    2015-01-01

    The data of dose verification between Varian EPID and PTW Detector 729 is compared to discuss whether the statistics difference of gamma passing rates between the two methods exists. The RapidArc plans for different body sites of 30 patients undergoing radiation treatment with RapidArc technique were used for the generation of the two verification plans, with one for using the electronic portal imaging device (EPID) of Varian RapidArc systems (Varian medical systems), and the other for using the chamber array detector from PTW(PTW Detector 729). Seven comparative experiments were performed for each pair of the plans, which were measurements inside the target, inside the effective detection area, and the target with expansions of 5 mm,10 mm, 20 mm, 30 mm, and 50 mm, respectively. The gamma passing rate of 3%/3 mm andF-test were used in the quantitative analysis. No statistical difference between the two methods was found for the measurement of the area of target with 30 mm expansion (F=0.395,p>0.05), while statistical difference existed (p0.05),其余6组结果均有统计学差异(p<0.05).两种剂量验证方式各有利弊,对其结论进行比较分析可更全面保障调强放疗计划验证的准确性.

  13. Impact of the frequency of online verifications on the patient set-up accuracy and set-up margins

    Directory of Open Access Journals (Sweden)

    Mohamed Adel

    2011-08-01

    Full Text Available Abstract Purpose The purpose of the study was to evaluate the patient set-up error of different anatomical sites, to estimate the effect of different frequencies of online verifications on the patient set-up accuracy, and to calculate margins to accommodate for the patient set-up error (ICRU set-up margin, SM. Methods and materials Alignment data of 148 patients treated with inversed planned intensity modulated radiotherapy (IMRT or three-dimensional conformal radiotherapy (3D-CRT of the head and neck (n = 31, chest (n = 72, abdomen (n = 15, and pelvis (n = 30 were evaluated. The patient set-up accuracy was assessed using orthogonal megavoltage electronic portal images of 2328 fractions of 173 planning target volumes (PTV. In 25 patients, two PTVs were analyzed where the PTVs were located in different anatomical sites and treated in two different radiotherapy courses. The patient set-up error and the corresponding SM were retrospectively determined assuming no online verification, online verification once a week and online verification every other day. Results The SM could be effectively reduced with increasing frequency of online verifications. However, a significant frequency of relevant set-up errors remained even after online verification every other day. For example, residual set-up errors larger than 5 mm were observed on average in 18% to 27% of all fractions of patients treated in the chest, abdomen and pelvis, and in 10% of fractions of patients treated in the head and neck after online verification every other day. Conclusion In patients where high set-up accuracy is desired, daily online verification is highly recommended.

  14. EPID dosimetry for pretreatment quality assurance with two commercial systems.

    Science.gov (United States)

    Bailey, Daniel W; Kumaraswamy, Lalith; Bakhtiari, Mohammad; Malhotra, Harish K; Podgorsak, Matthew B

    2012-07-05

    This study compares the EPID dosimetry algorithms of two commercial systems for pretreatment QA, and analyzes dosimetric measurements made with each system alongside the results obtained with a standard diode array. 126 IMRT fields are examined with both EPID dosimetry systems (EPIDose by Sun Nuclear Corporation, Melbourne FL, and Portal Dosimetry by Varian Medical Systems, Palo Alto CA) and the diode array, MapCHECK (also by Sun Nuclear Corporation). Twenty-six VMAT arcs of varying modulation complexity are examined with the EPIDose and MapCHECK systems. Optimization and commissioning testing of the EPIDose physics model is detailed. Each EPID IMRT QA system is tested for sensitivity to critical TPS beam model errors. Absolute dose gamma evaluation (3%, 3 mm, 10% threshold, global normalization to the maximum measured dose) yields similar results (within 1%-2%) for all three dosimetry modalities, except in the case of off-axis breast tangents. For these off-axis fields, the Portal Dosimetry system does not adequately model EPID response, though a previously-published correction algorithm improves performance. Both MapCHECK and EPIDose are found to yield good results for VMAT QA, though limitations are discussed. Both the Portal Dosimetry and EPIDose algorithms, though distinctly different, yield similar results for the majority of clinical IMRT cases, in close agreement with a standard diode array. Portal dose image prediction may overlook errors in beam modeling beyond the calculation of the actual fluence, while MapCHECK and EPIDose include verification of the dose calculation algorithm, albeit in simplified phantom conditions (and with limited data density in the case of the MapCHECK detector). Unlike the commercial Portal Dosimetry package, the EPIDose algorithm (when sufficiently optimized) allows accurate analysis of EPID response for off-axis, asymmetric fields, and for orthogonal VMAT QA. Other forms of QA are necessary to supplement the limitations of the

  15. SU-E-T-602: Patient-Specific Online Dose Verification Based On Transmission Detector Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Thoelking, J; Yuvaraj, S; Jens, F; Lohr, F; Wenz, F; Wertz, H; Wertz, H [University Medical Center Mannheim, University of Heidelberg, Mannheim, Baden-Wuerttemberg (Germany)

    2015-06-15

    Purpose: Intensity modulated radiotherapy requires a comprehensive quality assurance program in general and ideally independent verification of dose delivery. Since conventional 2D detector arrays allow only pre-treatment verification, there is a debate concerning the need of online dose verification. This study presents the clinical performance, including dosimetric plan verification in 2D as well as in 3D and the error detection abilities of a new transmission detector (TD) for online dose verification of 6MV photon beam. Methods: To validate the dosimetric performance of the new device, dose reconstruction based on TD measurements were compared to a conventional pre-treatment verification method (reference) and treatment planning system (TPS) for 18 IMRT and VMAT treatment plans. Furthermore, dose reconstruction inside the patient based on TD read-out was evaluated by comparing various dose volume indices and 3D gamma evaluations against independent dose computation and TPS. To investigate the sensitivity of the new device, different types of systematic and random errors for leaf positions and linac output were introduced in IMRT treatment sequences. Results: The 2D gamma index evaluation of transmission detector based dose reconstruction showed an excellent agreement for all IMRT and VMAT plans compared to reference measurements (99.3±1.2)% and TPS (99.1±0.7)%. Good agreement was also obtained for 3D dose reconstruction based on TD read-out compared to dose computation (mean gamma value of PTV = 0.27±0.04). Only a minimal dose underestimation within the target volume was observed when analyzing DVH indices (<1%). Positional errors in leaf banks larger than 1mm and errors in linac output larger than 2% could clearly identified with the TD. Conclusion: Since 2D and 3D evaluations for all IMRT and VMAT treatment plans were in excellent agreement with reference measurements and dose computation, the new TD is suitable to qualify for routine treatment plan

  16. Dosimetry in radiotherapy using a-Si EPIDs: Systems, methods, and applications focusing on 3D patient dose estimation

    Science.gov (United States)

    McCurdy, B. M. C.

    2013-06-01

    An overview is provided of the use of amorphous silicon electronic portal imaging devices (EPIDs) for dosimetric purposes in radiation therapy, focusing on 3D patient dose estimation. EPIDs were originally developed to provide on-treatment radiological imaging to assist with patient setup, but there has also been a natural interest in using them as dosimeters since they use the megavoltage therapy beam to form images. The current generation of clinically available EPID technology, amorphous-silicon (a-Si) flat panel imagers, possess many characteristics that make them much better suited to dosimetric applications than earlier EPID technologies. Features such as linearity with dose/dose rate, high spatial resolution, realtime capability, minimal optical glare, and digital operation combine with the convenience of a compact, retractable detector system directly mounted on the linear accelerator to provide a system that is well-suited to dosimetric applications. This review will discuss clinically available a-Si EPID systems, highlighting dosimetric characteristics and remaining limitations. Methods for using EPIDs in dosimetry applications will be discussed. Dosimetric applications using a-Si EPIDs to estimate three-dimensional dose in the patient during treatment will be overviewed. Clinics throughout the world are implementing increasingly complex treatments such as dynamic intensity modulated radiation therapy and volumetric modulated arc therapy, as well as specialized treatment techniques using large doses per fraction and short treatment courses (ie. hypofractionation and stereotactic radiosurgery). These factors drive the continued strong interest in using EPIDs as dosimeters for patient treatment verification.

  17. Time dependent pre-treatment EPID dosimetry for standard and FFF VMAT.

    Science.gov (United States)

    Podesta, Mark; Nijsten, Sebastiaan M J J G; Persoon, Lucas C G G; Scheib, Stefan G; Baltes, Christof; Verhaegen, Frank

    2014-08-21

    Methods to calibrate Megavoltage electronic portal imaging devices (EPIDs) for dosimetry have been previously documented for dynamic treatments such as intensity modulated radiotherapy (IMRT) using flattened beams and typically using integrated fields. While these methods verify the accumulated field shape and dose, the dose rate and differential fields remain unverified. The aim of this work is to provide an accurate calibration model for time dependent pre-treatment dose verification using amorphous silicon (a-Si) EPIDs in volumetric modulated arc therapy (VMAT) for both flattened and flattening filter free (FFF) beams. A general calibration model was created using a Varian TrueBeam accelerator, equipped with an aS1000 EPID, for each photon spectrum 6 MV, 10 MV, 6 MV-FFF, 10 MV-FFF. As planned VMAT treatments use control points (CPs) for optimization, measured images are separated into corresponding time intervals for direct comparison with predictions. The accuracy of the calibration model was determined for a range of treatment conditions. Measured and predicted CP dose images were compared using a time dependent gamma evaluation using criteria (3%, 3 mm, 0.5 sec). Time dependent pre-treatment dose verification is possible without an additional measurement device or phantom, using the on-board EPID. Sufficient data is present in trajectory log files and EPID frame headers to reliably synchronize and resample portal images. For the VMAT plans tested, significantly more deviation is observed when analysed in a time dependent manner for FFF and non-FFF plans than when analysed using only the integrated field. We show EPID-based pre-treatment dose verification can be performed on a CP basis for VMAT plans. This model can measure pre-treatment doses for both flattened and unflattened beams in a time dependent manner which highlights deviations that are missed in integrated field verifications.

  18. Time dependent pre-treatment EPID dosimetry for standard and FFF VMAT

    Science.gov (United States)

    Podesta, Mark; Nijsten, Sebastiaan M. J. J. G.; Persoon, Lucas C. G. G.; Scheib, Stefan G.; Baltes, Christof; Verhaegen, Frank

    2014-08-01

    Methods to calibrate Megavoltage electronic portal imaging devices (EPIDs) for dosimetry have been previously documented for dynamic treatments such as intensity modulated radiotherapy (IMRT) using flattened beams and typically using integrated fields. While these methods verify the accumulated field shape and dose, the dose rate and differential fields remain unverified. The aim of this work is to provide an accurate calibration model for time dependent pre-treatment dose verification using amorphous silicon (a-Si) EPIDs in volumetric modulated arc therapy (VMAT) for both flattened and flattening filter free (FFF) beams. A general calibration model was created using a Varian TrueBeam accelerator, equipped with an aS1000 EPID, for each photon spectrum 6 MV, 10 MV, 6 MV-FFF, 10 MV-FFF. As planned VMAT treatments use control points (CPs) for optimization, measured images are separated into corresponding time intervals for direct comparison with predictions. The accuracy of the calibration model was determined for a range of treatment conditions. Measured and predicted CP dose images were compared using a time dependent gamma evaluation using criteria (3%, 3 mm, 0.5 sec). Time dependent pre-treatment dose verification is possible without an additional measurement device or phantom, using the on-board EPID. Sufficient data is present in trajectory log files and EPID frame headers to reliably synchronize and resample portal images. For the VMAT plans tested, significantly more deviation is observed when analysed in a time dependent manner for FFF and non-FFF plans than when analysed using only the integrated field. We show EPID-based pre-treatment dose verification can be performed on a CP basis for VMAT plans. This model can measure pre-treatment doses for both flattened and unflattened beams in a time dependent manner which highlights deviations that are missed in integrated field verifications.

  19. In aqua vivo EPID dosimetry

    NARCIS (Netherlands)

    Wendling, M.; McDermott, L.N.; Mans, A.; Olaciregui-Ruiz, I.; Pecharroman-Gallego, R.; Sonke, J.J.; Stroom, J.; Herk, M. van; Mijnheer, B.J.

    2012-01-01

    PURPOSE: At the Netherlands Cancer Institute--Antoni van Leeuwenhoek Hospital in vivo dosimetry using an electronic portal imaging device (EPID) has been implemented for almost all high-energy photon treatments of cancer with curative intent. Lung cancer treatments were initially excluded, because t

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

    Energy Technology Data Exchange (ETDEWEB)

    Aldawood, Saad [Ludwig-Maximilians-Universitaet Muenchen (Germany); King Saud University, Riyadh (Saudi Arabia); Lang, Christian; Lutter, Rudolf; Bortfeldt, Jonathan; Parodi, Katia; Thirolf, Peter G. [Ludwig-Maximilians-Universitaet Muenchen (Germany); Kolff, Hugh van der [Ludwig-Maximilians-Universitaet Muenchen (Germany); Delft University of Technology (Netherlands); Maier, Ludwig [Technische Universitaet Muenchen (Germany)

    2014-07-01

    Precise and preferably online ion beam range verification is a mandatory prerequisite to fully exploit the advantages of hadron-therapy in cancer treatment. Our aim is to develop an imaging system based on a Compton camera designed to detect prompt γ rays induced by nuclear reactions between ion beam and biological tissue. The Compton camera prototype consists of a stack of double-sided Si-strip detectors (DSSSD) acting as scatterers, while the absorber is formed by a LaBr{sub 3} scintillator crystal read out by a position-sensitive multi-anode photomultiplier. The LaBr{sub 3} detector was characterized with both absorptive and reflective side-face wrapping materials. Comparative studies of energy and time resolution, photopeak detection efficiency and spatial resolution are presented together with first tests of the complete camera system.

  2. Online Verification of Control Parameter Calculations in Communication Based Train Control System

    CERN Document Server

    Bu, Lei; Wang, Linzhang; Li, Xuandong

    2011-01-01

    Communication Based Train Control (CBTC) system is the state-of-the-art train control system. In a CBTC system, to guarantee the safety of train operation, trains communicate with each other intensively and adjust their control modes autonomously by computing critical control parameters, e.g. velocity range, according to the information they get. As the correctness of the control parameters generated are critical to the safety of the system, a method to verify these parameters is a strong desire in the area of train control system. In this paper, we present our ideas of how to model and verify the control parameter calculations in a CBTC system efficiently. - As the behavior of the system is highly nondeterministic, it is difficult to build and verify the complete behavior space model of the system online in advance. Thus, we propose to model the system according to the ongoing behavior model induced by the control parameters. - As the parameters are generated online and updated very quickly, the verification...

  3. A back-projection algorithm in the presence of an extra attenuating medium: towards EPID dosimetry for the MR-Linac

    Science.gov (United States)

    Torres-Xirau, I.; Olaciregui-Ruiz, I.; Rozendaal, R. A.; González, P.; Mijnheer, B. J.; Sonke, J.-J.; van der Heide, U. A.; Mans, A.

    2017-08-01

    In external beam radiotherapy, electronic portal imaging devices (EPIDs) are frequently used for pre-treatment and for in vivo dose verification. Currently, various MR-guided radiotherapy systems are being developed and clinically implemented. Independent dosimetric verification is highly desirable. For this purpose we adapted our EPID-based dose verification system for use with the MR-Linac combination developed by Elekta in cooperation with UMC Utrecht and Philips. In this study we extended our back-projection method to cope with the presence of an extra attenuating medium between the patient and the EPID. Experiments were performed at a conventional linac, using an aluminum mock-up of the MRI scanner housing between the phantom and the EPID. For a 10 cm square field, the attenuation by the mock-up was 72%, while 16% of the remaining EPID signal resulted from scattered radiation. 58 IMRT fields were delivered to a 20 cm slab phantom with and without the mock-up. EPID reconstructed dose distributions were compared to planned dose distributions using the γ -evaluation method (global, 3%, 3 mm). In our adapted back-projection algorithm the averaged {γmean} was 0.27+/- 0.06 , while in the conventional it was 0.28+/- 0.06 . Dose profiles of several square fields reconstructed with our adapted algorithm showed excellent agreement when compared to TPS.

  4. Clinical evaluation of 3D/3D MRI-CBCT automatching on brain tumors for online patient setup verification - A step towards MRI-based treatment planning

    DEFF Research Database (Denmark)

    Buhl, Sune K.; Duun-Christensen, Anne Katrine; Kristensen, Brian H.

    2010-01-01

    Background. Magnetic Resonance Imaging (MRI) is often used in modern day radiotherapy (RT) due to superior soft tissue contrast. However, treatment planning based solely on MRI is restricted due to e. g. the limitations of conducting online patient setup verification using MRI as reference....... In this study 3D/3D MRI-Cone Beam CT (CBCT) automatching for online patient setup verification was investigated. Material and methods. Initially, a multi-modality phantom was constructed and used for a quantitative comparison of CT-CBCT and MRI-CBCT automatching. Following the phantom experiment three patients...

  5. Online pretreatment verification of high-dose rate brachytherapy using an imaging panel

    Science.gov (United States)

    Fonseca, Gabriel P.; Podesta, Mark; Bellezzo, Murillo; Van den Bosch, Michiel R.; Lutgens, Ludy; Vanneste, Ben G. L.; Voncken, Robert; Van Limbergen, Evert J.; Reniers, Brigitte; Verhaegen, Frank

    2017-07-01

    Brachytherapy is employed to treat a wide variety of cancers. However, an accurate treatment verification method is currently not available. This study describes a pre-treatment verification system that uses an imaging panel (IP) to verify important aspects of the treatment plan. A detailed modelling of the IP was only possible with an extensive calibration performed using a robotic arm. Irradiations were performed with a high dose rate (HDR) 192Ir source within a water phantom. An empirical fit was applied to measure the distance between the source and the detector so 3D Cartesian coordinates of the dwell positions can be obtained using a single panel. The IP acquires 7.14 fps to verify the dwell times, dwell positions and air kerma strength (Sk). A gynecological applicator was used to create a treatment plan that was registered with a CT image of the water phantom used during the experiments for verification purposes. Errors (shifts, exchanged connections and wrong dwell times) were simulated to verify the proposed verification system. Cartesian source positions (panel measurement plane) have a standard deviation of about 0.02 cm. The measured distance between the source and the panel (z-coordinate) have a standard deviation up to 0.16 cm and maximum absolute error of  ≈0.6 cm if the signal is close to sensitive limit of the panel. The average response of the panel is very linear with Sk. Therefore, Sk measurements can be performed with relatively small errors. The measured dwell times show a maximum error of 0.2 s which is consistent with the acquisition rate of the panel. All simulated errors were clearly identified by the proposed system. The use of IPs is not common in brachytherapy, however, it provides considerable advantages. It was demonstrated that the IP can accurately measure Sk, dwell times and dwell positions.

  6. Evaluation of usefulness of portal image using Electronic Portal Imaging Device (EPID) in the patients who received pelvic radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Woo Chul; Kim, Heon Jong; Park, Seong Young; Cho, Young Kap; Loh, John J. K. [College of Medicine, Inha Univ., Pusan (Korea, Republic of); Park, Won; Suh, Chang Ok; Kim, Gwi Eon [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)

    1998-12-01

    To evaluate the usefulness of electronic portal imaging device through objective compare of the images acquired using an EPID and a conventional port film. From Apr. to Oct. 1997, a total of 150 sets of images from 20 patients who received radiation therapy in the pelvis area were evaluated in the Inha University Hospital and Severance Hospital. A dual image recording technique was devised to obtain both electronic portal images and port film images simultaneously with one treatment course. We did not perform double exposure. Five to ten images were acquired from each patient. All images were acquired from posteroanterior (PA) view except images from two patients. A dose rate of 100-300 MU/min and a 10-MV X-ray beam were used and 2-10 MUs were required to produce a verification image during treatment. Kodak diagnostic film with metal/film imaging cassette which was located on the top of the EPID detector was used for the port film. The source to detector distance was 140 cm. Eight anatomical landmarks (pelvic brim, sacrum, acetabulum, iliopectineal line, symphysis, ischium, obturator foramen, sacroiliac joint) were assessed. Four radiation oncologist joined to evaluate each image. The individual landmarks in the port film or in the EPID were rated-very clear (1), clear (2), visible (3), notclear (4), not visible (5). Using an video camera based EPID system, there was no difference of image quality between no enhanced EPID images and port film images. However, when we provided some change with window level for the portal image, the visibility of the sacrum and obturator foramen was improved in the portal images than in the port film images. All anatomical landmarks were more visible in the portal images than in the port film when we applied the CLAHE mode enhancement. The images acquired using an matrix ion chamber type EPID were also improved image quality after window level adjustment. The quality of image acquired using an electronic portal imaging device was

  7. Identity Verification Mechanism for Detecting Fake Profiles in Online Social Networks

    OpenAIRE

    Ali M. Meligy; Hani M. Ibrahim; Mohamed F. Torky

    2017-01-01

    Impersonating users' identity in Online Social Networks (OSNs) is one of the open dilemmas from security and privacy point of view. Scammers and adversaries seek to create set of fake profiles to carry out malicious behaviors and online social crimes in social media. Recognizing the identity of Fake Profiles is an urgent issue of concern to the attention of researchers. In this paper, we propose a detection technique called Fake Profile Recognizer (FPR) for verifying the identity of profiles,...

  8. Grazing-Angle Fourier Transform Infrared Spectroscopy for Online Surface Cleanliness Verification. Year 1

    Science.gov (United States)

    2000-07-01

    As part of the Online Surface Cleanliness Project, the Naval Facilities Engineering Service Center (NFESC) conducted a study of grazing-angle...demonstrated in the laboratory for the detection of organic contaminant residues on reflective surfaces. Applications where surface cleanliness is critical

  9. Identity Verification Mechanism for Detecting Fake Profiles in Online Social Networks

    Directory of Open Access Journals (Sweden)

    Ali M. Meligy

    2017-01-01

    Full Text Available Impersonating users' identity in Online Social Networks (OSNs is one of the open dilemmas from security and privacy point of view. Scammers and adversaries seek to create set of fake profiles to carry out malicious behaviors and online social crimes in social media. Recognizing the identity of Fake Profiles is an urgent issue of concern to the attention of researchers. In this paper, we propose a detection technique called Fake Profile Recognizer (FPR for verifying the identity of profiles, and detecting the fake profiles in OSNs. The detection method in our proposed technique is based on utilizing Regular Expression (RE and Deterministic Finite Automaton (DFA approaches. We evaluated our proposed detection technique on three datasets types of OSNs: Facebook, Google+, and Twitter. The results explored high Precision, Recall, accuracy, and low False Positive Rates (FPR of detecting Fake Profiles in the three datasets.

  10. Dosimetric properties of an amorphous-silicon EPID used in continuous acquisition mode for application to dynamic and arc IMRT.

    Science.gov (United States)

    McCurdy, B M C; Greer, P B

    2009-07-01

    Dosimetric properties of an amorphous-silicon electronic portal imaging device (EPID) operated in a real-time acquisition mode were investigated. This mode will be essential for time-resolved dose verification of dynamic (sliding window) intensity modulated radiation therapy (IMRT) and intensity modulated arc radiation therapy (arc-IMRT). The EPID was used in continuous acquisition mode (i.e., "cine" mode) where individual sequential image frames are acquired in real time. The properties studied include dose linearity, reproducibility of response, and image stability. Results of using the continuous acquisition mode with several example treatments including dynamic IMRT, arc treatment, and single-arc-IMRT are compared to results using the well-studied integrated acquisition mode (i.e., "frame averaging" or "IMRT" mode). Real-time EPID response was also compared to real-time ion-chamber data for selected points in the deliveries. The example treatment deliveries in both continuous and integrated acquisition modes were converted to arbitrary EPID dose units via a calibration field. The summation of all acquired continuous mode images was compared using percentage dose difference to the single image acquired in the integrated mode using in-field pixels only (defined as those pixels > 10% of maximum, in-field signal). Using the continuous acquisition mode, the EPID response was not linear with dose. It was found that the continuous mode dose response corresponded approximately to dropping one image per acquisition session. Reproducibility of EPID response to low monitor units (MUs) was found to be poor but greatly improved with increasing MU. Open field profiles were found to be stable in the cross-plane direction but required several frames to become stable in the in-plane direction. However, both of these issues are clinically insignificant due to arc-IMRT deliveries requiring relatively large monitor units (> 100 MU). Analysis of the five IMRT, arc, and arc

  11. Online Filtration of Stimuli for Microprocessor Verification%处理器验证激励在线筛选技术

    Institute of Scientific and Technical Information of China (English)

    郭崎

    2012-01-01

    如何生成高质量的验证激励是功能验证中的核心问题之一.随着功能验证的不断进行,验证激励的有效性也随之降低,为了提高验证激励的质量,提出一种在线筛选技术来处理验证激励.该技术采用单分类支持向量机来在线地构建分类器,以对新生成的验证激励是否冗余进行预测,如果是冗余的,则不进人仿真阶段进行仿真.在此基础上,进一步提出指令序列核函数来衡量不同指令序列的相似程度.实验结果表明,与约束随机生成技术相比,文中技术可以减少约83%的验证激励及79%的验证时间.%One of the most critical issues during functional verification is to generate highly effective stimuli. As verification proceeds, the effectiveness of verification stimuli decreases. To improve the effectiveness of stimuli, an online filteration technique to process is proposed to generated stimuli. This technique employs one-class support vector machines to online construct a classifier to predict whether or not a newly generated stimulus is redundant, and the predicted redundant stimulus will not be sent for simulation. Besides, we also propose an instruction sequence kernel to measure the similarities among instruction sequences. Experimental results demonstrate that this technique can reduce about 83% stimuli and 79 % verification time in comparison with conventional constrained random generation.

  12. ON-LINE MONITORING OF I&C TRANSMITTERS AND SENSORS FOR CALIBRATION VERIFICATION AND RESPONSE TIME TESTING WAS SUCCESSFULLY IMPLEMENTED AT ATR

    Energy Technology Data Exchange (ETDEWEB)

    Erickson, Phillip A.; O' Hagan, Ryan; Shumaker, Brent; Hashemian, H. M.

    2017-03-01

    The Advanced Test Reactor (ATR) has always had a comprehensive procedure to verify the performance of its critical transmitters and sensors, including RTDs, and pressure, level, and flow transmitters. These transmitters and sensors have been periodically tested for response time and calibration verification to ensure accuracy. With implementation of online monitoring techniques at ATR, the calibration verification and response time testing of these transmitters and sensors are verified remotely, automatically, hands off, include more portions of the system, and can be performed at almost any time during process operations. The work was done under a DOE funded SBIR project carried out by AMS. As a result, ATR is now able to save the manpower that has been spent over the years on manual calibration verification and response time testing of its temperature and pressure sensors and refocus those resources towards more equipment reliability needs. More importantly, implementation of OLM will help enhance the overall availability, safety, and efficiency. Together with equipment reliability programs of ATR, the integration of OLM will also help with I&C aging management goals of the Department of Energy and long-time operation of ATR.

  13. Evaluation of a fast method of EPID-based dosimetry for intensity modulated radiation therapy

    OpenAIRE

    Nelms, Benjamin E.; Rasmussen, Karl H.; Tomé, Wolfgang A.

    2010-01-01

    Electronic portal imaging devices (EPIDs) could potentially be useful for Intensity Modulated Radiation Therapy (IMRT) QA. The data density, high resolution, large active area, and efficiency of the MV EPID make it an attractive option. However, EPIDs were designed to be effective imaging devices, but not dosimeters, and as a result they do not measure dose in tissue-equivalent materials.

  14. SU-C-304-05: Use of Local Noise Power Spectrum and Wavelets in Comprehensive EPID Quality Assurance

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S; Gopal, A; Yan, G; Bassett, P; Park, C; Samant, S [University of Florida Health Science Center, Gainesville, FL (United States)

    2015-06-15

    Purpose: As EPIDs are increasingly used for IMRT QA and real-time treatment verification, comprehensive quality assurance (QA) of EPIDs becomes critical. Current QA with phantoms such as the Las Vegas and PIPSpro™ can fail in the early detection of EPID artifacts. Beyond image quality assessment, we propose a quantitative methodology using local noise power spectrum (NPS) to characterize image noise and wavelet transform to identify bad pixels and inter-subpanel flat-fielding artifacts. Methods: A total of 93 image sets including bar-pattern images and open exposure images were collected from four iViewGT a-Si EPID systems over three years. Quantitative metrics such as modulation transform function (MTF), NPS and detective quantum efficiency (DQE) were computed for each image set. Local 2D NPS was calculated for each subpanel. A 1D NPS was obtained by radial averaging the 2D NPS and fitted to a power-law function. R-square and slope of the linear regression analysis were used for panel performance assessment. Haar wavelet transformation was employed to identify pixel defects and non-uniform gain correction across subpanels. Results: Overall image quality was assessed with DQE based on empirically derived area under curve (AUC) thresholds. Using linear regression analysis of 1D NPS, panels with acceptable flat fielding were indicated by r-square between 0.8 and 1, and slopes of −0.4 to −0.7. However, for panels requiring flat fielding recalibration, r-square values less than 0.8 and slopes from +0.2 to −0.4 were observed. The wavelet transform successfully identified pixel defects and inter-subpanel flat fielding artifacts. Standard QA with the Las Vegas and PIPSpro phantoms failed to detect these artifacts. Conclusion: The proposed QA methodology is promising for the early detection of imaging and dosimetric artifacts of EPIDs. Local NPS can accurately characterize the noise level within each subpanel, while the wavelet transforms can detect bad pixels and

  15. Quality control of CML using EPID: cubic approximation technique; Control de calidad de CML usando EPID: tecnica de aproximacion cubica

    Energy Technology Data Exchange (ETDEWEB)

    Pino Leon, C.; Puertolas Hernandez, J. R.; Lozano Flores, F. J.; Larretxea Etxarri, R.

    2011-07-01

    In the implementation of IMRT in radiotherapy centers increasingly require more precise control of the linear accelerator quality. Specifically, the accuracy required in the quality control CML (multileaf collimator) over 0.5 mm 50n. In this sense, usually establishing in many centers using the technique of {sup g}arden fence{sup .} This image gives a 2 cm adjacent fields using EPID (Electronic Portal Image Device). In this paper we have developed a technique for automatic image analysis of EPID using ImageJ 1.43 thus increasing the accuracy and efficiency and removing the subjectivity of the analysis. (Author)

  16. SU-E-J-61: Monitoring Tumor Motion in Real-Time with EPID Imaging During Cervical Cancer Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Mao, W; Hrycushko, B; Yan, Y; Foster, R; Albuquerque, K [UT Southwestern Medical Center, Dallas, TX (United States)

    2015-06-15

    Purpose: Traditional external beam radiotherapy for cervical cancer requires setup by external skin marks. In order to improve treatment accuracy and reduce planning margin for more conformal therapy, it is essential to monitor tumor positions interfractionally and intrafractionally. We demonstrate feasibility of monitoring cervical tumor motion online using EPID imaging from Beam’s Eye View. Methods: Prior to treatment, 1∼2 cylindrical radio opaque markers were implanted into inferior aspect of cervix tumor. During external beam treatments on a Varian 2100C by 4-field 3D plans, treatment beam images were acquired continuously by an EPID. A Matlab program was developed to locate internal markers on MV images. Based on 2D marker positions obtained from different treatment fields, their 3D positions were estimated for every treatment fraction. Results: There were 398 images acquired during different treatment fractions of three cervical cancer patients. Markers were successfully located on every frame of image at an analysis speed of about 1 second per frame. Intrafraction motions were evaluated by comparing marker positions relative to the position on the first frame of image. The maximum intrafraction motion of the markers was 1.6 mm. Interfraction motions were evaluated by comparing 3D marker positions at different treatment fractions. The maximum interfraction motion was up to 10 mm. Careful comparison found that this is due to patient positioning since the bony structures shifted with the markers. Conclusion: This method provides a cost-free and simple solution for online tumor tracking for cervical cancer treatment since it is feasible to acquire and export EPID images with fast analysis in real time. This method does not need any extra equipment or deliver extra dose to patients. The online tumor motion information will be very useful to reduce planning margins and improve treatment accuracy, which is particularly important for SBRT treatment with long

  17. Development of a Compton camera for online ion beam range verification via prompt γ detection. Session: HK 12.6 Mo 18:30

    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; Schaart, D. [TU Delft (Netherlands); Castelhano, I. [University of Lisbon, Lisbon (Portugal)

    2015-07-01

    A real-time ion beam verification in hadron-therapy is playing a major role in cancer treatment evaluation. This will make the treatment interuption possible if the planned and actual ion range are mismatched. An imaging system is being developed in Garching aiming to detect prompt γ 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}, 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 study of the Compton camera properties and its individual component are in progress both in the laboratory as well as at the online facilities.

  18. Generalized EPID calibration for in vivo transit dosimetry.

    Science.gov (United States)

    Fidanzio, Andrea; Cilla, Savino; Greco, Francesca; Gargiulo, Laura; Azario, Luigi; Sabatino, Domenico; Piermattei, Angelo

    2011-01-01

    Many researchers are studying new in vivo dosimetry methods based on the use of Elelctronic portal imaging devices (EPIDs) that are simple and efficient in their daily use. However the need of time consuming implementation measurements with solid water phantoms for the in vivo dosimetry implementation can discourage someone in their use. In this paper a procedure has been proposed to calibrate aSi EPIDs for in vivo transit dosimetry. The dosimetric equivalence of three aSi Varian EPIDs has been investigated in terms of signal reproducibility and long term stability, signal linearity with MU and dose per pulse and signal dependence on the field dimensions. The signal reproducibility was within ± 0.5% (2SD), while the long term signal stability has been maintained well within ± 2%. The signal linearity with the monitor units (MU) was within ± 2% and within ± 0.5% for the EPIDs controlled by the IAS 2, and IAS 3 respectively. In particular it was verified that the correction factor for the signal linearity with the monitor units, k(lin), is independent of the beam quality, and the dose per pulse absorbed by the EPID. For 6, 10 and 15 MV photon beams, a generalized set of correlation functions F(TPR,w,L) and empirical factors f(TPR,d,L) as a function of the Tissue Phantom Ratio (TPR), the phantom thickness, w, the square field side, L, and the distance, d, between the phantom mid-plane and the isocentre were determined to reconstruct the isocenter dose. The tolerance levels of the present in vivo dosimetry method ranged between ± 5% and ± 6% depending on the tumor body location. In conclusion, the procedure proposed, that use generalized correlation functions, reduces the effort for the in vivo dosimetry method implementation for those photon beams with TPR within ± 0.3% as respect those here used.

  19. SU-E-J-146: A Research of PET-CT SUV Range for the Online Dose Verification in Carbon Ion Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sun, L; Hu, W [Fudan University Shanghai Cancer Center, Shanghai, Shanghai (China); Moyers, M [Shanghai Proton and Heavy Ion Center, Colton, CA (China); Zhao, J [Shanghai Proton and Heavy Ion Center, Shanghai, Shanghai (China); Hsi, W [Shanghai Proton and Heavy Ion Center, Shanghai (China)

    2015-06-15

    Purpose: Positron-emitting isotope distributions can be used for the image fusion of the carbon ion planning CT and online target verification PETCT, after radiation in the same decay period,the relationship between the same target volume and the SUV value of different every single fraction dose can be found,then the range of SUV for the radiation target could be decided.So this online range also can provide reference for the correlation and consistency in planning target dose verification and evaluation for the clinical trial. Methods: The Rando head phantom can be used as real body,the 10cc cube volume target contouring is done,beam ISO Center depth is 7.6cm and the 90 degree fixed carbon ion beams should be delivered in single fraction effective dose of 2.5GyE,5GyE and 8GyE.After irradiation,390 seconds later the 30 minutes PET-CT scanning is performed,parameters are set to 50Kg virtual weight,0.05mCi activity.MIM Maestro is used for the image processing and fusion,five 16mm diameter SUV spheres have been chosen in the different direction in the target.The average SUV in target for different fraction dose can be found by software. Results: For 10cc volume target,390 seconds decay period,the Single fraction effective dose equal to 2.5Gy,Ethe SUV mean value is 3.42,the relative range is 1.72 to 6.83;Equal to 5GyE,SUV mean value is 9.946,the relative range is 7.016 to 12.54;Equal or above to 8GyE,SUV mean value is 20.496,the relative range is 11.16 to 34.73. Conclusion: Making an evaluation for accuracy of the dose distribution using the SUV range which is from the planning CT with after treatment online PET-CT fusion for the normal single fraction carbon ion treatment is available.Even to the plan which single fraction dose is above 2GyE,in the condition of other parameters all the same,the SUV range is linearly dependent with single fraction dose,so this method also can be used in the hyper-fraction treatment plan.

  20. Effect of translational and rotational errors on complex dose distributions with off-line and on-line position verification

    NARCIS (Netherlands)

    I.M. Lips; U.A. van der Heide; A.N.T.J. Kotte; M. van Vulpen; A. Bel

    2009-01-01

    PURPOSE: To investigate the influence of translational and rotational errors on prostate intensity-modulated radiotherapy (IMRT) with an integrated boost to the tumor and to evaluate the effect of the use of an on-line correction protocol. METHODS AND MATERIALS: For 19 patients, who had been treated

  1. Starting a simple IMRT verification system with Elekta Monaco and Elekta IVIEWGT Planner; Puesta en marca de un sistema sencillo de verificacion de IMRT con Elekta Iviewgt y planificador Elekta Monaco

    Energy Technology Data Exchange (ETDEWEB)

    Ayala Lazaro, R.; Garcia Hernandez, M. J.; Gomez Cores, S.; Jimenez Rojas, R.; Sendon del Rio, J. R.; Polo Cezon, R.; Gomez Calvar, R.

    2013-07-01

    The use of electronic devices of image portal (EPID) is considered fast, effectively and without added cost of verification of static or dynamic IMRT treatments. Its implementation as a verification tool, however, can be quite complicated. Presents an easy way of setting up this system using the method of Lee et to the. and using Elekta MONACO Planner. (Author)

  2. Verification of dose distributions of intensity modulated fields with a portal imaging device; Verificacion de distribuciones de dosis de campos de intensidad modulada con un dispositivo de imagen portal

    Energy Technology Data Exchange (ETDEWEB)

    Perez Moreno, J. M.; Fernandez Leton, P.; Zucca Aparicio, D.; Garcia Ruiz-Zorrilla, J.; Minambres Moro, A.

    2011-07-01

    The electronic portal imaging (EPID) are used for verification of patient positioning. However, the present spatial resolution make them an interesting tool for measuring radiation fields fluences with high dose gradients. We have developed a method to convert the EPID images acquired during the irradiation treatment of a field in a distribution of absorbed dose to water at 5 cm depth and distance from source area (DFS) 95 cm. (Author)

  3. TU-C-BRE-10: A Streamlined Approach to EPID Transit Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Morris, B; Fontenot, J [Louisiana State University, Baton Rouge, LA (United States); Mary Bird Perkins Cancer Center, Baton Rouge, LA (United States)

    2014-06-15

    Purpose: To investigate the feasibility of a simple and efficient transit dosimetry method using the electronic portal imaging device (EPID) for dose delivery error detection and prevention. Methods: In the proposed method, 2D reference transit images are generated for comparison with online images acquired during treatment. Reference transit images are generated by convolving through-air EPID measurements of each field with pixel-specific kernels selected from a library of pre-calculated Monte Carlo pencil kernels of varying radiological thickness. The kernel used for each pixel is selected based on the calculated radiological thickness of the patient along a line joining the pixel and the virtual source. The accuracy of the technique was evaluated in flat homogeneous and heterogeneous plastic water phantoms, a heterogeneous cylindrical phantom, and an anthropomorphic head phantom. Gamma criteria of 3%/3 mm was used to quantify the accuracy of the technique for the various cases. Results: An average of 99.9% and 99.7% of the points in the comparison between the measured and predicted images passed a 3%/3mm gamma for the homogeneous and heterogeneous plastic water phantoms, respectively. 97.1% of the points passed for the analysis of the heterogeneous cylindrical phantom. For the anthropomorphic head phantom, an average of 97.8% of points passed the 3%/3mm gamma criteria for all field sizes. Failures were observed primarily in areas of drastic thickness or material changes and at the edges of the fields. Conclusion: The data suggest that the proposed transit dosimetry method is a feasible approach to in vivo dose monitoring. Future research efforts could include implementation for more complex fields and sensitivity testing of the method to setup errors and changes in anatomy. Oncology Data Systems provided partial funding support but did not participate in the collection or analysis of data.

  4. Using an EPID for patient-specific VMAT quality assurance

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtiari, M.; Kumaraswamy, L.; Bailey, D. W.; Boer, S. de; Malhotra, H. K.; Podgorsak, M. B. [Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 and Department of Physics, State University of New York at Buffalo, Buffalo, New York 14260 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States)

    2011-03-15

    Purpose: A patient-specific quality assurance (QA) method was developed to verify gantry-specific individual multileaf collimator (MLC) apertures (control points) in volumetric modulated arc therapy (VMAT) plans using an electronic portal imaging device (EPID). Methods: VMAT treatment plans were generated in an Eclipse treatment planning system (TPS). DICOM images from a Varian EPID (aS1000) acquired in continuous acquisition mode were used for pretreatment QA. Each cine image file contains the grayscale image of the MLC aperture related to its specific control point and the corresponding gantry angle information. The TPS MLC file of this RapidArc plan contains the leaf positions for all 177 control points (gantry angles). In-house software was developed that interpolates the measured images based on the gantry angle and overlays them with the MLC pattern for all control points. The 38% isointensity line was used to define the edge of the MLC leaves on the portal images. The software generates graphs and tables that provide analysis for the number of mismatched leaf positions for a chosen distance to agreement at each control point and the frequency in which each particular leaf mismatches for the entire arc. Results: Seven patients plans were analyzed using this method. The leaves with the highest mismatched rate were found to be treatment plan dependent. Conclusions: This in-house software can be used to automatically verify the MLC leaf positions for all control points of VMAT plans using cine images acquired by an EPID.

  5. Daily QA of linear accelerators using only EPID and OBI

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Baozhou, E-mail: bsun@radonc.wustl.edu; Goddu, S. Murty; Yaddanapudi, Sridhar; Noel, Camille; Li, Hua; Cai, Bin; Kavanaugh, James; Mutic, Sasa [Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, Campus Box 8224, St. Louis, Missouri 63110 (United States)

    2015-10-15

    Purpose: As treatment delivery becomes more complex, there is a pressing need for robust quality assurance (QA) tools to improve efficiency and comprehensiveness while simultaneously maintaining high accuracy and sensitivity. This work aims to present the hardware and software tools developed for comprehensive QA of linear accelerator (LINAC) using only electronic portal imaging devices (EPIDs) and kV flat panel detectors. Methods: A daily QA phantom, which includes two orthogonally positioned phantoms for QA of MV-beams and kV onboard imaging (OBI) is suspended from the gantry accessory holder to test both geometric and dosimetric components of a LINAC and an OBI. The MV component consists of a 0.5 cm water-equivalent plastic sheet incorporating 11 circular steel plugs for transmission measurements through multiple thicknesses and one resolution plug for MV-image quality testing. The kV-phantom consists of a Leeds phantom (TOR-18 FG phantom supplied by Varian) for testing low and high contrast resolutions. In the developed process, the existing LINAC tools were used to automate daily acquisition of MV and kV images and software tools were developed for simultaneous analysis of these images. A method was developed to derive and evaluate traditional QA parameters from these images [output, flatness, symmetry, uniformity, TPR{sub 20/10}, and positional accuracy of the jaws and multileaf collimators (MLCs)]. The EPID-based daily QA tools were validated by performing measurements on a detuned 6 MV beam to test its effectiveness in detecting errors in output, symmetry, energy, and MLC positions. The developed QA process was clinically commissioned, implemented, and evaluated on a Varian TrueBeam LINAC (Varian Medical System, Palo Alto, CA) over a period of three months. Results: Machine output constancy measured with an EPID (as compared against a calibrated ion-chamber) is shown to be within ±0.5%. Beam symmetry and flatness deviations measured using an EPID and a 2D

  6. Pretreatment Patient Specific Quality Assurance and Gamma Index Variation Study in Gantry Dependent EPID Positions for IMRT Prostate Treatments

    Directory of Open Access Journals (Sweden)

    Siji Cyriac

    2014-01-01

    Full Text Available Pretreatment quality assurance (QA is a major concern in complex radiation therapy treatment plans like intensity modulated radiation therapy (IMRT. Present study considers the variations in gamma index for gantry dependent pretreatment verification and commonly practiced zero gantry angle verifications for ten prostate IMRT plans using two commercial medical linear accelerators (Varian 2300 CD, Varian Clinac iX. Two verification plans (the one with all fields at the actual treatment angles and one with all fields merged to 0 degree gantry angles for all the patients were generated to obtain dose fluence mapping using amorphous silicon electronic portal imaging device (EPID. The gamma index was found depend on gantry angles but the difference between zero and the nonzero treatment angles is in the confidence level for clinical acceptance. The acceptance criteria of gamma method were always satisfied in both cases for two machines and are stable enough to execute the patient specific pretreatment quality assurance at 0 degree gantry angle for prostate IMRTs, where limited number of gantry angles are used.

  7. SU-E-T-582: On-Line Dosimetric Verification of Respiratory Gated Volumetric Modulated Arc Therapy Using the Electronic Portal Imaging Device

    Energy Technology Data Exchange (ETDEWEB)

    Schaly, B; Gaede, S [London Regional Cancer Program, London, ON (United Kingdom); Department of Medical Biophysics, Western University, London, ON (United Kingdom); Department of Oncology, Western University, London, ON (United Kingdom); Xhaferllari, I [London Regional Cancer Program, London, ON (United Kingdom); Department of Medical Biophysics, Western University, London, ON (United Kingdom)

    2015-06-15

    Purpose: To investigate the clinical utility of on-line verification of respiratory gated VMAT dosimetry during treatment. Methods: Portal dose images were acquired during treatment in integrated mode on a Varian TrueBeam (v. 1.6) linear accelerator for gated lung and liver patients that used flattening filtered beams. The source to imager distance (SID) was set to 160 cm to ensure imager clearance in case the isocenter was off midline. Note that acquisition of integrated images resulted in no extra dose to the patient. Fraction 1 was taken as baseline and all portal dose images were compared to that of the baseline, where the gamma comparison and dose difference were used to measure day-to-day exit dose variation. All images were analyzed in the Portal Dosimetry module of Aria (v. 10). The portal imager on the TrueBeam was calibrated by following the instructions for dosimetry calibration in service mode, where we define 1 calibrated unit (CU) equal to 1 Gy for 10×10 cm field size at 100 cm SID. This reference condition was measured frequently to verify imager calibration. Results: The gamma value (3%, 3 mm, 5% threshold) ranged between 92% and 100% for the lung and liver cases studied. The exit dose can vary by as much as 10% of the maximum dose for an individual fraction. The integrated images combined with the information given by the corresponding on-line soft tissue matched cone-beam computed tomography (CBCT) images were useful in explaining dose variation. For gated lung treatment, dose variation was mainly due to the diaphragm position. For gated liver treatment, the dose variation was due to both diaphragm position and weight loss. Conclusion: Integrated images can be useful in verifying dose delivery consistency during respiratory gated VMAT, although the CBCT information is needed to explain dose differences due to anatomical changes.

  8. A Special Issue on the Epididymis & The Proceedings of the Fourth Workshop on the Epididymis (Epid Ⅳ)

    Institute of Scientific and Technical Information of China (English)

    Jo(e)l R. Drevet; Barry T. Hinton; Trevor G. Cooper

    2007-01-01

    @@ The Fourth Epididymis (Epid Ⅳ) Workshop was held between December 4th and 7th 2006 in Chatel-Guyon,France. This was the first European venue for these workshops following Epid Ⅲ held in Charlottesville, Virginia,USA in 2002, Epid Ⅱ held in Newcastle, Australia in 1998 and a one-day meeting (later named Epid Ⅰ) in Hong Kong,China in 1992.

  9. Assessment of a 2D electronic portal imaging devices-based dosimetry algorithm for pretreatment and in-vivo midplane dose verification

    Science.gov (United States)

    Jomehzadeh, Ali; Shokrani, Parvaneh; Mohammadi, Mohammad; Amouheidari, Alireza

    2016-01-01

    Background: The use of electronic portal imaging devices (EPIDs) is a method for the dosimetric verification of radiotherapy plans, both pretreatment and in vivo. The aim of this study is to test a 2D EPID-based dosimetry algorithm for dose verification of some plans inside a homogenous and anthropomorphic phantom and in vivo as well. Materials and Methods: Dose distributions were reconstructed from EPID images using a 2D EPID dosimetry algorithm inside a homogenous slab phantom for a simple 10 × 10 cm2 box technique, 3D conformal (prostate, head-and-neck, and lung), and intensity-modulated radiation therapy (IMRT) prostate plans inside an anthropomorphic (Alderson) phantom and in the patients (one fraction in vivo) for 3D conformal plans (prostate, head-and-neck and lung). Results: The planned and EPID dose difference at the isocenter, on an average, was 1.7% for pretreatment verification and less than 3% for all in vivo plans, except for head-and-neck, which was 3.6%. The mean γ values for a seven-field prostate IMRT plan delivered to the Alderson phantom varied from 0.28 to 0.65. For 3D conformal plans applied for the Alderson phantom, all γ1% values were within the tolerance level for all plans and in both anteroposterior and posteroanterior (AP-PA) beams. Conclusion: The 2D EPID-based dosimetry algorithm provides an accurate method to verify the dose of a simple 10 × 10 cm2 field, in two dimensions, inside a homogenous slab phantom and an IMRT prostate plan, as well as in 3D conformal plans (prostate, head-and-neck, and lung plans) applied using an anthropomorphic phantom and in vivo. However, further investigation to improve the 2D EPID dosimetry algorithm for a head-and-neck case, is necessary. PMID:28028511

  10. Validation of a method for in vivo 3D dose reconstruction for IMRT and VMAT treatments using on-treatment EPID images and a model-based forward-calculation algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Van Uytven, Eric, E-mail: eric.vanuytven@cancercare.mb.ca; Van Beek, Timothy [Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); McCowan, Peter M. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada and Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Chytyk-Praznik, Krista [Medical Physics Department, Nova Scotia Cancer Centre, 5820 University Avenue, Halifax, Nova Scotia B3H 1V7 (Canada); Greer, Peter B. [School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, NSW 2308 (Australia); Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Newcastle, NSW 2298 (Australia); McCurdy, Boyd M. C. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Medical Physics Department, CancerCare Manitoba, 675 McDermot Avenue, Winnipeg, Manitoba R3E 0V9 (Canada); Department of Radiology, University of Manitoba, 820 Sherbrook Street, Winnipeg, Manitoba R3A 1R9 (Canada)

    2015-12-15

    Purpose: Radiation treatments are trending toward delivering higher doses per fraction under stereotactic radiosurgery and hypofractionated treatment regimens. There is a need for accurate 3D in vivo patient dose verification using electronic portal imaging device (EPID) measurements. This work presents a model-based technique to compute full three-dimensional patient dose reconstructed from on-treatment EPID portal images (i.e., transmission images). Methods: EPID dose is converted to incident fluence entering the patient using a series of steps which include converting measured EPID dose to fluence at the detector plane and then back-projecting the primary source component of the EPID fluence upstream of the patient. Incident fluence is then recombined with predicted extra-focal fluence and used to calculate 3D patient dose via a collapsed-cone convolution method. This method is implemented in an iterative manner, although in practice it provides accurate results in a single iteration. The robustness of the dose reconstruction technique is demonstrated with several simple slab phantom and nine anthropomorphic phantom cases. Prostate, head and neck, and lung treatments are all included as well as a range of delivery techniques including VMAT and dynamic intensity modulated radiation therapy (IMRT). Results: Results indicate that the patient dose reconstruction algorithm compares well with treatment planning system computed doses for controlled test situations. For simple phantom and square field tests, agreement was excellent with a 2%/2 mm 3D chi pass rate ≥98.9%. On anthropomorphic phantoms, the 2%/2 mm 3D chi pass rates ranged from 79.9% to 99.9% in the planning target volume (PTV) region and 96.5% to 100% in the low dose region (>20% of prescription, excluding PTV and skin build-up region). Conclusions: An algorithm to reconstruct delivered patient 3D doses from EPID exit dosimetry measurements was presented. The method was applied to phantom and patient

  11. Characterization of a new transmission detector for patient individualized online plan verification and its influence on 6MV X-ray beam characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Thoelking, Johannes; Sekar, Yuvaraj; Fleckenstein, Jens; Lohr, Frank; Wenz, Frederik; Wertz, Hansjoerg [Heidelberg Univ., University Medical Center Mannheim (Germany). Dept. of Radiation Oncology

    2016-11-01

    Online verification and 3D dose reconstruction on daily patient anatomy have the potential to improve treatment delivery, accuracy and safety. One possible implementation is to recalculate dose based on online fluence measurements with a transmission detector (TD) attached to the linac. This study provides a detailed analysis of the influence of a new TD on treatment beam characteristics. The influence of the new TD on surface dose was evaluated by measurements with an Advanced Markus Chamber (Adv-MC) in the build-up region. Based on Monte Carlo simulations, correction factors were determined to scale down the over-response of the Adv-MC close to the surface. To analyze the effects beyond d{sub max} percentage depth dose (PDD), lateral profiles and transmission measurements were performed. All measurements were carried out for various field sizes and different SSDs. Additionally, 5 IMRT-plans (head and neck, prostate, thorax) and 2 manually created test cases (3 x 3 cm{sup 2} fields with different dose levels, sweeping gap) were measured to investigate the influence of the TD on clinical treatment plans. To investigate the performance of the TD, dose linearity as well as dose rate dependency measurements were performed. With the TD inside the beam an increase in surface dose was observed depending on SSD and field size (maximum of +11%, SSD = 80 cm, field size = 30 x 30 cm{sup 2}). Beyond d{sub max} the influence of the TD on PDDs was below 1%. The measurements showed that the transmission factor depends slightly on the field size (0.893-0.921 for 5 x 5 cm{sup 2} to 30 x 30 cm{sup 2}). However, the evaluation of clinical IMRT-plans measured with and without the TD showed good agreement after using a single transmission factor (γ{sub (2%/2mm)} > 97%, δ{sub ±3%} >95%). Furthermore, the response of TD was found to be linear and dose rate independent (maximum difference <0.5% compared to reference measurements). When placed in the path of the beam, the TD introduced

  12. The radiation isocenter verification using an electronic system of image portal; Verificacion del isocentro de radiacion utilizando un sistema electronico de imagen portal

    Energy Technology Data Exchange (ETDEWEB)

    Merino Gestoso, J. A.; Portas Ferradas, B. C.; Rosa Menendez, P.; Chapel Gomez, M. L.; Fernandez Cerezo, S.; Vazquez Varela, P.

    2013-07-01

    In this paper we present a procedure optimized for verification the isocenter of radiation with respect to the rotation of the gantry and the turn isocentric table of two accelerators SIEMENS, ONCOR and ARTISTE with a mannequin developed in our service and analyzing the images acquired with the EPID from each of the teams. (Author)

  13. Virtual patient 3D dose reconstruction using in air EPID measurements and a back-projection algorithm for IMRT and VMAT treatments.

    Science.gov (United States)

    Olaciregui-Ruiz, Igor; Rozendaal, Roel; van Oers, René F M; Mijnheer, Ben; Mans, Anton

    2017-05-01

    At our institute, a transit back-projection algorithm is used clinically to reconstruct in vivo patient and in phantom 3D dose distributions using EPID measurements behind a patient or a polystyrene slab phantom, respectively. In this study, an extension to this algorithm is presented whereby in air EPID measurements are used in combination with CT data to reconstruct 'virtual' 3D dose distributions. By combining virtual and in vivo patient verification data for the same treatment, patient-related errors can be separated from machine, planning and model errors. The virtual back-projection algorithm is described and verified against the transit algorithm with measurements made behind a slab phantom, against dose measurements made with an ionization chamber and with the OCTAVIUS 4D system, as well as against TPS patient data. Virtual and in vivo patient dose verification results are also compared. Virtual dose reconstructions agree within 1% with ionization chamber measurements. The average γ-pass rate values (3% global dose/3mm) in the 3D dose comparison with the OCTAVIUS 4D system and the TPS patient data are 98.5±1.9%(1SD) and 97.1±2.9%(1SD), respectively. For virtual patient dose reconstructions, the differences with the TPS in median dose to the PTV remain within 4%. Virtual patient dose reconstruction makes pre-treatment verification based on deviations of DVH parameters feasible and eliminates the need for phantom positioning and re-planning. Virtual patient dose reconstructions have additional value in the inspection of in vivo deviations, particularly in situations where CBCT data is not available (or not conclusive). Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. Dose-to-water conversion for the backscatter-shielded EPID: A frame-based method to correct for EPID energy response to MLC transmitted radiation

    Energy Technology Data Exchange (ETDEWEB)

    Zwan, Benjamin J., E-mail: benjamin.zwan@uon.edu.au; O’Connor, Daryl J. [School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales 2308 (Australia); King, Brian W. [Department of Radiation Oncology, Massey Cancer Center, Virginia Commonwealth University Health System, Richmond, Virginia 23298 (United States); Greer, Peter B. [School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales 2308, Australia and Department of Radiation Oncology, Calvary Mater Newcastle Hospital, Newcastle, New South Wales 2310 (Australia)

    2014-08-15

    Purpose: To develop a frame-by-frame correction for the energy response of amorphous silicon electronic portal imaging devices (a-Si EPIDs) to radiation that has transmitted through the multileaf collimator (MLC) and to integrate this correction into the backscatter shielded EPID (BSS-EPID) dose-to-water conversion model. Methods: Individual EPID frames were acquired using a Varian frame grabber and iTools acquisition software then processed using in-house software developed inMATLAB. For each EPID image frame, the region below the MLC leaves was identified and all pixels in this region were multiplied by a factor of 1.3 to correct for the under-response of the imager to MLC transmitted radiation. The corrected frames were then summed to form a corrected integrated EPID image. This correction was implemented as an initial step in the BSS-EPID dose-to-water conversion model which was then used to compute dose planes in a water phantom for 35 IMRT fields. The calculated dose planes, with and without the proposed MLC transmission correction, were compared to measurements in solid water using a two-dimensional diode array. Results: It was observed that the integration of the MLC transmission correction into the BSS-EPID dose model improved agreement between modeled and measured dose planes. In particular, the MLC correction produced higher pass rates for almost all Head and Neck fields tested, yielding an average pass rate of 99.8% for 2%/2 mm criteria. A two-sample independentt-test and fisher F-test were used to show that the MLC transmission correction resulted in a statistically significant reduction in the mean and the standard deviation of the gamma values, respectively, to give a more accurate and consistent dose-to-water conversion. Conclusions: The frame-by-frame MLC transmission response correction was shown to improve the accuracy and reduce the variability of the BSS-EPID dose-to-water conversion model. The correction may be applied as a preprocessing step

  15. Step-and-Shoot IMRT by Siemens Beams: An EPID Dosimetry Verification During Treatment.

    Science.gov (United States)

    Russo, M; Piermattei, A; Greco, F; Azario, L; Orlandini, L; Zucca, S; Cilla, S; Menna, S; Grusio, M; Chiatti, L; Fidanzio, A

    2016-08-01

    This work reports the extension of a semiempirical method based on the correlation ratios to convert electronic portal imaging devices transit signals into in vivo doses for the step-and-shoot intensity-modulated radiotherapy Siemens beams. The dose reconstructed at the isocenter point Diso, compared to the planned dose, Diso,TPS, and a γ-analysis between 2-dimensional electronic portal imaging device images obtained day to day, seems to supply a practical method to verify the beam delivery reproducibility. The electronic portal imaging device images were obtained by the superposition of many segment fields, and the algorithm for the Diso reconstruction for intensity-modulated radiotherapy step and shoot was formulated using a set of simulated intensity-modulated radiotherapy beams. Moreover, the in vivo dose-dedicated software was integrated with the record and verify system of the centers. Three radiotherapy centers applied the in vivo dose procedure at 30 clinical intensity-modulated radiotherapy treatments, each one obtained with 5 or 7 beams, and planned for patients undergoing radiotherapy for prostatic tumors. Each treatment beam was checked 5 times, obtaining 900 tests of the ratios R = Diso/Diso,TPS. The average R value was equal to 1.002 ± 0.056 (2 standard deviation), while the mean R value for each patient was well within 5%, once the causes of errors were removed. The γ-analysis of the electronic portal imaging device images, with 3% 3 mm acceptance criteria, showed 90% of the tests with Pγ Fisica Nucleare. © The Author(s) 2015.

  16. An improved Monte-Carlo model of the Varian EPID separating support arm and rear-housing backscatter

    Science.gov (United States)

    Monville, M. E.; Kuncic, Z.; Greer, P. B.

    2014-03-01

    Previous investigators of EPID dosimetric properties have ascribed the backscatter, that contaminates dosimetric EPID images, to its supporting arm. Accordingly, Monte-Carlo (MC) EPID models have approximated the backscatter signal from the layers under the detector and the robotic support arm using either uniform or non-uniform solid water slabs, or through convolutions with back-scatter kernels. The aim of this work is to improve the existent MC models by measuring and modelling the separate backscatter contributions of the robotic arm and the rear plastic housing of the EPID. The EPID plastic housing is non-uniform with a 11.9 cm wide indented section that runs across the cross-plane direction in the superior half of the EPID which is 1.75 cm closer to the EPID sensitive layer than the rest of the housing. The thickness of the plastic housing is 0.5 cm. Experiments were performed with and without the housing present by removing all components of the EPID from the housing. The robotic support arm was not present for these measurements. A MC model of the linear accelerator and the EPID was modified to include the rear-housing indentation and results compared to the measurement. The rear housing was found to contribute a maximum of 3% additional signal. The rear housing contribution to the image is non-uniform in the in-plane direction with 2% asymmetry across the central 20 cm of an image irradiating the entire detector. The MC model was able to reproduce this non-uniform contribution. The EPID rear housing contributes a non-uniform backscatter component to the EPID image, which has not been previously characterized. This has been incorporated into an improved MC model of the EPID.

  17. TH-E-17A-10: Markerless Lung Tumor Tracking Based On Beams Eye View EPID Images

    Energy Technology Data Exchange (ETDEWEB)

    Chiu, T; Kearney, V; Liu, H; Jiang, L; Foster, R; Mao, W [UT Southwestern Medical Center, Dallas, Texas (United States); Rozario, T; Bereg, S [University of Texas at Dallas, Richardson, Texas (United States); Klash, S [Premier Cancer Centers, Dallas, TX (United States)

    2014-06-15

    Purpose: Dynamic tumor tracking or motion compensation techniques have proposed to modify beam delivery following lung tumor motion on the flight. Conventional treatment plan QA could be performed in advance since every delivery may be different. Markerless lung tumor tracking using beams eye view EPID images provides a best treatment evaluation mechanism. The purpose of this study is to improve the accuracy of the online markerless lung tumor motion tracking method. Methods: The lung tumor could be located on every frame of MV images during radiation therapy treatment by comparing with corresponding digitally reconstructed radiograph (DRR). A kV-MV CT corresponding curve is applied on planning kV CT to generate MV CT images for patients in order to enhance the similarity between DRRs and MV treatment images. This kV-MV CT corresponding curve was obtained by scanning a same CT electron density phantom by a kV CT scanner and MV scanner (Tomotherapy) or MV CBCT. Two sets of MV DRRs were then generated for tumor and anatomy without tumor as the references to tracking the tumor on beams eye view EPID images. Results: Phantom studies were performed on a Varian TrueBeam linac. MV treatment images were acquired continuously during each treatment beam delivery at 12 gantry angles by iTools. Markerless tumor tracking was applied with DRRs generated from simulated MVCT. Tumors were tracked on every frame of images and compared with expected positions based on programed phantom motion. It was found that the average tracking error were 2.3 mm. Conclusion: This algorithm is capable of detecting lung tumors at complicated environment without implanting markers. It should be noted that the CT data has a slice thickness of 3 mm. This shows the statistical accuracy is better than the spatial accuracy. This project has been supported by a Varian Research Grant.

  18. Tracking tumor boundary in MV-EPID images without implanted markers: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaoyong, E-mail: xiaoyong@ieee.org; Homma, Noriyasu, E-mail: homma@ieee.org [Department of Radiological Imaging and Informatics, Tohoku University Graduate School of Medicine, Sendai 980-8579 (Japan); Ichiji, Kei, E-mail: ichiji@yoshizawa.ecei.tohoku.ac.jp [Research Institute of Electrical Communication, Tohoku University, Sendai 980-8579 (Japan); Takai, Yoshihiro, E-mail: y-takai@cc.hirosaki-u.ac.jp [Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562 (Japan); Yoshizawa, Makoto, E-mail: yoshizawa@yoshizawa.ecei.tohoku.ac.jp [Research Division on Advanced Information Technology, Cyberscience Center, Tohoku University, Sendai 980-8579 (Japan)

    2015-05-15

    Purpose: To develop a markerless tracking algorithm to track the tumor boundary in megavoltage (MV)-electronic portal imaging device (EPID) images for image-guided radiation therapy. Methods: A level set method (LSM)-based algorithm is developed to track tumor boundary in EPID image sequences. Given an EPID image sequence, an initial curve is manually specified in the first frame. Driven by a region-scalable energy fitting function, the initial curve automatically evolves toward the tumor boundary and stops on the desired boundary while the energy function reaches its minimum. For the subsequent frames, the tracking algorithm updates the initial curve by using the tracking result in the previous frame and reuses the LSM to detect the tumor boundary in the subsequent frame so that the tracking processing can be continued without user intervention. The tracking algorithm is tested on three image datasets, including a 4-D phantom EPID image sequence, four digitally deformable phantom image sequences with different noise levels, and four clinical EPID image sequences acquired in lung cancer treatment. The tracking accuracy is evaluated based on two metrics: centroid localization error (CLE) and volume overlap index (VOI) between the tracking result and the ground truth. Results: For the 4-D phantom image sequence, the CLE is 0.23 ± 0.20 mm, and VOI is 95.6% ± 0.2%. For the digital phantom image sequences, the total CLE and VOI are 0.11 ± 0.08 mm and 96.7% ± 0.7%, respectively. In addition, for the clinical EPID image sequences, the proposed algorithm achieves 0.32 ± 0.77 mm in the CLE and 72.1% ± 5.5% in the VOI. These results demonstrate the effectiveness of the authors’ proposed method both in tumor localization and boundary tracking in EPID images. In addition, compared with two existing tracking algorithms, the proposed method achieves a higher accuracy in tumor localization. Conclusions: In this paper, the authors presented a feasibility study of tracking

  19. Commissioning of Portal Dosimetry and characterization of an EPID; Comissionamento de Portal Dosimetry e caracterizacao de EPID

    Energy Technology Data Exchange (ETDEWEB)

    Olbi, D.S.; Sales, C.P. [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina; Nakandakari, M.V.N., E-mail: diego.olbi@hc.fm.usp.br [Instituto do Cancer do Estado de Sao Paulo, SP (Brazil). Servico de Radioterapia

    2016-07-01

    The development of technologies compensator blocks, MLC, high dose rate accelerators, treatment planning systems, among others, permitted that new treatment techniques in radiotherapy were created. Such techniques have the capacity to modulate radiation beam fluency (IMRT, VMAT), or to deliver high doses in few fractions or unique fractions (SRS). Following the same tendency, quality control of planning became more complex. It is necessary to evaluate the fluency delivered by the accelerator. Its levels of does and its spatial distribution should co-occur with the fluency calculated by TPS. Acquisition of new detector devices in quality control of treatments is fundamental to apply techniques. Portal Vision is a device EPID has the capacity to operate either in image mode or dosimetry mode, with the allowance of Portal Dosimetry. To evaluated planning in IMRT, the device is irradiated using planning e, therefore, the fluency measured is compared with calculated fluency, through gamma analysis. The aim of this work was to perform tests of commissioning of this device. (author)

  20. A comprehensive study of the mechanical performance of gantry, EPID and the MLC assembly in Elekta linacs during gantry rotation

    DEFF Research Database (Denmark)

    Rowshanfarzad, P; Lynggaard Riis, Hans; Zimmermann, S J

    2015-01-01

    OBJECTIVE: In radiotherapy treatments, it is crucial to monitor the performance of linear accelerator (linac) components, including gantry, collimation system and electronic portal imaging device (EPID) during arc deliveries. In this study, a simple EPID-based measurement method is suggested...... bank assembly owing to linac rotation were separately investigated by acquisition of 37 EPID images of a simple phantom with 5 ball bearings at various gantry angles. A fast and robust software package was developed for automated analysis of the image data. Nine Elekta AB (Stockholm, Sweden) linacs...... of different models and number of years in service were investigated. RESULTS: The average EPID sag was within 2 mm for all tested linacs. Some machines showed >1-mm gantry sag. Changes in the SDD values were within 1.3 cm. EPID skewness and tilt values were

  1. Clinical validation of an in-house EPID dosimetry system for IMRT QA at the Prince of Wales Hospital

    Science.gov (United States)

    Tyler, M.; Vial, P.; Metcalfe, P.; Downes, S.

    2013-06-01

    In this study a simple method using standard flood-field corrected Electronic Portal Imaging Device (EPID) images for routine Intensity Modulated Radiation Therapy (IMRT) Quality Assurance (QA) was investigated. The EPID QA system was designed and tested on a Siemens Oncor Impression linear accelerator with an OptiVue 1000ST EPID panel (Siemens Medical Solutions USA, Inc, USA) and an Elekta Axesse linear accelerator with an iViewGT EPID (Elekta AB, Sweden) for 6 and 10 MV IMRT fields with Step-and-Shoot and dynamic-MLC delivery. Two different planning systems were used for patient IMRT field generation for comparison with the measured EPID fluences. All measured IMRT plans had >95% agreement to the planning fluences (using 3 cGy / 3 mm Gamma Criteria) and were comparable to the pass-rates calculated using a 2-D diode array dosimeter.

  2. An Assessment Method for On-line Verification of Relay Protection Setting%一种继电保护定值在线校核评估方法

    Institute of Scientific and Technical Information of China (English)

    张海翔; 吕飞鹏; 廖小君

    2013-01-01

    In order to make the verification of relay protection setting more scientific and effective, a new method for on-line verification of relay protection setting based on protection importance is presented. Firstly, the component outage models are developed. Secondly, the related outage event tree is constructed by using the event tree analysis method, thus resulting in obtaining different system states. Finally, the order of line importance and protection importance indicators is found by calculation based on the risk theory. According to the descending order of protection importance, on-line verifying the protection of values can be conducted. It is shown by IEEE 9-bus system that the method is feasible and correct.%为了使继电保护定值校核工作更加科学有效,提出了基于保护重要度的继电保护定值在线校核新方法.首先建立了元件停运模型;然后利用事件树分析法构造相关停运事件树,从而得到不同的系统状态;最后基于风险理论计算出线路和保护的重要度指标排序,根据保护重要度降序排序可进行在线校核保护定值.通过IEEE 9节点系统的分析,验证了该方法的可行性及正确性.

  3. Necrólisis epidérmica tóxica

    OpenAIRE

    Manuel Díaz de León-Ponce; Armando Alberto Moreno-Santillán; Jorge Iván González-Díaz; Jesús Carlos Briones-Garduño

    2006-01-01

    Introducción: la necrólisis epidérmica tóxica es un padecimiento que evoluciona con elevada mortalidad. El objetivo fue mostrar la utilidad de un tratamiento no convencional para la necrólisis epidérmica tóxica, dado que con los tratamientos convencionales la mortalidad es mayor de 50 % y con el tratamiento propuesto fue de 0 %. Material y métodos: estudio prospectivo y descriptivo que incluyó 12 individuos tratados en el Hospital General y el Hospital de Especialidades, Centro Médico Naciona...

  4. On the evaluation of patient specific IMRT QA using EPID, dynalog files and patient anatomy

    Directory of Open Access Journals (Sweden)

    Dewayne Lee Defoor

    2014-03-01

    Full Text Available Purpose: This research, investigates the viability of using the Electronic portal imaging device (EPID coupled with the treatment planning system (TPS, to calculate the doses delivered and verify agreement with the treatment plan. The results of QA analysis using the EPID, Delta4 and fluence calculations using the multi-leaf collimator (MLC dynalog files on 10 IMRT patients are presented in this study.Methods: EPID Fluence Images in integrated mode and Dynalog files for each field were acquired for 10 IMRT (6MV patients and processed through an in house MatLab program to create an opening density matrix (ODM which was used as the input fluence for dose calculation with the TPS (Pinnacle3, Philips. The EPID used in this study was the aSi1000 Varian on a Novalis TX linac equipped with high definition MLC. The resulting dose distributions were then exported to VeriSoft (PTW where a 3D gamma was calculated using 3 mm-3% criteria. The Scandidos Delta4 phantom was also used to measure a 2D dose distribution for all 10 patients and a 2D gamma was calculated for each patient using the Delta4 software.Results: The average 3D gamma for all 10 patients using the EPID images was 98.2% ± 2.6%. The average 3D gamma using the dynalog files was 94.6% ± 4.9%. The average 2D gamma from the Delta4 was 98.1% ± 2.5%. The minimum 3D gamma for the EPID and dynalog reconstructed dose distributions was found on the same patient which had a very large PTV, requiring the jaws to open to the maximum field size. Conclusion: Use of the EPID, combined with a TPS is a viable method for QA of IMRT plans. A larger ODM size can be implemented to accommodate larger field sizes. An adaptation of this process to Volumetric Arc Therapy (VMAT is currently under way.-----------------------------Cite this article as: Defoor D, Mavroidis P, Quino L, Gutierrez A, Papanikolaou N, Stathakis S. On the evaluation of patient specific IMRT QA using EPID, dynalog files and patient anatomy

  5. Necrolisis epidérmica tóxica y lupus eritematoso sistémico

    Directory of Open Access Journals (Sweden)

    Amauri Lázaro Noda Albelo

    Full Text Available La necrolisis epidérmica tóxica es el resultado de una reacción mucocutánea aguda severa. La frecuencia con que ocurre esta enfermedad es superior en estados patológicos, cuando existe una respuesta inmune «aberrante», incluida enfermedad injerto contra huésped, cáncer, infección por VIH y enfermedades autoinmunes. Se describe un caso que cumple con los criterios diagnósticos de lupus eritematoso sistémico y necrolisis epidérmica tóxica.

  6. 75 FR 4101 - Enterprise Income Verification (EIV) System User Access Authorization Form and Rules of Behavior...

    Science.gov (United States)

    2010-01-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT Enterprise Income Verification (EIV) System User Access Authorization Form and Rules.... This notice also lists the following information: Title of Proposal: Enterprise Income Verification...

  7. Cine EPID evaluation of two non-commercial techniques for DIBH

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Christopher; Urribarri, Jaime; Cail, Daniel; Rottmann, Joerg; Mishra, Pankaj; Lingos, Tatiana; Niedermayr, Thomas; Berbeco, Ross, E-mail: rberbeco@lroc.harvard.edu [Brigham and Women' s Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2014-02-15

    Purpose: To evaluate the efficacy of two noncommercial techniques for deep inspiration breathhold (DIBH) treatment of left-sided breast cancer (LSBC) usingcine electronic portal imaging device (EPID) images. Methods: 23 875 EPID images of 65 patients treated for LSBC at two different cancer treatment centers were retrieved. At the Milford Regional Cancer Center, DIBH stability was maintained by visual alignment of inroom lasers and patient skin tattoos (TAT). At the South Shore Hospital, a distance-measuring laser device (RTSSD) was implemented. For both centers,cine EPID images were acquired at least once per week during beam-on. Chest wall position relative to image boundary was measured and tracked over the course of treatment for every patient and treatment fraction for which data were acquired. Results: Median intrabeam chest motion was 0.31 mm for the TAT method and 0.37 mm for the RTSSD method. The maximum excursions exceeded our treatment protocol threshold of 3 mm in 0.3% of cases (TAT) and 1.2% of cases (RTSSD). The authors did not observe a clinically significant difference between the two datasets. Conclusions: Both noncommercial techniques for monitoring the DIBH location provided DIBH stability within the predetermined treatment protocol parameters (<3 mm). The intreatment imaging offered by the EPID operating incine mode facilitates retrospective analysis and validation of both techniques.

  8. Cine EPID evaluation of two non-commercial techniques for DIBH

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Christopher; Urribarri, Jaime; Cail, Daniel; Rottmann, Joerg; Mishra, Pankaj; Lingos, Tatiana; Niedermayr, Thomas; Berbeco, Ross, E-mail: rberbeco@lroc.harvard.edu [Brigham and Women' s Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2014-02-15

    Purpose: To evaluate the efficacy of two noncommercial techniques for deep inspiration breathhold (DIBH) treatment of left-sided breast cancer (LSBC) usingcine electronic portal imaging device (EPID) images. Methods: 23 875 EPID images of 65 patients treated for LSBC at two different cancer treatment centers were retrieved. At the Milford Regional Cancer Center, DIBH stability was maintained by visual alignment of inroom lasers and patient skin tattoos (TAT). At the South Shore Hospital, a distance-measuring laser device (RTSSD) was implemented. For both centers,cine EPID images were acquired at least once per week during beam-on. Chest wall position relative to image boundary was measured and tracked over the course of treatment for every patient and treatment fraction for which data were acquired. Results: Median intrabeam chest motion was 0.31 mm for the TAT method and 0.37 mm for the RTSSD method. The maximum excursions exceeded our treatment protocol threshold of 3 mm in 0.3% of cases (TAT) and 1.2% of cases (RTSSD). The authors did not observe a clinically significant difference between the two datasets. Conclusions: Both noncommercial techniques for monitoring the DIBH location provided DIBH stability within the predetermined treatment protocol parameters (<3 mm). The intreatment imaging offered by the EPID operating incine mode facilitates retrospective analysis and validation of both techniques.

  9. Poster — Thur Eve — 25: Sensitivity to inhomogeneities for an in-vivo EPID dosimetry method

    Energy Technology Data Exchange (ETDEWEB)

    Peca, Stefano; Brown, Derek [Department of Medical Physics, Tom Baker Cancer Centre, Calgary AB (Canada); Department of Physics and Astronomy, University of Calgary, Calgary, AB (Canada)

    2014-08-15

    Introduction: The electronic portal imaging device (EPID) has the potential to be used for in vivo dosimetry during radiotherapy as an additional dose delivery check. We recently proposed a simple method of using the EPID for 2D-IVD based on correlation ratios. In this work we have investigated the sensitivity of our EPID-IVD to inhomogeneities. Methods: We used slab phantoms that simulate water, bone, and lung, arranged in various geometries. To simulate body contours non-orthogonal to the field, we used a water wedge. CT data of these phantoms was imported into MATLAB, in conjunction with EPID images acquired during irradiation, to calculate dose inside the phantom in isocenter plane. Each phantom was irradiated using a linear accelerator while images were acquired with the EPID (cine mode). Comparisons between EPID-calculated and TPS dose maps were: pixel-by-pixel dose difference, and 3%,3mm gamma evaluation. Results: In the homogeneous case, CAX dose difference was <1%, and 3%,3mm gamma analysis yielded 99% of points with gamma<1. For the inhomogeneous phantoms, agreement decreased with increasing inhomogeneity reaching up to 10% CAX dose difference with 10cm of lung. Results from the water wedge phantom suggest that the EPID-calculated dose can account for surface irregularities of approximately ±3cm. Conclusions: The EPID-based IVD investigated has limitations in the presence of large inhomogeneities. Nonetheless, CAX doses never differed by >15% from the TPS. This suggests that this EPID-IVD is capable of detecting gross dose delivery errors even in the presence of inhomogeneities, supporting its utility as an additional patient safety device.

  10. Preservación de espermatozoides de la cola del epidídimo bovino en condiciones de campo

    OpenAIRE

    Durán, J. P.; Espinoza, J. R.; Cabrera, N. C.; Aponte, P. M.; Universidad de Cuenca; Dirección de Investigación de la Universidad de Cuenca; DIUC

    2015-01-01

    La cola del epidídimo constituye un reservorio de espermatozoides que han alcanzado la madurez biológica a través de su trayecto por el largo conducto del epidídimo (Robaire y Hinton, 2014). Los espermatozoides de esta reserva epididimaria pueden obtenerse postmortem o a través de biopsias y utilizarse con fines reproductivos (Albers y Barrios, 2011). El presente trabajo tiene como objetivo principal probar algunas condiciones iniciales de manejo de espermatozoides de la cola del epidídimo de...

  11. A novel EPID design for enhanced contrast and detective quantum efficiency

    Science.gov (United States)

    Rottmann, Joerg; Morf, Daniel; Fueglistaller, Rony; Zentai, George; Star-Lack, Josh; Berbeco, Ross

    2016-09-01

    Beams-eye-view imaging applications such as real-time soft-tissue motion estimation are hindered by the inherently low image contrast of electronic portal imaging devices (EPID) currently available for clinical use. We introduce and characterize a novel EPID design that provides substantially increased detective quantum efficiency (DQE), contrast-to-noise ratio (CNR) and sensitivity without degradation in spatial resolution. The prototype design features a stack of four conventional EPID layers combined with low noise integrated readout electronics. Each layer consists of a copper plate, a scintillator (\\text{G}{{\\text{d}}2}{{\\text{O}}2}{{\\text{S}}{}}\\text{:Tb} ) and a photodiode/TFT-switch (aSi:H). We characterize the prototype’s signal response to a 6 MV photon beam in terms of modulation transfer function (MTF), DQE and CNR. The presampled MTF is estimated using a slanted slit technique, the DQE is calculated from measured normalized noise power spectra (nNPS) and the MTF and CNR is estimated using a Las Vegas contrast phantom. The prototype has been designed and built to be interchangeable with the current clinical EPID on the Varian TrueBeam platform (AS-1200) in terms of size and data output specifications. Performance evaluation is conducted in absolute values as well as in relative terms using the Varian AS-1200 EPID as a reference detector. A fivefold increase of DQE(0) to about 6.7% was observed by using the four-layered design versus the AS-1200 reference detector. No substantial differences are observed between each layer’s individual MTF and the one for all four layers operating combined indicating that defocusing due to beam divergence is negligible. Also, using four layers instead of one increases the signal to noise ratio by a factor of 1.7.

  12. Development and Multi-laboratory Verification of US EPA Method 543 for the Analysis of Drinking Water Contaminants by Online Solid Phase Extraction-LC-MS-MS.

    Science.gov (United States)

    Shoemaker, Jody A

    2016-06-26

    A drinking water method for seven pesticides and pesticide degradates is presented that addresses the occurrence monitoring needs of the US Environmental Protection Agency (EPA) for a future Unregulated Contaminant Monitoring Regulation (UCMR). The method employs online solid phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS-MS). Online SPE-LC-MS-MS has the potential to offer cost-effective, faster, more sensitive and more rugged methods than the traditional offline SPE approach due to complete automation of the SPE process, as well as seamless integration with the LC-MS-MS system. The method uses 2-chloroacetamide, ascorbic acid and Trizma to preserve the drinking water samples for up to 28 days. The mean recoveries in drinking water (from a surface water source) fortified with method analytes are 87.1-112% with relative standard deviations of requirements for sample collection and storage, precision, accuracy, and sensitivity.

  13. SU-E-T-363: Error Detection Comparison of EPID and MLC Log File Based IMRT QA Systems

    Energy Technology Data Exchange (ETDEWEB)

    Defoor, D; Obeidat, M; Linden, P; Kirby, N; Papanikolaou, N; Stathakis, S [University of Texas Health Science Center at San Antonio, San Antonio, TX (United States); Mavroidis, P [University of North Carolina, Chapel Hill, NC (United States)

    2015-06-15

    Purpose: In this study we will compare the ability of three QA methods (Delta4, MU-EPID, Dynalog QA) to detect specific errors. Methods: A Varian Novalis Tx with a HD120 MLC and aS1000 Electronic Portal Imaging Device (EPID) was used in our study. Multi-leaf collimator (MLC) errors, gantry angle and dose errors were introduced into 5 volumetric arc therapy (VMAT) plans. 3D dose distributions calculated with data from the EPID and Dynalog QA methods were compared with the planned dose distribution. The gamma passing percentages as well as percentage error of planning target volume (PTV) dose were used for passing determination. Baselines for gamma passing percentages and PTV dose were established by measuring the original plan 5 times consecutively. Standard passing thresholds as well as thresholds derived from receiver operator characteristic (ROC) analysis and 2 standard deviation (SD) criteria were used. Results: When applying the standard 95% pass rate at 3%/3mm gamma analysis 14, 21 and 8 of 30 errors were detected by the Delta4, MU-EPID and Dynalog QA methods respectively. Thresholds set at 2 SD from our base line measurements resulted in the detection of 18, 9 and 14 of 30 errors for the Delta4, MU-EPID and Dynalog QA methods respectively. When using D2 of the PTV as a metric the Dynalog QA detected 20 of 30 errors while the EPID method detected 14 of 30 errors. Using D98 of the PTV, Dynalog QA detected 13 of 30 while the EPID detected 3 of 30 errors. Conclusion: Although MU-EPID detected the most errors at the standard 95% cutoff it also produced the most false detections in the baseline data. The Dynalog QA was the most effective when the ROC adjusted passing threshold was used. D2 was more effective as a metric for detecting errors than D98.

  14. State Online Query System (SOLQ)

    Data.gov (United States)

    Social Security Administration — Designed specifically for State Human Service agencies, SOLQ allows States real-time online access to SSA's SSN verification service and, if permitted, retrieval of...

  15. 76 FR 60112 - Consent Based Social Security Number Verification (CBSV) Service

    Science.gov (United States)

    2011-09-28

    ... service, visit our Internet site, Social Security Online, at http://www.socialsecurity.gov . Gerard R... From the Federal Register Online via the Government Publishing Office SOCIAL SECURITY ADMINISTRATION Consent Based Social Security Number Verification (CBSV) Service AGENCY: Social...

  16. 78 FR 56266 - Consent Based Social Security Number Verification (CBSV) Service

    Science.gov (United States)

    2013-09-12

    ...-6401, , for more information about the CBSV service, visit our Internet site, Social Security Online... From the Federal Register Online via the Government Publishing Office SOCIAL SECURITY ADMINISTRATION Consent Based Social Security Number Verification (CBSV) Service AGENCY: Social...

  17. Swarm Verification

    Science.gov (United States)

    Holzmann, Gerard J.; Joshi, Rajeev; Groce, Alex

    2008-01-01

    Reportedly, supercomputer designer Seymour Cray once said that he would sooner use two strong oxen to plow a field than a thousand chickens. Although this is undoubtedly wise when it comes to plowing a field, it is not so clear for other types of tasks. Model checking problems are of the proverbial "search the needle in a haystack" type. Such problems can often be parallelized easily. Alas, none of the usual divide and conquer methods can be used to parallelize the working of a model checker. Given that it has become easier than ever to gain access to large numbers of computers to perform even routine tasks it is becoming more and more attractive to find alternate ways to use these resources to speed up model checking tasks. This paper describes one such method, called swarm verification.

  18. SU-E-T-252: On the Evaluation of Patient Specific IMRT QA Using EPID, Dynalog Files and Patient Anatomy

    Energy Technology Data Exchange (ETDEWEB)

    Defoor, D; Stathakis, S; Mavroidis, P; Papanikolaou, N [University of Texas Health Science Center, UTHSCSA, San Antonio, TX (United States); Vazquez Quino, L [Midsouth Radation Physics, Little Rock, AR (United States)

    2014-06-01

    Purpose: This research, investigates the viability of using the Electronic portal imaging device (EPID) coupled with the treatment planning system (TPS), to calculate the doses delivered and verify agreement with the treatment plan. The results of QA analysis using the EPID, Delta4 and fluence calculations using the multi-leaf collimator (MLC) dynalog files on 10 IMRT patients are presented in this study. Methods: EPID Fluence Images in integrated mode and Dynalog files for each field were acquired for 10 IMRT (6MV) patients and processed through an in house MatLab program to create an opening density matrix (ODM) which was used as the input fluence for dose calculation with the TPS (Pinnacle3, Philips). The EPID used in this study was the aSi1000 Varian on a Novalis TX linac equipped with high definition MLC. The resulting dose distributions were then exported to VeriSoft (PTW) where a 3D gamma was calculated using 3mm-3% criteria. The Scandidos Delta4 phantom was also used to measure a 2D dose distribution for all 10 patients and a 2D gamma was calculated for each patient using the Delta4 software. Results: The average 3D gamma for all 10 patients using the EPID images was 98.2% ± 2.6%. The average 3D gamma using the dynalog files was 94.6% ± 4.9%. The average 2D gamma from the Delta4 was 98.1% ± 2.5%. The minimum 3D gamma for the EPID and dynalog reconstructed dose distributions was found on the same patient which had a very large PTV, requiring the jaws to open to the maximum field size. Conclusion: Use of the EPID, combined with a TPS is a viable method for QA of IMRT plans. A larger ODM size can be implemented to accommodate larger field sizes. An adaptation of this process to Volumetric Arc Therapy (VMAT) is currently under way.

  19. Product of Likelihood Ratio Scores Fusion of Dynamic Face, Text Independent Speech and On-line Signature Based Biometrics Verification Application Systems

    Directory of Open Access Journals (Sweden)

    Mohamed SOLTANE

    2015-09-01

    Full Text Available In this paper, the use of finite Gaussian mixture modal (GMM tuned using Expectation Maximization (EM estimating algorithms for score level data fusion is proposed. Automated biometric systems for human identification measure a “signature” of the human body, compare the resulting characteristic to a database, and render an application dependent decision. These biometric systems for personal authentication and identification are based upon physiological or behavioral features which are typically distinctive, Multi-biometric systems, which consolidate information from multiple biometric sources, are gaining popularity because they are able to overcome limitations such as non-universality, noisy sensor data, large intra-user variations and susceptibility to spoof attacks that are commonly encountered in mono modal biometric systems. Simulation result show that finite mixture modal (GMM is quite effective in modelling the genuine and impostor score densities, fusion based the product of Likelihood Ratio achieves a significant performance on eNTERFACE 2005 multi-biometric database based on dynamic face, on-line signature and text independent speech modalities.

  20. Epid cine acquisition mode for in vivo dosimetry in dynamic arc radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Fidanzio, Andrea [U.O. di Fisica Sanitaria Policlinico A. Gemelli, Universita Cattolica S. Cuore, Rome (Italy)], E-mail: andrea.fidanzio@rm.unicatt.it; Mameli, Alessandra; Placidi, Elisa; Greco, Francesca [U.O. di Fisica Sanitaria Policlinico A. Gemelli, Universita Cattolica S. Cuore, Rome (Italy); Stimato, Gerardina; Gaudino, Diego; Ramella, Sara; D' Angelillo, Rolando; Cellini, Francesco; Trodella, Lucio [U.O. di Radioterapia, Universita Campus Bio-Medico, Rome (Italy); Cilla, Savino; Grimaldi, Luca; D' Onofrio, Guido [U.O. di Fisica Sanitaria, Centro di Ricerca e Formazione ad Alta Tecnologia nelle Scienze Biomediche dell' Universita Cattolica S. Cuore, Campobasso (Italy); Azario, Luigi; Piermattei, Angelo [Istituto di Fisica, Universita Cattolica del S. Cuore, Rome (Italy)

    2008-02-15

    In this paper the cine acquisition mode of an electronic portal imaging device (EPID) has been calibrated and tested to determine the in vivo dose for dynamic conformal arc radiation therapy (DCAT). The EPID cine acquisition mode, that allows a frame acquisition rate of one image every 1.66 s, was studied with a monitor unit rate equal to 100 UM/min. In these conditions good signal stability, {+-}1% (2SD) evaluated during three months, signal reproducibility within {+-}0.8% (2SD) and linearity with dose and dose rate within {+-}1% (2SD) were obtained. The transit signal, S{sub t}, (due to the transmitted beam below the phantom) measured by the EPID cine acquisition mode was used to determine, (i) a set of correlation functions, F(w,L), defined as the ratio between S{sub t} and the dose at half thickness, D{sub m}, measured in solid water phantoms of different thicknesses, w and with square fields of side L, (ii) a set of factors, f(d,L), that take into account the different X-ray scatter contribution from the phantom to the S{sub t} signal as a function of the variation, d, of the air gap between the phantom and the EPID. The reconstruction of the isocenter dose, D{sub iso}, for DCAT was obtained convolving the transit signal values, obtained at different gantry angles, with the respective reconstruction factors determined by a house-made software. The method was tested with cylindrical and anthropomorphic phantoms and the results show that the reconstructed D{sub iso} values can be obtained with an accuracy within {+-}2.5% in cylindrical phantom and within {+-}3.4% for anthropomorphic phantom. In conclusion, the transit dosimetry by EPID was assessed to be adequate to perform DCAT in vivo dosimetry, that is not realizable with the other traditional techniques. Moreover, the method proposed here could be implemented to supply in vivo dose values in real time.

  1. A model-based 3D patient-specific pre-treatment QA method for VMAT using the EPID

    Science.gov (United States)

    McCowan, P. M.; Asuni, G.; van Beek, T.; van Uytven, E.; Kujanpaa, K.; McCurdy, B. M. C.

    2017-02-01

    This study reports the development and validation of a model-based, 3D patient dose reconstruction method for pre-treatment quality assurance using EPID images. The method is also investigated for sensitivity to potential MLC delivery errors. Each cine-mode EPID image acquired during plan delivery was processed using a previously developed back-projection dose reconstruction model providing a 3D dose estimate on the CT simulation data. Validation was carried out using 24 SBRT-VMAT patient plans by comparing: (1) ion chamber point dose measurements in a solid water phantom, (2) the treatment planning system (TPS) predicted 3D dose to the EPID reconstructed 3D dose in a solid water phantom, and (3) the TPS predicted 3D dose to the EPID and our forward predicted reconstructed 3D dose in the patient (CT data). AAA and AcurosXB were used for TPS predictions. Dose distributions were compared using 3%/3 mm (95% tolerance) and 2%/2 mm (90% tolerance) γ-tests in the planning target volume (PTV) and 20% dose volumes. The average percentage point dose differences between the ion chamber and the EPID, AcurosXB, and AAA were 0.73  ±  1.25%, 0.38  ±  0.96% and 1.06  ±  1.34% respectively. For the patient (CT) dose comparisons, seven (3%/3 mm) and nine (2%/2 mm) plans failed the EPID versus AAA. All plans passed the EPID versus Acuros XB and the EPID versus forward model γ-comparisons. Four types of MLC sensitive errors (opening, shifting, stuck, and retracting), of varying magnitude (0.2, 0.5, 1.0, 2.0 mm), were introduced into six different SBRT-VMAT plans. γ-comparisons of the erroneous EPID dose and original predicted dose were carried out using the same criteria as above. For all plans, the sensitivity testing using a 3%/3 mm γ-test in the PTV successfully determined MLC errors on the order of 1.0 mm, except for the single leaf retraction-type error. A 2%/2 mm criteria produced similar results with two more additional detected

  2. Preliminary studies for implementation of a MCL quality control using EPID (Portal Dosimetry); Estudos preliminares para implementacao de um controle de qualidade de MLC com o uso do EPID (Portal Dosimetry)

    Energy Technology Data Exchange (ETDEWEB)

    Mattos, Fabio R.; Furnari, Laura [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina

    2016-07-01

    A Quality Control (CQ) to ensure the expected performance of a Multileaf Collimator System (MLC) is essential for delivering dose in a safety and appropriate way. The time required for equipment control and dosimetry may be lowered when the Electronic Portal Image Device (EPID) is used. The aim of this paper was to check the resolution limits of the detection system for IMRT mode, and to do the analysis of three tests of MLC performance: Picket Fence, Slinding GAP, MLC versus Gantry. A Varian iX Clinac equipped with an 80 leaf Millennium MLC and with amorphous silicon based EPID (aS1000) was use. The EPID proved Effective, where errors up to 0,5 mm can be detected. Information about interleaf transmissions, dose profile and gravity influence in the leaf banks also were included. (author)

  3. Geometric control of the collimators with an image analysis program obtained by the EPID; Control geometrico del multilaminas con un programa de analisis de imagen obtenida con el EPID

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Enriquez, F.; Montejo Arteche, A.; Sanchez Mazon, J.; Vazquez Rodriguez, J. A.; Mendigueren Santiago, M. A.; Pacheco Baldor, M. T.; Raba Diez, J. I.

    2013-07-01

    To improve the traditional method of geometric adjustment of blades was a plugin from the Image J program that analyzes an image, acquired with the EPID accelerator, the way Stripe Test (test lines). The program was designed for an Elekta Accelerator model Precise, with slices of 1cm thick and a program of acquisition of images of the EPID Iview GT 3.4. At the end of the process it has resulted in the displacement, in millimeters, that needs to be done to adjust each of the blades. (Author)

  4. Estudio morfométrico de los epidídimos durante el desarrollo postnatal de corderos Barbados Blackbelly

    OpenAIRE

    Anahy Danae Vargas-Velázquez; Héctor Jiménez-Severiano

    2016-01-01

    Para caracterizar el desarrollo de los epidídimos, se castraron corderos Blackbelly al nacimiento y cada tres semanas hasta la 21 (n=4 a 6 por grupo). Se registró el peso de los epidídimos y de las tres regiones anatómicas y se tomaron muestras para morfometría. Se calculó el porcentaje de tejido tubular, el diámetro tubular, el grosor y área de la capa muscular, la altura y área del epitelio, y el diámetro y área de la luz tubular. El mayor crecimiento del epidídimo se observó entre las sema...

  5. Pre-treatment radiotherapy dose verification using Monte Carlo doselet modulation in a spherical phantom

    CERN Document Server

    Townson, Reid W

    2013-01-01

    Due to the increasing complexity of radiotherapy delivery, accurate dose verification has become an essential part of the clinical treatment process. The purpose of this work was to develop an electronic portal image (EPI) based pre-treatment verification technique capable of quickly reconstructing 3D dose distributions from both coplanar and non-coplanar treatments. The dose reconstruction is performed in a spherical water phantom by modulating, based on EPID measurements, pre-calculated Monte Carlo (MC) doselets defined on a spherical coordinate system. This is called the spherical doselet modulation (SDM) method. This technique essentially eliminates the statistical uncertainty of the MC dose calculations by exploiting both azimuthal symmetry in a patient-independent phase-space and symmetry of a virtual spherical water phantom. The symmetry also allows the number of doselets necessary for dose reconstruction to be reduced by a factor of about 250. In this work, 51 doselets were used. The SDM method mitiga...

  6. SU-E-T-781: Using An Electronic Portal Imaging Device (EPID) for Correlating Linac Photon Beam Energies

    Energy Technology Data Exchange (ETDEWEB)

    Yaddanapudi, S; Cai, B; Sun, B; Noel, C; Goddu, S; Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States)

    2015-06-15

    Purpose: Electronic portal imaging devices (EPIDs) have proven to be useful for measuring several parameters of interest in linear accelerator (linac) quality assurance (QA). The purpose of this project was to evaluate the feasibility of using EPIDs for determining linac photon beam energies. Methods: Two non-clinical Varian TrueBeam linacs (Varian Medical Systems, Palo Alto, CA) with 6MV and 10MV photon beams were used to perform the measurements. The linacs were equipped with an amorphous silicon based EPIDs (aSi1000) that were used for the measurements. We compared the use of flatness versus percent depth dose (PDD) for predicting changes in linac photon beam energy. PDD was measured in 1D water tank (Sun Nuclear Corporation, Melbourne FL) and the profiles were measured using 2D ion-chamber array (IC-Profiler, Sun Nuclear) and the EPID. Energy changes were accomplished by varying the bending magnet current (BMC). The evaluated energies conformed with the AAPM TG142 tolerance of ±1% change in PDD. Results: BMC changes correlating with a ±1% change in PDD corresponded with a change in flatness of ∼1% to 2% from baseline values on the EPID. IC Profiler flatness values had the same correlation. We observed a similar trend for the 10MV beam energy changes. Our measurements indicated a strong correlation between changes in linac photon beam energy and changes in flatness. For all machines and energies, beam energy changes produced change in the uniformity (AAPM TG-142), varying from ∼1% to 2.5%. Conclusions: EPID image analysis of beam profiles can be used to determine linac photon beam energy changes. Flatness-based metrics or uniformity as defined by AAPM TG-142 were found to be more sensitive to linac photon beam energy changes than PDD. Research funding provided by Varian Medical Systems. Dr. Sasa Mutic receives compensation for providing patient safety training services from Varian Medical Systems, the sponsor of this study.

  7. SU-D-201-06: Remote Dosmetric Auditing of VMAT Deliveries for Clinical Trials Using EPID

    Energy Technology Data Exchange (ETDEWEB)

    Legge, K; Miri, N [University of Newcastle (Australia); Lehmann, J [Calvary Mater Newcastle (Australia); Vial, P [Liverpool Hospital (Australia); Greer, P [University of Newcastle (Australia); Calvary Mater Newcastle (Australia)

    2016-06-15

    Purpose: To develop a method for remote dosimetric auditing the delivery of VMAT using EPID which allows for simple, inexpensive and time efficient dosimetric credentialing for clinical trials. Methods: Remote centers are provided with CT datasets and planning guidelines to produce VMAT plans for a head and neck and a post-prostatectomy treatment. Plans are transferred in the planning system to two virtual water equivalent phantoms, one flat and one cylindrical. Cine images are acquired during VMAT delivery to the EPID in air with gantry angle recorded in image headers. Centers also deliver provided calibration plans to enable EPID signal to dose conversion, determination of the central axis, and correction of EPID sag prior to analysis. EPID images and planned doses are sent to the central site. EPID cine images are converted to dose in the virtual phantoms using an established backprojection method (King et al., Med.Phys. 2012) with EPID backscatter correction. Individual arcs (with gantry angles collapsed to zero) are evaluated at 10 cm depth in the flat phantom using 2D gamma, and total doses are evaluated in the cylindrical phantom using 3D gamma. Results are reported for criteria of 3%,3mm, 3%,2mm and 2%,2mm for all points greater than 10% of global maximum. Results: The pilot study for Varian centers has commenced, and three centers have been audited for head and neck plans and two for post-prostatectomy plans to date. The mean pass rate for arc-by-arc 2D analysis at 3%,3mm is 99.5% and for 3D analysis is 95.8%. A method for Elekta linacs using an inclinometer for gantry angle information is under development. Conclusion: Preliminary results for this new method are promising. The method takes advantage of EPID equipment available at most centers and clinically established software to provide a feasible, low cost solution to credentialing centers for clinical trials. Funding has been provided from Calvary Mater Newcastle Department of Radiation Oncology, TROG

  8. Evaluation of dosimetric characteristics of multi-leaf and conventional collimated radiation fields using a scanning liquid ionization chamber EPID.

    Science.gov (United States)

    Mohammadi, M; Bezak, E

    2008-12-01

    The characteristics of radiation fields set up using conventional and Multi-Leaf collimators were investigated using a Scanning Liquid Ionization Chamber Electronic Portal Imaging Device (SLIC-EPID). Results showed that the radiation fields set up using MLCs are generally larger than those set up using conventional collimators. A significant difference was observed between the penumbra width for conventional and MLC radiation fields. SLIC-EPID was found to be a sensitive device to evaluate the characteristics of the radiation fields generated with MLCs.

  9. SU-E-T-265: Development of Dose-To-Water Conversion Models for Pre-Treatment Verification with the New AS1200 Imager

    Energy Technology Data Exchange (ETDEWEB)

    Miri, N [University of Newcastle, Newcastle, NSW (Australia); Baltes, C; Keller, P [Varian Medical Systems Imaging, Baden-Dättwil (Switzerland); Greer, P [Newcastle Mater Hospital, Newcastle, NSW (Australia)

    2015-06-15

    Purpose: To develop and evaluate models for dose verification of flattened (FF) and flattening filter free (FFF) beams for the new Varian aS1200 backscatter-shielded electronic portal imaging device (EPID). Methods: The model converts EPID images to incident energy fluence using deconvolution of EPID scatter kernels and fluence to dose in water using convolution with dose-to-water kernels. Model parameters were optimized using non-transmission EPID images of varying jaw defined field sizes for energies of 6 and 10 MV FF and FFF beams. Energy fluence was obtained from the Acuros planning system and reference dose profiles and output factors were measured at depths of 5, 10, 15 and 20 cm in a water phantom. Images for 34 IMRT fields acquired at 6 and 10 MV FF energy were converted to dose at 10 cm depth in water and compared to treatment planning system dose plane calculations using gamma criteria. Results: Gamma evaluations for the IMRT fields had mean (1 standard deviation) pass rates of 99.4% (0.8%) and mean gamma scores of 0.32 (0.06) with 2%, 2 mm criteria and 10% of maximum dose threshold. Conclusion: The developed model has been shown to be highly accurate for pre-treatment verification with the new aS1200 imager which does not display support-arm backscatter artefact and has improved dosimetric properties. Further investigation of FFF modes is in progress. The model is currently being evaluated at sites for potential clinical release.

  10. Comparison Between the Spectrum reconstruction methodology and release transmitted by both based in pictures taken EPID; Comparacion entre la metodologia de recostruccion de espectros por transmision y por disperison, ambas basadas en imagenes tomadas con EPID

    Energy Technology Data Exchange (ETDEWEB)

    Juste, B.; Miro, R.; Jambrina, A.; Campayo, J. M.; Diez, S.; Santos, A.; Verdu, V.

    2013-07-01

    A comparison of the spectral reconstruction based on data transmission and spectral reconstruction based on scattering data is presented, we have both developed using EPID images. It is shown that the reconstruction results based on transmission offer much better fit with the theoretical predictions.

  11. Verification Tools Secure Online Shopping, Banking

    Science.gov (United States)

    2010-01-01

    Just like rover or rocket technology sent into space, the software that controls these technologies must be extensively tested to ensure reliability and effectiveness. Ames Research Center invented the open-source Java Pathfinder (JPF) toolset for the deep testing of Java-based programs. Fujitsu Labs of America Inc., based in Sunnyvale, California, improved the capabilities of the JPF Symbolic Pathfinder tool, establishing the tool as a means of thoroughly testing the functionality and security of Web-based Java applications such as those used for Internet shopping and banking.

  12. Pre-treatment verification of RapidArc® using Electronic Portal Imaging Device; Verificacao pre-tratamento de RapidArc® utilizando Dispositivo Eletronico de Imagem Porta

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Marilia B.; Ferreira, Anne Caroline M.; Bittencourt, Guilherme R.; Pirani, Luis F.; Silveira, Thiago B., E-mail: mbeckerlima@gmail.com [Instituto Nacional do Cancer (INCA), Rio de Janeiro, RJ (Brazil)

    2012-12-15

    The RapidArc® is a novel but widespread technique to achieve intensity modulated beams. One of the major challenges concerning this technique is the pretreatment verification process. The aim of this paper was to analyze the viability of the Electronic Portal Imaging Device (EPID) used to perform the verification of RapidArc® using the Sun Nuclear SNC Patient software enable to EPID dose conversion (EPIDose license) and compare its results with punctual dose measurements against a low volume ion chamber. There were analyze five RapidArc® planning, evaluating, separately, planar and punctual doses for each arc. For punctual measurements was used a 0,15 cm³ volume ion chamber and the planar distributions, in Calibration Units (CU), were acquired using the EPID and then converted to absolute dose in centigray through EPIDose. The predicted doses were calculated using the AAA algorithm in Eclipse treatment planning system, version 8.6. The planar comparisons, performed in SNC Patient, employed the Gamma Index tool with a 4% dose difference, 4 mm distance to agreement and 20% threshold. The evaluation of punctual dose was defined by calculating deviations between predicted and measured doses. The mean approval percentage in planar distributions was 94.8% and the average deviation in punctual dose was -1.2%. The use of EPID for RapidArc® pre-treatment verification proved to be feasible and showed good sensibility, because of its high spatial resolution. However one must consider the uncertainty of the method. (author)

  13. Improvement of Varian a-Si EPID dosimetry measurements using a lead-shielded support-arm.

    Science.gov (United States)

    Rowshanfarzad, Pejman; Sabet, Mahsheed; O'Connor, Daryl J; Greer, Peter B

    2012-01-01

    Dosimetry measurements with Varian amorphous silicon electronic portal imaging devices (a-Si EPIDs) are affected by the backscattered radiation from the EPID support arm. In this study, the nonuniform backscatter from an E-type support arm was reduced by fixing a thick (12.2 × 10.5 × 0.5 cm(3)) piece of lead on top of the arm, and the remaining backscatter was modeled and included in an existing dose prediction algorithm. The applied backscatter kernel was the average of kernels on different regions of the EPID over the arm. The lead-shielded arm reduced the nonuniform backscatter component by about 50% for field sizes ranging from 3 × 3 to 30 × 30 cm(2) and the field symmetry improved for medium to large fields up to 3%. Gamma evaluation of the measured and modeled doses (2%, 2-mm criteria) showed that using the lead-shielded arm in the model increased the number of points with Gamma index <1 by 5.7% and decreased the mean Gamma by 0.201. Even using the lead alone (no modeling) could increase the number of points with Gamma index <1 by 4.7% and decrease the mean Gamma by 0.153. This is a simple and easy method to decrease the nonuniform arm backscatter and improve the accuracy of dosimetry measurements with the existing EPIDs used for clinical applications.

  14. Probabilistic Model for Dynamic Signature Verification System

    Directory of Open Access Journals (Sweden)

    Chai Tong Yuen

    2011-11-01

    Full Text Available This study has proposed the algorithm for signature verification system using dynamic parameters of the signature: pen pressure, velocity and position. The system is proposed to read, analyze and verify the signatures from the SUSig online database. Firstly, the testing and reference samples will have to be normalized, re-sampled and smoothed through pre-processing stage. In verification stage, the difference between reference and testing signatures will be calculated based on the proposed thresholded standard deviation method. A probabilistic acceptance model has been designed to enhance the performance of the verification system. The proposed algorithm has reported False Rejection Rate (FRR of 14.8% and False Acceptance Rate (FAR of 2.64%. Meanwhile, the classification rate of the system is around 97%.

  15. Verification Games: Crowd-Sourced Formal Verification

    Science.gov (United States)

    2016-03-01

    Government drawings, specifications, or other data included in this document for any purpose other than Government procurement does not in any way...information exchange, and its publication does not constitute the Government’s approval or disapproval of its ideas or findings. REPORT DOCUMENTATION ...DATES COVERED (From - To) JUN 2012 – SEP 2015 4. TITLE AND SUBTITLE VERIFICATION GAMES: CROWD-SOURCED FORMAL VERIFICATION 5a. CONTRACT NUMBER FA8750

  16. MO-D-213-08: Remote Dosimetric Credentialing for Clinical Trials with the Virtual EPID Standard Phantom Audit (VESPA)

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, J [Calvary Mater Newcastle, Newcastle, NSW (Australia); University of Sydney, Sydney, NSW (Australia); Miri, N [University of Newcastle, Newcastle, NSW (Australia); Vial, P [Liverpool Hospital, Liverpool, NSW (Australia); Hatton, J [Trans Tasman Radiation Oncology Group (TROG), Newcastle, NSW (Australia); Zwan, B; Sloan, K [Gosford Hospital, Gosford, NSW (Australia); Craig, A; Beenstock, V [Canterbury Regional Cancer and Haematology Service, Christchurch (New Zealand); Molloy, T [Orange Hospital, Orange, NSW (Australia); Greer, P [Calvary Mater Newcastle, Newcastle, NSW (Australia); University of Newcastle, Newcastle, NSW (Australia)

    2015-06-15

    Purpose: Report on implementation of a Virtual EPID Standard Phantom Audit (VESPA) for IMRT to support credentialing of facilities for clinical trials. Data is acquired by local facility staff and transferred electronically. Analysis is performed centrally. Methods: VESPA is based on published methods and a clinically established IMRT QA procedure, here extended to multi-vendor equipment. Facilities, provided with web-based comprehensive instructions and CT datasets, create IMRT treatment plans. They deliver the treatments directly to their EPID without phantom or couch in the beam. They also deliver a set of simple calibration fields. Collected EPID images are uploaded electronically. In the analysis, the dose is projected back into a virtual phantom and 3D gamma analysis is performed. 2D dose planes and linear dose profiles can be analysed when needed for clarification. Results: Pilot facilities covering a range of planning and delivery systems have performed data acquisition and upload successfully. Analysis showed agreement comparable to local experience with the method. Advantages of VESPA are (1) fast turnaround mainly driven by the facility’s capability to provide the requested EPID images, (2) the possibility for facilities performing the audit in parallel, as there is no need to wait for a phantom, (3) simple and efficient credentialing for international facilities, (4) a large set of data points, and (5) a reduced impact on resources and environment as there is no need to transport heavy phantoms or audit staff. Limitations of the current implementation of VESPA for trials credentialing are that it does not provide absolute dosimetry, therefore a Level 1 audit still required, and that it relies on correctly delivered open calibration fields, which are used for system calibration. Conclusion: The implemented EPID based IMRT audit system promises to dramatically improve credentialing efficiency for clinical trials and wider applications. VESPA for VMAT

  17. The impact of cine EPID image acquisition frame rate on markerless soft-tissue tracking

    Energy Technology Data Exchange (ETDEWEB)

    Yip, Stephen, E-mail: syip@lroc.harvard.edu; Rottmann, Joerg; Berbeco, Ross [Department of Radiation Oncology, Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2014-06-15

    Purpose: Although reduction of the cine electronic portal imaging device (EPID) acquisition frame rate through multiple frame averaging may reduce hardware memory burden and decrease image noise, it can hinder the continuity of soft-tissue motion leading to poor autotracking results. The impact of motion blurring and image noise on the tracking performance was investigated. Methods: Phantom and patient images were acquired at a frame rate of 12.87 Hz with an amorphous silicon portal imager (AS1000, Varian Medical Systems, Palo Alto, CA). The maximum frame rate of 12.87 Hz is imposed by the EPID. Low frame rate images were obtained by continuous frame averaging. A previously validated tracking algorithm was employed for autotracking. The difference between the programmed and autotracked positions of a Las Vegas phantom moving in the superior-inferior direction defined the tracking error (δ). Motion blurring was assessed by measuring the area change of the circle with the greatest depth. Additionally, lung tumors on 1747 frames acquired at 11 field angles from four radiotherapy patients are manually and automatically tracked with varying frame averaging. δ was defined by the position difference of the two tracking methods. Image noise was defined as the standard deviation of the background intensity. Motion blurring and image noise are correlated with δ using Pearson correlation coefficient (R). Results: For both phantom and patient studies, the autotracking errors increased at frame rates lower than 4.29 Hz. Above 4.29 Hz, changes in errors were negligible withδ < 1.60 mm. Motion blurring and image noise were observed to increase and decrease with frame averaging, respectively. Motion blurring and tracking errors were significantly correlated for the phantom (R = 0.94) and patient studies (R = 0.72). Moderate to poor correlation was found between image noise and tracking error with R −0.58 and −0.19 for both studies, respectively. Conclusions: Cine EPID

  18. Sci—Sat AM: Stereo — 01: 3D Pre-treatment Dose Verification for Stereotactic Body Radiation Therapy Patients

    Energy Technology Data Exchange (ETDEWEB)

    Asuni, G; Beek, T van; Van Utyven, E [Medical Physics Department, CancerCare Manitoba, Winnipeg, Manitoba (Canada); McCowan, P [Medical Physics Department, CancerCare Manitoba, Winnipeg, Manitoba (Canada); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba (Canada); McCurdy, B.M.C. [Medical Physics Department, CancerCare Manitoba, Winnipeg, Manitoba (Canada); Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba (Canada); Department of Radiology, University of Manitoba, Winnipeg Manitoba (Canada)

    2014-08-15

    Radical treatment techniques such as stereotactic body radiation therapy (SBRT) are becoming popular and they involve delivery of large doses in fewer fractions. Due to this feature of SBRT, a high-resolution, pre-treatment dose verification method that makes use of a 3D patient representation would be appropriate. Such a technique will provide additional information about dose delivered to the target volume(s) and organs-at-risk (OARs) in the patient volume compared to 2D verification methods. In this work, we investigate an electronic portal imaging device (EPID) based pre-treatment QA method which provides an accurate reconstruction of the 3D-dose distribution in the patient model. Customized patient plans are delivered ‘in air’ and the portal images are collected using the EPID in cine mode. The images are then analysed to determine an estimate of the incident energy fluence. This is then passed to a collapsed-cone convolution dose algorithm which reconstructs a 3D patient dose estimate on the CT imaging dataset. To date, the method has been applied to 5 SBRT patient plans. Reconstructed doses were compared to those calculated by the TPS. Reconstructed mean doses were mostly within 3% of those in the TPS. DVHs of target volumes and OARs compared well. The Chi pass rates using 3%/3mm in the high dose region are greater than 97% in all cases. These initial results demonstrate clinical feasibility and utility of a robust, efficient, effective and convenient pre-treatment QA method using EPID. Research sponsored in part by Varian Medical Systems.

  19. Imaging of moving fiducial markers during radiotherapy using a fast, efficient active pixel sensor based EPID

    Energy Technology Data Exchange (ETDEWEB)

    Osmond, John P. F.; Zin, Hafiz M.; Harris, Emma J.; Lupica, Giovanni; Allinson, Nigel M.; Evans, Philip M. [Joint Department of Physics, Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey, SM2 5PT (United Kingdom); Department of Electronic and Electrical Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD (United Kingdom); Lincoln School of Computer Science, University of Lincoln, Brayford Pool, Lincoln, LN6 7TS (United Kingdom); Joint Department of Physics, Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey, SM2 5PT (United Kingdom)

    2011-11-15

    Purpose: The purpose of this work was to investigate the use of an experimental complementary metal-oxide-semiconductor (CMOS) active pixel sensor (APS) for tracking of moving fiducial markers during radiotherapy. Methods: The APS has an active area of 5.4 x 5.4 cm and maximum full frame read-out rate of 20 frame s{sup -1}, with the option to read out a region-of-interest (ROI) at an increased rate. It was coupled to a 4 mm thick ZnWO4 scintillator which provided a quantum efficiency (QE) of 8% for a 6 MV x-ray treatment beam. The APS was compared with a standard iViewGT flat panel amorphous Silicon (a-Si) electronic portal imaging device (EPID), with a QE of 0.34% and a frame-rate of 2.5 frame s{sup -1}. To investigate the ability of the two systems to image markers, four gold cylinders of length 8 mm and diameter 0.8, 1.2, 1.6, and 2 mm were placed on a motion-platform. Images of the stationary markers were acquired using the APS at a frame-rate of 20 frame s{sup -1}, and a dose-rate of 143 MU min{sup -1} to avoid saturation. EPID images were acquired at the maximum frame-rate of 2.5 frame s{sup -1}, and a reduced dose-rate of 19 MU min{sup -1} to provide a similar dose per frame to the APS. Signal-to-noise ratio (SNR) of the background signal and contrast-to-noise ratio (CNR) of the marker signal relative to the background were evaluated for both imagers at doses of 0.125 to 2 MU. Results: Image quality and marker visibility was found to be greater in the APS with SNR {approx}5 times greater than in the EPID and CNR up to an order of magnitude greater for all four markers. To investigate the ability to image and track moving markers the motion-platform was moved to simulate a breathing cycle with period 6 s, amplitude 20 mm and maximum speed 13.2 mm s{sup -1}. At the minimum integration time of 50 ms a tracking algorithm applied to the APS data found all four markers with a success rate of {>=}92% and positional error {<=}90 {mu}m. At an integration time of 400

  20. Comparison of dose accuracy between 2D array detectors and Epid for IMRT of nasopharynx cancer

    Science.gov (United States)

    Altiparmak, Duygu; Coban, Yasin; Merih, Adil; Avci, Gulhan Guler; Yigitoglu, Ibrahim

    2017-02-01

    The aim of this study is to perform the dosimetric controls of nasopharynx cancer patient's intensity modulated radiation therapy (IMRT) treatment plans that generated by treatment planing system (TPS) with using two different equipments and also to make comparison in terms of their reliability and practicability. This study has been performed at Radiation Oncology Department, Medicine Faculty in Gaziosmanpasa University by using the VARIAN CLINAC DHX linear accelerator which is operated in the range of 6 MV. Selected 10 nasopharynx patients planned in TPS (Eclipce V13.0) and approved for treatment by medical physicists and radiation oncologists. These plans recalculated on EPID and mapcheck which are 2D dosimetric equipments to obtain dose maps. To compare these two dosimetric equipments gamma analysis method has been preferred. Achieved data is presented and discussed.

  1. Brote nosocomial y comunitario de queratoconjuntivitis epidémica en Navarra

    Directory of Open Access Journals (Sweden)

    Salcedo Miqueleiz Asunción

    1997-01-01

    Full Text Available FUNDAMENTO: La queratoconjuntivitis epidémica (QCE es una infección aguda, generalmente bilateral, que se presenta de forma esporádica o en brotes a partir de una fuente de infección común, que puede ser una consulta de oftalmología o una piscina. La queratitis puede evolucionar hacia la formación de lesiones subepiteliales cornéales que pueden persistir durante varios meses. El objetivo de este trabaji fue la descripción de un brote de queratoconjuntivitis epidémica ocurrido en Navarra (España entre Abril y Agosto de 1996 que afectó al menos a 266 personas MÉTODOS: Descripción del brote, definición de caso clínico, investigación microbiológica, e investigación epidemiológica del brote mediante encuesta. RESULTADOS: En la investigación epidemiológica destaca la existencia de 2 consultas de oftalmología como mecanismo de transmisión de la enfermedad en 47 de los 116 pacientes investigados. La diseminación de la enfermedad en el entorno de los pacientes se pudo conocer en 119 casos, de éstos, 62 se consideraron casos secundarios. El diagnóstico etiológico del brote se realizó a los 11 días de iniciada la investigación microbiológica, aislándose adenovirus en muestras conjuntivales de 8 de los 19 pacientes investigados. CONCLUSIONES: Las medidas de prevención instauradas para el control del brote y la eficacia de las mismas se pone de manifiesto por la reducción paulatina de casos.

  2. Verification Account Management System (VAMS)

    Data.gov (United States)

    Social Security Administration — The Verification Account Management System (VAMS) is the centralized location for maintaining SSA's verification and data exchange accounts. VAMS account management...

  3. Verification of ceramic structures

    NARCIS (Netherlands)

    Behar-Lafenetre, S.; Cornillon, L.; Rancurel, M.; Graaf, D. de; Hartmann, P.; Coe, G.; Laine, B.

    2012-01-01

    In the framework of the "Mechanical Design and Verification Methodologies for Ceramic Structures" contract [1] awarded by ESA, Thales Alenia Space has investigated literature and practices in affiliated industries to propose a methodological guideline for verification of ceramic spacecraft and instr

  4. The verification of the usability of the online Indares.com system in collecting data on physical activity – pilot study [Ověření využitelnosti online systému Indares.com pro sběr dat o pohybové aktivitě – pilotní studie

    Directory of Open Access Journals (Sweden)

    Josef Mitáš

    2008-05-01

    Full Text Available In order to reduce the increase of obesity and an inactive healthy lifestyle in the population, we are seeking means which would enhance a change in physical activity behavior worldwide. Information technologies, especially the internet, are among these means. Research has shown internet intervention to be effective in enhancing health in the population. The aim of the pilot study is to verify the usability of the online Indares.com system in collecting data on physical activity (PA and at the same time to analyze a possible use of the system for intervention programs. The verification of the Indares.com system was carried out in the spring term (from January to May 2008 in a sample of 114 students at Valdosta State University who recorded their PA regularly into the system. The study analyzed the data from the first 12 weeks of the semester. The results show that the Indares.com system is an effective tool for the online collection of data on PA in its users and that the recorded data can be used for research purposes. Furthermore, the obtained information suggests that the Indares.com system can be used in internet intervention programs. [Ve snaze zmírnit trend nárůstu obezity a inaktivního způsobu života populace jsou celosvětově hledány prostředky, které by přispěly k žádoucí změně pohybového chování lidí. Mezi tyto prostředky patří moderní informační technologie, zejména internet. Dosavadní výzkumy spíše potvrzují efektivnost internetových intervencí zacílených na zdraví populace. Cílem této pilotní studie bylo ověřit praktickou využitelnost internetové aplikace Indares.com ke sběru dat o pohybové aktivitě (PA a současně analyzovat možnosti využití systému pro intervenční programy. Ověřování systému Indares.com bylo uskutečněno během jarního semestru (leden až květen 2008 na 114 studentech Valdosta State University, kteří svou PA pravidelně zapisovali do systému. V t

  5. Quality control program of multi-leaf collimation based EPID for teams with Rapidarc; Programa de control de calidad del sistema de colimacion Multilamina basado en EPID para equipos con Rapidarc

    Energy Technology Data Exchange (ETDEWEB)

    Pujades Claumarchirant, M. C.; Richart Sancho, J.; Gimeno Olmos, J.; Lliso Valverde, F.; Carmona Mesenguer, V.; Garcia Martinez, M. T.; Palomo Llinares, R.; Ballester Pallares, F.; Perez Calatayud, J.

    2013-07-01

    The objective of this work is to show a collection of different recommendations on the control of quality of collimation multi-leaf system and present the selection of tests based on the electronic imaging device (EPID) portal that have decided to establish in our Center, where in addition to the requirements of quality assurance generic for collimation multi-leaf system quality control methods have been included for RapidArc. (Author)

  6. 75 FR 34439 - Defense Science Board Task Force on Nuclear Treaty Monitoring and Verification

    Science.gov (United States)

    2010-06-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary Defense Science Board Task Force on Nuclear Treaty Monitoring and Verification... Science Board Task Force on Nuclear Treaty Monitoring and Verification will meet in closed session on...

  7. 75 FR 43943 - Defense Science Board; Task Force on Nuclear Treaty Monitoring and Verification

    Science.gov (United States)

    2010-07-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Office of the Secretary Defense Science Board; Task Force on Nuclear Treaty Monitoring and Verification... Science Board Task Force on Nuclear Treaty Monitoring and Verification will meet in closed...

  8. 76 FR 50129 - Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing...

    Science.gov (United States)

    2011-08-12

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 72 and 75 RIN 2060-AQ06 Protocol Gas Verification Program and Minimum Competency... Verification Program and Minimum Competency Requirements for Air Emission Testing final rule, which...

  9. Constituição epidêmica: velho e novo nas teorias e práticas da epidemiologia

    OpenAIRE

    2001-01-01

    O artigo analisa a importância da idéia de constituição epidêmica, identificada pela presença recorrente do pensamento hipocrático na história da epidemiologia. Em termos gerais, constituição relaciona epidemias a circunstâncias geográfico-atmosféricas. O que se destaca é a concepção do fenômeno epidêmico como desequilíbrio da harmonia da natureza, como totalidade e ultrapassando a dimensão geográfica. Permanência de um pensamento hipocrático não significa a existência de uma continuidade. A ...

  10. Estudio morfométrico de los epidídimos durante el desarrollo postnatal de corderos Barbados Blackbelly

    Directory of Open Access Journals (Sweden)

    Anahy Danae Vargas-Velázquez

    2016-01-01

    Full Text Available Para caracterizar el desarrollo de los epidídimos, se castraron corderos Blackbelly al nacimiento y cada tres semanas hasta la 21 (n=4 a 6 por grupo. Se registró el peso de los epidídimos y de las tres regiones anatómicas y se tomaron muestras para morfometría. Se calculó el porcentaje de tejido tubular, el diámetro tubular, el grosor y área de la capa muscular, la altura y área del epitelio, y el diámetro y área de la luz tubular. El mayor crecimiento del epidídimo se observó entre las semanas 9 y 18; la cola comenzó a desarrollarse antes que las otras regiones; el peso de ésta fue mayor entre el nacimiento y la semana 12, pero de la semana 15 a la 21 no difirió de la cabeza. En general, el diámetro tubular, el grosor y área de la capa muscular y el diámetro y área de la luz fueron mayores en la cola. La altura del epitelio fue mayor en la cola hasta la semana 9, pero la situación se invirtió a partir de la semana 12. De acuerdo a lo que se conoce de esta raza, la cola comenzó a desarrollarse antes de aparecer la luz de los túbulos seminíferos y del aumento de las concentraciones de testosterona, mientras que el desarrollo de la cabeza y el cuerpo coincidió con el aumento de la capacidad esteroidogénica y la secreción del fluido tubular. Tales hallazgos sugieren diferentes requerimientos de estimulación endocrina y lumicrina para el desarrollo normal de las diferentes regiones del epidídimo.

  11. Advanced verification topics

    CERN Document Server

    Bhattacharya, Bishnupriya; Hall, Gary; Heaton, Nick; Kashai, Yaron; Khan Neyaz; Kirshenbaum, Zeev; Shneydor, Efrat

    2011-01-01

    The Accellera Universal Verification Methodology (UVM) standard is architected to scale, but verification is growing and in more than just the digital design dimension. It is growing in the SoC dimension to include low-power and mixed-signal and the system integration dimension to include multi-language support and acceleration. These items and others all contribute to the quality of the SOC so the Metric-Driven Verification (MDV) methodology is needed to unify it all into a coherent verification plan. This book is for verification engineers and managers familiar with the UVM and the benefits it brings to digital verification but who also need to tackle specialized tasks. It is also written for the SoC project manager that is tasked with building an efficient worldwide team. While the task continues to become more complex, Advanced Verification Topics describes methodologies outside of the Accellera UVM standard, but that build on it, to provide a way for SoC teams to stay productive and profitable.

  12. Monte Carlo-based adaptive EPID dose kernel accounting for different field size responses of imagers.

    Science.gov (United States)

    Wang, Song; Gardner, Joseph K; Gordon, John J; Li, Weidong; Clews, Luke; Greer, Peter B; Siebers, Jeffrey V

    2009-08-01

    The aim of this study is to present an efficient method to generate imager-specific Monte Carlo (MC)-based dose kernels for amorphous silicon-based electronic portal image device dose prediction and determine the effective backscattering thicknesses for such imagers. EPID field size-dependent responses were measured for five matched Varian accelerators from three institutions with 6 MV beams at the source to detector distance (SDD) of 105 cm. For two imagers, measurements were made with and without the imager mounted on the robotic supporting arm. Monoenergetic energy deposition kernels with 0-2.5 cm of water backscattering thicknesses were simultaneously computed by MC to a high precision. For each imager, the backscattering thickness required to match measured field size responses was determined. The monoenergetic kernel method was validated by comparing measured and predicted field size responses at 150 cm SDD, 10 x 10 cm2 multileaf collimator (MLC) sliding window fields created with 5, 10, 20, and 50 mm gaps, and a head-and-neck (H&N) intensity modulated radiation therapy (IMRT) patient field. Field size responses for the five different imagers deviated by up to 1.3%. When imagers were removed from the robotic arms, response deviations were reduced to 0.2%. All imager field size responses were captured by using between 1.0 and 1.6 cm backscatter. The predicted field size responses by the imager-specific kernels matched measurements for all involved imagers with the maximal deviation of 0.34%. The maximal deviation between the predicted and measured field size responses at 150 cm SDD is 0.39%. The maximal deviation between the predicted and measured MLC sliding window fields is 0.39%. For the patient field, gamma analysis yielded that 99.0% of the pixels have gamma < 1 by the 2%, 2 mm criteria with a 3% dose threshold. Tunable imager-specific kernels can be generated rapidly and accurately in a single MC simulation. The resultant kernels are imager position

  13. SSN Verification Service

    Data.gov (United States)

    Social Security Administration — The SSN Verification Service is used by Java applications to execute the GUVERF02 service using the WebSphere/CICS Interface. It accepts several input data fields...

  14. Integrated Java Bytecode Verification

    DEFF Research Database (Denmark)

    Gal, Andreas; Probst, Christian; Franz, Michael

    2005-01-01

    Existing Java verifiers perform an iterative data-flow analysis to discover the unambiguous type of values stored on the stack or in registers. Our novel verification algorithm uses abstract interpretation to obtain definition/use information for each register and stack location in the program......, which in turn is used to transform the program into Static Single Assignment form. In SSA, verification is reduced to simple type compatibility checking between the definition type of each SSA variable and the type of each of its uses. Inter-adjacent transitions of a value through stack and registers...... are no longer verified explicitly. This integrated approach is more efficient than traditional bytecode verification but still as safe as strict verification, as overall program correctness can be induced once the data flow from each definition to all associated uses is known to be type-safe....

  15. Voltage verification unit

    Science.gov (United States)

    Martin, Edward J.

    2008-01-15

    A voltage verification unit and method for determining the absence of potentially dangerous potentials within a power supply enclosure without Mode 2 work is disclosed. With this device and method, a qualified worker, following a relatively simple protocol that involves a function test (hot, cold, hot) of the voltage verification unit before Lock Out/Tag Out and, and once the Lock Out/Tag Out is completed, testing or "trying" by simply reading a display on the voltage verification unit can be accomplished without exposure of the operator to the interior of the voltage supply enclosure. According to a preferred embodiment, the voltage verification unit includes test leads to allow diagnostics with other meters, without the necessity of accessing potentially dangerous bus bars or the like.

  16. Feature-Aware Verification

    CERN Document Server

    Apel, Sven; Wendler, Philipp; von Rhein, Alexander; Beyer, Dirk

    2011-01-01

    A software product line is a set of software products that are distinguished in terms of features (i.e., end-user--visible units of behavior). Feature interactions ---situations in which the combination of features leads to emergent and possibly critical behavior--- are a major source of failures in software product lines. We explore how feature-aware verification can improve the automatic detection of feature interactions in software product lines. Feature-aware verification uses product-line verification techniques and supports the specification of feature properties along with the features in separate and composable units. It integrates the technique of variability encoding to verify a product line without generating and checking a possibly exponential number of feature combinations. We developed the tool suite SPLverifier for feature-aware verification, which is based on standard model-checking technology. We applied it to an e-mail system that incorporates domain knowledge of AT&T. We found that feat...

  17. Standard Verification System (SVS)

    Data.gov (United States)

    Social Security Administration — SVS is a mainframe program that accesses the NUMIDENT to perform SSN verifications. This program is called by SSA Internal applications to verify SSNs. There is also...

  18. Monitoring daily MLC positional errors using trajectory log files and EPID measurements for IMRT and VMAT deliveries

    Science.gov (United States)

    Agnew, A.; Agnew, C. E.; Grattan, M. W. D.; Hounsell, A. R.; McGarry, C. K.

    2014-05-01

    This work investigated the differences between multileaf collimator (MLC) positioning accuracy determined using either log files or electronic portal imaging devices (EPID) and then assessed the possibility of reducing patient specific quality control (QC) via phantom-less methodologies. In-house software was developed, and validated, to track MLC positional accuracy with the rotational and static gantry picket fence tests using an integrated electronic portal image. This software was used to monitor MLC daily performance over a 1 year period for two Varian TrueBeam linear accelerators, with the results directly compared with MLC positions determined using leaf trajectory log files. This software was validated by introducing known shifts and collimator errors. Skewness of the MLCs was found to be 0.03 ± 0.06° (mean ±1 standard deviation (SD)) and was dependent on whether the collimator was rotated manually or automatically. Trajectory log files, analysed using in-house software, showed average MLC positioning errors with a magnitude of 0.004 ± 0.003 mm (rotational) and 0.004 ± 0.011 mm (static) across two TrueBeam units over 1 year (mean ±1 SD). These ranges, as indicated by the SD, were lower than the related average MLC positioning errors of 0.000 ± 0.025 mm (rotational) and 0.000 ± 0.039 mm (static) that were obtained using the in-house EPID based software. The range of EPID measured MLC positional errors was larger due to the inherent uncertainties of the procedure. Over the duration of the study, multiple MLC positional errors were detected using the EPID based software but these same errors were not detected using the trajectory log files. This work shows the importance of increasing linac specific QC when phantom-less methodologies, such as the use of log files, are used to reduce patient specific QC. Tolerances of 0.25 mm have been created for the MLC positional errors using the EPID-based automated picket fence test. The software allows diagnosis

  19. aSi EPIDs for the in-vivo dosimetry of static and dynamic beams

    Energy Technology Data Exchange (ETDEWEB)

    Piermattei, A. [Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Roma Tre, 00146 Roma (Italy); Istituto di Fisica e U.O.C. di Fisica Sanitaria, Università Cattolica del S. Cuore, 00168 Roma (Italy); Cilla, S. [Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Roma Tre, 00146 Roma (Italy); U.O. di Fisica Sanitaria, Fondazione per la Ricerca e Cura ‘Giovanni Paolo II’, 86100 Campobasso (Italy); Azario, L.; Greco, F. [Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Roma Tre, 00146 Roma (Italy); Istituto di Fisica e U.O.C. di Fisica Sanitaria, Università Cattolica del S. Cuore, 00168 Roma (Italy); Russo, M. [Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Roma Tre, 00146 Roma (Italy); U.O. di Fisica Sanitaria, Ospedale Belcolle, 01100 Viterbo (Italy); Grusio, M. [Istituto di Fisica e U.O.C. di Fisica Sanitaria, Università Cattolica del S. Cuore, 00168 Roma (Italy); Orlandini, L. [U.O. di Fisica Medica, Centro Oncologico Fiorentino, 50121 Firenze (Italy); Fidanzio, A., E-mail: andrea.fidanzio@rm.unicatt.it [Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Roma Tre, 00146 Roma (Italy); Istituto di Fisica e U.O.C. di Fisica Sanitaria, Università Cattolica del S. Cuore, 00168 Roma (Italy)

    2015-10-01

    Portal imaging by amorphous silicon (aSi) photodiode is currently the most applied technology for in-vivo dosimetry (IVD) of static and dynamic radiotherapy beams. The strategy, adopted in this work to perform the IVD procedure by aSi EPID, is based on: in patient reconstruction of the isocenter dose and day to day comparison between 2D-portal images to verify the reproducibility of treatment delivery. About 20.000 tests have been carried out in this last 3 years in 8 radiotherapy centers using the SOFTDISO program. The IVD results show that: (i) the procedure can be implemented for linacs of different manufacturer, (ii) the IVD analysis can be obtained on a computer screen, in quasi real time (about 2 min after the treatment delivery) and (iii) once the causes of the discrepancies were eliminated, all the global IVD tests for single patient were within the acceptance criteria defined by: ±5% for the isocenter dose, and P{sub γ<1}≥90% of the checked points for the 2D portal image γ-analysis. This work is the result of a project supported by the Istituto Nazionale di Fisica Nucleare (INFN) and Università Cattolica del S.Cuore (UCSC)

  20. aSi EPIDs for the in-vivo dosimetry of static and dynamic beams

    Science.gov (United States)

    Piermattei, A.; Cilla, S.; Azario, L.; Greco, F.; Russo, M.; Grusio, M.; Orlandini, L.; Fidanzio, A.

    2015-10-01

    Portal imaging by amorphous silicon (aSi) photodiode is currently the most applied technology for in-vivo dosimetry (IVD) of static and dynamic radiotherapy beams. The strategy, adopted in this work to perform the IVD procedure by aSi EPID, is based on: in patient reconstruction of the isocenter dose and day to day comparison between 2D-portal images to verify the reproducibility of treatment delivery. About 20.000 tests have been carried out in this last 3 years in 8 radiotherapy centers using the SOFTDISO program. The IVD results show that: (i) the procedure can be implemented for linacs of different manufacturer, (ii) the IVD analysis can be obtained on a computer screen, in quasi real time (about 2 min after the treatment delivery) and (iii) once the causes of the discrepancies were eliminated, all the global IVD tests for single patient were within the acceptance criteria defined by: ±5% for the isocenter dose, and PγFisica Nucleare (INFN) and Università Cattolica del S.Cuore (UCSC).

  1. A comprehensive EPID-based 3D validation technique for TrueBeam-delivered VMAT plans

    Science.gov (United States)

    Ansbacher, W.; Gagne, I. M.; Swift, C.-L.

    2014-03-01

    Purpose: To develop and validate a pre-treatment EPI dosimetry method on Varian TrueBeam linacs using continuous imaging, with reconstruction in a 3D cylindrical phantom geometry. Methods: Delivery of VMAT plans with continuous imaging is currently possible only in Research Mode on TrueBeam linacs, with images acquired in a proprietary format. An earlier technique was adapted to take advantage of technical improvements in EPID delivery, and was tested under various acquisition conditions. The dosimetry of VMAT plans was evaluated at isocentre and within patient volumes that had been transferred to the virtual phantom. Results: Approximately 60 portal image projections per arc were found to be adequate for 3D reconstruction in phantom volumes of 28cm diameter. Twelve prostate, CNS and Head & Neck deliveries were evaluated in Research mode relative to the corresponding Eclipse (v.10) treatment plans, and to measurements on an ArcCheck device in Treatment mode. Mean dose differences at isocentre were within 2% for the three-way comparison, and in PTV volumes were within 1% (s.d. 1%). However, some discrepancies were observed in ArcCheck results that may be related to the small dimensions of certain VMAT apertures. Conclusions: EPI dosimetry with 3D dose reconstruction is an accurate, comprehensive and efficient pre-treatment validation technique for VMAT delivery. Although currently limited to a research mode on TrueBeam, it has the potential to be implemented for clinical use.

  2. Feasibility study of a dual detector configuration concept for simultaneous megavoltage imaging and dose verification in radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, Shrikant, E-mail: shrikant.Deshpande@sswahs.nsw.gov.au [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centre, Sydney NSW 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong NSW 2170 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); McNamara, Aimee L. [Ingham Institute for Applied Medical Research, Sydney, NSW 2170, Australia and Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Holloway, Lois [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centre, Sydney NSW 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong NSW 2170 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); South Western Sydney Clinical School, University of New South Wales, Sydney, NSW 2052 (Australia); Metcalfe, Peter [Centre for Medical Radiation Physics, University of Wollongong, Wollongong NSW 2170 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); Vial, Philip [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centre, Sydney NSW 2170 (Australia); Ingham Institute for Applied Medical Research, Sydney, NSW 2170 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)

    2015-04-15

    Purpose: To test the feasibility of a dual detector concept for comprehensive verification of external beam radiotherapy. Specifically, the authors test the hypothesis that a portal imaging device coupled to a 2D dosimeter provides a system capable of simultaneous imaging and dose verification, and that the presence of each device does not significantly detract from the performance of the other. Methods: The dual detector configuration comprised of a standard radiotherapy electronic portal imaging device (EPID) positioned directly on top of an ionization-chamber array (ICA) with 2 cm solid water buildup material (between EPID and ICA) and 5 cm solid backscatter material. The dose response characteristics of the ICA and the imaging performance of the EPID in the dual detector configuration were compared to the performance in their respective reference clinical configurations. The reference clinical configurations were 6 cm solid water buildup material, an ICA, and 5 cm solid water backscatter material as the reference dosimetry configuration, and an EPID with no additional buildup or solid backscatter material as the reference imaging configuration. The dose response of the ICA was evaluated by measuring the detector’s response with respect to off-axis position, field size, and transit object thickness. Clinical dosimetry performance was evaluated by measuring a range of clinical intensity-modulated radiation therapy (IMRT) beams in transit and nontransit geometries. The imaging performance of the EPID was evaluated quantitatively by measuring the contrast-to-noise ratio (CNR) and spatial resolution. Images of an anthropomorphic phantom were also used for qualitative assessment. Results: The measured off-axis and field size response with the ICA in both transit and nontransit geometries for both dual detector configuration and reference dosimetry configuration agreed to within 1%. Transit dose response as a function of object thickness agreed to within 0.5%. All

  3. Embedded software verification and debugging

    CERN Document Server

    Winterholer, Markus

    2017-01-01

    This book provides comprehensive coverage of verification and debugging techniques for embedded software, which is frequently used in safety critical applications (e.g., automotive), where failures are unacceptable. Since the verification of complex systems needs to encompass the verification of both hardware and embedded software modules, this book focuses on verification and debugging approaches for embedded software with hardware dependencies. Coverage includes the entire flow of design, verification and debugging of embedded software and all key approaches to debugging, dynamic, static, and hybrid verification. This book discusses the current, industrial embedded software verification flow, as well as emerging trends with focus on formal and hybrid verification and debugging approaches. Includes in a single source the entire flow of design, verification and debugging of embedded software; Addresses the main techniques that are currently being used in the industry for assuring the quality of embedded softw...

  4. Computerized method for estimation of the location of a lung tumor on EPID cine images without implanted markers in stereotactic body radiotherapy

    Science.gov (United States)

    Arimura, H.; Egashira, Y.; Shioyama, Y.; Nakamura, K.; Yoshidome, S.; Anai, S.; Nomoto, S.; Honda, H.; Toyofuku, F.; Higashida, Y.; Onizuka, Y.; Terashima, H.

    2009-02-01

    The purpose of this study was to develop a computerized method for estimation of the location of a lung tumor in cine images on an electronic portal imaging device (EPID) without implanted markers during stereotactic body radiotherapy (SBRT). Each tumor region was segmented in the first EPID cine image, i.e., reference portal image, based on a multiple-gray level thresholding technique and a region growing technique, and then the image including the tumor region was cropped as a 'tumor template' image. The tumor location was determined as the position in which the tumor template image took the maximum cross-correlation value within each consecutive portal image, which was acquired in cine mode on the EPID in treatment. EPID images with 512 × 384 pixels (pixel size: 0.56 mm) were acquired at a sampling rate of 0.5 frame s-1 by using energies of 4, 6 or 10 MV on linear accelerators. We applied our proposed method to EPID cine images (226 frames) of 12 clinical cases (ages: 51-83, mean: 72) with a non-small cell lung cancer. As a result, the average location error between tumor points obtained by our method and the manual method was 1.47 ± 0.60 mm. This preliminary study suggests that our method based on the tumor template matching technique might be feasible for tracking the location of a lung tumor without implanted markers in SBRT.

  5. Computerized method for estimation of the location of a lung tumor on EPID cine images without implanted markers in stereotactic body radiotherapy.

    Science.gov (United States)

    Arimura, H; Egashira, Y; Shioyama, Y; Nakamura, K; Yoshidome, S; Anai, S; Nomoto, S; Honda, H; Toyofuku, F; Higashida, Y; Onizuka, Y; Terashima, H

    2009-02-07

    The purpose of this study was to develop a computerized method for estimation of the location of a lung tumor in cine images on an electronic portal imaging device (EPID) without implanted markers during stereotactic body radiotherapy (SBRT). Each tumor region was segmented in the first EPID cine image, i.e., reference portal image, based on a multiple-gray level thresholding technique and a region growing technique, and then the image including the tumor region was cropped as a 'tumor template' image. The tumor location was determined as the position in which the tumor template image took the maximum cross-correlation value within each consecutive portal image, which was acquired in cine mode on the EPID in treatment. EPID images with 512 x 384 pixels (pixel size: 0.56 mm) were acquired at a sampling rate of 0.5 frame s(-1) by using energies of 4, 6 or 10 MV on linear accelerators. We applied our proposed method to EPID cine images (226 frames) of 12 clinical cases (ages: 51-83, mean: 72) with a non-small cell lung cancer. As a result, the average location error between tumor points obtained by our method and the manual method was 1.47 +/- 0.60 mm. This preliminary study suggests that our method based on the tumor template matching technique might be feasible for tracking the location of a lung tumor without implanted markers in SBRT.

  6. Computerized method for estimation of the location of a lung tumor on EPID cine images without implanted markers in stereotactic body radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Arimura, H; Toyofuku, F; Higashida, Y; Onizuka, Y; Terashima, H [Department of Health Sciences, Faculty of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Egashira, Y [Department of Health Sciences, School of Medicine, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Shioyama, Y; Nomoto, S; Honda, H [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Nakamura, K [Department of Radiology, Faculty of Medicine, Fukuoka University, 8-19-1, Nanakuma, Jyonan-ku, Fukuoka 814-0180 (Japan); Yoshidome, S; Anai, S [Division of Radiology, Department of Medical Technology, Kyushu University Hospital, Fukuoka 812-8582 (Japan)], E-mail: arimura@shs.kyushu-u.ac.jp

    2009-02-07

    The purpose of this study was to develop a computerized method for estimation of the location of a lung tumor in cine images on an electronic portal imaging device (EPID) without implanted markers during stereotactic body radiotherapy (SBRT). Each tumor region was segmented in the first EPID cine image, i.e., reference portal image, based on a multiple-gray level thresholding technique and a region growing technique, and then the image including the tumor region was cropped as a 'tumor template' image. The tumor location was determined as the position in which the tumor template image took the maximum cross-correlation value within each consecutive portal image, which was acquired in cine mode on the EPID in treatment. EPID images with 512 x 384 pixels (pixel size: 0.56 mm) were acquired at a sampling rate of 0.5 frame s{sup -1} by using energies of 4, 6 or 10 MV on linear accelerators. We applied our proposed method to EPID cine images (226 frames) of 12 clinical cases (ages: 51-83, mean: 72) with a non-small cell lung cancer. As a result, the average location error between tumor points obtained by our method and the manual method was 1.47 {+-} 0.60 mm. This preliminary study suggests that our method based on the tumor template matching technique might be feasible for tracking the location of a lung tumor without implanted markers in SBRT.

  7. Wind gust warning verification

    Science.gov (United States)

    Primo, Cristina

    2016-07-01

    Operational meteorological centres around the world increasingly include warnings as one of their regular forecast products. Warnings are issued to warn the public about extreme weather situations that might occur leading to damages and losses. In forecasting these extreme events, meteorological centres help their potential users in preventing the damage or losses they might suffer. However, verifying these warnings requires specific methods. This is due not only to the fact that they happen rarely, but also because a new temporal dimension is added when defining a warning, namely the time window of the forecasted event. This paper analyses the issues that might appear when dealing with warning verification. It also proposes some new verification approaches that can be applied to wind warnings. These new techniques are later applied to a real life example, the verification of wind gust warnings at the German Meteorological Centre ("Deutscher Wetterdienst"). Finally, the results obtained from the latter are discussed.

  8. Nuclear disarmament verification

    Energy Technology Data Exchange (ETDEWEB)

    DeVolpi, A.

    1993-12-31

    Arms control treaties, unilateral actions, and cooperative activities -- reflecting the defusing of East-West tensions -- are causing nuclear weapons to be disarmed and dismantled worldwide. In order to provide for future reductions and to build confidence in the permanency of this disarmament, verification procedures and technologies would play an important role. This paper outlines arms-control objectives, treaty organization, and actions that could be undertaken. For the purposes of this Workshop on Verification, nuclear disarmament has been divided into five topical subareas: Converting nuclear-weapons production complexes, Eliminating and monitoring nuclear-weapons delivery systems, Disabling and destroying nuclear warheads, Demilitarizing or non-military utilization of special nuclear materials, and Inhibiting nuclear arms in non-nuclear-weapons states. This paper concludes with an overview of potential methods for verification.

  9. College Student Web Use, Perceptions of Information Credibility, and Verification Behavior

    Science.gov (United States)

    Metzger, Miriam J.; Flanagin, Andrew J.; Zwarun, Lara

    2003-01-01

    Concerns about the potentially dubious nature of online information and users' ability to evaluate it appropriately prompted this research on college students' use of Web-based information, their perceptions of information credibility, and their online verification behaviors. Two studies were conducted to address these issues. Results of the first…

  10. Verification and validation benchmarks.

    Energy Technology Data Exchange (ETDEWEB)

    Oberkampf, William Louis; Trucano, Timothy Guy

    2007-02-01

    Verification and validation (V&V) are the primary means to assess the accuracy and reliability of computational simulations. V&V methods and procedures have fundamentally improved the credibility of simulations in several high-consequence fields, such as nuclear reactor safety, underground nuclear waste storage, and nuclear weapon safety. Although the terminology is not uniform across engineering disciplines, code verification deals with assessing the reliability of the software coding, and solution verification deals with assessing the numerical accuracy of the solution to a computational model. Validation addresses the physics modeling accuracy of a computational simulation by comparing the computational results with experimental data. Code verification benchmarks and validation benchmarks have been constructed for a number of years in every field of computational simulation. However, no comprehensive guidelines have been proposed for the construction and use of V&V benchmarks. For example, the field of nuclear reactor safety has not focused on code verification benchmarks, but it has placed great emphasis on developing validation benchmarks. Many of these validation benchmarks are closely related to the operations of actual reactors at near-safety-critical conditions, as opposed to being more fundamental-physics benchmarks. This paper presents recommendations for the effective design and use of code verification benchmarks based on manufactured solutions, classical analytical solutions, and highly accurate numerical solutions. In addition, this paper presents recommendations for the design and use of validation benchmarks, highlighting the careful design of building-block experiments, the estimation of experimental measurement uncertainty for both inputs and outputs to the code, validation metrics, and the role of model calibration in validation. It is argued that the understanding of predictive capability of a computational model is built on the level of

  11. Requirement Assurance: A Verification Process

    Science.gov (United States)

    Alexander, Michael G.

    2011-01-01

    Requirement Assurance is an act of requirement verification which assures the stakeholder or customer that a product requirement has produced its "as realized product" and has been verified with conclusive evidence. Product requirement verification answers the question, "did the product meet the stated specification, performance, or design documentation?". In order to ensure the system was built correctly, the practicing system engineer must verify each product requirement using verification methods of inspection, analysis, demonstration, or test. The products of these methods are the "verification artifacts" or "closure artifacts" which are the objective evidence needed to prove the product requirements meet the verification success criteria. Institutional direction is given to the System Engineer in NPR 7123.1A NASA Systems Engineering Processes and Requirements with regards to the requirement verification process. In response, the verification methodology offered in this report meets both the institutional process and requirement verification best practices.

  12. Application of an EPID for fast daily dosimetric quality control of a fully computer-controlled treatment unit

    Energy Technology Data Exchange (ETDEWEB)

    Dirkx, M.L.P.; Kroonwijk, M.; De Boer, J.C.J.; Heijmen, B.J.M. [Nederlands Kanker Inst. `Antoni van Leeuwenhoekhuis`, Amsterdam (Netherlands)

    1995-12-01

    The MM50 Racetrack Microtron, suited for sophisticated three-dimensional computer-controlled conformal radiotherapy techniques, is a complex treatment unit in various respects. Therefore, for a number of gantry angles, daily quality control of the absolute output and the profiles of the scanned photon beams in mandatory. A fast method for these daily checks, based on dosimetric measurements with the Philips SRI-100 Electronic Portal Imaging Device, has been developed and tested. Open beams are checked for four different gantry angles; for gantry angle 0, a wedged field is checked as well. The fields are set up one after another under full computer control. Performing and analyzing the measurements takes about ten minutes. The applied EPID has favourable characteristics for dosimetric quality control measurements: absolute measurements reproduce within 0.5% (1 SD) and the reproducibility of a relative (2-D) fluence profile is 0.2% (1 SD). The day-to-day sensitivity stability over a period of a month is 0.6% (1 SD). EPID-signals are within 0.2% linear with the applied dose. The 2-D fluence profile of the 25 MV photon beam of the MM50 is very stable in time: during a period of one year, a maximum fluctuation of 2.6% was observed. Once, a deviation in the cGy/MU-value of 6% was detected. Only because of the performed morning quality control checks with the EPID, erroneous dose delivery to patients could be avoided; there is no interlock in the MM50-system that would have prevented patient treatment. Based on our experiences and on clinical requirements regarding the acceptability of deviations of beam characteristics, a protocol has been developed including action levels for additional investigations. Studies on the application of the SRI-100 for in vivo dosimetry on the MM50 have been started.

  13. A novel technique for VMAT QA with EPID in cine mode on a Varian TrueBeam linac

    Science.gov (United States)

    Liu, Bo; Adamson, Justus; Rodrigues, Anna; Zhou, Fugen; Yin, Fang-fang; Wu, Qiuwen

    2013-10-01

    Volumetric modulated arc therapy (VMAT) is a relatively new treatment modality for dynamic photon radiation therapy. Pre-treatment quality assurance (QA) is necessary and many efforts have been made to apply electronic portal imaging device (EPID)-based IMRT QA methods to VMAT. It is important to verify the gantry rotation speed during delivery as this is a new variable that is also modulated in VMAT. In this paper, we present a new technique to perform VMAT QA using an EPID. The method utilizes EPID cine mode and was tested on Varian TrueBeam in research mode. The cine images were acquired during delivery and converted to dose matrices after profile correction and dose calibration. A sub-arc corresponding to each cine image was extracted from the original plan and its portal image prediction was calculated. Several analyses were performed including 3D γ analysis (2D images + gantry angle axis), 2D γ analysis, and other statistical analyses. The method was applied to 21 VMAT photon plans of 3 photon energies. The accuracy of the cine image information was investigated. Furthermore, this method's sensitivity to machine delivery errors was studied. The pass rate (92.8 ± 1.4%) for 3D γ analysis was comparable to those from Delta4 system (99.9 ± 0.1%) under similar criteria (3%, 3 mm, 5% threshold and 2° angle to agreement) at 6 MV. The recorded gantry angle and start/stop MUs were found to have sufficient accuracy for clinical QA. Machine delivery errors can be detected through combined analyses of 3D γ, gantry angle, and percentage dose difference. In summary, we have developed and validated a QA technique that can simultaneously verify the gantry angle and delivered MLC fluence for VMAT treatment.This technique is efficient and its accuracy is comparable to other QA methods.

  14. A novel technique for VMAT QA with EPID in cine mode on a Varian TrueBeam linac.

    Science.gov (United States)

    Liu, Bo; Adamson, Justus; Rodrigues, Anna; Zhou, Fugen; Yin, Fang-fang; Wu, Qiuwen

    2013-10-07

    Volumetric modulated arc therapy (VMAT) is a relatively new treatment modality for dynamic photon radiation therapy. Pre-treatment quality assurance (QA) is necessary and many efforts have been made to apply electronic portal imaging device (EPID)-based IMRT QA methods to VMAT. It is important to verify the gantry rotation speed during delivery as this is a new variable that is also modulated in VMAT. In this paper, we present a new technique to perform VMAT QA using an EPID. The method utilizes EPID cine mode and was tested on Varian TrueBeam in research mode. The cine images were acquired during delivery and converted to dose matrices after profile correction and dose calibration. A sub-arc corresponding to each cine image was extracted from the original plan and its portal image prediction was calculated. Several analyses were performed including 3D γ analysis (2D images + gantry angle axis), 2D γ analysis, and other statistical analyses. The method was applied to 21 VMAT photon plans of 3 photon energies. The accuracy of the cine image information was investigated. Furthermore, this method's sensitivity to machine delivery errors was studied. The pass rate (92.8 ± 1.4%) for 3D γ analysis was comparable to those from Delta(4) system (99.9 ± 0.1%) under similar criteria (3%, 3 mm, 5% threshold and 2° angle to agreement) at 6 MV. The recorded gantry angle and start/stop MUs were found to have sufficient accuracy for clinical QA. Machine delivery errors can be detected through combined analyses of 3D γ, gantry angle, and percentage dose difference. In summary, we have developed and validated a QA technique that can simultaneously verify the gantry angle and delivered MLC fluence for VMAT treatment.This technique is efficient and its accuracy is comparable to other QA methods.

  15. aSi-EPID transit signal calibration for dynamic beams: a needful step for the IMRT in vivo dosimetry.

    Science.gov (United States)

    Greco, Francesca; Piermattei, Angelo; Azario, Luigi; Placidi, Lorenzo; Cilla, Savino; Caivano, Rocchina; Fusco, Vincenzo; Fidanzio, Andrea

    2013-10-01

    This work reports a method based on correlation functions to convert EPID transit signals into in vivo dose values at the isocenter point, D iso, of dynamic IMRT beams supplied by Varian linac. Dose reconstruction for intensity-modulated beams required significant corrections of EPID response, due to the X-ray component transmitted through multileaf collimator. The algorithm was formulated using a set of simulated IMRT beams. The beams were parameterized by means of a fluence inhomogeneity index, FI, introduced to describe the degree of beam modulation with respect to open beams. This way, all dosimetric parameters involved in D iso reconstruction algorithm, such as the correlation functions, the correction factor for EPID to phantom distance and the modulated tissue maximum ratios, were determined as a function of the FI index. Clinical IMRT beams were used to irradiate a homogeneous phantom, and for each beam, the agreement between the reconstructed dose, D iso, and the dose computed by TPS, D iso,TPS, was well within 5 %. Moreover, the average ratios, R, between the D iso, and D iso,TPS, resulted equal to 1.002 ± 0.030. Thirty-five IMRT fields of 5 different patients undergoing radiotherapy for head-neck tumors were tested and the results were displayed on a computer screen after 2 min from the end of the treatment. However, 350 in vivo tests supplied an average ratio R equal to 1.004 ± 0.040. The in vivo dosimetry procedure here presented is among the objectives of a National Project financially supported by the Istituto Nazionale di Fisica Nucleare for the development of in vivo dosimetry procedures (Piermattei et al. in Nucl Instrum Methods Phys Res B 274:42-50, 2012) connected to the Record-Verify system of the radiotherapy center.

  16. 2D EPID dose calibration for pretreatment quality control of conformal and IMRT fields: A simple and fast convolution approach.

    Science.gov (United States)

    Camilleri, Jérémy; Mazurier, Jocelyne; Franck, Denis; Dudouet, Philippe; Latorzeff, Igor; Franceries, Xavier

    2016-01-01

    This work presents an original algorithm that converts the signal of an electronic portal imaging device (EPID) into absorbed dose in water at the depth of maximum. The model includes a first image pre-processing step that accounts for the non-uniformity of the detector response but also for the perturbation of the signal due to backscatter radiation. Secondly, the image is converted into absorbed dose to water through a linear conversion function associated with a dose redistribution kernel. These two computation parameters were modelled by correlating the on-axis EPID signal with absorbed dose measurements obtained on square fields by using an ionization chamber placed in water at the depth of maximum dose. The accuracy of the algorithm was assessed by comparing the dose determined from the EPID signal with the dose derived by the treatment planning system (TPS) using the ϒ-index. These comparisons were performed on 8 conformal radiotherapy treatment fields (3DCRT) and 18 modulated fields (IMRT). For a dose difference and a distance-to-agreement set to 3% of the maximum dose and 2 mm respectively, the mean percentage of points with a ϒ-value less than or equal to 1 was 99.8% ± 0.1% for 3DCRT fields and 96.8% ± 2.7% for IMRT fields. Moreover, the mean gamma values were always less than 0.5 whatever the treatment technique. These results confirm that our algorithm is an accurate and suitable tool for clinical use in a context of IMRT quality assurance programmes. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  17. SU-E-T-773: Use of a Commercial TPS for Deriving Exit Dose Distribution for Patient Specific QA with An EPID

    Energy Technology Data Exchange (ETDEWEB)

    Haering, P; Lang, C; Splinter, M [DKFZ, Heidelberg, DE (Germany)

    2015-06-15

    Purpose: A method to derive exit dose distributions with a commercial treatment planning system for comparison to Epid measured doses. Methods: In contrast to published methods, we present an approach that uses a treatment planning system (Raystation, Raysearch) to calculate exit dose patterns based on a modified patient CT dataset. The EPID is assumed as water equivalent and therefore is represented as water filled ring in the images. This is done by: -Export a renamed copy of the patient CT and plan data set. —Manipulate the CT-data to a field of view of 1000 mm. — Insert the water filled cylinder ring, centered to the target point. — Manipulate plan file with the new target and dose prescription point. — Import and recalculate dose on the manipulated data set. — Export and extract exit field dose matrix from the cylinder (optional entrance dose). — Calibrate matrix to size and rebin data from the cylinder to EPID equivalent data. — Correct Epid measurement for scatter, position and field size. -Evaluate and compare data in Verisoft (PTW). Data manipulation and extraction is done by a simple tool (IDL, Exelis). Results: This method was tested on a Siemens Artiste 6MV for field sizes up to 27×27cm2 limited by used geometry and EPID size. First phantom measurements show good results for fields up to 20×20cm (pass rate > 95% for 3%, 3mm Gamma index) while larger fields have higher discrepancies towards the field edges. This might Result from off axis softening of the beam and the higher sensitivity of the detector to beam scatter. Conclusion: This method might simplify the use of exit dosimetry with the EPID for patient specific QA as it uses the dose calculation of a commercial treatment planning system. The concept was proven by phantom data sets, giving acceptable results.

  18. Open verification methodology cookbook

    CERN Document Server

    Glasser, Mark

    2009-01-01

    Functional verification is an art as much as a science. It requires not only creativity and cunning, but also a clear methodology to approach the problem. The Open Verification Methodology (OVM) is a leading-edge methodology for verifying designs at multiple levels of abstraction. It brings together ideas from electrical, systems, and software engineering to provide a complete methodology for verifying large scale System-on-Chip (SoC) designs. OVM defines an approach for developing testbench architectures so they are modular, configurable, and reusable. This book is designed to help both novic

  19. Verification of dose distributions of intensity-modulated radiotherapy beams using a portal imaging device; Caracterizacion de un sistema de imagen portal basado en silicio amorfo para la medida de distribuciones de dosis absorbida

    Energy Technology Data Exchange (ETDEWEB)

    Perez Moreno, J. M.; Fernandez Leton, J. P.; Zucca Aparicio, D.; Garcia Ruiz-Zorrila, J.; Minambres Moro, A.

    2011-07-01

    We have developed a method for using a portal imaging device based on amorphous silicon (EPID) for the dosimetric verification of intensity modulated radiotherapy (IMRT) treatments using 6 MV beams. The images obtained using the imaging system are de convolved with a kernel for radiation and scattering of light generated in the EPID. This kernel has an analytical form and has been experimentally determined. The fluence thus obtained is convolved with a dose deposition kernel, also modeled analytically in a empirical way. The result is an absorbed dose distribution in water at 5 cm depth. The difference between the measured dose using portal imaging device and ionization chamber is -0.3 {+-} 0.9 % in open fields, with a maximum deviation of 1.5% in a 20 cm X 20 cm field with 60 degree centigrade virtual wedge. The degree of agreement between dose distributions measured with the EPID and ionization chamber array is satisfactory, exceeding all cases evaluated 95% of points with {gamma} < 1 using 3%, 3 mm criteria for gamma analysis. (Author) 25 refs.

  20. Quasi 3D dosimetry (EPID, conventional 2D/3D detector matrices)

    Science.gov (United States)

    Bäck, A.

    2015-01-01

    Patient specific pretreatment measurement for IMRT and VMAT QA should preferably give information with a high resolution in 3D. The ability to distinguish complex treatment plans, i.e. treatment plans with a difference between measured and calculated dose distributions that exceeds a specified tolerance, puts high demands on the dosimetry system used for the pretreatment measurements and the results of the measurement evaluation needs a clinical interpretation. There are a number of commercial dosimetry systems designed for pretreatment IMRT QA measurements. 2D arrays such as MapCHECK® (Sun Nuclear), MatriXXEvolution (IBA Dosimetry) and OCTAVIOUS® 1500 (PTW), 3D phantoms such as OCTAVIUS® 4D (PTW), ArcCHECK® (Sun Nuclear) and Delta4 (ScandiDos) and software for EPID dosimetry and 3D reconstruction of the dose in the patient geometry such as EPIDoseTM (Sun Nuclear) and Dosimetry CheckTM (Math Resolutions) are available. None of those dosimetry systems can measure the 3D dose distribution with a high resolution (full 3D dose distribution). Those systems can be called quasi 3D dosimetry systems. To be able to estimate the delivered dose in full 3D the user is dependent on a calculation algorithm in the software of the dosimetry system. All the vendors of the dosimetry systems mentioned above provide calculation algorithms to reconstruct a full 3D dose in the patient geometry. This enables analyzes of the difference between measured and calculated dose distributions in DVHs of the structures of clinical interest which facilitates the clinical interpretation and is a promising tool to be used for pretreatment IMRT QA measurements. However, independent validation studies on the accuracy of those algorithms are scarce. Pretreatment IMRT QA using the quasi 3D dosimetry systems mentioned above rely on both measurement uncertainty and accuracy of calculation algorithms. In this article, these quasi 3D dosimetry systems and their use in patient specific pretreatment IMRT

  1. The implementation in-house dose verification for IMRT and VMAT on breast cancer and NPC cases

    Science.gov (United States)

    Azzi, A.; Dimitri, F. Y.; Pawiro, S. A.

    2016-03-01

    IMRT and VMAT have been widely implemented on breast cancer and NPC cases. Dose verification was conducted to ensure the comparison between dose delivered and prescribe dose in TPS to obtain optimal results and the dose delivered. The gafchromic films measurement was done for breast and NPC simulation on RANDO Phantom, irradiating film by 6 MV photon with 200 cGy and scanned with EPSON V700 using 72 dpi. Dose distribution was calculated using the MATLAB-based in-house algorithm. In order to evaluate the gamma index, gafchromic films and MatriXX 2D array were placed in the Multi Cube and irradiated with EPID in same position. Dose distribution differences for IMRT and VMAT with modalities to TPS on film was 5.34% and 6.68% for NPC PTV70; 12.81% and 6.15% for NPC PTV50; 11.14% and 10.80% for breast cancer. Gamma index differences on IMRT with modalities to MatriXX 2D array and EPID was -0.09% and 5.13% for NPC; 0.51% and 2.28% for breast cancer. On the other hand, gamma index difference on VMAT was -1.65% and 1.43% for NPC; 0.19% and 4.38% for breast cancer. This measurement method can be used to verify dose for breast cancer and NPC cases in IMRT and VMAT.

  2. Quantitative Verification in Practice

    NARCIS (Netherlands)

    Haverkort, Boudewijn R.; Katoen, Joost-Pieter; Larsen, Kim G.

    2010-01-01

    Soon after the birth of model checking, the first theoretical achievements have been reported on the automated verification of quanti- tative system aspects such as discrete probabilities and continuous time. These theories have been extended in various dimensions, such as con- tinuous probabilities

  3. Verification in referral-based crowdsourcing.

    Directory of Open Access Journals (Sweden)

    Victor Naroditskiy

    Full Text Available Online social networks offer unprecedented potential for rallying a large number of people to accomplish a given task. Here we focus on information gathering tasks where rare information is sought through "referral-based crowdsourcing": the information request is propagated recursively through invitations among members of a social network. Whereas previous work analyzed incentives for the referral process in a setting with only correct reports, misreporting is known to be both pervasive in crowdsourcing applications, and difficult/costly to filter out. A motivating example for our work is the DARPA Red Balloon Challenge where the level of misreporting was very high. In order to undertake a formal study of verification, we introduce a model where agents can exert costly effort to perform verification and false reports can be penalized. This is the first model of verification and it provides many directions for future research, which we point out. Our main theoretical result is the compensation scheme that minimizes the cost of retrieving the correct answer. Notably, this optimal compensation scheme coincides with the winning strategy of the Red Balloon Challenge.

  4. Estudio de un brote epidémico de tos ferina en Castellón

    Directory of Open Access Journals (Sweden)

    González Morán Francisco

    2002-01-01

    Full Text Available Fundamento: A partir de la declaración de varios casos en un centro escolar se inicia el estudio de brote con el objetivo de caracterizar éste desde el punto de vista de persona, lugar y tiempo; se calcula la efectividad de la vacuna, y se estudia la concordancia entre los casos y el resultado positivo del estudio serológico. Métodos: Se define caso a la persona que presenta tos persistente de dos semanas de duración. Se realiza estudio de la difusión de la enfermedad a través de la curva epidémica, y de la efectividad de la dosis de refuerzo de la vacuna antipertussis. La concordancia entre los casos y la serología positiva se evalúa por el índice Kappa. Resultados: Entre los alumnos de varios centros escolares y sus convivientes se encuesta a 130 personas, de los que 94 entran en la definición de caso. La media de edad de los casos es 10,5 años, un 42,6% son varones, el 84% escolares, el 71,3% muestra signos de infección reciente (IgM positiva, y el tiempo medio desde la última dosis de vacuna antipertussis es de 8,25 años. La efectividad de la dosis de refuerzo de la vacuna es del 66%. La concordancia entre los casos y el resultado positivo de la serología muestra un Kappa igual a 0,45. No se aisló B. Pertussis en las 25 muestras de frotis faríngeo. Conclusiones: Las aulas y el medio familiar son un factor de difusión de la enfermedad. La inclusión de una dosis de refuerzo a los 18 meses mejora la efectividad de la vacuna antipertussis. El aislamiento de la B. Pertussis es poco frecuente, y la serología, puede ser una alternativa ante la sospecha clínica de la enfermedad.

  5. Spherical coverage verification

    CERN Document Server

    Petkovic, Marko D; Latecki, Longin Jan

    2011-01-01

    We consider the problem of covering hypersphere by a set of spherical hypercaps. This sort of problem has numerous practical applications such as error correcting codes and reverse k-nearest neighbor problem. Using the reduction of non degenerated concave quadratic programming (QP) problem, we demonstrate that spherical coverage verification is NP hard. We propose a recursive algorithm based on reducing the problem to several lower dimension subproblems. We test the performance of the proposed algorithm on a number of generated constellations. We demonstrate that the proposed algorithm, in spite of its exponential worst-case complexity, is applicable in practice. In contrast, our results indicate that spherical coverage verification using QP solvers that utilize heuristics, due to numerical instability, may produce false positives.

  6. Distorted Fingerprint Verification System

    Directory of Open Access Journals (Sweden)

    Divya KARTHIKAESHWARAN

    2011-01-01

    Full Text Available Fingerprint verification is one of the most reliable personal identification methods. Fingerprint matching is affected by non-linear distortion introduced in fingerprint impression during the image acquisition process. This non-linear deformation changes both the position and orientation of minutiae. The proposed system operates in three stages: alignment based fingerprint matching, fuzzy clustering and classifier framework. First, an enhanced input fingerprint image has been aligned with the template fingerprint image and matching score is computed. To improve the performance of the system, a fuzzy clustering based on distance and density has been used to cluster the feature set obtained from the fingerprint matcher. Finally a classifier framework has been developed and found that cost sensitive classifier produces better results. The system has been evaluated on fingerprint database and the experimental result shows that system produces a verification rate of 96%. This system plays an important role in forensic and civilian applications.

  7. An initial study on the estimation of time-varying volumetric treatment images and 3D tumor localization from single MV cine EPID images.

    Science.gov (United States)

    Mishra, Pankaj; Li, Ruijiang; Mak, Raymond H; Rottmann, Joerg; Bryant, Jonathan H; Williams, Christopher L; Berbeco, Ross I; Lewis, John H

    2014-08-01

    In this work the authors develop and investigate the feasibility of a method to estimate time-varying volumetric images from individual MV cine electronic portal image device (EPID) images. The authors adopt a two-step approach to time-varying volumetric image estimation from a single cine EPID image. In the first step, a patient-specific motion model is constructed from 4DCT. In the second step, parameters in the motion model are tuned according to the information in the EPID image. The patient-specific motion model is based on a compact representation of lung motion represented in displacement vector fields (DVFs). DVFs are calculated through deformable image registration (DIR) of a reference 4DCT phase image (typically peak-exhale) to a set of 4DCT images corresponding to different phases of a breathing cycle. The salient characteristics in the DVFs are captured in a compact representation through principal component analysis (PCA). PCA decouples the spatial and temporal components of the DVFs. Spatial information is represented in eigenvectors and the temporal information is represented by eigen-coefficients. To generate a new volumetric image, the eigen-coefficients are updated via cost function optimization based on digitally reconstructed radiographs and projection images. The updated eigen-coefficients are then multiplied with the eigenvectors to obtain updated DVFs that, in turn, give the volumetric image corresponding to the cine EPID image. The algorithm was tested on (1) Eight digital eXtended CArdiac-Torso phantom datasets based on different irregular patient breathing patterns and (2) patient cine EPID images acquired during SBRT treatments. The root-mean-squared tumor localization error is (0.73 ± 0.63 mm) for the XCAT data and (0.90 ± 0.65 mm) for the patient data. The authors introduced a novel method of estimating volumetric time-varying images from single cine EPID images and a PCA-based lung motion model. This is the first method to estimate

  8. An initial study on the estimation of time-varying volumetric treatment images and 3D tumor localization from single MV cine EPID images

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Pankaj, E-mail: pankaj.mishra@varian.com; Mak, Raymond H.; Rottmann, Joerg; Bryant, Jonathan H.; Williams, Christopher L.; Berbeco, Ross I.; Lewis, John H. [Brigham and Women' s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States); Li, Ruijiang [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305 (United States)

    2014-08-15

    Purpose: In this work the authors develop and investigate the feasibility of a method to estimate time-varying volumetric images from individual MV cine electronic portal image device (EPID) images. Methods: The authors adopt a two-step approach to time-varying volumetric image estimation from a single cine EPID image. In the first step, a patient-specific motion model is constructed from 4DCT. In the second step, parameters in the motion model are tuned according to the information in the EPID image. The patient-specific motion model is based on a compact representation of lung motion represented in displacement vector fields (DVFs). DVFs are calculated through deformable image registration (DIR) of a reference 4DCT phase image (typically peak-exhale) to a set of 4DCT images corresponding to different phases of a breathing cycle. The salient characteristics in the DVFs are captured in a compact representation through principal component analysis (PCA). PCA decouples the spatial and temporal components of the DVFs. Spatial information is represented in eigenvectors and the temporal information is represented by eigen-coefficients. To generate a new volumetric image, the eigen-coefficients are updated via cost function optimization based on digitally reconstructed radiographs and projection images. The updated eigen-coefficients are then multiplied with the eigenvectors to obtain updated DVFs that, in turn, give the volumetric image corresponding to the cine EPID image. Results: The algorithm was tested on (1) Eight digital eXtended CArdiac-Torso phantom datasets based on different irregular patient breathing patterns and (2) patient cine EPID images acquired during SBRT treatments. The root-mean-squared tumor localization error is (0.73 ± 0.63 mm) for the XCAT data and (0.90 ± 0.65 mm) for the patient data. Conclusions: The authors introduced a novel method of estimating volumetric time-varying images from single cine EPID images and a PCA-based lung motion model

  9. SU-E-T-775: Use of Electronic Portal Imaging Device (EPID) for Quality Assurance (QA) of Electron Beams On Varian Truebeam System

    Energy Technology Data Exchange (ETDEWEB)

    Cai, B; Yaddanapudi, S; Sun, B; Li, H; Noel, C; Mutic, S; Goddu, S [Department of Radiation Oncology, Washington University in St Louis, St. Louis, MO (United States)

    2015-06-15

    Purpose: In a previous study we have demonstrated the feasibility of using EPID to QA electron beam parameters on a single Varian TrueBeam LINAC. This study aims to provide further investigation on (1) reproducibility of using EPID to detect electron beam energy changes on multiple machines and (2) evaluation of appropriate calibration methods to compare results from different EPIDs. Methods: Ad-hoc mode electron beam images were acquired in developer mode with XML code. Electron beam data were collected on a total of six machines from four institutions. A custom-designed double-wedge phantom was placed on the EPID detector. Two calibration methods - Pixel Sensitivity Map (PSM) and Large Source-to-Imager Distance Flood Field (LSID-FF) - were used. To test the sensitivity of EPID in detecting energy drifts, Bending Magnet Current (BMC) was detuned to invoke energy changes corresponding to ∼±1.5 mm change in R50% of PDD on two machines from two institutions. Percent depth ionization (PDI) curves were then analyzed and compared with the respective baseline images using LSID-FF calibration. For reproducibility testing, open field EPID images and images with a standard testing phantom were collected on multiple machines. Images with and without PSM correction for same energies on different machines were overlaid and compared. Results: Two pixel shifts were observed in PDI curve when energy changes exceeded the TG142 tolerance. PSM showed the potential to correct the differences in pixel response of different imagers. With PSM correction, the histogram of images differences obtained from different machines showed narrower distributions than those images without PSM correction. Conclusion: EPID is sensitive for electron energy changes and the results are reproducible on different machines. When overlaying images from different machines, PSM showed the ability to partially eliminate the intrinsic variation of various imagers. Research Funding from Varian Medical Systems

  10. Fast 3D dosimetric verifications based on an electronic portal imaging device using a GPU calculation engine.

    Science.gov (United States)

    Zhu, Jinhan; Chen, Lixin; Chen, Along; Luo, Guangwen; Deng, Xiaowu; Liu, Xiaowei

    2015-04-11

    To use a graphic processing unit (GPU) calculation engine to implement a fast 3D pre-treatment dosimetric verification procedure based on an electronic portal imaging device (EPID). The GPU algorithm includes the deconvolution and convolution method for the fluence-map calculations, the collapsed-cone convolution/superposition (CCCS) algorithm for the 3D dose calculations and the 3D gamma evaluation calculations. The results of the GPU-based CCCS algorithm were compared to those of Monte Carlo simulations. The planned and EPID-based reconstructed dose distributions in overridden-to-water phantoms and the original patients were compared for 6 MV and 10 MV photon beams in intensity-modulated radiation therapy (IMRT) treatment plans based on dose differences and gamma analysis. The total single-field dose computation time was less than 8 s, and the gamma evaluation for a 0.1-cm grid resolution was completed in approximately 1 s. The results of the GPU-based CCCS algorithm exhibited good agreement with those of the Monte Carlo simulations. The gamma analysis indicated good agreement between the planned and reconstructed dose distributions for the treatment plans. For the target volume, the differences in the mean dose were less than 1.8%, and the differences in the maximum dose were less than 2.5%. For the critical organs, minor differences were observed between the reconstructed and planned doses. The GPU calculation engine was used to boost the speed of 3D dose and gamma evaluation calculations, thus offering the possibility of true real-time 3D dosimetric verification.

  11. Robust verification analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rider, William, E-mail: wjrider@sandia.gov [Sandia National Laboratories, Center for Computing Research, Albuquerque, NM 87185 (United States); Witkowski, Walt [Sandia National Laboratories, Verification and Validation, Uncertainty Quantification, Credibility Processes Department, Engineering Sciences Center, Albuquerque, NM 87185 (United States); Kamm, James R. [Los Alamos National Laboratory, Methods and Algorithms Group, Computational Physics Division, Los Alamos, NM 87545 (United States); Wildey, Tim [Sandia National Laboratories, Center for Computing Research, Albuquerque, NM 87185 (United States)

    2016-02-15

    We introduce a new methodology for inferring the accuracy of computational simulations through the practice of solution verification. We demonstrate this methodology on examples from computational heat transfer, fluid dynamics and radiation transport. Our methodology is suited to both well- and ill-behaved sequences of simulations. Our approach to the analysis of these sequences of simulations incorporates expert judgment into the process directly via a flexible optimization framework, and the application of robust statistics. The expert judgment is systematically applied as constraints to the analysis, and together with the robust statistics guards against over-emphasis on anomalous analysis results. We have named our methodology Robust Verification. Our methodology is based on utilizing multiple constrained optimization problems to solve the verification model in a manner that varies the analysis' underlying assumptions. Constraints applied in the analysis can include expert judgment regarding convergence rates (bounds and expectations) as well as bounding values for physical quantities (e.g., positivity of energy or density). This approach then produces a number of error models, which are then analyzed through robust statistical techniques (median instead of mean statistics). This provides self-contained, data and expert informed error estimation including uncertainties for both the solution itself and order of convergence. Our method produces high quality results for the well-behaved cases relatively consistent with existing practice. The methodology can also produce reliable results for ill-behaved circumstances predicated on appropriate expert judgment. We demonstrate the method and compare the results with standard approaches used for both code and solution verification on well-behaved and ill-behaved simulations.

  12. Methods of Software Verification

    Directory of Open Access Journals (Sweden)

    R. E. Gurin

    2015-01-01

    Full Text Available This article is devoted to the problem of software verification (SW. Methods of software verification designed to check the software for compliance with the stated requirements such as correctness, system security and system adaptability to small changes in the environment, portability and compatibility, etc. These are various methods both by the operation process and by the way of achieving result. The article describes the static and dynamic methods of software verification and paid attention to the method of symbolic execution. In its review of static analysis are discussed and described the deductive method, and methods for testing the model. A relevant issue of the pros and cons of a particular method is emphasized. The article considers classification of test techniques for each method. In this paper we present and analyze the characteristics and mechanisms of the static analysis of dependencies, as well as their views, which can reduce the number of false positives in situations where the current state of the program combines two or more states obtained both in different paths of execution and in working with multiple object values. Dependences connect various types of software objects: single variables, the elements of composite variables (structure fields, array elements, the size of the heap areas, the length of lines, the number of initialized array elements in the verification code using static methods. The article pays attention to the identification of dependencies within the framework of the abstract interpretation, as well as gives an overview and analysis of the inference tools.Methods of dynamic analysis such as testing, monitoring and profiling are presented and analyzed. Also some kinds of tools are considered which can be applied to the software when using the methods of dynamic analysis. Based on the work a conclusion is drawn, which describes the most relevant problems of analysis techniques, methods of their solutions and

  13. Linear array measurements of enhanced dynamic wedge and treatment planning system (TPS) calculation for 15 MV photon beam and comparison with electronic portal imaging device (EPID) measurements

    Science.gov (United States)

    Petrovic, Borislava; Grzadziel, Aleksandra; Rutonjski, Laza; Slosarek, Krzysztof

    2010-01-01

    Introduction. Enhanced dynamic wedges (EDW) are known to increase drastically the radiation therapy treatment efficiency. This paper has the aim to compare linear array measurements of EDW with the calculations of treatment planning system (TPS) and the electronic portal imaging device (EPID) for 15 MV photon energy. Materials and methods. The range of different field sizes and wedge angles (for 15 MV photon beam) were measured by the linear chamber array CA 24 in Blue water phantom. The measurement conditions were applied to the calculations of the commercial treatment planning system XIO CMS v.4.2.0 using convolution algorithm. EPID measurements were done on EPID-focus distance of 100 cm, and beam parameters being the same as for CA24 measurements. Results Both depth doses and profiles were measured. EDW linear array measurements of profiles to XIO CMS TPS calculation differ around 0.5%. Profiles in non-wedged direction and open field profiles practically do not differ. Percentage depth doses (PDDs) for all EDW measurements show the difference of not more than 0.2%, while the open field PDD is almost the same as EDW PDD. Wedge factors for 60 deg wedge angle were also examined, and the difference is up to 4%. EPID to linear array differs up to 5%. Conclusions The implementation of EDW in radiation therapy treatments provides clinicians with an effective tool for the conformal radiotherapy treatment planning. If modelling of EDW beam in TPS is done correctly, a very good agreement between measurements and calculation is obtained, but EPID cannot be used for reference measurements. PMID:22933916

  14. Linear array measurements of enhanced dynamic wedge and treatment planning system (TPS) calculation for 15 MV photon beam and comparison with electronic portal imaging device (EPID) measurements.

    Science.gov (United States)

    Petrovic, Borislava; Grzadziel, Aleksandra; Rutonjski, Laza; Slosarek, Krzysztof

    2010-09-01

    Enhanced dynamic wedges (EDW) are known to increase drastically the radiation therapy treatment efficiency. This paper has the aim to compare linear array measurements of EDW with the calculations of treatment planning system (TPS) and the electronic portal imaging device (EPID) for 15 MV photon energy. The range of different field sizes and wedge angles (for 15 MV photon beam) were measured by the linear chamber array CA 24 in Blue water phantom. The measurement conditions were applied to the calculations of the commercial treatment planning system XIO CMS v.4.2.0 using convolution algorithm. EPID measurements were done on EPID-focus distance of 100 cm, and beam parameters being the same as for CA24 measurements. Both depth doses and profiles were measured. EDW linear array measurements of profiles to XIO CMS TPS calculation differ around 0.5%. Profiles in non-wedged direction and open field profiles practically do not differ. Percentage depth doses (PDDs) for all EDW measurements show the difference of not more than 0.2%, while the open field PDD is almost the same as EDW PDD. Wedge factors for 60 deg wedge angle were also examined, and the difference is up to 4%. EPID to linear array differs up to 5%. The implementation of EDW in radiation therapy treatments provides clinicians with an effective tool for the conformal radiotherapy treatment planning. If modelling of EDW beam in TPS is done correctly, a very good agreement between measurements and calculation is obtained, but EPID cannot be used for reference measurements.

  15. Continuous verification using multimodal biometrics.

    Science.gov (United States)

    Sim, Terence; Zhang, Sheng; Janakiraman, Rajkumar; Kumar, Sandeep

    2007-04-01

    Conventional verification systems, such as those controlling access to a secure room, do not usually require the user to reauthenticate himself for continued access to the protected resource. This may not be sufficient for high-security environments in which the protected resource needs to be continuously monitored for unauthorized use. In such cases, continuous verification is needed. In this paper, we present the theory, architecture, implementation, and performance of a multimodal biometrics verification system that continuously verifies the presence of a logged-in user. Two modalities are currently used--face and fingerprint--but our theory can be readily extended to include more modalities. We show that continuous verification imposes additional requirements on multimodal fusion when compared to conventional verification systems. We also argue that the usual performance metrics of false accept and false reject rates are insufficient yardsticks for continuous verification and propose new metrics against which we benchmark our system.

  16. Scalable Techniques for Formal Verification

    CERN Document Server

    Ray, Sandip

    2010-01-01

    This book presents state-of-the-art approaches to formal verification techniques to seamlessly integrate different formal verification methods within a single logical foundation. It should benefit researchers and practitioners looking to get a broad overview of the spectrum of formal verification techniques, as well as approaches to combining such techniques within a single framework. Coverage includes a range of case studies showing how such combination is fruitful in developing a scalable verification methodology for industrial designs. This book outlines both theoretical and practical issue

  17. Meningite meningocócica: avaliação em período pré-epidêmico e epidêmico no Rio de Janeiro (1973-1975

    Directory of Open Access Journals (Sweden)

    Nélson Jerônimo Lourenço

    1975-10-01

    Full Text Available São relatadas observações acumuladas nos períodos pré-epidêmico e epidêmico (1973-1975 do atual surto de meningoencefalite meningocócica na área do Grande Rio, e realizados estudos bacteriológicos baseados em 1.000 casos suspeitos de meningoencefalite e submetidos à punção lombar, no Hospital Estadual São Sebastião. É proposto e discutido esquema simples e eficaz para processamento bacteriológico dos LCR suspeitos, a partir da colheita e pronta semeadura do material. É também discutida a real contribuição da bacterioscopia no diagnóstico presuntivo das meningoencefalites, definindo-se as limitações da técnica. Foi obtido elevado grau de isolamento de microorganismos, variando de 3%, para líquores entre zero e 10 células/mm' e 72%, para líquores acima de 1000 células/mm³. No decorrer do estudo, foram isoladas e caracterizadas 356 amostras bacterianas, assim discriminadas: N. meningitidis, 281; Haemophilus sp., 22; Enterobacteriaceae, 15; D. pneumoniae, 26; bastonetes gram negativos oxidattvos, 3; estreptococo beta hemolitico, 1 e enterococo, 1. As amostras de meningococos eram, em 15% dos casos, do grupo sorológico A, em 2% do grupo B e em 14%, do grupo sorológico C. Os testes de sensibilidade, em disco, aos agentes antimicrobianos principalmente utilizados na quimioprofilaxia e tratamento da doença meningocócica revelaram alto grau de sensibilidade das amostras ensaiadas a todos os agentes testados. A resistência à sulfadiazina sódica, em testes realizados segundo as normas preconizadas pela Food and Drug Administration (F.D.A., revelaram elevado grau de resistência, particularmente dos meningococos do grupo C.

  18. Survey on Offline Finger Print Verification System

    NARCIS (Netherlands)

    Suman, R.; Kaur, R.

    2012-01-01

    The fingerprint verification, means where "verification" implies a user matching a fingerprint against a single fingerprint associated with the identity that the user claims. Biometrics can be classified into two types Behavioral (signature verification, keystroke dynamics, etc.) And Physiological (

  19. Online Gaming

    Directory of Open Access Journals (Sweden)

    Kevin Curran

    2005-01-01

    Full Text Available Computer gaming is a medium by which we can entertain ourselves, a medium that has expanded to the online worldwide market as part as globalization. The growth of online gaming has close ties with the use of broadband, as a good online gaming experience requires a broadband connection. Through online gaming, people can play and communicate with each other freely in almost any country, at any given time. This paper examines the phenomenon of online gaming.

  20. Verification of LHS distributions.

    Energy Technology Data Exchange (ETDEWEB)

    Swiler, Laura Painton

    2006-04-01

    This document provides verification test results for normal, lognormal, and uniform distributions that are used in Sandia's Latin Hypercube Sampling (LHS) software. The purpose of this testing is to verify that the sample values being generated in LHS are distributed according to the desired distribution types. The testing of distribution correctness is done by examining summary statistics, graphical comparisons using quantile-quantile plots, and format statistical tests such as the Chisquare test, the Kolmogorov-Smirnov test, and the Anderson-Darling test. The overall results from the testing indicate that the generation of normal, lognormal, and uniform distributions in LHS is acceptable.

  1. High-level verification

    CERN Document Server

    Lerner, Sorin; Kundu, Sudipta

    2011-01-01

    Given the growing size and heterogeneity of Systems on Chip (SOC), the design process from initial specification to chip fabrication has become increasingly complex. This growing complexity provides incentive for designers to use high-level languages such as C, SystemC, and SystemVerilog for system-level design. While a major goal of these high-level languages is to enable verification at a higher level of abstraction, allowing early exploration of system-level designs, the focus so far for validation purposes has been on traditional testing techniques such as random testing and scenario-based

  2. HDL to verification logic translator

    Science.gov (United States)

    Gambles, J. W.; Windley, P. J.

    The increasingly higher number of transistors possible in VLSI circuits compounds the difficulty in insuring correct designs. As the number of possible test cases required to exhaustively simulate a circuit design explodes, a better method is required to confirm the absence of design faults. Formal verification methods provide a way to prove, using logic, that a circuit structure correctly implements its specification. Before verification is accepted by VLSI design engineers, the stand alone verification tools that are in use in the research community must be integrated with the CAD tools used by the designers. One problem facing the acceptance of formal verification into circuit design methodology is that the structural circuit descriptions used by the designers are not appropriate for verification work and those required for verification lack some of the features needed for design. We offer a solution to this dilemma: an automatic translation from the designers' HDL models into definitions for the higher-ordered logic (HOL) verification system. The translated definitions become the low level basis of circuit verification which in turn increases the designer's confidence in the correctness of higher level behavioral models.

  3. HDL to verification logic translator

    Science.gov (United States)

    Gambles, J. W.; Windley, P. J.

    1992-01-01

    The increasingly higher number of transistors possible in VLSI circuits compounds the difficulty in insuring correct designs. As the number of possible test cases required to exhaustively simulate a circuit design explodes, a better method is required to confirm the absence of design faults. Formal verification methods provide a way to prove, using logic, that a circuit structure correctly implements its specification. Before verification is accepted by VLSI design engineers, the stand alone verification tools that are in use in the research community must be integrated with the CAD tools used by the designers. One problem facing the acceptance of formal verification into circuit design methodology is that the structural circuit descriptions used by the designers are not appropriate for verification work and those required for verification lack some of the features needed for design. We offer a solution to this dilemma: an automatic translation from the designers' HDL models into definitions for the higher-ordered logic (HOL) verification system. The translated definitions become the low level basis of circuit verification which in turn increases the designer's confidence in the correctness of higher level behavioral models.

  4. Generic System Verilog Universal Verification Methodology Based Reusable Verification Environment for Efficient Verification of Image Signal Processing IPS/SOCS

    Directory of Open Access Journals (Sweden)

    Abhishek Jain

    2012-12-01

    Full Text Available In this paper, we present Generic System Verilog Universal Verification Methodology based Reusable Verification Environment for efficient verification of Image Signal Processing IP’s/SoC’s. With the tight schedules on all projects it is important to have a strong verification methodology which contributes to First Silicon Success. Deploy methodologies which enforce full functional coverage and verification of corner cases through pseudo random test scenarios is required. Also, standardization of verification flow is needed. Previously, inside imaging group of ST, Specman (e/Verilog based Verification Environment forIP/Subsystem level verification and C/C++/Verilog based Directed Verification Environment for SoC Level Verification was used for Functional Verification. Different Verification Environments were used at IP level and SoC level. Different Verification/Validation Methodologies were used for SoC Verification across multiple sites. Verification teams were also looking for the ways how to catch bugs early in the design cycle? Thus, Generic System Verilog Universal Verification Methodology (UVM based Reusable Verification Environment is required to avoid the problem of having so many methodologies and provides a standard unified solution which compiles on all tools.

  5. Clinical Verification of Homeopathy

    Directory of Open Access Journals (Sweden)

    Michel Van Wassenhoven

    2011-07-01

    Full Text Available The world is changing! This is certainly true regarding the homeopathic practice and access to homeopathic medicine. Therefore our first priority at the ECH-LMHI [1] has been to produce a yearly report on the scientific framework of homeopathy. In the 2010 version a new chapter about epidemic diseases has been added including the Leptospirosis survey on the Cuban population. A second priority has been to review the definition of the homeopathic medicines respecting the new framework generated by the official registration procedure and the WHO report. We are working now on a documented (Materia Medica and provings list of homeopathic remedies to facilitate the registration of our remedies. The new challenges are: first of all more good research proposals and as such more funding (possible through ISCHI + Blackie Foundation as examples [2]; international acceptance of new guidelines for proving and clinical verification of homeopathic symptoms (Proposals are ready for discussion; total reconsideration of the homeopathic repertories including results of the clinical verification of the symptoms. The world is changing, we are part of the world and changes are needed also for homeopathy!

  6. Shift Verification and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Pandya, Tara M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Evans, Thomas M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Davidson, Gregory G [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Seth R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Godfrey, Andrew T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-07

    This documentation outlines the verification and validation of Shift for the Consortium for Advanced Simulation of Light Water Reactors (CASL). Five main types of problems were used for validation: small criticality benchmark problems; full-core reactor benchmarks for light water reactors; fixed-source coupled neutron-photon dosimetry benchmarks; depletion/burnup benchmarks; and full-core reactor performance benchmarks. We compared Shift results to measured data and other simulated Monte Carlo radiation transport code results, and found very good agreement in a variety of comparison measures. These include prediction of critical eigenvalue, radial and axial pin power distributions, rod worth, leakage spectra, and nuclide inventories over a burn cycle. Based on this validation of Shift, we are confident in Shift to provide reference results for CASL benchmarking.

  7. Shift Verification and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Pandya, Tara M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Evans, Thomas M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Davidson, Gregory G [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Seth R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Godfrey, Andrew T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-07

    This documentation outlines the verification and validation of Shift for the Consortium for Advanced Simulation of LightWater Reactors (CASL). Fivemain types of problems were used for validation: small criticality benchmark problems; full-core reactor benchmarks for light water reactors; fixed source coupled neutron-photon dosimetry benchmarks; depletion/burnup benchmarks; and full-core reactor performance benchmarks. We compared Shift results to measured data and other simulated Monte Carlo radiation transport code results and found very good agreement in a variety of comparison measures. These include prediction of critical eigenvalue, radial and axial pin power distributions, rod worth, leakage spectra, and nuclide inventories over a burn cycle. Based on this validation of Shift, we are confident in Shift to provide reference results for CASL benchmarking.

  8. Reduction of the effect of non-uniform backscatter from an E-type support arm of a Varian a-Si EPID used for dosimetry.

    Science.gov (United States)

    Rowshanfarzad, Pejman; Sabet, Mahsheed; O'Connor, Daryl J; Greer, Peter B

    2010-11-21

    Backscatter from the metallic components in the support arm is one of the sources of inaccuracy in dosimetry with Varian amorphous silicon electronic portal imaging devices (a-Si EPIDs). In this study, the non-uniform arm backscatter is blocked by adding lead sheets between the EPID and an E-type support arm. By comparing the EPID responses on and off the arm, with and without lead and considering the extra weight on the imager, 2 mm of lead was determined as the optimum thickness for both 6 and 18 MV beam energies. The arm backscatter at the central axis with the 2 mm lead in place decreased to 0.1% and 0.2% for the largest field size of 30 × 30 cm(2) using 6 and 18 MV beams, from 2.3% and 1.3% without lead. Changes in the source-to-detector distance (SDD) did not affect the backscatter component more than 1%. The symmetry of the in-plane profiles improved for all field sizes for both beam energies. The addition of lead decreased the contrast-to-noise ratio and resolution by 1.3% and 0.84% for images taken in 6 MV and by 0.5% and 0.38% for those in 18 MV beams. The displacement of the EPID central pixel was measured during a 360° gantry rotation with and without lead which was 1 pixel different. While the backscatter reduces with increasing lead thickness, a 2 mm lead sheet seems sufficient for acceptable dosimetry results without any major degradation to the routine performance of the imager. No increase in patient skin dose was detected.

  9. Amorphous silicon EPID calibration for dosimetric applications: comparison of a method based on Monte Carlo prediction of response with existing techniques

    Energy Technology Data Exchange (ETDEWEB)

    Parent, L [Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton (United Kingdom); Fielding, A L [School of Physical and Chemical Sciences, Queensland University of Technology, Brisbane (Australia); Dance, D R [Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, London (United Kingdom); Seco, J [Department of Radiation Oncology, Francis Burr Proton Therapy Center, Massachusetts General Hospital, Harvard Medical School, Boston (United States); Evans, P M [Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton (United Kingdom)

    2007-07-21

    For EPID dosimetry, the calibration should ensure that all pixels have a similar response to a given irradiation. A calibration method (MC), using an analytical fit of a Monte Carlo simulated flood field EPID image to correct for the flood field image pixel intensity shape, was proposed. It was compared with the standard flood field calibration (FF), with the use of a water slab placed in the beam to flatten the flood field (WS) and with a multiple field calibration where the EPID was irradiated with a fixed 10 x 10 field for 16 different positions (MF). The EPID was used in its normal configuration (clinical setup) and with an additional 3 mm copper slab (modified setup). Beam asymmetry measured with a diode array was taken into account in MC and WS methods. For both setups, the MC method provided pixel sensitivity values within 3% of those obtained with the MF and WS methods (mean difference <1%, standard deviation <2%). The difference of pixel sensitivity between MC and FF methods was up to 12.2% (clinical setup) and 11.8% (modified setup). MC calibration provided images of open fields (5 x 5 to 20 x 20 cm{sup 2}) and IMRT fields to within 3% of that obtained with WS and MF calibrations while differences with images calibrated with the FF method for fields larger than 10 x 10 cm{sup 2} were up to 8%. MC, WS and MF methods all provided a major improvement on the FF method. Advantages and drawbacks of each method were reviewed.

  10. Online reklama

    OpenAIRE

    Švarc, Ondřej

    2016-01-01

    This thesis is thematically focused on online advertising. The paper describes the history of online advertising and its advantages and disadvantages compared to other media types. There are mentioned standards of online advertising on the Czech Internet and ways to optimize the different types for better performance. Next we go over the characteristics of selected tools for assessing the success and management of online campaigns. We also compare the advertising possibilities ...

  11. 40 CFR 1065.307 - Linearity verification.

    Science.gov (United States)

    2010-07-01

    ... linearity verification generally consists of introducing a series of at least 10 reference values to a... reference values of the linearity verification. For pressure, temperature, dewpoint, and GC-ECD linearity verifications, we recommend at least three reference values. For all other linearity verifications select...

  12. Reconfigurable system design and verification

    CERN Document Server

    Hsiung, Pao-Ann; Huang, Chun-Hsian

    2009-01-01

    Reconfigurable systems have pervaded nearly all fields of computation and will continue to do so for the foreseeable future. Reconfigurable System Design and Verification provides a compendium of design and verification techniques for reconfigurable systems, allowing you to quickly search for a technique and determine if it is appropriate to the task at hand. It bridges the gap between the need for reconfigurable computing education and the burgeoning development of numerous different techniques in the design and verification of reconfigurable systems in various application domains. The text e

  13. La teoría epidémica en la literatura sobre la Ley de Lotka Epidemic Theory in the literature on Lotka's law

    Directory of Open Access Journals (Sweden)

    Rubén Urbizagástegui Alvarado

    2008-12-01

    Full Text Available El objetivo de este trabajo es estudiar el modelo epidémico como un proceso determinístico representado por un sistema de ecuaciones diferenciales. Este modelo es después aplicado a los autores productores de literatura sobre la Ley de Lotka desde 1922 hasta 2005. Se observa que esta sub-área de la bibliometría entró en un proceso epidémico a partir de 1965, que éste tiene una alta tasa de autores transeúntes, y que los autores que publican en idiomas diferentes al inglés encontraron el área ya en un estado epidémico.The objective of the present study is to analyse the epidemic model as a deterministic process represented by a system of differential equations and apply it to authors producing literature on Lotka's law from 1922 to 2005. An epidemic process starting in 1965 and showing a high rate or transient authors is observed. Those authors publishing in languages different from English found the area already infected.

  14. Kinship Verification Using Facial Images by Robust Similarity Learning

    Directory of Open Access Journals (Sweden)

    Min Xu

    2016-01-01

    Full Text Available Kinship verification from face images is a new and challenging problem in pattern recognition and computer vision, and it has many potential real-world applications including social media analysis and children adoptions. Most existing methods for kinship verification assume that each positive pair of face images (with kin relationship has greater similarity score than those of negative pairs without kin relationships under a distance metric to be learned. In practice, however, this assumption is usually too strict for real-life kin samples. Instead, we propose in this paper learning a robust similarity model, under which the similarity score of each positive pair is greater than average similarity score of some negative ones. In addition, we develop an online similarity learning algorithm for more scalable application. We empirically evaluate the proposed methods on benchmark datasets, and experimental results show that our method outperforms some state-of-the-art kinship verification methods in terms of verification accuracy and computational efficiency.

  15. Brote epidémico de neumonías por Legionella pneumophila en niños cubanos

    Directory of Open Access Journals (Sweden)

    Roberto Razón Behar

    2002-09-01

    Full Text Available La Legionella pneumophila es uno de los patógenos responsable de neumonías atípicas, a través de la inhalación de aerosoles o aspiración de líquidos infectados. Se detectó un brote epidémico de neumonías por Legionella, originado por la aspiración de agua contaminada de una piscina en un grupo de niños cubanos. El agente causal se identificó en 5 de 9 pacientes, por la técnica de inmunofluorescencia indirecta en muestras de sueros pareados. Los síntomas y signos más frecuentes fueron malestar general, anorexia, astenia, fiebre persistente de 39 °C a 40 °C (103 °F a 105 °F, mialgias, cefaleas, náuseas, vómitos, dolor abdominal, diarreas, tos húmeda, dolor torácico y polipnea. Durante el desarrollo de la enfermedad, el tratamiento antibiótico fue empírico (incluyendo los macrólidos, por no tener confirmado el diagnóstico. Todos los pacientes evolucionaron satisfactoriamente. Se reportó un brote epidémico de neumonías por Legionella en niños por primera vez en Cuba, lo cual tiene importancia clínica y epidemiológica.The legionella pneumophila is one of the pathogens responsible for atypic pneumonias by the inhalation of aerosols or aspiration of infected liquids. An epidemic outbreak of pneumonias caused by Legionella was detected among a group of Cuban children. It was originated by the aspiration of contaminated water in a swimming pool. The causal agent was identified in 5 of 9 patients by using the indirect immunofluorescence technique in samples of matched sera. The most frequent symptoms and signs were malaise, anorexia, asthenia, persistent fever from 39°C to 40°C (103° F to 105° F, myalgias, headache, nauseas, vomits, abdominal pain, diarrheas, moist cough, thoracic pain and polypnoea. The antibiotic treatment was empiric (including the macrolides during the development of the disease, since the diagnosis was not confirmed. The patients’ evolution was satisfactory. An epidemic outbreak of pneumonias

  16. Optimization of image quality and dose for Varian aS500 electronic portal imaging devices (EPIDs).

    Science.gov (United States)

    McGarry, C K; Grattan, M W D; Cosgrove, V P

    2007-12-07

    This study was carried out to investigate whether the electronic portal imaging (EPI) acquisition process could be optimized, and as a result tolerance and action levels be set for the PIPSPro QC-3V phantom image quality assessment. The aim of the optimization process was to reduce the dose delivered to the patient while maintaining a clinically acceptable image quality. This is of interest when images are acquired in addition to the planned patient treatment, rather than images being acquired using the treatment field during a patient's treatment. A series of phantoms were used to assess image quality for different acquisition settings relative to the baseline values obtained following acceptance testing. Eight Varian aS500 EPID systems on four matched Varian 600C/D linacs and four matched Varian 2100C/D linacs were compared for consistency of performance and images were acquired at the four main orthogonal gantry angles. Images were acquired using a 6 MV beam operating at 100 MU min(-1) and the low-dose acquisition mode. Doses used in the comparison were measured using a Farmer ionization chamber placed at d(max) in solid water. The results demonstrated that the number of reset frames did not have any influence on the image contrast, but the number of frame averages did. The expected increase in noise with corresponding decrease in contrast was also observed when reducing the number of frame averages. The optimal settings for the low-dose acquisition mode with respect to image quality and dose were found to be one reset frame and three frame averages. All patients at the Northern Ireland Cancer Centre are now imaged using one reset frame and three frame averages in the 6 MV 100 MU min(-1) low-dose acquisition mode. Routine EPID QC contrast tolerance (+/-10) and action (+/-20) levels using the PIPSPro phantom based around expected values of 190 (Varian 600C/D) and 225 (Varian 2100C/D) have been introduced. The dose at dmax from electronic portal imaging has been

  17. Generic interpreters and microprocessor verification

    Science.gov (United States)

    Windley, Phillip J.

    1990-01-01

    The following topics are covered in viewgraph form: (1) generic interpreters; (2) Viper microprocessors; (3) microprocessor verification; (4) determining correctness; (5) hierarchical decomposition; (6) interpreter theory; (7) AVM-1; (8) phase-level specification; and future work.

  18. Biometric verification with correlation filters

    Science.gov (United States)

    Vijaya Kumar, B. V. K.; Savvides, Marios; Xie, Chunyan; Venkataramani, Krithika; Thornton, Jason; Mahalanobis, Abhijit

    2004-01-01

    Using biometrics for subject verification can significantly improve security over that of approaches based on passwords and personal identification numbers, both of which people tend to lose or forget. In biometric verification the system tries to match an input biometric (such as a fingerprint, face image, or iris image) to a stored biometric template. Thus correlation filter techniques are attractive candidates for the matching precision needed in biometric verification. In particular, advanced correlation filters, such as synthetic discriminant function filters, can offer very good matching performance in the presence of variability in these biometric images (e.g., facial expressions, illumination changes, etc.). We investigate the performance of advanced correlation filters for face, fingerprint, and iris biometric verification.

  19. A New Algorithm for On- Line Handwriting Signature Verification Based on Evolutionary Computation

    Institute of Scientific and Technical Information of China (English)

    ZHENG Jianbin; ZHU Guangxi

    2006-01-01

    The paper proposes an on-line signature verification algorithm, through which test sample and template signatures can be optimizedly matched, based on evolutionary computation (EC). Firstly, the similarity of signature curve segment is defined, and shift and scale transforms are also introduced due to the randoness of on-line signature. Secondly,this paper puts forward signature verification matching algorithm after establishment of the mathematical model. Thirdly, the concrete realization of the algorithm based on EC is discussed as well. In addition, the influence of shift and scale on the matching result is fully considered in the algorithm.Finally, a computation example is given, and the matching results between the test sample curve and the template signature curve are analyzed in detail. The preliminary experiments reveal that the type of signature verification problem can be solved by EC.

  20. SU-E-T-80: Comparison of Fluence-Based RapidArc QAs Using EPID and MapCHECK 2

    Energy Technology Data Exchange (ETDEWEB)

    Jin, H; Jesseph, F; Ahmad, S [Oklahoma Univ. Health Science Ctr., Oklahoma City, OK (United States)

    2014-06-01

    Purpose: To compare the Varian aS-1000 EPID imager to the isocentrically mounted MapCHECK 2 diode array for RapidArc QAs as a function of photon beam energy. Methods: A Varian TrueBeam STx with an aS-1000 digital imaging panel was used to acquire RapidArc QA images for 13 patient plans; each plan QA was performed at 6, 8, 10 and 15MV energies. The Portal Dose Image Prediction algorithm in the Varian Eclipse treatment planning system (TPS) was used to create the comparison image for the EPID acquisition. A Sun Nuclear MapCHECK 2 diode array on an isocentric mounting fixture with 5 cm water-equivalent buildup was also used for the RapidArc QAs. A composite dose plane was taken from the Eclipse TPS for comparison to the MapCHECK 2 measurements. A gamma test was implemented in the Sun Nuclear Patient software with 10% threshold and absolute comparison for both QA methods. The two-tailed paired t-test was employed to analyze the statistical significance between two methods at the 95% confidence level. Results: The average gamma passing rates were greater than 95% at 3%/3mm using both methods for all four energies. The average passing rates were within 2.5% and 1.1% of each other when analyzed at 2%/2mm and 3%/3mm conditions, respectively. The EPID passing rates were somewhat better than the MapCHECK 2 when analyzed at 1%/1mm condition; this difference decreased with increasing energy (9.1% at 6MV to 2.7% at 15MV). The differences were not statistically significant for all criteria and energies (p-value ã 0.05). Conclusion: EPID-based RapidArc QA results are comparable to MapCHECK 2 when using 3%/3mm criteria at all four energies. EPID-based QA shows potential for being the superior device under strict gamma criteria.

  1. 75 FR 28673 - Bureau of Verification, Compliance, and Implementation; Termination of Measures Against a Russian...

    Science.gov (United States)

    2010-05-21

    ... determined on May 12, 2010 that sanctions imposed effective October 23, 2008 (73 FR 206) on the Russian... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Bureau of Verification, Compliance, and Implementation; Termination of Measures Against a Russian...

  2. TRACEABILITY OF PRECISION MEASUREMENTS ON COORDINATE MEASURING MACHINES – PERFORMANCE VERIFICATION OF CMMs

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Sobiecki, René; Tosello, Guido

    This document is used in connection with one exercise of 30 minutes duration as a part of the course VISION ONLINE – One week course on Precision & Nanometrology. The exercise concerns performance verification of the volumetric measuring capability of a small volume coordinate measuring machine. ....... This section contains reference to the American standard normative ANSI/ASME and a description of the exercise....

  3. Image guided position verification for intensity modulated radiotherapy of prostate cancer

    NARCIS (Netherlands)

    Nederveen, A.J.

    2002-01-01

    The aim of this thesis is to provide a practical framework for dose escalation in the prostate using intensity modulated radiotherapy (IMRT) and to find out if marker based on-line position verification is clinically feasible and effective. We present a class solution for dose escalation in the pros

  4. 76 FR 20536 - Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing

    Science.gov (United States)

    2011-04-13

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 75 RIN 2060-AQ06 Protocol Gas Verification Program and Minimum Competency Requirements for Air Emission Testing Correction In rule document 2011-6216 appearing on pages 17288-17325 in...

  5. TRACEABILITY OF PRECISION MEASUREMENTS ON COORDINATE MEASURING MACHINES – PERFORMANCE VERIFICATION OF CMMs

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Sobiecki, René; Tosello, Guido

    This document is used in connection with one exercise of 30 minutes duration as a part of the course VISION ONLINE – One week course on Precision & Nanometrology. The exercise concerns performance verification of the volumetric measuring capability of a small volume coordinate measuring machine...

  6. A SURVEY ON VARIOUS APPROACHES TO FINGERPRINT MATCHING FOR PERSONAL VERIFICATION AND IDENTIFICATION

    OpenAIRE

    Dyre, Shoba; C.P.Sumathi

    2016-01-01

    Automatic Fingerprint authentication for personal identification and verification has received considerable attention over the past decades among various biometric techniques because of the distinctiveness and persistence properties of fingerprints. Now fingerprints are set to explode in popularity as they are being used to secure smart phones and to authorize payments in online stores. 

  7. Woodward Effect Experimental Verifications

    Science.gov (United States)

    March, Paul

    2004-02-01

    The work of J. F. Woodward (1990 1996a; 1996b; 1998; 2002a; 2002b; 2004) on the existence of ``mass fluctuations'' and their use in exotic propulsion schemes was examined for possible application in improving space flight propulsion and power generation. Woodward examined Einstein's General Relativity Theory (GRT) and assumed that if the strong Machian interpretation of GRT as well as gravitational / inertia like Wheeler-Feynman radiation reaction forces hold, then when an elementary particle is accelerated through a potential gradient, its rest mass should fluctuate around its mean value during its acceleration. Woodward also used GRT to clarify the precise experimental conditions necessary for observing and exploiting these mass fluctuations or ``Woodward effect'' (W-E). Later, in collaboration with his ex-graduate student T. Mahood, they also pushed the experimental verification boundaries of these proposals. If these purported mass fluctuations occur as Woodward claims, and his assumption that gravity and inertia are both byproducts of the same GRT based phenomenon per Mach's Principle is correct, then many innovative applications such as propellantless propulsion and gravitational exotic matter generators may be feasible. This paper examines the reality of mass fluctuations and the feasibility of using the W-E to design propellantless propulsion devices in the near to mid-term future. The latest experimental results, utilizing MHD-like force rectification systems, will also be presented.

  8. Necrólisis epidérmica tóxica: Descripción de 1 caso

    Directory of Open Access Journals (Sweden)

    Odalis Peña Pérez

    2001-12-01

    Full Text Available Se presenta un caso de necrólisis epidérmica tóxica, enfermedad poco frecuente y con alto índice de mortalidad, en un neonato a término, de madre primigesta, con tiempo de gestación de 39,2 semanas; parto eutócico y apgar 8/9, con un peso corporal de 3 770 que a las 2 horas del nacimiento comenzó con lesiones eritematoampollosas y centro necrótico, que rápidamente evolucionó de forma desfavorable y fallece a las 33 horas de nacido. Se realiza revisión bibliográfica del tema y se emiten comentarios de su probable patogenia.A case of toxic epidermal necrolysis, a rare disease with a high mortality rate, is presented in a term infant of a primigravida with 39.2 weeks of gestation, eutocic delivery, apgar 8/9, and a body weight of 3 770 g, that presented erythematous and ampollous lesions and necrotic center 2 hours after having been delivered and had a fast unfavorable evolution and died 33 hours after birth. A bibliographic review of the topic was made and its probable pathogeny was commented.

  9. Online Advertising

    OpenAIRE

    Goldfarb, Avi; Tucker, Catherine Elizabeth

    2011-01-01

    This chapter explores what makes online advertising different from traditional advertising channels. We argue that online advertising differs from traditional advertising channels in two important ways: measurability and targetability. Measurability is higher because the digital nature of online advertising means that responses to ads can be tracked relatively easily. Targetability is higher because data can be automatically tracked at an individual level, and it is relatively easy to show di...

  10. Meningite meningocócica: avaliação em período pré-epidêmico e epidêmico no Rio de Janeiro (1973-1975

    Directory of Open Access Journals (Sweden)

    Nélson Jerônimo Lourenço

    1975-10-01

    Full Text Available São relatadas observações acumuladas nos períodos pré-epidêmico e epidêmico (1973-1975 do atual surto de meningoencefalite meningocócica na área do Grande Rio, e realizados estudos bacteriológicos baseados em 1.000 casos suspeitos de meningoencefalite e submetidos à punção lombar, no Hospital Estadual São Sebastião. É proposto e discutido esquema simples e eficaz para processamento bacteriológico dos LCR suspeitos, a partir da colheita e pronta semeadura do material. É também discutida a real contribuição da bacterioscopia no diagnóstico presuntivo das meningoencefalites, definindo-se as limitações da técnica. Foi obtido elevado grau de isolamento de microorganismos, variando de 3%, para líquores entre zero e 10 células/mm' e 72%, para líquores acima de 1000 células/mm³. No decorrer do estudo, foram isoladas e caracterizadas 356 amostras bacterianas, assim discriminadas: N. meningitidis, 281; Haemophilus sp., 22; Enterobacteriaceae, 15; D. pneumoniae, 26; bastonetes gram negativos oxidattvos, 3; estreptococo beta hemolitico, 1 e enterococo, 1. As amostras de meningococos eram, em 15% dos casos, do grupo sorológico A, em 2% do grupo B e em 14%, do grupo sorológico C. Os testes de sensibilidade, em disco, aos agentes antimicrobianos principalmente utilizados na quimioprofilaxia e tratamento da doença meningocócica revelaram alto grau de sensibilidade das amostras ensaiadas a todos os agentes testados. A resistência à sulfadiazina sódica, em testes realizados segundo as normas preconizadas pela Food and Drug Administration (F.D.A., revelaram elevado grau de resistência, particularmente dos meningococos do grupo C.Data from the pre-epidemic period and from the present epidemic of meningococcal meningoencephalitis in the Great Rio de Janeiro area are presented. A thousand suspected cases were bacteriologically studied after lumbar spinal puncture at the Hospital Estadual São Sebastião, in Rio de Janeiro. Aiming

  11. Verification hybrid control of a wheeled mobile robot and manipulator

    Science.gov (United States)

    Muszynska, Magdalena; Burghardt, Andrzej; Kurc, Krzysztof; Szybicki, Dariusz

    2016-04-01

    In this article, innovative approaches to realization of the wheeled mobile robots and manipulator tracking are presented. Conceptions include application of the neural-fuzzy systems to compensation of the controlled system's nonlinearities in the tracking control task. Proposed control algorithms work on-line, contain structure, that adapt to the changeable work conditions of the controlled systems, and do not require the preliminary learning. The algorithm was verification on the real object which was a Scorbot - ER 4pc robotic manipulator and a Pioneer - 2DX mobile robot.

  12. Functional verification coverage measurement and analysis

    CERN Document Server

    Piziali, Andrew

    2007-01-01

    This book addresses a means of quantitatively assessing functional verification progress. Without this process, design and verification engineers, and management, are left guessing whether or not they have completed verifying the device they are designing.

  13. 10 CFR 300.11 - Independent verification.

    Science.gov (United States)

    2010-01-01

    ... skills required for verification are often cross-disciplinary. For example, an individual verifier...) Companies that provide verification services must use professionals that possess the necessary skills and...: American Institute of Certified Public Accountants; American National Standards Institute's...

  14. Biometric Technologies and Verification Systems

    CERN Document Server

    Vacca, John R

    2007-01-01

    Biometric Technologies and Verification Systems is organized into nine parts composed of 30 chapters, including an extensive glossary of biometric terms and acronyms. It discusses the current state-of-the-art in biometric verification/authentication, identification and system design principles. It also provides a step-by-step discussion of how biometrics works; how biometric data in human beings can be collected and analyzed in a number of ways; how biometrics are currently being used as a method of personal identification in which people are recognized by their own unique corporal or behavior

  15. SU-E-T-62: A Preliminary Experience of Using EPID Transit Dosimetry for Monitoring Daily Dose Variations in Radiation Treatment Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Yao, R; Chisela, W [Columbus Regional Healthcare, Columbus, GA (United States)

    2015-06-15

    Purpose: To investigate the use of EPID transit dosimetry for monitoring daily dose variations in radiation treatment delivery. Methods: A patient with head and neck cancer treated using nine field IMRT beams was used in this study. The prescription was 45 Gy in 25 fractions. A KV CBCT was acquired before each treatment on a Varian NTX linear accelerator. Integrated images using MV EPID were acquired for each treatment beam. Planning CT images, treatment plan, and daily integrated images were imported into a commercial QA software Dosimetry Check (v4r4 Math Resolutions, LLC, Columbia, MD) to calculate 3D dose of the day assuming 25 fractions treatment. Planning CT images were deformed and registered to each daily CBCT using Varian SmartAdapt (v11.MR2). ROIs were then propagated from planning CT to daily CBCT. The correlation between maximum, average dose of ROIs and ROI volume, center of mass shift, Dice Similarity Coefficient (DSC) were investigated. Results: Not all parameters investigated showed strong correlations. For PTV and CTV, the average dose has inverse correlation with their volume change (correlation coefficient −0.52, −0.50, respectively) and DSC (−0.59, −0.59, respectively). The average dose of right parotid has correlation with its volume change (0.56). The maximum dose of spinal cord has correlation with the center of mass superior-inferior shift (0.52) and inverse correlation with the center of mass anterior-posterior shift (−0.73). Conclusion: Transit dosimetry using EPID images collected during treatment delivery offers great potential to monitor daily dose variations due to patient anatomy change, motion, and setup errors in radiation treatment delivery. It can provide a patient-specific QA tool valuable for adaptive radiation therapy. Further work is needed to validate the technique.

  16. Análisis de un brote epidémico de brucelosis en trabajadores de un matadero

    Directory of Open Access Journals (Sweden)

    Luna Sánchez Antonio

    1998-01-01

    Full Text Available FUNDAMENTO: La notificación mediante el Sistema de Vigilancia Epidemiológica de un número inusual de casos de Brucelosis en trabajadores de un matadero a finales de 1996 hizo sospechar la existencia de un brote epidémico entre dicho colectivo profesional. MÉTODOS: Se recopiló la información disponible respecto a: 1 animales sacrificados en el matadero diagnosticados de brucelosis; 2 bajas laborales producidas y 3 datos de la mutualidad laboral relativos a los empleados del matadero con la enfermedad. Se realizó una encuesta epidemiológica a los trabajadores sobre los antecedentes de enfermedad, actividad laboral y riesgos no laborales (ingesta de leche o derivados sin higienizar. Las dependencias y actividades del matadero fueron inspeccionadas. Se diseñó un estudio de casos y controles. Se estudió cada puesto de trabajo tomando como controles a los restantes empleados del matadero. Para su verificación se realizó un estudio retrospectivo de cohortes. RESULTADOS: El brote epidémico de la enfermedad entre los trabajadores comenzó durante el mes de septiembre y duró hasta febrero del siguiente año. Las encuestas epidemiológicas descubrieron 28 trabajadores con síntomas sugestivos de la enfermedad, siendo los operarios del área de sacrificio del matadero quienes presentan la tasa de ataque más alta: 56%. En el estudio de casos y controles el riesgo más elevado se observó en dicho colectivo de trabajadores con una OR de 4,27 (IC 95%: 1,6-15 y p<0.01. Del mismo modo en el estudio de cohortes apreciamos que estos trabajadores presentan un RR de 2,5 (IC 95%: 1,5-4,3 cuando son comparados con el resto de trabajadores de la cohorte y de 8 (IC 95%: 2-30 si los comparamos con el colectivo de menor exposición. Los RR de los operarios de la limpieza y de la sala de despiece fueron de 6,56 (IC 95%: 1,6-27 para los primeros y de 4,77 (IC 95%: 1,1-21 para los segundos. Las fracciones etiológicas fueron del 87% para los de la zona de

  17. Factores de riesgo en la neuropatía epidémica periférica

    Directory of Open Access Journals (Sweden)

    Valentina Herrero Vicente

    2001-06-01

    Full Text Available Se realizó un estudio de casos y controles con el objetivo de profundizar en el conocimiento de factores de riesgo relacionados con la neuropatía epidémica periférica. El universo de estudio estuvo conformado por la totalidad de enfermos diagnosticados por la comisión provincial durante el período de 1993 a 1998, correspondiente al área de salud del policlínico "13 de Marzo", y los controles fueron escogidos en forma aleatoria con similares variables epidemiológicas. Se comprobó que no hubo asociación con la edad, y que el sexo femenino fue el más afectado. El incremento de la actividad física y el hábito de fumar tuvieron alta significación estadística. El alcoholismo resultó importante asociado al tabaquismo. Se concluyó que la actividad física intensa, la no ingestión de suplemento vitamínico y la nutrición deficitaria son factores de riesgo importantes en la aparición de la enfermedadA case-control study was performed to expand the knowledge on risk factors related to peripheral epidemic neuropathy. The universe of study was made up of all the patients diagnosed by the provincial commission from 1993 to 1998 in the health area of "13 de Marzo" polyclinics whereas the controls with similar epidemiological variables were randomly selected. It was proved that there was no association with age, and that females were the most affected. The increased physical activity and smoking had statistical significance. Alcoholism was found to be important associated with smoking. It was concluded that the internal physical activity, no ingestion of vitamin supplements and malnutrition are important risk factors in the occurrence of the disease

  18. Efficient online detection of temporal patterns

    Directory of Open Access Journals (Sweden)

    Shlomi Dolev

    2016-04-01

    Full Text Available Identifying a temporal pattern of events is a fundamental task of online (real-time verification. We present efficient schemes for online monitoring of events for identifying desired/undesired patterns of events. The schemes use preprocessing to ensure that the number of comparisons during run-time is minimized. In particular, the first comparison following the time point when an execution sub-sequence cannot be further extended to satisfy the temporal requirements halts the process that monitors the sub-sequence.

  19. Evaluación neuroquímica de la neuropatía óptica epidémica

    OpenAIRE

    González-Quevedo Monteagudo , Alina

    2004-01-01

    La aparición súbita en Cuba de una epidemia de neuropatía óptica en 1992,desencadenó una serie de investigaciones dirigidas a esclarecer las causas subyacentes. El presente trabajo investigó la participación del balance de aminoácidos sistémicos y en el sistema nervioso, la permeabilidad de la barrera hematoencefálica (BHE) y la neurotoxicidad del metanol en la fisiopatología de la neuropatía óptica epidémica (NOE). Se llevaron a cabo estudios en pacientes con NOE y en un modelo experimental ...

  20. Nevo epidérmico inflamatorio lineal (NEVIL): Presentación en la edad adulta Inflammatory linear verrucous epidermal nevus (ILVEN): Late onset disease

    OpenAIRE

    E J Carbó Amoroso; M G Díaz; M V Guardati; Reyes, M. A.; Weidmann, J.; E Henares; J L Iribas; J Blanck

    2008-01-01

    El NEVIL es la variedad inflamatoria del nevo epidérmico; es un tumor benigno hamartomatoso, que se distribuye siguiendo las líneas de Blaschko. Estas líneas representarían mosaicismos cutáneos del desarrollo embriológico. El NEVIL suele aparecer en la infancia. Son generalmente unilaterales y en ocasiones muy pruriginosos. El diagnóstico diferencial es frecuentemente dificultoso. Presentamos una paciente en la cual la manifestación de esta patología se produce en forma tardía, siendo esto po...

  1. Identificação histoquímica de carboidratos em epidídimo e funículoespermático humanos de pacientescom filariose

    OpenAIRE

    SILVA, Cynarha Daysy Cardoso da

    2006-01-01

    Para avaliar a eficiência da histoquímica com lectinas no mapeamento do perfil de carboidratos do sistema verme-granuloma e vasos sanguíneos em epidídimo e funículo espermático de pacientes infectados com Wuchereria bancrofti foram utilizadas lectinas conjugadas a peroxidase (Concanavalina A, Con A; lectina de germe de trigo, WGA; Lotus tetragonolobus agglutinin, LTA; peanut agglutinin, PNA; Ulex europeus I, UEA I). Os resultados demonstraram que as lectinas utilizadas reconheceram de forma d...

  2. Narrativa epidémica. La construcción social de las crisis sanitarias en la ficción literaria

    OpenAIRE

    Nespereira García, Javier

    2015-01-01

    Las crisis sanitarias de las últimas décadas han sido al mismo tiempo crisis mediáticas, históricas y socioculturales. En este contexto, numerosos autores han señalado la importancia de las narrativas de ficción en la transformación y transmisión de los valores morales e ideológicos implicados. En el siguiente trabajo presentamos el estudio comparativo de dos obras de ficción narrativa literaria en las que el relato se estructura en torno a la gestión de una crisis epidémica...

  3. Formal Verification of the Merchant Registration Phase of the SET Protocol

    Institute of Scientific and Technical Information of China (English)

    Xiao-Qi Ma; Xiao-Chun Cheng

    2005-01-01

    This paper describes the formal verification of the Merchant Registration phase of the Secure Electronic Transactions (SET) protocol, a realistic electronic transaction security protocol which is used to protect the secrecy of online purchases. A number of concepts, notations, functions, predicates, assumptions and rules are introduced. We describe the knowledge of all legal participants, and a malicious spy, to assess the security of the sub-protocol. Avoiding search in a large state space, the method converges very quickly. We implemented our method in the Isabelle/Isar automated reasoning environment, therefore the whole verification process can be executed mechanically and efficiently.

  4. Automated Verification of Virtualized Infrastructures

    DEFF Research Database (Denmark)

    Bleikertz, Sören; Gross, Thomas; Mödersheim, Sebastian Alexander

    2011-01-01

    Virtualized infrastructures and clouds present new challenges for security analysis and formal verification: they are complex environments that continuously change their shape, and that give rise to non-trivial security goals such as isolation and failure resilience requirements. We present a pla...

  5. Eggspectation : organic egg verification tool

    NARCIS (Netherlands)

    Ruth, van S.M.; Hoogenboom, L.A.P.

    2011-01-01

    In 2009 RIKILT conducted a study on about 2,000 eggs to evaluate three different analytical verification methods: carotenoid profiling, fatty acid profiling and isotope ratio mass spectrometry. The eggs were collected from about 50 Dutch farms. The selection was based on the farms’ location and size

  6. Online Tracking

    Science.gov (United States)

    ... Making Money Privacy, Identity & Online Security Blog Video & Media Scam Alerts ... Feed Facebook YouTube Twitter The Federal Trade Commission (FTC) is the nation’s consumer protection agency. ...

  7. Online dictionaries

    DEFF Research Database (Denmark)

    Tarp, Sven

    2012-01-01

    This article initially provides a panoramic overview and a preliminary typologization of present and future online dictionaries based upon their application of the available technologies and suggests that the future of lexicography will be the development of highly sophisticated tools which may......, need, consultation, and data. The article then proceeds to the discussion of some advanced information science techniques that may contribute to the desired individualization. Upon this basis, it finally discusses the interaction between online dictionaries and external sources like the Internet...

  8. Online marketing

    OpenAIRE

    Zrůst, Daniel

    2013-01-01

    The aim of this thesis is to evaluate pay per click marketing as suitable marketing tool for promotion and distribution of a given product. The paper describes basic vocabulary related to PPC advertising, common metrics, tools used by online marketers, and logic of running PPC campaigns. The paper also tries to quantify impact of Internet on economies. The second part applies the theory to analysis of consumers' conversion path while searching online in common search engines where PPC marketi...

  9. O Epidítico e(m cenas da enunciação: a amplificação do discurso organizacional em publicidades

    Directory of Open Access Journals (Sweden)

    André William Alves de Assis

    2015-07-01

    Full Text Available A partir da hipótese de que o discurso epidítico funciona em um quadro enunciativo-cenográfico, analisamos duas publicidades veiculadas na Revista Exame, em seu ‘Guia Exame de Sustentabilidade’, ancorados no escopo teórico da Análise do Discurso (MAINGUENEAU, 1997, 2006, 2008, 2011 e nos estudos da Argumentação (PERNOT, 1993; PERELMAN & OLBRECHTS-TYTECA, 2005; BRANDÃO, 2011; AMOSSY, 2011; entre outros. Observamos que o epidítico, em segundo plano, funciona como um amplificador daquilo que é apresentado pela empresa, como prática sustentável, dando maior evidência, no primeiro plano, à cenografia que vende a ideia e o produto das empresas, virtudes selecionadas e elogiadas pela revista. Essas virtudes estão relacionadas a uma ampla rede de práticas institucionais, tematizadas e especificadas na publicidade que vende um modelo de prática aos leitores.

  10. Diagnóstico temprano en un brote epidémico del virus Dengue en Piura usando RT-PCR y nested-PCR

    Directory of Open Access Journals (Sweden)

    Oscar Nolasco

    1997-07-01

    Full Text Available Un test de diagnóstico temprano (RT-PCR y Nested-PCR fue evaluado y comparado con métodos convencionales (cultivo in vitro, IFI y MAC-ELISA. Treinta y cuatro sueros de pacientes correspondientes de un brote epidémico de la costa norte peruana (Mancora, Piura en mayo de 1997 fueron incluidos en este estudio. Todos los sueros fueron obtenidos de pacientes que presentaron en los primeros cinco días manifestaciones clínicas siendo diagnosticados luego como dengue serotipo 1. Asimismo, RT-PCR permitió diagnosticar 82% de los sueros (28/34, sin embargo Mac-ELISA y cultivo in vitro reconocieron unicamente 41% de los sueros (14/34 y 38% de los sueros (13/34 respectivamente. Por lo tanto, el uso de esta herramienta molecular (RT-PCR y Nested-PCR permitiró dar un diagnóstico temprano a estos pacientes y actuar inmediatamente ante la presencia de un brote epidémico.

  11. Formal Verification of Continuous Systems

    DEFF Research Database (Denmark)

    Sloth, Christoffer

    2012-01-01

    and the verification procedures should be algorithmically synthesizable. Autonomous control plays an important role in many safety-critical systems. This implies that a malfunction in the control system can have catastrophic consequences, e.g., in space applications where a design flaw can result in large economic...... losses. Furthermore, a malfunction in the control system of a surgical robot may cause death of patients. The previous examples involve complex systems that are required to operate according to complex specifications. The systems cannot be formally verified by modern verification techniques, due......The purpose of this thesis is to develop a method for verifying timed temporal properties of continuous dynamical systems, and to develop a method for verifying the safety of an interconnection of continuous systems. The methods must be scalable in the number of continuous variables...

  12. Program Verification of Numerical Computation

    OpenAIRE

    Pantelis, Garry

    2014-01-01

    These notes outline a formal method for program verification of numerical computation. It forms the basis of the software package VPC in its initial phase of development. Much of the style of presentation is in the form of notes that outline the definitions and rules upon which VPC is based. The initial motivation of this project was to address some practical issues of computation, especially of numerically intensive programs that are commonplace in computer models. The project evolved into a...

  13. Kleene Algebra and Bytecode Verification

    Science.gov (United States)

    2016-04-27

    Bytecode 2005 Preliminary Version Kleene Algebra and Bytecode Verification Lucja Kot 1 Dexter Kozen 2 Department of Computer Science Cornell...first-order methods that inductively annotate program points with abstract values. In [6] we introduced a second-order approach based on Kleene algebra ...form a left-handed Kleene algebra . The dataflow labeling is not achieved by inductively labeling the program with abstract values, but rather by

  14. Content analysis of age verification, purchase and delivery methods of internet e-cigarette vendors, 2013 and 2014.

    Science.gov (United States)

    Williams, Rebecca S; Derrick, Jason; Liebman, Aliza Kate; LaFleur, Kevin; Ribisl, Kurt M

    2017-05-08

    Identify the population of internet e-cigarette vendors (IEVs) and conduct content analyses of their age verification, purchase and delivery methods in 2013 and 2014. We used multiple sources to identify IEV websites, primarily complex search algorithms scanning more than 180 million websites. In 2013, we manually screened 32 446 websites, identifying 980 IEVs, selecting the 281 most popular for content analysis. This methodology yielded 31 239 websites for screening in 2014, identifying 3096 IEVs, with 283 selected for content analysis. The proportion of vendors that sold online-only, with no retail store, dropped significantly from 2013 (74.7%) to 2014 (64.3%) (p<0.01), with a corresponding significant decrease in US-based vendors (71.9% in 2013 and 65% in 2014). Most vendors did little to prevent youth access in either year, with 67.6% in 2013 and 63.2% in 2014 employing no age verification or relying exclusively on strategies that cannot effectively verify age. Effective age verification strategies such as online age verification services (7.1% in 2013 and 8.5% in 2014), driving licences (1.8% in 2013 and 7.4% in 2014, p<0.01) or age verification at delivery (6.4% in 2013 and 8.1% in 2104) were rarely advertised on IEV websites. Nearly all vendors advertised accepting credit cards, and about ¾ shipping via United States Postal Service, similar to the internet cigarette industry prior to federal bans. The number of IEVs grew sharply from 2013 to 2014, with poor age verification practices. New and expanded regulations for online e-cigarette sales are needed, including strict age and identity verification requirements. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  15. Out Online

    DEFF Research Database (Denmark)

    Raun, Tobias

    Trans people are increasingly stepping out of the shadow of pathologization and secretiveness to tell their life stories, share information and to connect with like-minded others, using YouTube as a platform. "Out Online: Trans Self-Representation and Community Building on YouTube" explores...... on the ways in which the video blog (or ’vlog’) as a multimodal medium enables trans people to tell their stories with the use of sound, text, music, and pictures - thus offering new ways to construct and archive bodily changes, and to revise the story endlessly. A groundbreaking study of the intersection...... between trans identity and technology, "Out Online" explores the transformative and therapeutic potential of the video blog as a means by which trans vloggers can emerge and develop online, using the vlog as a site for creation, intervention, community building and resistance. As such, it will appeal...

  16. Online Innovation

    DEFF Research Database (Denmark)

    Vujovic, Sladjana; Ulhøi, John Parm

    2008-01-01

    ways of communicating, cooperating and coordinating during the innovation and product development process. Moreover, it challenges the traditional business model in that it forces the actors involved to shift the focus from the innovation itself to the identification of new supporting services higher...... implications for existing software manufacturers. The paper therefore includes the case of IBM, a company which has successfully integrated this new and more open way of collaboration into its business model. Findings - The paper concludes that online computer-based innovation fundamentally challenges current......  Purpose - The aim of this paper is to investigate the role of online networking during the innovation process, including its role(s) in communication, cooperation and coordination. The paper neither implicitly assumes that online computer-based networking is a prerequisite for the innovation...

  17. Nuclear Data Verification and Standardization

    Energy Technology Data Exchange (ETDEWEB)

    Karam, Lisa R.; Arif, Muhammad; Thompson, Alan K.

    2011-10-01

    The objective of this interagency program is to provide accurate neutron interaction verification and standardization data for the U.S. Department of Energy Division of Nuclear Physics programs which include astrophysics, radioactive beam studies, and heavy-ion reactions. The measurements made in this program are also useful to other programs that indirectly use the unique properties of the neutron for diagnostic and analytical purposes. These include homeland security, personnel health and safety, nuclear waste disposal, treaty verification, national defense, and nuclear based energy production. The work includes the verification of reference standard cross sections and related neutron data employing the unique facilities and capabilities at NIST and other laboratories as required; leadership and participation in international intercomparisons and collaborations; and the preservation of standard reference deposits. An essential element of the program is critical evaluation of neutron interaction data standards including international coordinations. Data testing of critical data for important applications is included. The program is jointly supported by the Department of Energy and the National Institute of Standards and Technology.

  18. Regression Verification Using Impact Summaries

    Science.gov (United States)

    Backes, John; Person, Suzette J.; Rungta, Neha; Thachuk, Oksana

    2013-01-01

    Regression verification techniques are used to prove equivalence of syntactically similar programs. Checking equivalence of large programs, however, can be computationally expensive. Existing regression verification techniques rely on abstraction and decomposition techniques to reduce the computational effort of checking equivalence of the entire program. These techniques are sound but not complete. In this work, we propose a novel approach to improve scalability of regression verification by classifying the program behaviors generated during symbolic execution as either impacted or unimpacted. Our technique uses a combination of static analysis and symbolic execution to generate summaries of impacted program behaviors. The impact summaries are then checked for equivalence using an o-the-shelf decision procedure. We prove that our approach is both sound and complete for sequential programs, with respect to the depth bound of symbolic execution. Our evaluation on a set of sequential C artifacts shows that reducing the size of the summaries can help reduce the cost of software equivalence checking. Various reduction, abstraction, and compositional techniques have been developed to help scale software verification techniques to industrial-sized systems. Although such techniques have greatly increased the size and complexity of systems that can be checked, analysis of large software systems remains costly. Regression analysis techniques, e.g., regression testing [16], regression model checking [22], and regression verification [19], restrict the scope of the analysis by leveraging the differences between program versions. These techniques are based on the idea that if code is checked early in development, then subsequent versions can be checked against a prior (checked) version, leveraging the results of the previous analysis to reduce analysis cost of the current version. Regression verification addresses the problem of proving equivalence of closely related program

  19. Daily quality control of collimator multi-leaf for IMRT static through flat panel (EPID); Control de calidad diario del colimador multilamina para IMRT estatica mediante panel plano (EPID)

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Barrado, A.; Benitez Serrano, J. A.; Sanchez Jimenez, E.; Sanchez-Reyes, A.

    2013-07-01

    When techniques are employed such as radiotherapy for intensity modulated (IMRT) is necessary to establish a proper quality assurance program. According to national and international recommendations, such a program must include, in addition to verification of treatment for each patient, a multi-leaf collimator quality control daily, easy to perform and analyze, to ensure the quality of the given treatments daily. This paper intends to make such quality control through the irradiation of a number of fields in the imaging system flat panel portal and its subsequent analysis. (Author)

  20. Online safety

    CERN Document Server

    Healey, Justin

    2015-01-01

    Australians are increasingly connecting online through computers, mobile phones and other electronic devices to access the internet and social media. In the process, young people in particular are becoming more at risk of being exposed to fraud, identity theft, unauthorised access to personal information, stalking, harassment and exposure to illicit or offensive materials. This book presents a range of cybersafety tips to arm readers with an informed awareness of the risks online and offer advice on how to stay protected. A chapter in the book is specifically dedicated to understanding and dea

  1. Online Communities

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Lassen, Astrid Heidemann; Gorm Hansen, Katrine

    Online Communities” er et medie for brugere og fagfolk, hvor de kan mødes digitalt for at dele erfaringer, og dette kan anvendes som inspiration indenfor Brugerdreven Innovation. Via ”desk research” kan virksomheder opnå adgang til varierende mængder af brugere på en forholdsvist enkelt måde. I...... denne rapport beskrives eksperimentets opbygning, resultater og mulige værdi. Vi håber hermed på at kunne give praktisk indsigt i, hvorledes virksomheder fra byggematerialeindustrien kan agere i online communities....

  2. Fingerprint verification based on wavelet subbands

    Science.gov (United States)

    Huang, Ke; Aviyente, Selin

    2004-08-01

    Fingerprint verification has been deployed in a variety of security applications. Traditional minutiae detection based verification algorithms do not utilize the rich discriminatory texture structure of fingerprint images. Furthermore, minutiae detection requires substantial improvement of image quality and is thus error-prone. In this paper, we propose an algorithm for fingerprint verification using the statistics of subbands from wavelet analysis. One important feature for each frequency subband is the distribution of the wavelet coefficients, which can be modeled with a Generalized Gaussian Density (GGD) function. A fingerprint verification algorithm that combines the GGD parameters from different subbands is proposed to match two fingerprints. The verification algorithm in this paper is tested on a set of 1,200 fingerprint images. Experimental results indicate that wavelet analysis provides useful features for the task of fingerprint verification.

  3. Consent Based Verification System (CBSV)

    Data.gov (United States)

    Social Security Administration — CBSV is a fee-based service offered by SSA's Business Services Online (BSO). It is used by private companies to verify the SSNs of their customers and clients that...

  4. Online 1990.

    Science.gov (United States)

    Goldstein, Morris

    This paper examines the co-existence of online and CD-ROM technologies in terms of their existing pricing structures, marketing strategies, functionality, and future roles. "Fixed Price Unlimited Usage" (FPUU) pricing and flat-rate pricing are discussed as viable alternatives to current pricing practices. In addition, it is argued that the…

  5. Online dictionaries

    DEFF Research Database (Denmark)

    Tarp, Sven

    2012-01-01

    , need, consultation, and data. The article then proceeds to the discussion of some advanced information science techniques that may contribute to the desired individualization. Upon this basis, it finally discusses the interaction between online dictionaries and external sources like the Internet...

  6. A SURVEY ON VARIOUS APPROACHES TO FINGERPRINT MATCHING FOR PERSONAL VERIFICATION AND IDENTIFICATION

    OpenAIRE

    Shoba Dyre; C.P.Sumathi

    2016-01-01

    Automatic Fingerprint authentication for personal identification and verification has received considerable attention over the past decades among various biometric techniques because of the distinctiveness and persistence properties of fingerprints. Now fingerprints are set to explode in popularity as they are being used to secure smart phones and to authorize payments in online stores. The main objective of this paper is to review the extensive research work that has been done over the pa...

  7. Estimating output fluence with MCNP4 for shaped fields and their comparison with measurements in the EPID system aS1000 for dosimetry 2D in-vivo; Estimacion de la fluencia de salida con MCNP4 para campos conformados y su comparacion con mediciones en el sistema EPID aS1000 para dosimetria in-vivo 2D

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez R, B.; Rodriguez P, X.; Sosa, M., E-mail: bhernandez@fisica.ugto.mx [Universidad de Guanajuato, Division de Ciencias e Ingenierias, Loma del Bosque No. 103, 37150 Leon, Guanajuato (Mexico)

    2015-10-15

    Full text: Radiotherapy dosimetry is a fundamental process in quality control of the treatments performed with this technique. Different systems exist to quantify radiation dose in radiotherapy, one of them is the Electronic Portal Imaging Device (EPID), which is widely used in IMRT to measure the output fluence of a radiation field for comparison with a predicted fluence in a planning system. The objective of this work was to simulate a Varian linear accelerator model Clinac i X using the MCNP4 code for obtaining curves of percentage depth dose (Pdd) and open fields dosimetric profiles of 5 x 5, 10 x 10, 20 x 20 and 30 x 30 cm{sup 2}. The simulations were validated by comparing them with measurements made with ionization chamber. Then a mannequin of solid water (30 x 30 x 20 cm{sup 3}) with an open field of 10 x 10 cm{sup 2} was irradiated to measure the output fluence with EPID aS1000 system of Varian. A simulation of the solid water mannequin under the same conditions of irradiation was conducted to estimate the output fluence. Tests of index gamma and percentage differences were calculated to compare that simulated with that measured. In all cases was found that more than 95% of the evaluated points passed the acceptance criteria (ΔD= 1% and ΔS= 1 mm for curves Pdd and profiles, and ΔD= 3% and ΔS= 3 mm for fluence two-dimensional). This paper will contribute to the implementation of in-vivo dosimetry three-dimensional with the EPID system. (Author)

  8. Craniocaudal safety margin calculation based on interfractional changes in tumor motion in lung SBRT assessed with an EPID in cine mode.

    Science.gov (United States)

    Ueda, Yoshihiro; Miyazaki, Masayoshi; Nishiyama, Kinji; Suzuki, Osamu; Tsujii, Katsutomo; Miyagi, Ken

    2012-07-01

    To evaluate setup error and interfractional changes in tumor motion magnitude using an electric portal imaging device in cine mode (EPID cine) during the course of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC) and to calculate margins to compensate for these variations. Subjects were 28 patients with Stage I NSCLC who underwent SBRT. Respiratory-correlated four-dimensional computed tomography (4D-CT) at simulation was binned into 10 respiratory phases, which provided average intensity projection CT data sets (AIP). On 4D-CT, peak-to-peak motion of the tumor (M-4DCT) in the craniocaudal direction was assessed and the tumor center (mean tumor position [MTP]) of the AIP (MTP-4DCT) was determined. At treatment, the tumor on cone beam CT was registered to that on AIP for patient setup. During three sessions of irradiation, peak-to-peak motion of the tumor (M-cine) and the mean tumor position (MTP-cine) were obtained using EPID cine and in-house software. Based on changes in tumor motion magnitude (∆M) and patient setup error (∆MTP), defined as differences between M-4DCT and M-cine and between MTP-4DCT and MTP-cine, a margin to compensate for these variations was calculated with Stroom's formula. The means (±standard deviation: SD) of M-4DCT and M-cine were 3.1 (±3.4) and 4.0 (±3.6) mm, respectively. The means (±SD) of ∆M and ∆MTP were 0.9 (±1.3) and 0.2 (±2.4) mm, respectively. Internal target volume-planning target volume (ITV-PTV) margins to compensate for ∆M, ∆MTP, and both combined were 3.7, 5.2, and 6.4 mm, respectively. EPID cine is a useful modality for assessing interfractional variations of tumor motion. The ITV-PTV margins to compensate for these variations can be calculated. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. SU-E-J-24: An Evaluation of the Stability of Image Quality Parameters of Varian On-Board Imaging (OBI) and EPID Imaging Systems

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, D; Papanikolaou, N; Gutierrez, A [University of Texas HSC SA, San Antonio, TX (United States)

    2014-06-01

    Purpose: Quality assurance of the image quality for image guided localization systems is crucial to ensure accurate visualization and localization of target volumes. In this study, the long term stability of selected image parameters was assessed and evaluated for CBCT mode, planar radiographic kV mode and the radiographic MV EPID mode. Methods: The CATPHAN, QckV-1 and QC-3 phantoms were used to evaluate the image quality parameters. The planar radiographic images were analyzed in PIPSpro™ with spatial resolution (f30, f40, f50) being recorded. For OBI CBCT, High quality head Full-Fan acquisition and Pelvis Half-Fan acquisition modes were evaluated for Uniformity, Noise, Spatial Resolution, HU constancy and geometric distortion. Dose and kVp for the OBI were recorded using the Unfors RaySafe Xi system with the R/F High Detector for planar kV and the CT detector for CBCT. Dose for the MV EPID was recorded using a PTW975 Semiflex Ion Chamber, PTW Unidos electrometer and SolidWater™. Results: For each metric, values were normalized to the mean and the standard deviations were recorded. For the planar radiographic spatial resolution the f30, f40, f50 were 0.015, 0.008, 0.004 and 0.006, 0.009, 0.018 for the kV and MV, respectively. The standard deviation of the dose for kV was 0.010 and 0.005 for the MV. The standard deviations for Full and half fan were averaged together and the following standard deviations for each metric were recorded: 0.075(uniformity), 0.071(noise), 0.006(AP-Geometric Distortion), 0.005(LAT-Geometric Distortion), 0.058(mean slice thickness), 0.098(f30),0.101(f40),0.124(f50), 0.031(Lung/PMP-HU constancy), 0.063(Water/poly-HU constancy), 0.015(Bone/Derlin-HU constancy),0.006(Dose-Center), 0.004(Dose-Periphery). Using these, tolerances can be reported as a warning and action threshold of 1σ and 2σ. Conclusion: A study was performed to assess the stability of the basic image quality parameters recommended by TG-142 for the Varian OBI and EPID

  10. Hiperplasia de Músculo Liso no Epidídimo: Revisão de Literatura/Smooth Muscle Hyperplasia of the Epididymis: A Literature Review

    Directory of Open Access Journals (Sweden)

    Ana Cecília Vieira Lisboa

    2014-12-01

    Full Text Available O epidídimo pode ser acometido por hiperplasia ou neoplasia, benigna ou maligna, sempre diferenciadas pelo estudo histopatológico. Ele tem como função coletar, amadurecer e armazenar espermatozóides constantemente produzidos pelos túbulos seminíferos. Patologias do epidídimo acometem homens na puberdade, o que pode resultar em alterações na maturação dos espermatozóides e até mesmo levar a infertilidade. A conduta dessa afecção é cirúrgica e pode ser desde ressecção da tumoração preservando-se estruturas hígidas como, por exemplo, os testículos, em casos benignos, até exploração peritoneal para esvaziamento linfonodal mais orquiectomia, em casos malignos. O objetivo foi realizar uma revisão de literatura sobre hiperplasia do epidídimo que auxilie no diagnóstico e tratamento precoces que diminuam a mortalidade, morbidade e sequelas dos pacientes. Como a patologia em questão tem baixa incidência, com predomínio de casos benignos e evolução sem complicações, conclui-se que há a necessidade de mais análises sobre o tema para melhor elucidar seu tratamento e, principalmente, as consequências. The epididymis may be affected by hyperplasia or neoplastic cells, always differentiated by histopathological study. It has the function of collecting, maturing and storing sperm that are constantly produced by the seminiferous tubules. Pathologies of epididymis affect male puberty, which may result in changes in the maturation of sperm and even lead to infertility. The conduct in this condition can be from a tumor resection preserving healthy structures such as, for example, the testicles, in benign cases, while in malignant cases chooses whether the peritoneal exploration for a lymph node dissection plus orchiectomy. The purpose was to conduct a literature review of hyperplasia of the epididymis that helps in the diagnosis and early treatment, which can lead to lower risk of mortality and morbidity allowing a decrease in

  11. Generating citizen trust in e-government using a trust verification agent: A research note

    OpenAIRE

    Elliman, T

    2006-01-01

    Generating Citizen Trust in e-Government using a Trust Verification Agent This is an eGISE network paper. It is motivated by a concern about the extent to which trust issues inhibit a citizen’s take-up of online public sector services or engagement with public decision and policy making. A citizen’s decision to use online systems is influenced by their willingness to trust the environment and agency involved. This project addresses one aspect of individual “trust” decisions by provid...

  12. Generating citizen trust in e-government using a trust verification agent: A research note

    OpenAIRE

    Tassabehji, Rana; Elliman, Tony

    2006-01-01

    Generating Citizen Trust in e-Government using a Trust Verification Agent This is an eGISE network paper. It is motivated by a concern about the extent to which trust issues inhibit a citizen’s take-up of online public sector services or engagement with public decision and policy making. A citizen’s decision to use online systems is influenced by their willingness to trust the environment and agency involved. This project addresses one aspect of individual “trust” decisions by providing...

  13. Implementation and validation of a commercial portal dosimetry software for intensity-modulated radiation therapy pre-treatment verification

    Directory of Open Access Journals (Sweden)

    Varatharaj C

    2010-01-01

    Full Text Available Electronic portal imaging devices (EPIDs are extensively used for obtaining dosimetric information of pre-treatment field verification and in-vivo dosimetry for intensity-modulated radiotherapy (IMRT. In the present study, we have implemented the newly developed portal dosimetry software using independent dose prediction algorithm EPIDose TM and evaluated this new tool for the pre-treatment IMRT plan quality assurance of Whole Pelvis with Simultaneous Integrated Boost (WP-SIB-IMRT of prostate cases by comparing with routine two-dimensional (2D array detector system (MapCHECK TM . We have investigated 104 split fields using g-distributions in terms of predefined g frequency parameters. The mean γ values are found to be 0.42 (SD: 0.06 and 0.44 (SD: 0.06 for the EPIDose and MapCHECK TM , respectively. The average g∆ for EPIDose and MapCHECK TM are found as 0.51 (SD: 0.06 and 0.53 (SD: 0.07, respectively. Furthermore, the percentage of points with g < 1, γ < 1.5, and γ > 2 are 97.4%, 99.3%, and 0.56%, respectively for EPIDose and 96.4%, 99.0% and 0.62% for MapCHECK TM . Based on our results obtained with EPIDose and strong agreement with MapCHECK TM , we may conclude that the EPIDose portal dosimetry system has been successfully implemented and validated with our routine 2D array detector

  14. Automated verification of flight software. User's manual

    Science.gov (United States)

    Saib, S. H.

    1982-01-01

    (Automated Verification of Flight Software), a collection of tools for analyzing source programs written in FORTRAN and AED is documented. The quality and the reliability of flight software are improved by: (1) indented listings of source programs, (2) static analysis to detect inconsistencies in the use of variables and parameters, (3) automated documentation, (4) instrumentation of source code, (5) retesting guidance, (6) analysis of assertions, (7) symbolic execution, (8) generation of verification conditions, and (9) simplification of verification conditions. Use of AVFS in the verification of flight software is described.

  15. Wind-farm power performance verification

    Energy Technology Data Exchange (ETDEWEB)

    Dutilleux, P. [DEWI German Wind Energy Institute, Wilhelmshaven (Germany)

    2005-07-01

    Details of wind farm power performance verification procedures were presented. Verifications were performed at the DEWI test site at Wilhelmhaven, Germany. Types of power performance guarantees included power performance of individual turbines with IEC verification measurement, and Nacelle anemometer verification. In addition, availability guarantees were examined, as well as issues concerning energy production guarantees of complete wind farms in relation to nearby meteorology masts. An evaluation of power curve verification measurements was presented as well as measurement procedures relating to IEC standards. Methods for Nacelle anemometry verification included calibration of the anemometer; documentation of its exact position and chain signal; and end-to-end calibration from sensor to SCADA data base. Classification of anemometers included impact of dynamical effects; and influence on annual energy production. An example of a project for performance verification of a wind farm with 9 identical wind turbines was presented. The significance of status signals was discussed, as well as alternative methods for power-curve measurements. Evaluation procedures for energy yield and power curve verifications were presented. The upcoming set of IEC standards concerning power curve measurements was discussed. Various alternative verification procedures for wind farm power performance were reviewed. refs., tabs., figs.

  16. The SeaHorn Verification Framework

    Science.gov (United States)

    Gurfinkel, Arie; Kahsai, Temesghen; Komuravelli, Anvesh; Navas, Jorge A.

    2015-01-01

    In this paper, we present SeaHorn, a software verification framework. The key distinguishing feature of SeaHorn is its modular design that separates the concerns of the syntax of the programming language, its operational semantics, and the verification semantics. SeaHorn encompasses several novelties: it (a) encodes verification conditions using an efficient yet precise inter-procedural technique, (b) provides flexibility in the verification semantics to allow different levels of precision, (c) leverages the state-of-the-art in software model checking and abstract interpretation for verification, and (d) uses Horn-clauses as an intermediate language to represent verification conditions which simplifies interfacing with multiple verification tools based on Horn-clauses. SeaHorn provides users with a powerful verification tool and researchers with an extensible and customizable framework for experimenting with new software verification techniques. The effectiveness and scalability of SeaHorn are demonstrated by an extensive experimental evaluation using benchmarks from SV-COMP 2015 and real avionics code.

  17. Availability of prescription drugs for bipolar disorder at online pharmacies.

    Science.gov (United States)

    Monteith, Scott; Glenn, Tasha; Bauer, Rita; Conell, Jörn; Bauer, Michael

    2016-03-15

    There is increasing use of online pharmacies to purchase prescription drugs. While some online pharmacies are legitimate and safe, there are many unsafe and illegal so-called "rogue" online pharmacies. This study investigated the availability of psychotropic drugs online to consumers in the US, using 5 commonly prescribed drugs for bipolar disorder. Using the search term "buy [drug name]" in the Google, Yahoo and Bing search engines, the characteristics of the online pharmacies found on the first two pages of search results were investigated. The availability of the requested dosage and formulations of two brand (Seroquel XR, Abilify) and three generic drugs (lamotrigine, lithium carbonate and bupropion SR) were determined. Of 30 online pharmacies found, 17 (57%) were rated as rogue by LegitScript. Of the 30 pharmacies, 15 (50%) require a prescription, 21 (70%) claim to be from Canada, with 20 of these having a Canadian International Pharmacy association (CIPA) seal on the website. Only 13 of the 20 sites with a CIPA seal were active CIPA members. There were about the same number of trust verification seals on the rogue and legitimate pharmacy sites. Some rogue pharmacies are professional in appearance, and may be difficult for consumers to recognize as rogue. All five brand and generic drugs were offered for sale online, with or without a prescription. However, many substitutions were presented such as different strengths and formulations including products not approved by the FDA. No evaluation of product quality, packaging or purchasing. Psychotropic medications are available online with or without a prescription. The majority of online pharmacy websites were rogue. Physicians should ask about the use of online pharmacies. For those who choose to use online pharmacies, two measures to detect rogue pharmacies are recommended: (1) only purchase drugs from pharmacies that require a prescription, and (2) check all pharmacy verification seals directly on the website

  18. The Global Diffusion of Societal Verification Tools: A Quantitative Assessment of the Public’s Ability to Engage Nonproliferation Treaty Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sayre, Amanda M.; Kreyling, Sean J.; West, Curtis L.

    2015-07-11

    The spread of nuclear and dual-use technologies and the need for more robust, effective and efficient nonproliferation and arms control treaties has led to an increasing need for innovative verification approaches and technologies. This need, paired with advancements in online computing, mobile devices, commercially available satellite imagery and the evolution of online social networks, has led to a resurgence of the concept of societal verification for arms control and nonproliferation treaties. In the event a country accepts its citizens’ assistance in supporting transparency, confidence-building and societal verification, the host government will need a population that is willing and able to participate. While scholarly interest in societal verification continues to grow, social scientific research on the topic is lacking. The aim of this paper is to begin the process of understanding public societal verification capabilities, extend the availability of quantitative research on societal verification and set in motion complementary research to increase the breadth and depth of knowledge on this topic. This paper presents a potential framework and outlines a research roadmap for the development of such a societal verification capability index.

  19. Qualität in der Online-Erziehungsberatung: Kriterien für eine Antwortmail

    Directory of Open Access Journals (Sweden)

    Petra Mayer

    2013-04-01

    Full Text Available Both the establishment of the theoretical fundamentals and the empirical verification could not keep pace with the rapid development in internet counseling. For quality assurance, however, such fundamentals and their empirical revisability and verification are indispensable. The examination, description and structuring of online educational counseling are an important step towards qualityassurance. Such information can help to support counselors in their practical work, and they can be used for educating counselors.

  20. Dengue: inquérito sorológico pós-epidêmico em zona urbana do Estado de São Paulo (Brasil)

    OpenAIRE

    Lima,Virgília L. C. de; Luiz T.M. Figueiredo; Heleno R Correa F; Odair F Leite; Osias Rangel; Alessandra A Vido; Susely S Oliveira; Miyoco A Owa; Rita H Carlucci

    1999-01-01

    OBJETIVO: Avaliar o tamanho real da epidemia sobre dengue ocorrida na zona urbana do Município de Santa Bárbara D'Oeste, SP, Brasil, de abril a junho de 1995. MÉTODOS: Foi realizado um inquérito soroepidemiológico pós-epidêmico 5 meses após o final da epidemia da dengue. Foram processados 1.113 soros através de amostragem aleatória domiciliar da população da cidade pesquisada. As taxas de infecção em diferentes partes da cidade foram relacionadas com os graus de infestação por Aedes aegipty e...

  1. Nevo epidérmico manifestando-se como hiperceratose do mamilo e aréola Verrucous epidermal nevus manifesting as nipple and areola hyperkeratosis

    Directory of Open Access Journals (Sweden)

    Roberto Rheingantz da Cunha Filho

    2006-08-01

    Full Text Available Relata-se caso raro de nevo epidérmico na aréola mamária direita de menina de 13 anos. Segundo a classificação proposta por Levy-Franckel, essa variante é a hiperceratose do mamilo e aréola do tipo I, quando associada a nevo verrucoso. A histologia mostrou papilomatose, acantose e hiperceratose. Foram realizadas duas sessões de crioterapia sem melhora. Foi obtido bom resultado por meio de shaving e eletrocauterização.A rare case of a 13-year-old female patient with epidermal verrucous nevus on the right areola is reported. According to the Levy-Franckel classification, this variant is a type I nipple and areola hyperkeratosis, when associated to verrucous nevus. Histopathological examination showed papillomatosis, acanthosis and hyperkeratosis. Cryotherapy yielded unsatisfactory results after two sessions. A good result was obtained with shaving and electrocauterization.

  2. [Disseminated Mycobacterium avium complex infections in AIDS. Apropos of 100 cases. Groupe d'Epidémiologie clinique du SIDA en Aquitaine].

    Science.gov (United States)

    Lasseur, C; Maugein, J; Pellegrin, J L; Dupon, M; Ragnaud, J M; Morlat, P; Pellegrin, I; Constans, J; Monlun, E; Chene, G

    1995-01-01

    The improvement of survival of AIDS patients allowed the emergence of disseminated Mycobacterium avium Complex infections (D.MAC). Here we report the experience of the group of "Epidémiologie clinique du sida en Aquitaine (GECSA)" about 100 patients. There were no differences according to sex, age and route of acquisition of HIV. Clinical and biological characteristics of the infections were not specific. The mean TCD4+ lymphocytes count was 18/mm3. The diagnostic was generally established by systematic blood culture on Septi-Chek in patients with TCD4+ lymphocytes count below 75/mm3. The recommendations on therapy for D.MAC are to use regimen containing azithromycin or clarithromycin, ethambutol and one of the following drugs, rifabutin, clofazimine, amikacin, or ciprofloxacin. Rifabutin is recommended for prophylaxis in patients with lymphocytes TCD4+ count below 100/mm3.

  3. Prevalencia y factores asociados al virus de la Diarrea Epidémica Porcina (PEDv) en transporte de cerdos a plantas de beneficio en Colombia

    OpenAIRE

    Pineda Otiz, María del Pilar; Corrales Morales, Johanna Paola

    2017-01-01

    Introducción: La diarrea epidémica porcina es una enfermedad infecciosa, que ataca principalmente a los lechones neonatos, con morbilidad del 80 al 100% y mortalidad del 50 al 90%. La forma más rápida de propagación del virus (PEDv) es el transporte de porcinos. Esta enfermedad ingresó a Colombia en el 2014 afectando la producción nacional sin que se conociera el comportamiento epidemiológico en el país. Previamente se había reportado a nivel mundial que la forma más rápida de propagación del...

  4. Papel del factor de crecimiento epidérmico recombinante humano “Heberprot-P” en un paciente con Lepra Multibacilar

    Directory of Open Access Journals (Sweden)

    Wilver Velázquez Chacón

    2014-08-01

    Full Text Available Se presenta el caso de un paciente masculino de 59 años de edad, tratado por vías convencionales a causa de lesiones ulcerativas de miembros inferiores, de más de siete años de evolución, sin diagnóstico y tratamiento. La evolución ulterior permitió reconocer la aparición subsecuente de lepra multibacilar. La basiloscopía fue positiva, indicando el diagnóstico de las lesiones ulcerativas, que se trataron con el uso de factor de crecimiento epidérmico recombinante humano en su formulación Heberprot-P, permitiendo la granulación de las lesiones en toda su extensión en un plazo corto, de 16 días, sin que se presentaran eventos adversos graves. Su resultado final fue satisfactorio

  5. Formal Verification of UML Profil

    DEFF Research Database (Denmark)

    Bhutto, Arifa; Hussain, Dil Muhammad Akbar

    2011-01-01

    The Unified Modeling Language (UML) is based on the Model Driven Development (MDD) approach which capturing the system functionality using the platform-independent model (PMI) and appropriate domain-specific languages. In UML base system notations, structural view is model by the class, components...... and object diagrams and behavioral view model by the activity, use case, state, and sequence diagram. However, UML does not provide the formal syntax, therefore its semantics is not formally definable, so for assure of correctness, we need to incorporate semantic reasoning through verification, specification...

  6. Formal Verification of NTRUEncrypt Scheme

    Directory of Open Access Journals (Sweden)

    Gholam Reza Moghissi

    2016-04-01

    Full Text Available In this paper we explore a mechanized verification of the NTRUEncrypt scheme, with the formal proof system Isabelle/HOL. More precisely, the functional correctness of this algorithm, in its reduced form, is formally verified with computer support. We show that this scheme is correct what is a necessary condition for the usefulness of any cryptographic encryption scheme. Besides, we present a convenient and application specific formalization of the NTRUEncrypt scheme in the Isabelle/HOL system that can be used in further study around the functional and security analysis of NTRUEncrypt family.

  7. An Effective Fingerprint Verification Technique

    CERN Document Server

    Gogoi, Minakshi

    2010-01-01

    This paper presents an effective method for fingerprint verification based on a data mining technique called minutiae clustering and a graph-theoretic approach to analyze the process of fingerprint comparison to give a feature space representation of minutiae and to produce a lower bound on the number of detectably distinct fingerprints. The method also proving the invariance of each individual fingerprint by using both the topological behavior of the minutiae graph and also using a distance measure called Hausdorff distance.The method provides a graph based index generation mechanism of fingerprint biometric data. The self-organizing map neural network is also used for classifying the fingerprints.

  8. A verification environment for bigraphs

    DEFF Research Database (Denmark)

    Perrone, Gian David; Debois, Søren; Hildebrandt, Thomas

    2013-01-01

    We present the BigMC tool for bigraphical reactive systems that may be instantiated as a verification tool for any formalism or domain-specific modelling language encoded as a bigraphical reactive system. We introduce the syntax and use of BigMC, and exemplify its use with two small examples......: a textbook “philosophers” example, and an example motivated by a ubiquitous computing application. We give a tractable heuristic with which to approximate interference between reaction rules, and prove this analysis to be safe. We provide a mechanism for state reachability checking of bigraphical reactive...

  9. Tipificación molecular del virus dengue 3 durante el brote epidémico de dengue clásico en Lima, Perú, 2005

    Directory of Open Access Journals (Sweden)

    Enrique Mamani Z

    2005-07-01

    Full Text Available Objetivos: Identificar mediante trascripción reversa-reacción en cadena de la polimerasa (RT-PCR y sitios específicos de restricción - reacción en cadena de la polimerasa (RSS-PCR al agente causal del brote epidémico presentado en el distrito de Comas, Lima en abril del año 2005. Materiales y métodos: veinte muestras de suero colectadas durante el brote de dengue fueron procesados por RT-PCR para determinar el serotipo, esta técnica se realizó en un solo paso. Luego se aplicó la técnica RSS-PCR para la identificación del genotipo circulante y se corroboraron los resultados posteriormente con aislamiento viral y secuenciamiento. Resultados: El análisis del RTPCR del ARN extraído de las muestras presentó un producto amplificado de 290pb que corresponden al dengue serotipo 3 (DEN 3. El análisis de los productos de RSS-PCR del ARN extraído a partir de aislamientos de DEN 3 correspondió al patrón C, incluido en el genotipo III. Los aislamientos de los virus dengue 3 en líneas celulares C6/36, tipificadas por IFI y el secuenciamiento genético confirmaron los resultados obtenidos por las pruebas previamente descritas. Conclusión: Durante el brote epidémico de dengue clásico en Lima, circuló el genotipo III del virus DEN 3.

  10. Euroscepticism Online

    DEFF Research Database (Denmark)

    Dutceac Segesten, Anamaria; Bossetta Jr, Michael Joseph

    -criticism between Sweden and Denmark? Methodologically we combine quantitative and qualitative content analysis of the forum discussions pertaining to the EU critique taking place on the two platforms respectively. Our focus is thus not on the republished content originated in traditional media channels...... states, leading to numerous street protests. The internet is another site where EU contestation takes place.In the present paper we propose to compare two online platform consisting of user-generated content, where the exchange of ideas and opinions is unfiltered and largely unmoderated. Flashback...... is the leading online discussion forum in Sweden and one of the most popular sites of interaction for those euroskeptic voices coming from the right side of the political spectrum. 180grader is its Danish equivalent. Our research question is: Are there any differences in the discourse surrounding EU...

  11. Euroscepticism Online

    DEFF Research Database (Denmark)

    Dutceac Segesten, Anamaria; Bossetta Jr, Michael Joseph

    -criticism between Sweden and Denmark? Methodologically we combine quantitative and qualitative content analysis of the forum discussions pertaining to the EU critique taking place on the two platforms respectively. Our focus is thus not on the republished content originated in traditional media channels...... states, leading to numerous street protests. The internet is another site where EU contestation takes place.In the present paper we propose to compare two online platform consisting of user-generated content, where the exchange of ideas and opinions is unfiltered and largely unmoderated. Flashback...... and nationalism as the two poles on a continuum of attitudes coming out of the discourses. We discuss finally the consequences of the expected Swedish-Danish divergence of online debate content for the idea of a unified European public sphere....

  12. Online kinship

    DEFF Research Database (Denmark)

    Andreassen, Rikke

    2016-01-01

    The article shows how the technology of social media sites facilitates new kinds of kinship. It ana-lyzes how ‘donor families’ – i.e., families in which the children are conceived via sperm and/or egg donations – negotiate kinship, family formations and gender when connecting with each other online....... Family formation and parenting are closely connected with gender and gender norms, and online donor families, therefore, offer an opportunity for understanding gender and gender for-mations in contemporary times and contemporary media. By analyzing commentary threads of a Facebook group connecting donor...... families as well as interviews with users of this Facebook group, the article shows how the affordances of social media, especially the Facebook application for smart phones, are central to the formation and maintenance of new kinship relations. Furthermore, the article illustrates how conventional...

  13. Verification Support for Object Database Design

    NARCIS (Netherlands)

    Spelt, David

    1999-01-01

    In this thesis we have developed a verification theory and a tool for the automated analysis of assertions about object-oriented database schemas. The approach is inspired by the work of [SS89] in which a theorem prover is used to automate the verification of invariants for transactions on a relatio

  14. DATA VERIFICATION IN ISSUE SUPERVISING SYSTEMS

    Directory of Open Access Journals (Sweden)

    R. S. Katerinenko

    2013-01-01

    Full Text Available The paper proposes a method of data verification in issues tracking systems by means of production rules. This model makes it possible to formulate declaratively conditions that the information containment should comply with and apply reasoning procedures. Practical application of proposed verification system in a real software development project is described.

  15. On Verification Modelling of Embedded Systems

    NARCIS (Netherlands)

    Brinksma, Ed; Mader, Angelika

    2004-01-01

    Computer-aided verification of embedded systems hinges on the availability of good verification models of the systems at hand. Such models must be much simpler than full design models or specifications to be of practical value, because of the unavoidable combinatorial complexities in the verificatio

  16. Face verification for mobile personal devices

    NARCIS (Netherlands)

    Tao, Qian

    2009-01-01

    In this thesis, we presented a detailed study of the face verification problem on the mobile device, covering every component of the system. The study includes face detection, registration, normalization, and verification. Furthermore, the information fusion problem is studied to verify face sequenc

  17. A Correlation-Based Fingerprint Verification System

    NARCIS (Netherlands)

    Bazen, Asker M.; Verwaaijen, Gerben T.B.; Gerez, Sabih H.; Veelenturf, Leo P.J.; Zwaag, van der Berend Jan

    2000-01-01

    In this paper, a correlation-based fingerprint verification system is presented. Unlike the traditional minutiae-based systems, this system directly uses the richer gray-scale information of the fingerprints. The correlation-based fingerprint verification system first selects appropriate templates i

  18. A Model for Collaborative Runtime Verification

    NARCIS (Netherlands)

    Testerink, Bas; Bulling, Nils; Dastani, Mehdi

    2015-01-01

    Runtime verification concerns checking whether a system execution satisfies a given property. In this paper we propose a model for collaborative runtime verification where a network of local monitors collaborates in order to verify properties of the system. A local monitor has only a local view on

  19. A Model for Collaborative Runtime Verification

    NARCIS (Netherlands)

    Testerink, Bas; Bulling, Nils; Dastani, Mehdi

    2015-01-01

    Runtime verification concerns checking whether a system execution satisfies a given property. In this paper we propose a model for collaborative runtime verification where a network of local monitors collaborates in order to verify properties of the system. A local monitor has only a local view on t

  20. Verification and Performance Analysis for Embedded Systems

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand

    2009-01-01

    This talk provides a thorough tutorial of the UPPAAL tool suite for, modeling, simulation, verification, optimal scheduling, synthesis, testing and performance analysis of embedded and real-time systems.......This talk provides a thorough tutorial of the UPPAAL tool suite for, modeling, simulation, verification, optimal scheduling, synthesis, testing and performance analysis of embedded and real-time systems....

  1. SU-E-T-133: Assessing IMRT Treatment Delivery Accuracy and Consistency On a Varian TrueBeam Using the SunNuclear PerFraction EPID Dosimetry Software

    Energy Technology Data Exchange (ETDEWEB)

    Dieterich, S [UC Davis Medical Center, Sacramento, CA (United States); Trestrail, E; Holt, R [Pacific Crest Medical Physics, Chico, CA (United States); Saini, S [Sun Nuclear Corporation, Melbourne, FL (Australia); Pfeiffer, I [VMTH, UC Davis, Davis, CA (United States); Kent, M; Hansen, K [Surgical and Radiological Sciences, UC Davis, Davis, CA (United States)

    2015-06-15

    Purpose: To assess if the TrueBeam HD120 collimator is delivering small IMRT fields accurately and consistently throughout the course of treatment using the SunNuclear PerFraction software. Methods: 7-field IMRT plans for 8 canine patients who passed IMRT QA using SunNuclear Mapcheck DQA were selected for this study. The animals were setup using CBCT image guidance. The EPID fluence maps were captured for each treatment field and each treatment fraction, with the first fraction EPID data serving as the baseline for comparison. The Sun Nuclear PerFraction Software was used to compare the EPID data for subsequent fractions using a Gamma (3%/3mm) pass rate of 90%. To simulate requirements for SRS, the data was reanalyzed using a Gamma (3%/1mm) pass rate of 90%. Low-dose, low- and high gradient thresholds were used to focus the analysis on clinically relevant parts of the dose distribution. Results: Not all fractions could be analyzed, because during some of the treatment courses the DICOM tags in the EPID images intermittently change from CU to US (unspecified), which would indicate a temporary loss of EPID calibration. This technical issue is still being investigated. For the remaining fractions, the vast majority (7/8 of patients, 95% of fractions, and 96.6% of fields) are passing the less stringent Gamma criteria. The more stringent Gamma criteria caused a drop in pass rate (90 % of fractions, 84% of fields). For the patient with the lowest pass rate, wet towel bolus was used. Another patient with low pass rates experienced masseter muscle wasting. Conclusion: EPID dosimetry using the PerFraction software demonstrated that the majority of fields passed a Gamma (3%/3mm) for IMRT treatments delivered with a TrueBeam HD120 MLC. Pass rates dropped for a DTA of 1mm to model SRS tolerances. PerFraction pass rates can flag missing bolus or internal shields. Sanjeev Saini is an employee of Sun Nuclear Corporation. For this study, a pre-release version of PerFRACTION 1

  2. RISKIND verification and benchmark comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Biwer, B.M.; Arnish, J.J.; Chen, S.Y.; Kamboj, S.

    1997-08-01

    This report presents verification calculations and benchmark comparisons for RISKIND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the population from exposures associated with the transportation of spent nuclear fuel and other radioactive materials. Spreadsheet calculations were performed to verify the proper operation of the major options and calculational steps in RISKIND. The program is unique in that it combines a variety of well-established models into a comprehensive treatment for assessing risks from the transportation of radioactive materials. Benchmark comparisons with other validated codes that incorporate similar models were also performed. For instance, the external gamma and neutron dose rate curves for a shipping package estimated by RISKIND were compared with those estimated by using the RADTRAN 4 code and NUREG-0170 methodology. Atmospheric dispersion of released material and dose estimates from the GENII and CAP88-PC codes. Verification results have shown the program to be performing its intended function correctly. The benchmark results indicate that the predictions made by RISKIND are within acceptable limits when compared with predictions from similar existing models.

  3. Cognitive Bias in Systems Verification

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Working definition of cognitive bias: Patterns by which information is sought and interpreted that can lead to systematic errors in decisions. Cognitive bias is used in diverse fields: Economics, Politics, Intelligence, Marketing, to name a few. Attempts to ground cognitive science in physical characteristics of the cognitive apparatus exceed our knowledge. Studies based on correlations; strict cause and effect is difficult to pinpoint. Effects cited in the paper and discussed here have been replicated many times over, and appear sound. Many biases have been described, but it is still unclear whether they are all distinct. There may only be a handful of fundamental biases, which manifest in various ways. Bias can effect system verification in many ways . Overconfidence -> Questionable decisions to deploy. Availability -> Inability to conceive critical tests. Representativeness -> Overinterpretation of results. Positive Test Strategies -> Confirmation bias. Debiasing at individual level very difficult. The potential effect of bias on the verification process can be managed, but not eliminated. Worth considering at key points in the process.

  4. Cognitive Bias in Systems Verification

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Working definition of cognitive bias: Patterns by which information is sought and interpreted that can lead to systematic errors in decisions. Cognitive bias is used in diverse fields: Economics, Politics, Intelligence, Marketing, to name a few. Attempts to ground cognitive science in physical characteristics of the cognitive apparatus exceed our knowledge. Studies based on correlations; strict cause and effect is difficult to pinpoint. Effects cited in the paper and discussed here have been replicated many times over, and appear sound. Many biases have been described, but it is still unclear whether they are all distinct. There may only be a handful of fundamental biases, which manifest in various ways. Bias can effect system verification in many ways . Overconfidence -> Questionable decisions to deploy. Availability -> Inability to conceive critical tests. Representativeness -> Overinterpretation of results. Positive Test Strategies -> Confirmation bias. Debiasing at individual level very difficult. The potential effect of bias on the verification process can be managed, but not eliminated. Worth considering at key points in the process.

  5. Practical approach for pretreatment verification of IMRT with flattening filter free(FFF) beams using Varian Portal Dosimetry.

    Science.gov (United States)

    Min, Soonki; Choi, Young Eun; Kwak, Jungwon; Cho, Byungchul

    2014-01-08

    Patient-specific pretreatment verification of intensity-modulated radiation therapy (IMRT) or volumetric-modulated arc therapy (VMAT) is strongly recommended for all patients in order to detect any potential errors in treatment planning process and machine deliverability, and is thus performed routinely in many clinics. Portal dosimetry is an effective method for this purpose because of its prompt setup, easy data acquisition, and high spatial resolution. However, portal dosimetry cannot be applied to IMRT or VMAT with flattening filter-free (FFF) beams because of the high dose-rate saturation effect of the electronic portal imaging device (EPID). In our current report, we suggest a practical QA method of expanding the conventional portal dosimetry to FFF beams with a QA plan generated by the following three steps: 1) replace the FFF beams with flattening filtered (FF) beams of the same nominal energy; 2) reduce the dose rate to avoid the saturation effect of the EPID detector; and 3) adjust the total MU to match the gantry and MLC leaf motions. Two RapidArc plans with 6 and 10 MV FFF beams were selected, and QA plans were created by the aforementioned steps and delivered. The trajectory log files of TrueBeam obtained during the treatment and during the delivery of QA plan were analyzed and compared. The maximum discrepancies in the expected trajectories between the treatment and QA plans were within 0.002 MU for the MU, 0.06° for the motion of gantry rotation, and 0.006 mm for the positions of the MLC leaves, indicating much higher levels of accuracy compared to the mechanical specifications of the machine. For further validation of the method, direct comparisons of the delivered QA FF beam to the treatment FFF beam were performed using film dosimetry and show that gamma passing rates under 2%/2 mm criteria are 99.0%-100% for the all four arc beams. This method can be used on RapidArc plans with FFF beams without any additional procedure or modifications on the

  6. Expressão das citoceratinas em dermatoses infecto- parasitárias associadas à hiperplasia epidérmica Expression of the cytokeratins in infectious and parasitic skin diseases associated with epidermal hyperplasia

    Directory of Open Access Journals (Sweden)

    Maria Christina Marques Nogueira-Castañon

    2004-12-01

    Full Text Available FUNDAMENTOS: As citoceratinas(C são as proteínas estruturais mais importantes das células epiteliais e exibem a maior heterogeneidade dentre todas as proteínas dos filamentos intermediários. Seu estudo através de imunomarcação possibilita a análise estrutural do citoesqueleto em vários afecções neoplásicas e inflamatórias. OBJETIVOS: Verificar o padrão imuno-histoquímico da expressão das citoceratinas na epiderme de doenças infecto-parasitárias associadas à hiperplasia escamosa. MÉTODOS: Cortes histológicos obtidos de tecidos pré-fixados e incluidos em parafina à partir de lesões de cromomicose, paracoccidioidomicose, leishmaniose e condiloma acuminado foram marcados com os anticorpos DEK10, LL025, LL002 e AE1 pela técnica de imunoperoxidase (avidina-biotina. RESULTADOS: A análise de áreas com intensidade variável de hiperplasia epidérmica presentes nos fragmentos mostrou exclusivamente e/ou predominantemente nas quatro doenças: ausência de expressão da C10 nas áreas de hiperplasia intensa e retardo da expressão nas áreas de hiperplasia moderada e/ou ausente; padrão suprabasal de marcação para a C16 independentemente do grau de hiperplasia como também, liberação de epítopos suprabasais para os marcadores LL002 (C14 e AE1 (C10,14,16,19. CONCLUSÕES: As modificações indicam que, independentemente da natureza do agente etiológico e do grau de hiperplasia presente, ocorrem alterações na diferenciação e proliferação do ceratinócito.BACKGROUND: Cytokeratins (K are the major structural proteins of epithelial cells and they display the greatest heterogeneity of all intermediate filament proteins. The study of many isolated cytokeratins by immunomarcation enables the structural verification of the cytoskeleton in many neoplastic and inflammatory diseases. OBJECTIVE: To verify the immunohistochemical pattern of cytokeratin expression in infectious and parasitic diseases associated with squamous

  7. Gorging Online

    Institute of Scientific and Technical Information of China (English)

    Pride; Phiri

    2011-01-01

    MY introduction to social networking came in my first year of university.I had never been online before then nor used a computer extensively. The archaic machines at my high school had been good for a few rounds of solitaire and nothing more.Growing up in Zimbabwe at the turn of the century where even cell phones were a novelty,the Internet was just something you read about and then added to the list of things that while nice to have,didn’t really factor into everyday life.

  8. A critical evaluation of the PTW 2D-ARRAY seven29 and OCTAVIUS II phantom for IMRT and VMAT verification.

    Science.gov (United States)

    Hussein, Mohammad; Adams, Elizabeth J; Jordan, Thomas J; Clark, Catharine H; Nisbet, Andrew

    2013-11-04

    Quality assurance (QA) for intensity- and volumetric-modulated radiotherapy (IMRT and VMAT) has evolved substantially. In recent years, various commercial 2D and 3D ionization chamber or diode detector arrays have become available, allowing for absolute verification with near real time results, allowing for streamlined QA. However, detector arrays are limited by their resolution, giving rise to concerns about their sensitivity to errors. Understanding the limitations of these devices is therefore critical. In this study, the sensitivity and resolution of the PTW 2D-ARRAY seven29 and OCTAVIUS II phantom combination was comprehensively characterized for use in dynamic sliding window IMRT and RapidArc verification. Measurement comparisons were made between single acquisition and a multiple merged acquisition techniques to improve the effective resolution of the 2D-ARRAY, as well as comparisons against GAFCHROMIC EBT2 film and electronic portal imaging dosimetry (EPID). The sensitivity and resolution of the 2D-ARRAY was tested using two gantry angle 0° modulated test fields. Deliberate multileaf collimator (MLC) errors of 1, 2, and 5 mm and collimator rotation errors were inserted into IMRT and RapidArc plans for pelvis and head & neck sites, to test sensitivity to errors. The radiobiological impact of these errors was assessed to determine the gamma index passing criteria to be used with the 2D-ARRAY to detect clinically relevant errors. For gamma index distributions, it was found that the 2D-ARRAY in single acquisition mode was comparable to multiple acquisition modes, as well as film and EPID. It was found that the commonly used gamma index criteria of 3% dose difference or 3 mm distance to agreement may potentially mask clinically relevant errors. Gamma index criteria of 3%/2 mm with a passing threshold of 98%, or 2%/2 mm with a passing threshold of 95%, were found to be more sensitive. We suggest that the gamma index passing thresholds may be used for guidance

  9. Efecto de dos temperaturas de almacenamientos (5 y 20 °C) de epidídimos provenientes de toros de matadero sobre la calidad y congelabilidad de espermatozoides

    OpenAIRE

    Valverde Peralta, Edwin Enrique

    2016-01-01

    En esta investigación se evaluó la calidad espermática post-descongelación de espermatozoides de la cola del epidídimo de toros de matadero sometidos a dos temperaturas de almacenamiento (5oC y 20oC). Se colectó 8 pares de testículos se almacenó herméticamente en bolsas plásticas con Lactato Ringer por 6 horas. Los gametos fueron recuperados por flujo retrógrado de la cola del epidídimo se evaluó concentración, viabilidad espermática, se procesó ajustando a dosis de 50 x 106 esp/0,25ml con ...

  10. Retail applications of signature verification

    Science.gov (United States)

    Zimmerman, Thomas G.; Russell, Gregory F.; Heilper, Andre; Smith, Barton A.; Hu, Jianying; Markman, Dmitry; Graham, Jon E.; Drews, Clemens

    2004-08-01

    The dramatic rise in identity theft, the ever pressing need to provide convenience in checkout services to attract and retain loyal customers, and the growing use of multi-function signature captures devices in the retail sector provides favorable conditions for the deployment of dynamic signature verification (DSV) in retail settings. We report on the development of a DSV system to meet the needs of the retail sector. We currently have a database of approximately 10,000 signatures collected from 600 subjects and forgers. Previous work at IBM on DSV has been merged and extended to achieve robust performance on pen position data available from commercial point of sale hardware, achieving equal error rates on skilled forgeries and authentic signatures of 1.5% to 4%.

  11. MFTF sensor verification computer program

    Energy Technology Data Exchange (ETDEWEB)

    Chow, H.K.

    1984-11-09

    The design, requirements document and implementation of the MFE Sensor Verification System were accomplished by the Measurement Engineering Section (MES), a group which provides instrumentation for the MFTF magnet diagnostics. The sensors, installed on and around the magnets and solenoids, housed in a vacuum chamber, will supply information about the temperature, strain, pressure, liquid helium level and magnet voltage to the facility operator for evaluation. As the sensors are installed, records must be maintained as to their initial resistance values. Also, as the work progresses, monthly checks will be made to insure continued sensor health. Finally, after the MFTF-B demonstration, yearly checks will be performed as well as checks of sensors as problem develops. The software to acquire and store the data was written by Harry Chow, Computations Department. The acquired data will be transferred to the MFE data base computer system.

  12. Formal Verification of UML Profil

    DEFF Research Database (Denmark)

    Bhutto, Arifa; Hussain, Dil Muhammad Akbar

    2011-01-01

    The Unified Modeling Language (UML) is based on the Model Driven Development (MDD) approach which capturing the system functionality using the platform-independent model (PMI) and appropriate domain-specific languages. In UML base system notations, structural view is model by the class, components...... and object diagrams and behavioral view model by the activity, use case, state, and sequence diagram. However, UML does not provide the formal syntax, therefore its semantics is not formally definable, so for assure of correctness, we need to incorporate semantic reasoning through verification, specification......, refinement, and incorporate into the development process. Our motivation of research is to make an easy structural view and suggest formal technique/ method which can be best applied or used for the UML based development system. We investigate the tools and methods, which broadly used for the formal...

  13. 37 CFR 260.5 - Verification of statements of account.

    Science.gov (United States)

    2010-07-01

    ... Verification of statements of account. (a) General. This section prescribes general rules pertaining to the... party requesting the verification procedure shall retain the report of the verification for a period of... independent auditor, shall serve as an acceptable verification procedure for all parties. (f) Costs of the...

  14. 37 CFR 382.6 - Verification of royalty payments.

    Science.gov (United States)

    2010-07-01

    ... payments. (a) General. This section prescribes general rules pertaining to the verification of the payment... requesting the verification procedure shall retain the report of the verification for a period of three years... independent auditor, shall serve as an acceptable verification procedure for all interested parties. (f) Costs...

  15. Arms control verification: The technologies that make it possible

    Energy Technology Data Exchange (ETDEWEB)

    Tsipis, K.; Hafemeister, D.W.; Janeway, P.

    1986-01-01

    This book presents papers on arms control verification. Topics considered include the politics of treaty verification and compliance, national security, remote sensing, image processing, image enhancement by digital computer, charge-coupled device image sensors, radar imaging, infrared surveillance, monitoring, seismological aspects, satellite verifications, seismic verification, and verifying a fissile material production freeze.

  16. On the verification of polynomial system solvers

    Institute of Scientific and Technical Information of China (English)

    Changbo CHEN; Marc MORENO MAZA; Wei PAN; Yuzhen XI

    2008-01-01

    We discuss the verification of mathematical software solving polynomial systems symbolically by way of triangular decomposition. Standard verification techniques are highly resource consuming and apply only to polynomial systems which are easy to solve. We exhibit a new approach which manipulates constructible sets represented by regular systems. We provide comparative benchmarks of different verification procedures applied to four solvers on a large set of well-known polynomial systems. Our experimental results illustrate the high effi-ciency of our new approach. In particular, we are able to verify triangular decompositions of polynomial systems which are not easy to solve.

  17. Liquefied Natural Gas (LNG) dispenser verification device

    Science.gov (United States)

    Xiong, Maotao; Yang, Jie-bin; Zhao, Pu-jun; Yu, Bo; Deng, Wan-quan

    2013-01-01

    The composition of working principle and calibration status of LNG (Liquefied Natural Gas) dispenser in China are introduced. According to the defect of weighing method in the calibration of LNG dispenser, LNG dispenser verification device has been researched. The verification device bases on the master meter method to verify LNG dispenser in the field. The experimental results of the device indicate it has steady performance, high accuracy level and flexible construction, and it reaches the international advanced level. Then LNG dispenser verification device will promote the development of LNG dispenser industry in China and to improve the technical level of LNG dispenser manufacture.

  18. Poster — Thur Eve — 10: Partial kV CBCT, complete kV CBCT and EPID in breast treatment: a dose comparison study for skin, breasts, heart and lungs

    Energy Technology Data Exchange (ETDEWEB)

    Roussin, E; Archambault, L K; Wierzbicki, W [Hopital Maisonneuve Rosemont, Montreal, Quebec (Canada)

    2014-08-15

    The advantages of kilovoltage cone beam CT (kV CBCT) imaging over electronic portal imaging device (EPID) such as accurate 3D anatomy, soft tissue visualization, fast rigid registration and enhanced precision on patient positioning has lead to its increasing use in clinics. The benefits of this imaging technique are at the cost of increasing the dose to healthy surrounding organs. Our center has moved toward the use of daily partial rotation kV CBCT to restrict the dose to healthy tissues. This study aims to better quantify radiation doses from different image-guidance techniques such as tangential EPID, complete and partial kV CBCT for breast treatments. Cross-calibrated ionization chambers and kV calibrated Gafchromic films were used to measure the dose to the heart, lungs, breasts and skin. It was found that performing partial kV CBCT decreases the heart dose by about 36%, the lungs dose by 31%, the contralateral breast dose by 41% and the ipsilateral breast dose by 43% when compared to a full rotation CBCT. The skin dose measured for a full rotation CBCT was about 0.8 cGy for the contralateral breast and about 0.3 cGy for the ipsilateral breast. The study is still ongoing and results on skin doses for partial rotation kV CBCT as well as for tangential EPID images are upcoming.

  19. Paarberatung online

    Directory of Open Access Journals (Sweden)

    Josef Lang

    2005-09-01

    Full Text Available Auf dem Hintergrund der Fragestellungen und der Entwicklung von Beratungsangeboten im Internet generell wird das Spezifische der Paarberatung im Internet dargestellt. Die bekanntesten Angebote in deutscher Sprache werden vorgestellt. In einem Schwerpunkt wird das Konzept von „www.paarberatung.ch“ skizziert. Angebote unterscheiden sich in ihren Zielsetzungen, die auf die unterschiedlichen Erwartungen der Ratsuchenden ausgerichtet sind und auf jede Anfrage zugeschnitten werden. Methodische Leitlinien sind aus der Beratungspsychologie mit Blick auf das Medium Internet abgeleitet.Der Autor bevorzugt den systemischen Ansatz, integriert Methoden des kognitiv-verhaltenstherapeutischen Beratungsansatzes und plädiert dafür, die personspezifischen Elemente einer Anfrage für die Antwort zu nutzen. Grundsätzliches zur Psychologie der Paarberatung und zur Textinterpretation bei einer E-Mail-Beratung wird veranschaulicht mit einem konkreten Beispiel aus der Online-praxis und einer kurzen Beschreibung der Population der Ratsuchenden.

  20. Online Innovation

    DEFF Research Database (Denmark)

    Vujovic, Sladjana; Ulhøi, John Parm

    2008-01-01

    on proprietary knowledge. Design/methodology/approach - The paper borrows from the theory of communities-of-practice, which takes into account social relations, contacts, and the transfer and incorporation of knowledge. Open source innovation is not the exclusive preserve of computer nerds, but also has...... implications for existing software manufacturers. The paper therefore includes the case of IBM, a company which has successfully integrated this new and more open way of collaboration into its business model. Findings - The paper concludes that online computer-based innovation fundamentally challenges current...... for practitioners directly involved in innovation and product development. Originality/value - This paper develops a conceptual framework for understanding product development based on non-proprietary knowledge, which cannot be adequately accounted for by traditional corporate innovation theory alone....

  1. Cistoadenoma papilar de epidídimo: a propósito de un caso Papillary cystadenoma of the epididymis: a case report

    Directory of Open Access Journals (Sweden)

    Daniela Stoisa

    2012-12-01

    Full Text Available Presentamos un caso de cistoadenoma papilar de epidídimo (CPE en un paciente varón de 44 años de edad con una masa palpable en el escroto derecho. La ecografía (US y la resonancia magnética (RM mostraron tres lesiones quísticas adyacentes extratesticulares de paredes gruesas, una con un fino septo parcial interno, de ubicación epididimaria y un diámetro en conjunto de 1 cm x 0,4 cm. El diagnóstico anatomopatológico realizado luego de su resección quirúrgica fue de cistoadenoma papilar de epidídimo. Éste consiste en un tumor epitelial benigno, muy poco frecuente, que se origina del epitelio ductal eferente. Se presenta preferentemente en el adulto joven y puede ser uni o bilateral (un tercio de los casos, así como también esporádico o hereditario en relación con la enfermedad de von Hippel-Lindau, particularmente en el caso de las lesiones bilaterales. Se diagnostica por palpación y métodos por imágenes, incluyendo la ecografía y la resonanacia magnética. Histológicamente se caracteriza por la presencia de espacios quísticos con proyecciones papilares internas, revestidas por células claras, que remedan a las del carcinoma renal. La diferenciación entre éste y el cisto-adenoma papilar de epidídimo debe hacerse a través de marcadores inmunohistoquímicos. El tratamiento es la exéresis quirúrgica y un posterior seguimiento, ya que, si bien su pronóstico es excelente, se ha descrito su transformación maligna a cistoadenocarcinoma.We report a case of papillary cystadenoma of the epididymis (PCE in a 44-year-old male patient with a palpable right intrascrotal mass. Ultrasound and magnetic resonance imaging showed three extratesticular intraepididymal thick wall-cystic lesions measuring 1.0 x 0.4 cm overall. After surgical resection, the pathological diagnosis was papillary cystadenoma of epididymis. This is a rare benign epithelial tumor that arises from the efferent duct epithelium. It usually occurs in young adult

  2. Engineering drawing field verification program. Revision 3

    Energy Technology Data Exchange (ETDEWEB)

    Ulk, P.F.

    1994-10-12

    Safe, efficient operation of waste tank farm facilities is dependent in part upon the availability of accurate, up-to-date plant drawings. Accurate plant drawings are also required in support of facility upgrades and future engineering remediation projects. This supporting document establishes the procedure for performing a visual field verification of engineering drawings, the degree of visual observation being performed and documenting the results. A copy of the drawing attesting to the degree of visual observation will be paginated into the released Engineering Change Notice (ECN) documenting the field verification for future retrieval and reference. All waste tank farm essential and support drawings within the scope of this program will be converted from manual to computer aided drafting (CAD) drawings. A permanent reference to the field verification status will be placed along the right border of the CAD-converted drawing, referencing the revision level, at which the visual verification was performed and documented.

  3. MAMA Software Features: Quantification Verification Documentation-1

    Energy Technology Data Exchange (ETDEWEB)

    Ruggiero, Christy E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Porter, Reid B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-05-21

    This document reviews the verification of the basic shape quantification attributes in the MAMA software against hand calculations in order to show that the calculations are implemented mathematically correctly and give the expected quantification results.

  4. Tackling Verification and Validation for Prognostics

    Data.gov (United States)

    National Aeronautics and Space Administration — Verification and validation (V&V) has been identified as a critical phase in fielding systems with Integrated Systems Health Management (ISHM) solutions to...

  5. Procedure Verification and Validation Toolset Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed research is aimed at investigating a procedure verification and validation toolset, which will allow the engineers who are responsible for developing...

  6. Seismic design verification of LMFBR structures

    Energy Technology Data Exchange (ETDEWEB)

    1977-07-01

    The report provides an assessment of the seismic design verification procedures currently used for nuclear power plant structures, a comparison of dynamic test methods available, and conclusions and recommendations for future LMFB structures.

  7. Calibration and verification of environmental models

    Science.gov (United States)

    Lee, S. S.; Sengupta, S.; Weinberg, N.; Hiser, H.

    1976-01-01

    The problems of calibration and verification of mesoscale models used for investigating power plant discharges are considered. The value of remote sensors for data acquisition is discussed as well as an investigation of Biscayne Bay in southern Florida.

  8. MAMA Software Features: Quantification Verification Documentation-1

    Energy Technology Data Exchange (ETDEWEB)

    Ruggiero, Christy E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Porter, Reid B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-05-21

    This document reviews the verification of the basic shape quantification attributes in the MAMA software against hand calculations in order to show that the calculations are implemented mathematically correctly and give the expected quantification results.

  9. Environmental Technology Verification Program (ETV) Policy Compendium

    Science.gov (United States)

    The Policy Compendium summarizes operational decisions made to date by participants in the U.S. Environmental Protection Agency's (EPA's) Environmental Technology Verification Program (ETV) to encourage consistency among the ETV centers. The policies contained herein evolved fro...

  10. ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) PROGRAM: FUEL CELLS

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) Environmental Technology Verification (ETV) Program evaluates the performance of innovative air, water, pollution prevention and monitoring technologies that have the potential to improve human health and the environment. This techno...

  11. Standard Verification System Lite (SVS Lite)

    Data.gov (United States)

    Social Security Administration — SVS Lite is a mainframe program used exclusively by the Office of Child Support Enforcement (OCSE) to perform batch SSN verifications. This process is exactly the...

  12. SU-E-J-64: Evaluation of a Commercial EPID-Based in Vivo Dosimetric System in the Presence of Lung Tissue Heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno-Olmos, J; Palomo-Llinares, R; Candela-Juan, C; Carmona Meseguer, V; Lliso-Valverde, F [Hospital Universitari i Politecnic La Fe, Valencia, Valencia (Spain); Garcia-Martinez, T [Hospital de la Ribera, Alzira, Valencia (Spain); Richart-Sancho, J [Clinica Benidorm, Benidorm, Alicante (Spain); Ballester, F [University of Valencia, Burjassot (Spain); Perez-Calatayud, J [Hospital Universitari i Politecnic La Fe, Valencia, Valencia (Spain); Clinica Benidorm, Benidorm, Alicante (Spain)

    2014-06-01

    Purpose: To study the performance of Dosimetry Check (DC), an EPID-based dosimetry software, which allows performing transit dosimetry, in low density medium, by comparing calculations in-phantom, and analysing results for 15 lung patients. Methods: DC software (v.3.8, pencil beam-based algorithm) has been tested, for plans (Eclipse v.10.0 TPS) delivered in two Varian Clinac iX equipped with aS1000 EPIDs.In the CIRS lung phantom, comparisons between DC and Eclipse (Acuros) were performed for several plans: (1) four field box; (2) square field delivered in arc mode; (3) RapidArc lung patient plan medially centred; (4) RapidArc lung patient plan centred in one lung. Reference points analysed: P1 (medial point, plans 1–3) and P2 (located inside one lung, plan 4).For fifteen lung patients treated with RapidArc, the isocentre and 9 additional points inside the PTV as well as the gamma passing rate (3%/3mm) for the PTV and at the main planes were studied. Results: In-phantom:P1: Per-field differences in plan 1: good agreement for AP-PA fields; discrepancy of 7% for the lateral fields. Global differences (plans 1–3): about 4%, showing a compensating effect of the individual differences.P2: Global difference (plan 4): 15 %. This represents the worst case situation as it is a point surrounded by lung tissue, where the DC pencil beam algorithm is expected to give the greater difference against Acuros.Lung patients: Mean point difference inside the PTV:(5.4±4.2) %. Gamma passing rate inside the PTV:(45±12) %. Conclusion: The performance of DC in heterogeneous lung medium was studied with a special phantom and the results for 15 patients were analysed. The found deviations show that even though DC is a highly promising in vivo dosimetry tool, there is a need of incorporating a more accurate algorithm mainly for plans with low density regions involved.

  13. Surto epidêmico de gastrenterite, com identificação do provável alimento veiculador da infecção

    Directory of Open Access Journals (Sweden)

    Anastácio F. Morgado

    1982-12-01

    Full Text Available Descreve-se um surto epidêmico de gastrenterite entre pessoas adultas, com um total de 52 casos, todos iniciando-se até 24 horas após terem ingerido um alimento provavelmente contaminado. Clinicamente, a doença caracterizou-se por dor abdominal em cólicas, urgência para evacuar, e missão de fezes diarreicas, febre e adinamia, que persistiram por um a tres dias. Todos os casos foram benignos, sem uma só complicação e nenhum tem necessidade de tratamento hospitalar. Foram feitos exames bacteriológicos das fezes de alguns casos, mas não se isolou qualquer germe; esses casos, porém, já estavam em convalescença ou em uso de antibióticos. Todos os casos tinham em comum o fato de terem almoçado ou feito lanche em um mesmo restaurante. Comparou-se, então, 109 pessoas que haviam almoçado, e 70 que haviam feito lanche, com 107 pessoas, do mesmo ambiente dos comensais, que não almoçaram nem lancharam. A associação com fato de almoçar ou lanchar no restaurante foi inequívoca. Ademais, em um número de pessoas bem maior do que os comensais, bebendo da mesma água, não surgiu um só caso de gastroenterite. As 109 pessoas que almoçaram responderam quais os alimentos que haviam ingerido, o que permitiu identificar a carne assada, servida no almoço, como sendo o veiculo provável da infecção. Infelizmente, não se conseguiu restos dessa carne assada para que se pudesse tentar isolar germes. A mediana do período de incubação foi 10,4 horas e os períodos de incubação máximo e mínimo foram de 24 e 0,5 horas, respectivamente; a distribuição cronológica dos casos lembra muito o perfil dos surtos epidêmicos de toxi-infecção alimentar produzidos pelo Clostridium perfrigens.

  14. Verification and Validation in Systems Engineering

    CERN Document Server

    Debbabi, Mourad; Jarraya, Yosr; Soeanu, Andrei; Alawneh, Luay

    2010-01-01

    "Verification and validation" represents an important process used for the quality assessment of engineered systems and their compliance with the requirements established at the beginning of or during the development cycle. Debbabi and his coauthors investigate methodologies and techniques that can be employed for the automatic verification and validation of systems engineering design models expressed in standardized modeling languages. Their presentation includes a bird's eye view of the most prominent modeling languages for software and systems engineering, namely the Unified Model

  15. Certifiable Specification and Verification of C Programs

    Science.gov (United States)

    Lüth, Christoph; Walter, Dennis

    A novel approach to the specification and verification of C programs through an annotation language that is a mixture between JML and the language of Isabelle/HOL is proposed. This yields three benefits: specifications are concise and close to the underlying mathematical model; existing Isabelle theories can be reused; and the leap of faith from specification language to encoding in a logic is small. This is of particular relevance for software certification, and verification in application areas such as robotics.

  16. Scalable hardware verification with symbolic simulation

    CERN Document Server

    Bertacco, Valeria

    2006-01-01

    An innovative presentation of the theory of disjoint support decomposition, presenting novel results and algorithms, plus original and up-to-date techniques in formal verificationProvides an overview of current verification techniques, and unveils the inner workings of symbolic simulationFocuses on new techniques that narrow the performance gap between the complexity of digital systems and the limited ability to verify themAddresses key topics in need of future research.

  17. Transmutation Fuel Performance Code Thermal Model Verification

    Energy Technology Data Exchange (ETDEWEB)

    Gregory K. Miller; Pavel G. Medvedev

    2007-09-01

    FRAPCON fuel performance code is being modified to be able to model performance of the nuclear fuels of interest to the Global Nuclear Energy Partnership (GNEP). The present report documents the effort for verification of the FRAPCON thermal model. It was found that, with minor modifications, FRAPCON thermal model temperature calculation agrees with that of the commercial software ABAQUS (Version 6.4-4). This report outlines the methodology of the verification, code input, and calculation results.

  18. An Assembler Driven Verification Methodology (ADVM)

    CERN Document Server

    Macbeth, John S; Gray, Ken

    2011-01-01

    This paper presents an overview of an assembler driven verification methodology (ADVM) that was created and implemented for a chip card project at Infineon Technologies AG. The primary advantage of this methodology is that it enables rapid porting of directed tests to new targets and derivatives, with only a minimum amount of code refactoring. As a consequence, considerable verification development time and effort was saved.

  19. GRIMHX verification and validation summary report

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, R.D.; Toffer, H. [Westinghouse Hanford Co., Richland, WA (United States); Turmble, E.F. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1991-12-01

    As part of the software quality assurance requirements, the reactor analyses codes used for the calculation of key reactor operating and safety parameters require formal verification and validation. The GRIMHX code is used in such applications; this document summarizes the past efforts in this area and combines them with recent new analyses performed by WSRC and Westinghouse Hanford Company (WHC). As such, this document is the most up-to-date compilation of verification and validation information pertaining to the GRIMHX code.

  20. Verification and Examination Management of Complex Systems

    Directory of Open Access Journals (Sweden)

    Stian Ruud

    2014-10-01

    Full Text Available As ship systems become more complex, with an increasing number of safety-critical functions, many interconnected subsystems, tight integration to other systems, and a large amount of potential failure modes, several industry parties have identified the need for improved methods for managing the verification and examination efforts of such complex systems. Such needs are even more prominent now that the marine and offshore industries are targeting more activities and operations in the Arctic environment. In this paper, a set of requirements and a method for verification and examination management are proposed for allocating examination efforts to selected subsystems. The method is based on a definition of a verification risk function for a given system topology and given requirements. The marginal verification risks for the subsystems may then be evaluated, so that examination efforts for the subsystem can be allocated. Two cases of requirements and systems are used to demonstrate the proposed method. The method establishes a systematic relationship between the verification loss, the logic system topology, verification method performance, examination stop criterion, the required examination effort, and a proposed sequence of examinations to reach the examination stop criterion.

  1. Online measurement of the BEPC Ⅱ background using RadFET dosimeters

    Institute of Scientific and Technical Information of China (English)

    GONG Hui; LI Jin; GONG Guang-Hua; LI Yu-Xiong; HOU Lei; SHAO Bei-Bei

    2009-01-01

    To monitor the integral dose deposited in the BESⅢ electromagnetic calorimeter whose perfor-mance degrades due to exposure to the BEPCⅡ background, a 400 nm IMPL RadFET dosimeter-based integral dose online monitor system is built. After calibration with the 60Co source and verification with TLD in the pulse radiation fields, an experiment was arranged to measure the BEPC Ⅱ background online. The results are presented.

  2. Semi-automatic identification of counterfeit offers in online shopping platforms

    OpenAIRE

    Wartner, Christian; Arnold, Patrick; Rahm, Erhard

    2015-01-01

    Product counterfeiting is a serious problem causing the industry estimated losses of billions of dollars every year. With the increasing spread of e-commerce, the number of counterfeit products sold online increased substantially. We propose the adoption of a semi-automatic workflow to identify likely counterfeit offers in online platforms and to present these offers to a domain expert for manual verification. The workflow includes steps to generate search queries for relevant product offers,...

  3. Phase space modulation method for EPID-based Monte Carlo dosimetry of IMRT and RapidArc plans

    Energy Technology Data Exchange (ETDEWEB)

    Berman, Avery; Townson, Reid; Bush, Karl; Zavgorodni, Sergei, E-mail: szavgorodni@bccancer.bc.c

    2010-11-01

    Quality assurance for IMRT and VMAT require 3D evaluation of the dose distributions from the treatment planning system as compared to the distributions reconstructed from signals acquired during the plan delivery. This study presents the results of the dose reconstruction based on a novel method of Monte Carlo (MC) phase space modulation. Typically, in MC dose calculations the linear accelerator (linac) is modelled for each field in the plan and a phase space file (PSF) containing all relevant particle information is written for each field. Particles from the PSFs are then used in the dose calculation. This study investigates a method of omitting the modelling of the linac in cases where the treatment has been measured by an electronic portal imaging device. In this method each portal image is deconvolved using an empirically fit scatter kernel to obtain the primary photon fluence. The Phase Space Modulation (PSM) method consists of simulating the linac just once to create a large PSF for an open field and then modulating it using the delivered primary particle fluence. Reconstructed dose distributions in phantoms were produced using MC and the modulated PSFs. The kernel derived for this method accurately reproduced the dose distributions for 3x3, 10x10, and 15x15 cm{sup 2} field sizes (mean relative dose-difference along the beam central axis is under 1%). The method has been applied to IMRT pre-treatment verification of 10 patients (including one RapidArc{sup TM} case), mean dose in the structures of interest agreed with that calculated by MC directly within 1%, and 95% of the voxels passed 2%/2mm criteria.

  4. Factores de crecimiento IV: Factor de crecimiento epidérmico,Factores estimuladores de colonias, Neurotropinas Growth factors: epidermal growth factor, colony stimulating factors and neurotropins

    Directory of Open Access Journals (Sweden)

    Hilda Norha Jaramillo Londoño

    1999-02-01

    Full Text Available En esta cuarta entrega sobre los factores de crecimiento se revisan el factor de crecimiento epidérmico (EGF, los factores estimuladores de colonias (CSF y las neurotropinas. Como se ha venido presentando en las anteriores entregas, se hace referencia a su estructura bioquímica, su mecanismo de acción, sus efectos biológicos y sus interacciones. Las neurotropinas y el EGF, por tratarse de factores que actúan predominantemente en el microambiente tisular, no pueden manejarse en el contexto de concentraciones circulantes, situación que sí es factible para los CSF. De otro lado, se revisan los mecanismos de las neurotropinas en el sistema nervioso. In this fourth review of growth factors we summarize, as in previous papers, topics related to biochemical structure, mechanisms of action, biological effects and cross-interactions for epidermal growth factor (EGF, colony stimulating factors (CSF and neurotropins. Since the effects of EGF and neurotropins are exerted predominantly at the microenvironment level, they can not be evaluated by means of its circulating levels, a fact that could be possible for CSFs.

  5. Neosporosis epidémica y endémica: descripción de dos eventos en bovinos para cría

    Directory of Open Access Journals (Sweden)

    Patricio M Calandra

    2014-12-01

    Full Text Available El objetivo de este trabajo es describir dos eventos producidos en la provincia de Buenos Aires en los cuales Neospora caninum estuvo asociado a la ocurrencia de abortos en bovinos de cría para carne. En uno de ellos se registraron 11 abortos en 57 vaquillonas durante 45 días, en este evento fue 5 veces más probable que una vaquillona que sufrió un aborto fuera seropositiva a N. caninum que una que no lo sufrió (odds ratio [OR] = 4,9 IC 1,2-19,9 (p 0,05. Se analizaron dos fetos de cada evento: estos resultaron negativos a otros patógenos de la reproducción, aunque presentaron anticuerpos específicos y lesiones histopatológicas compatibles con infecciones por N. caninum. Estos resultados sugieren dos posibles modalidades de presentación de abortos en bovinos causados por N. caninum: una epidémica, como la del primer evento aquí referido, y una endémica, como la del segundo.

  6. Síndrome de Stevens-Johnson e Necrólise Epidérmica Tóxica em um hospital do Distrito Federal

    Directory of Open Access Journals (Sweden)

    Mariane Ferreira Barbosa Emerick

    2014-12-01

    Full Text Available Objetivou-se analisar as características demográficas e clínicas dos clientes diagnosticados com Síndrome de Stevens Johnson (SSJ e Necrólise Epidérmica Tóxica (NET, bem como identificar as ações dos profissionais de saúde para o manejo das Reações Adversas a Medicamentos (RAM em um hospital público do Distrito Federal. Pesquisa descritiva, retrospectiva, com abordagem quantitativa. Dados coletados em todos os prontuários de 22 clientes internados de janeiro de 2005 a setembro de 2012. Análise mediante estatística descritiva. Houve aumento gradativo de casos, com maior número nos anos de 2007 e 2012. Dos casos analisados, 9 foram diagnosticados com NET e 7 com SSJ; predominaram as mulheres (14 e a faixa etária de 21 aos 40 anos (10; 21 obtiveram cura. Os fármacos associados a RAM mais frequentes foram os antiepilépticos (10. Observou-se fragilidade nos registros clínicos nos prontuários e nas ações de monitoramento de RAM no serviço estudado.

  7. Nevo epidérmico inflamatorio lineal (NEVIL: Presentación en la edad adulta Inflammatory linear verrucous epidermal nevus (ILVEN: Late onset disease

    Directory of Open Access Journals (Sweden)

    E J Carbó Amoroso

    2008-06-01

    Full Text Available El NEVIL es la variedad inflamatoria del nevo epidérmico; es un tumor benigno hamartomatoso, que se distribuye siguiendo las líneas de Blaschko. Estas líneas representarían mosaicismos cutáneos del desarrollo embriológico. El NEVIL suele aparecer en la infancia. Son generalmente unilaterales y en ocasiones muy pruriginosos. El diagnóstico diferencial es frecuentemente dificultoso. Presentamos una paciente en la cual la manifestación de esta patología se produce en forma tardía, siendo esto poco frecuente. El tratamiento es un desafío, se han probado múltiples modalidades terapéuticas, con resultados en ocasiones desalentadores. La cirugía, puede utilizarse en lesiones de pequeño tamaño. Los tratamientos con luz láser podrían ser de utilidad.The ILVEN is the inflammatory variety of epidermal nevi, benign hamartomatous tumor that distributed following Blaschko lines. These lines represent cutaneous mosaicism in embryologic development. The ILVEN usually appear in the infancy. Generally unilateral and occasionally is very pruriginous. The differential diagnosis is often difficult. We present a patient in which the manifestation of her disease is produced in late onset, being this infrequent. Management is a challenge, multiple therapeutic modalities have been tested, with discouraging results. Surgery can be utilized in small size lesions. Laser therapy could be of utility.

  8. University Student Online Plagiarism

    Science.gov (United States)

    Wang, Yu-mei

    2008-01-01

    This article reports a study investigating university student online plagiarism. The following questions are investigated: (a) What is the incidence of student online plagiarism? (b) What are student perceptions regarding online plagiarism? (c) Are there any differences in terms of student perceptions of online plagiarism and print plagiarism? (d)…

  9. Online Organic Chemistry

    Science.gov (United States)

    Janowicz, Philip A.

    2010-01-01

    This is a comprehensive study of the many facets of an entirely online organic chemistry course. Online homework with structure-drawing capabilities was found to be more effective than written homework. Online lecture was found to be just as effective as in-person lecture, and students prefer an online lecture format with shorter Webcasts. Online…

  10. University Student Online Plagiarism

    Science.gov (United States)

    Wang, Yu-mei

    2008-01-01

    This article reports a study investigating university student online plagiarism. The following questions are investigated: (a) What is the incidence of student online plagiarism? (b) What are student perceptions regarding online plagiarism? (c) Are there any differences in terms of student perceptions of online plagiarism and print plagiarism? (d)…

  11. Monitoring and verification R&D

    Energy Technology Data Exchange (ETDEWEB)

    Pilat, Joseph F [Los Alamos National Laboratory; Budlong - Sylvester, Kory W [Los Alamos National Laboratory; Fearey, Bryan L [Los Alamos National Laboratory

    2011-01-01

    The 2010 Nuclear Posture Review (NPR) report outlined the Administration's approach to promoting the agenda put forward by President Obama in Prague on April 5, 2009. The NPR calls for a national monitoring and verification R&D program to meet future challenges arising from the Administration's nonproliferation, arms control and disarmament agenda. Verification of a follow-on to New START could have to address warheads and possibly components along with delivery capabilities. Deeper cuts and disarmament would need to address all of these elements along with nuclear weapon testing, nuclear material and weapon production facilities, virtual capabilities from old weapon and existing energy programs and undeclared capabilities. We only know how to address some elements of these challenges today, and the requirements may be more rigorous in the context of deeper cuts as well as disarmament. Moreover, there is a critical need for multiple options to sensitive problems and to address other challenges. There will be other verification challenges in a world of deeper cuts and disarmament, some of which we are already facing. At some point, if the reductions process is progressing, uncertainties about past nuclear materials and weapons production will have to be addressed. IAEA safeguards will need to continue to evolve to meet current and future challenges, and to take advantage of new technologies and approaches. Transparency/verification of nuclear and dual-use exports will also have to be addressed, and there will be a need to make nonproliferation measures more watertight and transparent. In this context, and recognizing we will face all of these challenges even if disarmament is not achieved, this paper will explore possible agreements and arrangements; verification challenges; gaps in monitoring and verification technologies and approaches; and the R&D required to address these gaps and other monitoring and verification challenges.

  12. Attitudes toward buying online.

    Science.gov (United States)

    Yang, Bijou; Lester, David

    2004-02-01

    A survey of 11 positive features and 10 discouraging features of online shopping was carried out on 180 students and identified certain behavioral patterns for online shoppers versus non-shoppers. It was found that online shoppers have consistently stronger positive feelings about online shopping than do non-shoppers. On the other hand, non-shoppers have more negative feelings about online shopping than do shoppers, but not consistently so. Online shoppers are aware of some of the discouraging features of online shopping, but these features do not deter them from shopping online. The implication for marketers is that they should focus on making the experience of online shopping more accommodating and more user-friendly since the positive features of online shopping ("convenience" and "efficiency") appear to be more important than the negative features ("effort/impersonality").

  13. SU-E-P-35: Real-Time Patient Transit Dose Verification of Volumetric Modulated Arc Radiotherapy by a 2D Ionization Chamber Array

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X

    2015-06-15

    Purpose: To explore the real-time dose verification method in volumetric modulated arc radiotherapy (VMAT) with a 2D array ion chamber array. Methods: The 2D ion chamber array was fixed on the panel of electronic portal imaging device (EPID). Source-detector distance (SDD)was 140cm. 8mm RW3 solid water was added to the detector panel to achieve maximum readings.The patient plans for esophageal, prostate and liver cancers were selected to deliver on the cylindrical Cheese phantom 5 times in order to validate the reproducibility of doses. Real-time patient transit dose measurements were performed at each fraction. Dose distributions wereevaluated using gamma index criteria of 3mm DTA and 3% dose difference referred to the firsttime Result. Results: The gamma index pass rate in the Cheese phantom were about 98%; The gamma index pass rate for esophageal, liver and prostate cancer patient were about 92%,94%, and 92%, respectively; Gamma pass rate for all single fraction were more than 90%. Conclusion: The 2D array is capable of monitoring the real time transit doses during VMAT delivery. It is helpful to improve the treatment accuracy.

  14. Online Archives

    Directory of Open Access Journals (Sweden)

    Julian D. Richards

    2004-01-01

    Full Text Available Online archives are of increasing importance in Archaeological Informatics, but like any new genre they prompt a number of questions. What is their relationship to publication? What should go in them? How should they be delivered and indexed? Can they be preserved? Whilst their delivery requires technology, we must also consider how that technology should best be employed in the service of our discipline. This article attempts to address some of these questions but it need not be read from start to finish. The links from this summary provide one fairly linear route through the text but each section is self-contained and can also be accessed directly from the Contents page. The problems posed by effective publication of archaeological fieldwork have exercised the profession for many decades. The issues raised go to the core of discussion of whether preservation by record is a valid concept, and indeed whether archaeological data exist. There are different schools of thought about the relationship between publication and archiving, but hopefully we can accept that data are recorded observations but still agree that they have a re-use value for re-examination and re-interpretation. Since the 1960s archaeology has experienced a publication crisis point. The scenario is familiar. Excavation is destruction; it is an unrepeatable experiment and the archaeologist has a professional obligation to make a full and accessible record of his/her observations. Yet full publication is increasingly expensive and difficult, and excavation monographs are read by few people, and bought by even fewer. In England the development of post-PPG16 fieldwork has exacerbated the problem by creating a mountain of unpublished grey literature and making the work of synthesis even harder; a similar situation exists in other countries. Meanwhile museum archives are also reaching breaking point; most are running out of storage space, few can provide facilities for access, and

  15. Online Shopping Behavior

    OpenAIRE

    Shahzad, Hashim

    2015-01-01

    Online shopping is a very much developed phenomena in Scandinavian countries. Different online factors impact online consumers’ behavior differently depending on the environment of different regions. Sweden is one of the developed and technologically advanced countries. To see the impact of different factors on consumers’ online shopping behavior, the purpose of this study is to analyse the factors that influence consumers’ online shopping behavior in Sweden’s context. One of the objectives o...

  16. Online Marketing Trends

    OpenAIRE

    Horecká, Ivana

    2015-01-01

    This thesis deals with online marketing trends. Its main goal is to define the latest online marketing trends, create a website with the free online marketing trends, and analyse their effectiveness. The theoretical part brings a thorough description of the latest online marketing trends. Moreover, it provides an insight into the latest trends in the website development. The chosen online marketing trends defined in the theoretical part are subsequently applied on a newly created website. All...

  17. Comparing formal verification approaches of interlocking systems

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Nguyen, Hoang Nga; Roggenbach, Markus

    2016-01-01

    The verification of railway interlocking systems is a challenging task, and therefore several research groups have suggested to improve this task by using formal methods, but they use different modelling and verification approaches. To advance this research, there is a need to compare these appro......The verification of railway interlocking systems is a challenging task, and therefore several research groups have suggested to improve this task by using formal methods, but they use different modelling and verification approaches. To advance this research, there is a need to compare...... these approaches. As a first step towards this, in this paper we suggest a way to compare different formal approaches for verifying designs of route-based interlocking systems and we demonstrate it on modelling and verification approaches developed within the research groups at DTU/Bremen and at Surrey....../Swansea. The focus is on designs that are specified by so-called control tables. The paper can serve as a starting point for further comparative studies. The DTU/Bremen research has been funded by the RobustRailS project granted by Innovation Fund Denmark. The Surrey/Swansea research has been funded by the Safe...

  18. VERIFICATION OF PARALLEL AUTOMATA-BASED PROGRAMS

    Directory of Open Access Journals (Sweden)

    M. A. Lukin

    2014-01-01

    Full Text Available The paper deals with an interactive method of automatic verification for parallel automata-based programs. The hierarchical state machines can be implemented in different threads and can interact with each other. Verification is done by means of Spin tool and includes automatic Promela model construction, conversion of LTL-formula to Spin format and counterexamples in terms of automata. Interactive verification gives the possibility to decrease verification time and increase the maximum size of verifiable programs. Considered method supports verification of the parallel system for hierarchical automata that interact with each other through messages and shared variables. The feature of automaton model is that each state machine is considered as a new data type and can have an arbitrary bounded number of instances. Each state machine in the system can run a different state machine in a new thread or have nested state machine. This method was implemented in the developed Stater tool. Stater shows correct operation for all test cases.

  19. Ciphertext verification security of symmetric encryption schemes

    Institute of Scientific and Technical Information of China (English)

    HU ZhenYu; SUN FuChun; JIANG JianChun

    2009-01-01

    This paper formally discusses the security problem caused by the ciphertext verification,presenting a new security notion named IND-CVA (indistinguishability under ciphertext verification attacks) to chap acterize the privacy of encryption schemes in this situation.Allowing the adversary to access to both encryption oracle and ciphertext verification oracle,the new notion IND-CVA is slightly stronger than IND-CPA (indistinguishability under chosen-plaintext attacks) but much weaker than IND-CCA (indistinguishability under chosen-ciphertext attacks),and can be satisfied by most of the popular symmetric encryption schemes such as OTP (one-time-pad),CBC (cipher block chaining) and CTR (counter).An MAC (message authentication scheme) is usually combined with an encryption to guarantee secure communication (e.g.SSH,SSL and IPSec).However,with the notion of IND-CVA,this paper shows that a secure MAC can spoil the privacy in some cases.

  20. The MODUS approach to formal verification

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Soler, José; Berger, Michael Stübert

    2014-01-01

    in the process of providing competitive products Objectives: In relation to this, MODUS (Method and supporting toolset advancing embedded systems quality) project aims to provide small and medium-sized businesses ways to improve their position in the embedded market through a pragmatic and viable solution...... Methods/Approach: This paper will describe the MODUS project with focus on the technical methodologies that can assist formal verification and formal model checking. Results: Based on automated analysis of the characteristics of the system and by controlling the choice of the existing opensource model...... verification engines, model verification producing inputs to be fed into these engines. Conclusions: The MODUS approach is aligned with present market needs; the familiarity with tools, the ease of use and compatibility/interoperability remain among the most important criteria when selecting the development...

  1. CPAchecker: A Tool for Configurable Software Verification

    CERN Document Server

    Beyer, Dirk

    2009-01-01

    Configurable software verification is a recent concept for expressing different program analysis and model checking approaches in one single formalism. This paper presents CPAchecker, a tool and framework that aims at easy integration of new verification components. Every abstract domain, together with the corresponding operations, is required to implement the interface of configurable program analysis (CPA). The main algorithm is configurable to perform a reachability analysis on arbitrary combinations of existing CPAs. The major design goal during the development was to provide a framework for developers that is flexible and easy to extend. We hope that researchers find it convenient and productive to implement new verification ideas and algorithms using this platform and that it advances the field by making it easier to perform practical experiments. The tool is implemented in Java and runs as command-line tool or as Eclipse plug-in. We evaluate the efficiency of our tool on benchmarks from the software mo...

  2. Hierarchical Representation Learning for Kinship Verification.

    Science.gov (United States)

    Kohli, Naman; Vatsa, Mayank; Singh, Richa; Noore, Afzel; Majumdar, Angshul

    2017-01-01

    Kinship verification has a number of applications such as organizing large collections of images and recognizing resemblances among humans. In this paper, first, a human study is conducted to understand the capabilities of human mind and to identify the discriminatory areas of a face that facilitate kinship-cues. The visual stimuli presented to the participants determine their ability to recognize kin relationship using the whole face as well as specific facial regions. The effect of participant gender and age and kin-relation pair of the stimulus is analyzed using quantitative measures such as accuracy, discriminability index d' , and perceptual information entropy. Utilizing the information obtained from the human study, a hierarchical kinship verification via representation learning (KVRL) framework is utilized to learn the representation of different face regions in an unsupervised manner. We propose a novel approach for feature representation termed as filtered contractive deep belief networks (fcDBN). The proposed feature representation encodes relational information present in images using filters and contractive regularization penalty. A compact representation of facial images of kin is extracted as an output from the learned model and a multi-layer neural network is utilized to verify the kin accurately. A new WVU kinship database is created, which consists of multiple images per subject to facilitate kinship verification. The results show that the proposed deep learning framework (KVRL-fcDBN) yields the state-of-the-art kinship verification accuracy on the WVU kinship database and on four existing benchmark data sets. Furthermore, kinship information is used as a soft biometric modality to boost the performance of face verification via product of likelihood ratio and support vector machine based approaches. Using the proposed KVRL-fcDBN framework, an improvement of over 20% is observed in the performance of face verification.

  3. 47 CFR 2.952 - Limitation on verification.

    Science.gov (United States)

    2010-10-01

    ... person shall, in any advertising matter, brochure, etc., use or make reference to a verification in a deceptive or misleading manner or convey the impression that such verification reflects more than a...

  4. A Novel Verification Approach of Workflow Schema

    Institute of Scientific and Technical Information of China (English)

    WANG Guangqi; WANG Juying; WANG Yan; SONG Baoyan; YU Ge

    2006-01-01

    A workflow schema is an abstract description of the business processed by workflow model, and plays a critical role in analyzing, executing and reorganizing business processes. The verification issue on the correctness of complicated workflow schemas is difficult in the field of workflow. We make an intensive study of it in this paper. We present here local errors and schema logic errors (global errors) in workflow schemas in detail, and offer some constraint rules trying to avoid schema errors during modeling. In addition, we propose a verification approach based on graph reduction and graph spread, and give the algorithm. The algorithm is implemented in a workflow prototype system e-ScopeWork.

  5. On Backward-Style Anonymity Verification

    Science.gov (United States)

    Kawabe, Yoshinobu; Mano, Ken; Sakurada, Hideki; Tsukada, Yasuyuki

    Many Internet services and protocols should guarantee anonymity; for example, an electronic voting system should guarantee to prevent the disclosure of who voted for which candidate. To prove trace anonymity, which is an extension of the formulation of anonymity by Schneider and Sidiropoulos, this paper presents an inductive method based on backward anonymous simulations. We show that the existence of an image-finite backward anonymous simulation implies trace anonymity. We also demonstrate the anonymity verification of an e-voting protocol (the FOO protocol) with our backward anonymous simulation technique. When proving the trace anonymity, this paper employs a computer-assisted verification tool based on a theorem prover.

  6. 340 and 310 drawing field verification

    Energy Technology Data Exchange (ETDEWEB)

    Langdon, J.

    1996-09-27

    The purpose of the drawing field verification work plan is to provide reliable drawings for the 310 Treated Effluent Disposal Facility (TEDF) and 340 Waste Handling Facility (340 Facility). The initial scope of this work plan is to provide field verified and updated versions of all the 340 Facility essential drawings. This plan can also be used for field verification of any other drawings that the facility management directs to be so updated. Any drawings revised by this work plan will be issued in an AutoCAD format.

  7. A New Signature Scheme with Shared Verification

    Institute of Scientific and Technical Information of China (English)

    JIA Xiao-yun; LUO Shou-shan; YUAN Chao-wei

    2006-01-01

    With expanding user demands, digital signature techniques are also being expanded greatly, from single signature and single verification techniques to techniques supporting multi-users. This paper presents a new digital signature scheme vith shared verification based on the fiat-shamir signature scheme. This scheme is suitable not only for digital signatures of one public key, but also for situations where multiple public keys are required. In addition, the scheme can resist all kinds of collusion, making it more practicable and safer. Additionally it is more efficient than other schemes.

  8. Differentiation in online retailing

    DEFF Research Database (Denmark)

    Kellner, Julian; Wagner, Gerhard; Zielke, Stephan;

    Due to the highly competitive nature of the online retail environment, differentiation strategies are of importance for online retailers to gain competitive advantages and to achieve a unique positioning in the market. However, little is known about perceptual dimensions used by consumers to make...... a distinction between online retailers. The present study addresses this research gap by using a repertory grid approach to identify points of difference between online retailers from a consumer’s perspective. The results have important implications for positioning strategies of online retailers and research...... on online store formats....

  9. Necrólise epidérmica tóxica secundária ao uso da citosina-arabinosídeo em dose intermediária

    Directory of Open Access Journals (Sweden)

    Figueiredo M.S.

    1998-01-01

    Full Text Available A necrólise epidérmica tóxica é afecção dermatológica secundária ao uso de drogas e corresponde à síndrome de Lyell, relacionada ao eritema multiforme e à síndrome de Stevens-Johnson. OBJETIVOS: Relatar um caso de necrólise epidérmica fatal secundária à citosina-arabinosídeo (Ara-C em dose intermediária. RELATO DE CASO: Paciente do sexo feminino, com 16 anos de idade, portadora de leucemia linfóide aguda - LLA-L1. Iniciou tratamento segundo o protocolo do Grupo Brasileiro de Tratamento da Leucemia Infantil/85, alto risco. Na fase II da indução, após o uso de Ara-C na dose de 1,5g/m², intravenoso, 12/12h x três dias, desenvolveu múltiplas lesões cutâneas bolhosas, que aumentaram rapidamente por progressão das bordas. As bolhas continham secreção serosa, evoluíram para ulceração superficial central, com infecção secundária múltipla. Faleceu por septicemia, no 13º dia após o início do quadro dermatológico. CONCLUSÃO: O Ara-C tem sido relacionado a diversas manifestações de toxicidade dermatológica; no entanto, até o momento, não há relato de necrólise epidérmica tóxica, sendo este o primeiro caso da literatura.

  10. Error diagnóstico en la neuropatía óptica epidémica Diagnostic error in epidemic optic neuropathy

    Directory of Open Access Journals (Sweden)

    Rosaralis Santiesteban Freixas

    2005-12-01

    Full Text Available La forma óptica de la epidemia de neuropatía, aparecida en el decenio pasado en Cuba, ha sido motivo de discusión por el posible hiperdiagnóstico, de los más de 22 000 casos notificados. El propósito principal de este trabajo es profundizar en la caracterización de esta enfermedad y dar a conocer la congruencia que debe de existir entre la agudeza visual y la visión de colores en las neuropatías de este tipo; además, estimar sobre la base de este elemento la posible cifra de errores diagnósticos de dos grupos de pacientes con neuropatía optica epidérmica y en un tercer grupo de pacientes que no mejoraron con tratamiento, donde se reunieron 78 casos remitidos porque no mejoraban con tratamiento vitamínico. Los resultados demostraron congruencia entre el estado de afectación de la agudeza visual y la visión de colores en más del 90 % de los 960 casos de los grupos 1 y 2, con diagnóstico de neuropatía óptica epidémica comprobados por expertos, a diferencia de los casos del tercer grupo, en los que se detectó que el 96,1 % tuvieron de inicio falsos diagnósticos de esta enfermedad p The optic form of the neuropathy epidemic that appeared in the last decade in Cuba has been discussed due to the possible hyperdiagnosis of the more than 22 000 notified cases. The main objective of this paper was to go deep into the characterization of this disease, to make known the congruency that should exist between the visual acuity and the vision of colors in the neuropathies of this type, and to estimate, on the basis of this element, the possible figure of diagnostic errors in 2 groups of patients with EON and of a third group of patients that did not improve with the treatment. In this group, there were 78 cases that were referred because they did not respond to vitamin therapy. The results showed congruency between the state of affection of visual acuity and the vision of colors in more than 90 % of the 960 cases from groups 1 and 2 with

  11. An evaluation of the stability of image-quality parameters of Varian on-board imaging (OBI) and EPID imaging systems.

    Science.gov (United States)

    Stanley, Dennis N; Papanikolaou, Nikos; Gutierrez, Alonso N

    2015-03-08

    Quality assurance (QA) of the image quality for image-guided localization systems is crucial to ensure accurate visualization and localization of regions of interest within the patient. In this study, the temporal stability of selected image parameters was assessed and evaluated for kV CBCT mode, planar radiographic kV, and MV modes. The motivation of the study was to better characterize the temporal variability in specific image-quality parameters. The CATPHAN, QckV-1, and QC-3 phantoms were used to evaluate the image-quality parameters of the imaging systems on a Varian Novalis Tx linear accelerator. The planar radiographic images were analyzed in PIPSpro with high-contrast spatial resolution (f30, f40,f50 lp/mm) being recorded. For OBI kV CBCT, high-quality head full-fan acquisition and pelvis half-fan acquisition modes were evaluated for uniformity, noise, spatial resolution, HU constancy, and geometric distortion. Dose and X-ray energy for the OBI were recorded using the Unfors RaySafe Xi system with the R/F High Detector for kV planar radiographic and the CT detector for kV CBCT. Dose for the MV EPID was recorded using a PTW975 Semiflex ion chamber, PTW UNIDOS electrometer, and CNMC Plastic Water. For each image-quality parameter, values were normalized to the mean, and the normalized standard deviations were recorded to evaluate the parameter's temporal variability. For planar radiographic modes, the normalized standard deviations of the spatial resolution (f30, f40, & f50) were 0.015, 0.008, 0.004 lp/mm and 0.006, 0.009, 0.018 lp/mm for the kV and MV, respectively. The normalized standard deviation of dose for kV and MV were 0.010 mGy and 0.005mGy, respectively. The standard deviations for full- and half-fan kV CBCT modes were averaged together. The following normalized standard deviations for each kV CBCT parameter were: 0.075 HU (uniformity), 0.071 HU (noise), 0.006mm (AP-geometric distortion), 0.005 mm (LAT-geometric distortion), 0.058mm (slice thickness

  12. Surto epidêmico de gastrenterite, com identificação do provável alimento veiculador da infecção

    Directory of Open Access Journals (Sweden)

    Anastácio F. Morgado

    1982-12-01

    Full Text Available Descreve-se um surto epidêmico de gastrenterite entre pessoas adultas, com um total de 52 casos, todos iniciando-se até 24 horas após terem ingerido um alimento provavelmente contaminado. Clinicamente, a doença caracterizou-se por dor abdominal em cólicas, urgência para evacuar, e missão de fezes diarreicas, febre e adinamia, que persistiram por um a tres dias. Todos os casos foram benignos, sem uma só complicação e nenhum tem necessidade de tratamento hospitalar. Foram feitos exames bacteriológicos das fezes de alguns casos, mas não se isolou qualquer germe; esses casos, porém, já estavam em convalescença ou em uso de antibióticos. Todos os casos tinham em comum o fato de terem almoçado ou feito lanche em um mesmo restaurante. Comparou-se, então, 109 pessoas que haviam almoçado, e 70 que haviam feito lanche, com 107 pessoas, do mesmo ambiente dos comensais, que não almoçaram nem lancharam. A associação com fato de almoçar ou lanchar no restaurante foi inequívoca. Ademais, em um número de pessoas bem maior do que os comensais, bebendo da mesma água, não surgiu um só caso de gastroenterite. As 109 pessoas que almoçaram responderam quais os alimentos que haviam ingerido, o que permitiu identificar a carne assada, servida no almoço, como sendo o veiculo provável da infecção. Infelizmente, não se conseguiu restos dessa carne assada para que se pudesse tentar isolar germes. A mediana do período de incubação foi 10,4 horas e os períodos de incubação máximo e mínimo foram de 24 e 0,5 horas, respectivamente; a distribuição cronológica dos casos lembra muito o perfil dos surtos epidêmicos de toxi-infecção alimentar produzidos pelo Clostridium perfrigens.This papes reports an outbreak of gastro-enteritis that occurred in 52 cases after a meai in a local restaurant. The clinical picture was characterised by sudden onset of diarrhea, cramps, nausea and fever (37.5 - 39°C. All cases were mild with in general

  13. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT - PERFORMANCE VERIFICATION OF THE W.L. GORE & ASSOCIATES GORE-SORBER SCREENING SURVEY

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) has created the Environmental Technology Verification Program (ETV) to facilitate the deployment of innovative or improved environmental technologies through performance verification and dissemination of information. The goal of the...

  14. 24 CFR 5.512 - Verification of eligible immigration status.

    Science.gov (United States)

    2010-04-01

    ... immigration status. 5.512 Section 5.512 Housing and Urban Development Office of the Secretary, Department of... Noncitizens § 5.512 Verification of eligible immigration status. (a) General. Except as described in paragraph...) Primary verification—(1) Automated verification system. Primary verification of the immigration status...

  15. 37 CFR 261.6 - Verification of statements of account.

    Science.gov (United States)

    2010-07-01

    ...) General. This section prescribes general rules pertaining to the verification of the statements of account... auditor identified in the notice, and shall be binding on all Designated Agents, and all Copyright Owners.... The Designated Agent requesting the verification procedure shall retain the report of the verification...

  16. 37 CFR 382.5 - Verification of statements of account.

    Science.gov (United States)

    2010-07-01

    ... of account. (a) General. This section prescribes general rules pertaining to the verification of the... the verification procedure shall retain the report of the verification for a period of three years. (e... ordinary course of business according to generally accepted auditing standards by an independent auditor...

  17. 37 CFR 262.7 - Verification of royalty payments.

    Science.gov (United States)

    2010-07-01

    ... Verification of royalty payments. (a) General. This section prescribes procedures by which any Copyright Owner... Designated Agent. Any such audit shall be conducted by an independent and qualified auditor identified in the... verification procedure shall retain the report of the verification for a period of not less than 3 years. (e...

  18. 37 CFR 260.6 - Verification of royalty payments.

    Science.gov (United States)

    2010-07-01

    ... Verification of royalty payments. (a) General. This section prescribes general rules pertaining to the...) Retention of records. The interested party requesting the verification procedure shall retain the report of... generally accepted auditing standards by an independent auditor, shall serve as an acceptable verification...

  19. 37 CFR 384.7 - Verification of royalty distributions.

    Science.gov (United States)

    2010-07-01

    ... BUSINESS ESTABLISHMENT SERVICES § 384.7 Verification of royalty distributions. (a) General. This section.... Any such audit shall be conducted by an independent and Qualified Auditor identified in the notice... report of the verification for a period of not less than 3 years. (e) Acceptable verification procedure...

  20. Probabilistic Verification of Multi-Robot Missions in Uncertain Environments

    Science.gov (United States)

    2015-11-01

    uncertain environment. Verification of robot software is related to general purpose software verification in its objective of taking a program as...input and automatically determining whether that program achieves a desired objective or not [1]. It differs in that a robot program continually...Probabilistic Verification of Multi -Robot Missions in Uncertain Environments Damian M. Lyons*, Ronald C. Arkin‡, Shu Jiang‡, Dagan Harrington

  1. The Construction of Verification Models for Embedded Systems

    NARCIS (Netherlands)

    Mader, Angelika H.; Wupper, H.; Boon, Mieke

    2007-01-01

    The usefulness of verification hinges on the quality of the verification model. Verification is useful if it increases our confidence that an artefact bahaves as expected. As modelling inherently contains non-formal elements, the qualityof models cannot be captured by purely formal means. Still, we

  2. Secure Batch Verification Protocol for RSA Signature Scheme

    Institute of Scientific and Technical Information of China (English)

    JIAZongpu; LIQingchao; LIZichen

    2005-01-01

    Harn, in 1998, proposed an efficient batch verification scheme for multiple RSA digital signatures.However, the scheme has a weakness, that is a signer can generate multiple signatures which can pass the batch verification scheme, but every one of these multiple signatures is not a valid signature. To avoid this disadvantage, we propose an improved batch verification scheme.

  3. Dengue: inquérito sorológico pós-epidêmico em zona urbana do Estado de São Paulo (Brasil

    Directory of Open Access Journals (Sweden)

    Virgília L C de Lima

    1999-12-01

    Full Text Available OBJETIVO: Avaliar o tamanho real da epidemia sobre dengue ocorrida na zona urbana do Município de Santa Bárbara D'Oeste, SP, Brasil, de abril a junho de 1995. MÉTODOS: Foi realizado um inquérito soroepidemiológico pós-epidêmico 5 meses após o final da epidemia da dengue. Foram processados 1.113 soros através de amostragem aleatória domiciliar da população da cidade pesquisada. As taxas de infecção em diferentes partes da cidade foram relacionadas com os graus de infestação por Aedes aegipty e com a quantidade de casos notificados durante a epidemia. RESULTADOS E CONCLUSÕES: Foi encontrada variação concomitante e diretamente proporcional entre as taxas de infecção pelo vírus da dengue, em diferentes partes da cidade, e os graus de infestação domiciliar por Aedes aegipty, bem como em relação ao número de casos notificados durante a epidemia. Encontrou-se prevalência de 630 por 100 mil habitantes, representando valor 15 vezes superior ao de incidência de casos confirmados laboratorialmente durante a epidemia. Através de comparação retrospectiva com dados de notificação compulsória, observou-se que a vigilância epidemiológica não detectou a maioria das pessoas soro-reativas. Apesar disso, notificou grande quantidade de casos que não eram de indivíduos com dengue, tipificando um valor preditivo positivo baixo (15,6% para o diagnóstico clínico de dengue quando o resultado laboratorial (HAI é tomado como padrão-ouro.

  4. Dengue: inquérito sorológico pós-epidêmico em zona urbana do Estado de São Paulo (Brasil

    Directory of Open Access Journals (Sweden)

    Lima Virgília L C de

    1999-01-01

    Full Text Available OBJETIVO: Avaliar o tamanho real da epidemia sobre dengue ocorrida na zona urbana do Município de Santa Bárbara D'Oeste, SP, Brasil, de abril a junho de 1995. MÉTODOS: Foi realizado um inquérito soroepidemiológico pós-epidêmico 5 meses após o final da epidemia da dengue. Foram processados 1.113 soros através de amostragem aleatória domiciliar da população da cidade pesquisada. As taxas de infecção em diferentes partes da cidade foram relacionadas com os graus de infestação por Aedes aegipty e com a quantidade de casos notificados durante a epidemia. RESULTADOS E CONCLUSÕES: Foi encontrada variação concomitante e diretamente proporcional entre as taxas de infecção pelo vírus da dengue, em diferentes partes da cidade, e os graus de infestação domiciliar por Aedes aegipty, bem como em relação ao número de casos notificados durante a epidemia. Encontrou-se prevalência de 630 por 100 mil habitantes, representando valor 15 vezes superior ao de incidência de casos confirmados laboratorialmente durante a epidemia. Através de comparação retrospectiva com dados de notificação compulsória, observou-se que a vigilância epidemiológica não detectou a maioria das pessoas soro-reativas. Apesar disso, notificou grande quantidade de casos que não eram de indivíduos com dengue, tipificando um valor preditivo positivo baixo (15,6% para o diagnóstico clínico de dengue quando o resultado laboratorial (HAI é tomado como padrão-ouro.

  5. Perspectivas de salud ambiental en la investigación de brotes epidémicos asociados con una zona de abastecimiento de aguas de consumo humano

    Directory of Open Access Journals (Sweden)

    Joaquín Gámez de la Hoz

    2004-12-01

    Full Text Available Introducción. El propósito de este trabajo fue estudiar la magnitud, posibles causas y factores ambientales contribuyentes en la aparición de brotes de origen hídrico, en el ámbito de actuación de la localidad de Benaoján (Serranía de Ronda, Málaga.Material y métodos. Análisis de la potabilidad del agua y controles de desinfección. Evaluación del cumplimiento de la calidad del agua potable y requisitos técnico sanitarios de abastecimientos de aguas, conforme a la normativa española sobre aguas de consumo público.Resultados. Se han realizado 110 análisis de potabilidad, comprobando que el 13,4% de las muestras no cumplen con los criterios de potabilidad del agua. Se practicaron 647 controles de desinfección, de los que el 53% resultaron no conformes. El diseño de la red de abastecimiento es del tipo ramificada y al menos presenta 30 ramales ciegos, puntos donde el agua queda estancada. El servicio municipal de aguas no realiza autocontroles de la calidad del agua ni tiene implantados planes generales de higiene de las instalaciones del abastecimiento.Discusión. La investigación ambiental sugiere que la red pública de abastecimiento de aguas es una fuente de infección, problema relacionado con la aparición de brotes epidémicos. Por ello el consumo de agua no tratada debe ser evitado.

  6. Acción del factor de crecimiento epidérmico sobre el desarrollo de las células estriatales cultivadas

    Directory of Open Access Journals (Sweden)

    Lázara Castillo

    1996-06-01

    Full Text Available En este trabajo se describe la acción del factor de crecimiento epidérmico (FCE sobre las células del estriado embrionario en un sistema de cultivo disociado de neuronas y glías. El cultivo de células se preparó a partir de embriones de ratas de 16-17 días. En el sistema de cultivo empleado, la población celular fue cultivada durante 20-24 horas en un medio que contenía suero y, posteriormente, fue tratada con 20 ng/mL del FCE en un medio libre de suero. La eliminación del suero en este período inicial de desarrollo provocó una disminución apreciable de las células vivas en los cultivos tratados y en los controles. Al parecer, la población de células sobrevivientes estaba integrada, en su mayoría, por precursores celulares teniendo en cuenta su capacidad proliferativa. La acción del FCE sobre las células se manifestó en un aumento del número de células debido fundamentalmente a un estímulo de la proliferación de los precursores neuronales y astrocitos. Este efecto estuvo acompañado por una reducción de la diferenciación morfológica neuronal cuando se comparó con los cultivos controles. En los cultivos, a los 16 días, la detección de la actividad específica de la colina acetiltrasferasa evidenció la diferenciación de una subpoblación neuronal colinérgica, las cuales respondieron al tratamiento con el factor de crecimiento nervioso con un aumento de la actividad de la enzima.

  7. Uso de membrana amniótica en el manejo oftalmológico agudo de la necrólisis epidérmica tóxica: presentación de caso

    OpenAIRE

    Plazola Hernández, Sara Isabel; Hernández Martínez, Natalia

    2016-01-01

    El síndrome de Stevens-Johnson y la necrólisis epidérmica tóxica (NET) son enfermedades raras, agudas y exfoliativas que afectan la piel y membranas mucosas. Se producen como una reacción de hipersensibilidad a diferentes agentes farmacológicos o infecciosos. Hasta un 69-81% de los pacientes con síndrome de Stevens-Johnson y un 50-67% de los pacientes con NET presentan afectación ocular. Las manifestaciones oculares agudas se caracterizan por una conjuntivitis seudomembranosa o membrano...

  8. The Online Underworld.

    Science.gov (United States)

    Scrogan, Len

    1988-01-01

    Discusses some of the misuses of telecommunicating using school computers, including online piracy, hacking, phreaking, online crime, and destruction boards. Suggests ways that schools can deal with these problems. (TW)

  9. The COST IC0701 verification competition 2011

    NARCIS (Netherlands)

    Bormer, T.; Brockschmidt, M.; Distefano, D.; Ernst, G.; Filliatre, J.-C.; Grigore, R.; Huisman, M.; Klebanov, V.; Marche, C.; Monahan, R.; Mostowski, W.I.; Poiikarpova, N.; Scheben, C.; Schellhorn, G.; Tofan, B.; Tschannen, J.; Ulbrich, M.; Beckert, B.; Damiani, F.; Gurov, D.

    2012-01-01

    This paper reports on the experiences with the program verification competition held during the FoVeOOS conference in October 2011. There were 6 teams participating in this competition. We discuss the three different challenges that were posed and the solutions developed by the teams. We conclude wi

  10. Using timing information in speaker verification

    CSIR Research Space (South Africa)

    Van Heerden, CJ

    2005-11-01

    Full Text Available This paper presents an analysis of temporal information as a feature for use in speaker verification systems. The relevance of temporal information in a speaker’s utterances is investigated, both with regard to improving the robustness of modern...

  11. RELAP-7 SOFTWARE VERIFICATION AND VALIDATION PLAN

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Curtis L [Idaho National Laboratory; Choi, Yong-Joon [Idaho National Laboratory; Zou, Ling [Idaho National Laboratory

    2014-09-01

    This INL plan comprehensively describes the software for RELAP-7 and documents the software, interface, and software design requirements for the application. The plan also describes the testing-based software verification and validation (SV&V) process—a set of specially designed software models used to test RELAP-7.

  12. 9 CFR 417.8 - Agency verification.

    Science.gov (United States)

    2010-01-01

    ... REGULATORY REQUIREMENTS UNDER THE FEDERAL MEAT INSPECTION ACT AND THE POULTRY PRODUCTS INSPECTION ACT HAZARD ANALYSIS AND CRITICAL CONTROL POINT (HACCP) SYSTEMS § 417.8 Agency verification. FSIS will verify the adequacy of the HACCP plan(s) by determining that each HACCP plan meets the requirements of this part...

  13. Resource Protection Using Atomics: Patterns and Verification

    NARCIS (Netherlands)

    Amighi, A.; Blom, Stefan; Huisman, Marieke; Garrigue, Jacques

    For the verification of concurrent programs, it is essential to be able to show that synchronisation mechanisms are implemented correctly. A common way to implement such sychronisers is by using atomic operations. This paper identifies what different synchronisation patterns can be implemented by

  14. 16 CFR 315.5 - Prescriber verification.

    Science.gov (United States)

    2010-01-01

    ... time of verification request; (6) The name of a contact person at the seller's company, including... that the same company manufactures and sells under different labels. (f) Recordkeeping requirement... digital image of the prescription), that was presented to the seller by the patient or prescriber. (2)...

  15. ENROLMENT MODEL STABILITY IN STATIC SIGNATURE VERIFICATION

    NARCIS (Netherlands)

    Allgrove, C.; Fairhurst, M.C.

    2004-01-01

    The stability of enrolment models used in a static verification system is assessed, in order to provide an enhanced chracterisation of signatures through the validation of the enrolment process. A number of static features are used to illustrate the effect of the variation in enrolment model size on

  16. Implementing Online Physical Education

    Science.gov (United States)

    Mohnsen, Bonnie

    2012-01-01

    Online physical education, although seemingly an oxymoron, appears to be the wave of the future at least for some students. The purpose of this article is to explore research and options for online learning in physical education and to examine a curriculum, assessment, and instructional model for online learning. The article examines how physical…

  17. Performance marketing online

    OpenAIRE

    Hamaďáková, Markéta

    2012-01-01

    This thesis discusses the online performance marketing business practices. The theoretical part contains the definition of performance marketing and presents its main components, which include the key performance indicators, the targeting of users, the pricing models of online advertising and affiliate marketing. The second part of the thesis analyzes the performance of online marketing operations for the website FFFFLASH.com.

  18. Connecting to On-line Data

    Science.gov (United States)

    Eichhorn, G.; Astrophysics Datacenter Executive Committee (ADEC)

    2004-05-01

    The Astrophysics Datacenter Executive Committee (ADEC) is coordinating the development of a system to facilitate the linking to on-line data. This system has three components: 1. Unique dataset identifiers. 2. A verification system for identifiers. 3. Permanent links to on-line data sets. 1. The ADEC has agreed on a naming scheme for data sets that allows for the unique identification of any data set. The ADEC data centers will clearly mark their data with these identifiers to allow the generation of links to these data. 2. Each data center has a utility that can check whether a data set identifier is a valid identifier at that center. A central verifier allows third parties access to these individual verifiers through a single portal. 3. The central verifier also provides permanent links to data sets through a central link forwarding system. This makes it possible to move data sets between data centers while maintaining the permanent links. The ADEC plans to first use this system to implement the linking from the literature to on-line data in a collaboration with the AAS and the University of Chicago Press for the AAS journals.

  19. On the role of code comparisons in verification and validation.

    Energy Technology Data Exchange (ETDEWEB)

    Oberkampf, William Louis; Trucano, Timothy Guy; Pilch, Martin M.

    2003-08-01

    This report presents a perspective on the role of code comparison activities in verification and validation. We formally define the act of code comparison as the Code Comparison Principle (CCP) and investigate its application in both verification and validation. One of our primary conclusions is that the use of code comparisons for validation is improper and dangerous. We also conclude that while code comparisons may be argued to provide a beneficial component in code verification activities, there are higher quality code verification tasks that should take precedence. Finally, we provide a process for application of the CCP that we believe is minimal for achieving benefit in verification processes.

  20. Runtime verification of embedded real-time systems.

    Science.gov (United States)

    Reinbacher, Thomas; Függer, Matthias; Brauer, Jörg

    We present a runtime verification framework that allows on-line monitoring of past-time Metric Temporal Logic (ptMTL) specifications in a discrete time setting. We design observer algorithms for the time-bounded modalities of ptMTL, which take advantage of the highly parallel nature of hardware designs. The algorithms can be translated into efficient hardware blocks, which are designed for reconfigurability, thus, facilitate applications of the framework in both a prototyping and a post-deployment phase of embedded real-time systems. We provide formal correctness proofs for all presented observer algorithms and analyze their time and space complexity. For example, for the most general operator considered, the time-bounded Since operator, we obtain a time complexity that is doubly logarithmic both in the point in time the operator is executed and the operator's time bounds. This result is promising with respect to a self-contained, non-interfering monitoring approach that evaluates real-time specifications in parallel to the system-under-test. We implement our framework on a Field Programmable Gate Array platform and use extensive simulation and logic synthesis runs to assess the benefits of the approach in terms of resource usage and operating frequency.

  1. Utterance Verification for Text-Dependent Speaker Recognition

    DEFF Research Database (Denmark)

    Kinnunen, Tomi; Sahidullah, Md; Kukanov, Ivan

    2016-01-01

    Text-dependent automatic speaker verification naturally calls for the simultaneous verification of speaker identity and spoken content. These two tasks can be achieved with automatic speaker verification (ASV) and utterance verification (UV) technologies. While both have been addressed previously...... in the literature, a treatment of simultaneous speaker and utterance verification with a modern, standard database is so far lacking. This is despite the burgeoning demand for voice biometrics in a plethora of practical security applications. With the goal of improving overall verification performance, this paper...... reports different strategies for simultaneous ASV and UV in the context of short-duration, text-dependent speaker verification. Experiments performed on the recently released RedDots corpus are reported for three different ASV systems and four different UV systems. Results show that the combination...

  2. Online Cake Cutting

    CERN Document Server

    Walsh, Toby

    2010-01-01

    We propose an online form of the cake cutting problem. This models situations where players arrive and depart during the process of dividing a resource. We show that well known fair division procedures like cut-and-choose and the Dubins-Spanier moving knife procedure can be adapted to apply to such online problems. We propose some desirable properties that online cake cutting procedures might possess like online forms of proportionality and envy-freeness, and identify which properties are in fact possessed by the different online cake procedures.

  3. Differentiation in online retailing

    DEFF Research Database (Denmark)

    Kellner, Julian; Wagner, Gerhard; Zielke, Stephan

    Due to the highly competitive nature of the online retail environment, differentiation strategies are of importance for online retailers to gain competitive advantages and to achieve a unique positioning in the market. However, little is known about perceptual dimensions used by consumers to make...... a distinction between online retailers. The present study addresses this research gap by using a repertory grid approach to identify points of difference between online retailers from a consumer’s perspective. The results have important implications for positioning strategies of online retailers and research...

  4. Density of primary and secondary epidermal laminae of equine hoof Densidade das lâminas epidérmicas primárias e secundárias nos cascos de equinos

    Directory of Open Access Journals (Sweden)

    André R.C. Barreto-Vianna

    2013-04-01

    Full Text Available Differences in the microscopic morphology of the hoof in forelimbs and hindlimbs of horses have been scarcely reported in the literature, especially concerning the distribution of primary and secondary epidermal laminae in the different regions. This study aimed to determine the density of primary and secondary epidermal laminae in the hoof of horses. For this, it was used fore and hindlimbs of 16 adult mixed breed horses. With a cross section 0.5 cm above the sole, it was quantified the primary epidermal laminae in the regions of the toe, and of lateral and medial quarters. Fragments with about 1cm ³ were taken from the proximal, middle and distal thirds of the hooves, in the different regions, subjected to conventional histological techniques and examined with an optical microscope. Data were statistically analyzed in relation to the fore and hindlimbs and between their various regions. The density of primary epidermal laminae varied around the hoof circumference, with greater values in the hoof toe, which gradually decreased towards the bulb of the hoof, without difference between thoracic and pelvic limbs. The average density of the secondary epidermal laminae per primary epidermal lamina does not change around the circumference of the hoof. Our findings indicated that the density of epidermal laminae is not different between fore and hindlimbs. The variation in the density of primary epidermal laminae around the hoof seems to be part of an adaptive response to different stresses in each region. A better understanding of the structural morphology contributes to a better understanding of the diagnosis, pathophysiology, and treatment of disorders that affect the hoof.Diferenças na morfologia microscópica dos cascos dos membros pélvicos e torácicos dos equinos têm sido pouco relatadas na literatura, principalmente no tocante a distribuição de lâminas epidérmicas primárias e secundárias nas diversas regiões. O propósito deste

  5. Applications of a hologram watermarking protocol: aging-aware biometric signature verification and time validity check with personal documents

    Science.gov (United States)

    Vielhauer, Claus; Croce Ferri, Lucilla

    2003-06-01

    Our paper addresses two issues of a biometric authentication algorithm for ID cardholders previously presented namely the security of the embedded reference data and the aging process of the biometric data. We describe a protocol that allows two levels of verification, combining a biometric hash technique based on handwritten signature and hologram watermarks with cryptographic signatures in a verification infrastructure. This infrastructure consists of a Trusted Central Public Authority (TCPA), which serves numerous Enrollment Stations (ES) in a secure environment. Each individual performs an enrollment at an ES, which provides the TCPA with the full biometric reference data and a document hash. The TCPA then calculates the authentication record (AR) with the biometric hash, a validity timestamp, and a document hash provided by the ES. The AR is then signed with a cryptographic signature function, initialized with the TCPA's private key and embedded in the ID card as a watermark. Authentication is performed at Verification Stations (VS), where the ID card will be scanned and the signed AR is retrieved from the watermark. Due to the timestamp mechanism and a two level biometric verification technique based on offline and online features, the AR can deal with the aging process of the biometric feature by forcing a re-enrollment of the user after expiry, making use of the ES infrastructure. We describe some attack scenarios and we illustrate the watermarking embedding, retrieval and dispute protocols, analyzing their requisites, advantages and disadvantages in relation to security requirements.

  6. Verifying Functions in Online Stock Trading Systems

    Institute of Scientific and Technical Information of China (English)

    Yu-Yue Du; Chang-Jun Jiang

    2004-01-01

    Temporal colored Petri nets, an extension of temporal Petri nets, are introduced in this paper. It can distinguish the personality of individuals (tokens), describe clearly the causal and temporal relationships between events in concurrent systems, and represent elegantly certain fundamental properties of concurrent systems,such as eventuality and fairness. The use of this method is illustrated with an example of modeling and formal verification of an online stock trading system. The functional correctness of the modeled system is formally verified based on the temporal colored Petri net model and temporal assertions. Also, some main properties of the system are analyzed. It has been demonstrated sufficiently that temporal colored Petri nets can verify efficiently some time-related properties of concurrent systems, and provide both the power of dynamic representation graphically and the function of logical inference formally. Finally, future work is described.

  7. Enabling Automatic Certification of Online Auctions

    Directory of Open Access Journals (Sweden)

    Wei Bai

    2014-04-01

    Full Text Available We consider the problem of building up trust in a network of online auctions by software agents. This requires agents to have a deeper understanding of auction mechanisms and be able to verify desirable properties of a given mechanism. We have shown how these mechanisms can be formalised as semantic web services in OWL-S, a good enough expressive machine-readable formalism enabling software agents, to discover, invoke, and execute a web service. We have also used abstract interpretation to translate the auction's specifications from OWL-S, based on description logic, to COQ, based on typed lambda calculus, in order to enable automatic verification of desirable properties of the auction by the software agents. For this language translation, we have discussed the syntactic transformation as well as the semantics connections between both concrete and abstract domains. This work contributes to the implementation of the vision of agent-mediated e-commerce systems.

  8. Quantification, Prediction, and the Online Impact of Sentence Truth-Value: Evidence from Event-Related Potentials

    Science.gov (United States)

    Nieuwland, Mante S.

    2016-01-01

    Do negative quantifiers like "few" reduce people's ability to rapidly evaluate incoming language with respect to world knowledge? Previous research has addressed this question by examining whether online measures of quantifier comprehension match the "final" interpretation reflected in verification judgments. However, these…

  9. SU-E-T-379: Evaluation of An EPID-Based System for Daily Dosimetry Check by Comparison with a Widely-Used Ionization Chamber-Based Device

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, D; Koch, N; Peng, J; Jacqmin, D; Ashenafi, M; Vanek, K [Medical University of South Carolina, Charleston, SC (United States)

    2015-06-15

    Purpose: To examine the feasibility of using Varian’s EPID-based Machine Performance Check (MPC) system to track daily machine output through comparison with Sun Nuclear’s DailyQA3 (DQA) device. Methods: Daily machine outputs for two photon energies (6 and 16MV) and five electron energies (6, 9, 12, 16, 20MeV) were measured for one month using both MPC and DQA. Baselines measurements for MPC were taken at the start of the measurement series, while DQA baselines were set at an earlier date. In order to make absolute comparisons with MPC, all DQA readings were referenced to the average of the first three DQA readings in that series, minimizing systematic differences between the measurement techniques due to baseline differences. In addition to daily output measurements, weekly averages were also calculated and compared. Finally, the electron energy dependence of each measurement technique was examined by comparing energy-specific measurements to the average electron output of all energies each day. Results: For 6 and 16MV photons, the largest absolute percent differences between MPC and DQA were 0.60% and 0.73%, respectively. Weekly averages were within 0.17% and 0.23%, respectively. For all five electron energies, the greatest absolute percent differences between MPC and DQA for each energy ranged from 0.49%–0.83%. Weekly averages ranged from 0.07%–0.28%. DQA energy-specific electron readings matched the average electron output within 0.29% for all days and all energies. MPC energy-specific readings matched the average within 0.21% for 9–20MeV. However, 6MeV showed a larger distribution about the average with four days showing a difference greater than 0.30% and a maximum difference of 0.51%. Conclusion: MPC output measurements correlated well with the widely-used DQA3 for most beam energies, making it a reliable back up technique for daily output monitoring. However, MPC may display an energy dependence for lower electrons energies, requiring additional

  10. Detección del receptor tipo 2 del factor de crecimiento epidérmico humano (her2/neu: inmunohistoquímica en carcinomas de mama

    Directory of Open Access Journals (Sweden)

    José Luis Quirós-Alpízar

    2015-03-01

    Full Text Available Antecedentes: la incidencia y mortalidad por cáncer de mama han presentado un aumento neto. Uno de los tipos de esta heterogénea enfermedad se caracteriza por la amplificación y alta expresión del gen ERBB2, que codifica el receptor tipo 2 del factor de crecimiento epidérmico humano (HER2. Este receptor estimula procesos oncogénicos y dichos tumores se asocian a un peor pronóstico. El objetivo del estudio fue analizar las características de tumores HER-2+ en un grupo de pacientes con carcinoma de mama. Métodos: se estudió los casos de mujeres con biopsia diagnóstica de cáncer de mama registrados durante 2006 en los archivos del Servicio de Anatomía Patológica del Hospital San Juan de Dios; entre los que contaban con estudios inmunohistoquímicos, se estudió la expresión de HER-2 y se realizó análisis estadísticos. Resultados: se halló 34 tumores HER-2+ (15,7%, 24 con expresión fuerte (11,1% y 10 con débil (4,6%. La edad media al diagnóstico de las pacientes con expresión fuerte fue de 46,9 años (42,5-51,1 IC 95%, y con expresión débil fue de 54,4 años (46,7-62,1 IC 95%; la edad promedio para los tumores HER-2- fue de 58,1 años (56,2-60,0 IC 95%. Las pacientes <50 años tuvieron un OR=3,477 de tener HER-2+. De 21 tumores, el 90,5% presentó un grado histológico alto, y de 16 casos, únicamente 3 tenían un tamaño <2 cm. Conclusión: se encontró una asociación del tipo HER-2+ con pacientes jóvenes, tumores de mayor tamaño y alto grado histológico. Los datos encontrados en este primer reporte son similares a las últimas estimaciones mundiales.

  11. Automated Formal Verification for PLC Control Systems

    CERN Multimedia

    Fernández Adiego, Borja

    2014-01-01

    Programmable Logic Controllers (PLCs) are widely used devices used in industrial control systems. Ensuring that the PLC software is compliant with its specification is a challenging task. Formal verification has become a recommended practice to ensure the correctness of the safety-critical software. However, these techniques are still not widely applied in industry due to the complexity of building formal models, which represent the system and the formalization of requirement specifications. We propose a general methodology to perform automated model checking of complex properties expressed in temporal logics (e.g. CTL, LTL) on PLC programs. This methodology is based on an Intermediate Model (IM), meant to transform PLC programs written in any of the languages described in the IEC 61131-3 standard (ST, IL, etc.) to different modeling languages of verification tools. This approach has been applied to CERN PLC programs validating the methodology.

  12. Systems Approach to Arms Control Verification

    Energy Technology Data Exchange (ETDEWEB)

    Allen, K; Neimeyer, I; Listner, C; Stein, G; Chen, C; Dreicer, M

    2015-05-15

    Using the decades of experience of developing concepts and technologies for verifying bilateral and multilateral arms control agreements, a broad conceptual systems approach is being developed that takes into account varying levels of information and risk. The IAEA has already demonstrated the applicability of a systems approach by implementing safeguards at the State level, with acquisition path analysis as the key element. In order to test whether such an approach could also be implemented for arms control verification, an exercise was conducted in November 2014 at the JRC ITU Ispra. Based on the scenario of a hypothetical treaty between two model nuclear weapons states aimed at capping their nuclear arsenals at existing levels, the goal of this exercise was to explore how to use acquisition path analysis in an arms control context. Our contribution will present the scenario, objectives and results of this exercise, and attempt to define future workshops aimed at further developing verification measures that will deter or detect treaty violations.

  13. Verificator: Educational Tool for Learning Programming

    Directory of Open Access Journals (Sweden)

    Danijel RADOSEVIC

    2009-09-01

    Full Text Available The paper introduces Verificator, our learning programming interface aimed for learningprogramming in C++ at the university beginners’ level. In teaching programming some specificproblems concerning the teaching itself as well as the organization of the teaching process need tobe considered. One of the biggest problems is that students tend to adopt certain bad programminghabits in their attempt to more easily deal with their examinations, such as trying to write programswithout any syntax and logical checking. It is very hard to help them correct those errors once theyare deeply rooted. Our students’ web questionnaire and its results show that the majority of problemsin learning programming among our students arise from the gap between the understanding ofprogramming language syntax and problem-solving algorithms. Verificator prevents students frommaking a lot of errors they are likely to make in learning programming and helps them to learnprogramming language syntax and adopt good programming habits.

  14. Extensible Technology-Agnostic Runtime Verification

    Directory of Open Access Journals (Sweden)

    Christian Colombo

    2013-02-01

    Full Text Available With numerous specialised technologies available to industry, it has become increasingly frequent for computer systems to be composed of heterogeneous components built over, and using, different technologies and languages. While this enables developers to use the appropriate technologies for specific contexts, it becomes more challenging to ensure the correctness of the overall system. In this paper we propose a framework to enable extensible technology agnostic runtime verification and we present an extension of polyLarva, a runtime-verification tool able to handle the monitoring of heterogeneous-component systems. The approach is then applied to a case study of a component-based artefact using different technologies, namely C and Java.

  15. Verification of Tolerance Chains in Micro Manufacturing

    DEFF Research Database (Denmark)

    Gasparin, Stefania

    The aim of this work is to define methodologies for the tolerance verification of injection moulded components with downscaled dimensions. In micro and nano metrology different challenges can be found: lack of calibration artefacts and available ISO standards, problematic uncertainty budget...... on a calibrated standard artefact and to measure both in order to assure an unbroken chain of comparisons. The replica technique reveals to be a fast, cost-effective and reliable method. Regarding the tolerance verification of micro parts and nano-structured surfaces, a systematic approach is discussed based...... on dimensional and geometrical metrology. If the measurements uncertainty is large compared to the tolerance interval, a small conformance zone is left for process variation. Therefore particular attention has to be paid to the instrument capabilities in order to reduce the measurement uncertainty. Different...

  16. Spatial Verification Using Wavelet Transforms: A Review

    CERN Document Server

    Weniger, Michael; Friederichs, Petra

    2016-01-01

    Due to the emergence of new high resolution numerical weather prediction (NWP) models and the availability of new or more reliable remote sensing data, the importance of efficient spatial verification techniques is growing. Wavelet transforms offer an effective framework to decompose spatial data into separate (and possibly orthogonal) scales and directions. Most wavelet based spatial verification techniques have been developed or refined in the last decade and concentrate on assessing forecast performance (i.e. forecast skill or forecast error) on distinct physical scales. Particularly during the last five years, a significant growth in meteorological applications could be observed. However, a comparison with other scientific fields such as feature detection, image fusion, texture analysis, or facial and biometric recognition, shows that there is still a considerable, currently unused potential to derive useful diagnostic information. In order to tab the full potential of wavelet analysis, we revise the stat...

  17. Formal Verification, Engineering and Business Value

    Directory of Open Access Journals (Sweden)

    Ralf Huuck

    2012-12-01

    Full Text Available How to apply automated verification technology such as model checking and static program analysis to millions of lines of embedded C/C++ code? How to package this technology in a way that it can be used by software developers and engineers, who might have no background in formal verification? And how to convince business managers to actually pay for such a software? This work addresses a number of those questions. Based on our own experience on developing and distributing the Goanna source code analyzer for detecting software bugs and security vulnerabilities in C/C++ code, we explain the underlying technology of model checking, static analysis and SMT solving, steps involved in creating industrial-proof tools.

  18. Packaged low-level waste verification system

    Energy Technology Data Exchange (ETDEWEB)

    Tuite, K.; Winberg, M.R.; McIsaac, C.V. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-12-31

    The Department of Energy through the National Low-Level Waste Management Program and WMG Inc. have entered into a joint development effort to design, build, and demonstrate the Packaged Low-Level Waste Verification System. Currently, states and low-level radioactive waste disposal site operators have no method to independently verify the radionuclide content of packaged low-level waste that arrives at disposal sites for disposition. At this time, the disposal site relies on the low-level waste generator shipping manifests and accompanying records to ensure that low-level waste received meets the site`s waste acceptance criteria. The subject invention provides the equipment, software, and methods to enable the independent verification of low-level waste shipping records to ensure that the site`s waste acceptance criteria are being met. The objective of the prototype system is to demonstrate a mobile system capable of independently verifying the content of packaged low-level waste.

  19. Formal verification of industrial control systems

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Verification of critical software is a high priority but a challenging task for industrial control systems. For many kinds of problems, testing is not an efficient method. Formal methods, such as model checking appears to be an appropriate complementary method. However, it is not common to use model checking in industry yet, as this method needs typically formal methods expertise and huge computing power. In the EN-ICE-PLC section, we are working on a [methodology][1] and a tool ([PLCverif][2]) to overcome these challenges and to integrate formal verification in the development process of our PLC-based control systems. [1]: http://cern.ch/project-plc-formalmethods [2]: http://cern.ch/plcverif

  20. Safety Verification for Probabilistic Hybrid Systems

    DEFF Research Database (Denmark)

    Zhang, Lijun; She, Zhikun; Ratschan, Stefan;

    2010-01-01

    The interplay of random phenomena and continuous real-time control deserves increased attention for instance in wireless sensing and control applications. Safety verification for such systems thus needs to consider probabilistic variations of systems with hybrid dynamics. In safety verification...... hybrid systems and develop a general abstraction technique for verifying probabilistic safety problems. This gives rise to the first mechanisable technique that can, in practice, formally verify safety properties of non-trivial continuous-time stochastic hybrid systems-without resorting to point...... of classical hybrid systems we are interested in whether a certain set of unsafe system states can be reached from a set of initial states. In the probabilistic setting, we may ask instead whether the probability of reaching unsafe states is below some given threshold. In this paper, we consider probabilistic...

  1. Safety Verification for Probabilistic Hybrid Systems

    DEFF Research Database (Denmark)

    Zhang, Lijun; She, Zhikun; Ratschan, Stefan;

    2012-01-01

    The interplay of random phenomena and continuous dynamics deserves increased attention, especially in the context of wireless sensing and control applications. Safety verification for such systems thus needs to consider probabilistic variants of systems with hybrid dynamics. In safety verification...... hybrid systems and develop a general abstraction technique for verifying probabilistic safety problems. This gives rise to the first mechanisable technique that can, in practice, formally verify safety properties of non-trivial continuous-time stochastic hybrid systems. Moreover, being based...... of classical hybrid systems, we are interested in whether a certain set of unsafe system states can be reached from a set of initial states. In the probabilistic setting, we may ask instead whether the probability of reaching unsafe states is below some given threshold. In this paper, we consider probabilistic...

  2. Sensor-fusion-based biometric identity verification

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, J.J.; Bouchard, A.M.; Osbourn, G.C.; Martinez, R.F.; Bartholomew, J.W. [Sandia National Labs., Albuquerque, NM (United States); Jordan, J.B.; Flachs, G.M.; Bao, Z.; Zhu, L. [New Mexico State Univ., Las Cruces, NM (United States). Electronic Vision Research Lab.

    1998-02-01

    Future generation automated human biometric identification and verification will require multiple features/sensors together with internal and external information sources to achieve high performance, accuracy, and reliability in uncontrolled environments. The primary objective of the proposed research is to develop a theoretical and practical basis for identifying and verifying people using standoff biometric features that can be obtained with minimal inconvenience during the verification process. The basic problem involves selecting sensors and discovering features that provide sufficient information to reliably verify a person`s identity under the uncertainties caused by measurement errors and tactics of uncooperative subjects. A system was developed for discovering hand, face, ear, and voice features and fusing them to verify the identity of people. The system obtains its robustness and reliability by fusing many coarse and easily measured features into a near minimal probability of error decision algorithm.

  3. Palm Vein Verification Using Gabor Filter

    Directory of Open Access Journals (Sweden)

    Ali Mohsin Al-Juboori

    2013-01-01

    Full Text Available Palm vein authentication is one of the modern biometric techniques, which employs the vein pattern in the human palm to verify the person. The merits of palm vein on classical biometric (e.g. fingerprint, iris, face are a low risk of falsification, difficulty of duplicated and stability. In this research, a new method is proposed for personal verification based on palm vein features. In the propose method, the palm vein images are firstly enhanced and then the features are extracted by using bank of Gabor filters. Then Fisher Discriminated Analysis (FDA is used to reduce the dimension of the features vectors. For vein pattern verification, this work uses Nearest Neighbors method. The EER of the proposed method is 0.2335%.

  4. Program Verification of Numerical Computation - Part 2

    OpenAIRE

    Pantelis, Garry

    2014-01-01

    These notes present some extensions of a formal method introduced in an earlier paper. The formal method is designed as a tool for program verification of numerical computation and forms the basis of the software package VPC. Included in the extensions that are presented here are disjunctions and methods for detecting non-computable programs. A more comprehensive list of the construction rules as higher order constructs is also presented.

  5. Functional Verification of Enhanced RISC Processor

    OpenAIRE

    SHANKER NILANGI; SOWMYA L

    2013-01-01

    This paper presents design and verification of a 32-bit enhanced RISC processor core having floating point computations integrated within the core, has been designed to reduce the cost and complexity. The designed 3 stage pipelined 32-bit RISC processor is based on the ARM7 processor architecture with single precision floating point multiplier, floating point adder/subtractor for floating point operations and 32 x 32 booths multiplier added to the integer core of ARM7. The binary representati...

  6. Survey of Existing Tools for Formal Verification.

    Energy Technology Data Exchange (ETDEWEB)

    Punnoose, Ratish J.; Armstrong, Robert C.; Wong, Matthew H.; Jackson, Mayo

    2014-12-01

    Formal methods have come into wide use because of their effectiveness in verifying "safety and security" requirements of digital systems; a set of requirements for which testing is mostly ineffective. Formal methods are routinely used in the design and verification of high-consequence digital systems in industry. This report outlines our work in assessing the capabilities of commercial and open source formal tools and the ways in which they can be leveraged in digital design workflows.

  7. Security Verification of Secure MANET Routing Protocols

    Science.gov (United States)

    2012-03-22

    the destination. The route discovery phase is complete upon receipt of the RREP at the requesting node. The DYMO protocol is a simpler version of AODV ...described in this appendix. The protocols are Secure AODV (SAODV), Secure Efficient Distance Vector (SEAD), and Secure Link State Routing Protocol (SLSP...SECURITY VERIFICATION OF SECURE MANET ROUTING PROTOCOLS THESIS Matthew F. Steele, Captain, USAF AFIT/GCS/ENG/12-03 DEPARTMENT OF THE AIR FORCE AIR

  8. Program verification using symbolic game semantics

    OpenAIRE

    Dimovski, Aleksandar

    2014-01-01

    We introduce a new symbolic representation of algorithmic game semantics, and show how it can be applied for efficient verification of open (incomplete) programs. The focus is on an Algol-like programming language which contains the core ingredients of imperative and functional languages, especially on its second-order recursion-free fragment with infinite data types. We revisit the regular-language representation of game semantics of this language fragment.By using symbolic values instead of...

  9. Verification tests for CANDU advanced fuel

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Chang Hwan; Chang, S.K.; Hong, S.D. [and others

    1997-07-01

    For the development of a CANDU advanced fuel, the CANFLEX-NU fuel bundles were tested under reactor operating conditions at the CANDU-Hot test loop. This report describes test results and test methods in the performance verification tests for the CANFLEX-NU bundle design. The main items described in the report are as follows. - Fuel bundle cross-flow test - Endurance fretting/vibration test - Freon CHF test - Production of technical document. (author). 25 refs., 45 tabs., 46 figs.

  10. Unconstrained Face Verification using Deep CNN Features

    OpenAIRE

    Chen, Jun-Cheng; Patel, Vishal M.; Chellappa, Rama

    2015-01-01

    In this paper, we present an algorithm for unconstrained face verification based on deep convolutional features and evaluate it on the newly released IARPA Janus Benchmark A (IJB-A) dataset. The IJB-A dataset includes real-world unconstrained faces from 500 subjects with full pose and illumination variations which are much harder than the traditional Labeled Face in the Wild (LFW) and Youtube Face (YTF) datasets. The deep convolutional neural network (DCNN) is trained using the CASIA-WebFace ...

  11. Formal System Verification for Trustworthy Embedded Systems

    Science.gov (United States)

    2011-04-19

    running on does not expose covert channels between unconnected objects) and liveness properties under fairness assumptions. Both Spiessens’ and Murray’s...security properties. If the assumptions of the verification hold, we have mathematical proof that, among other properties, the seL4 kernel is free of...KeyKOS [4], EROS [12], and Amoeba [8] do not provide means to explicitly define capability distributions. Capabilities are 1objects -- The object

  12. Verification of concurrent programs with Chalice

    OpenAIRE

    K. Rustan M. Leino; Müller, Peter; Smans, Jan

    2009-01-01

    A program verifier is a tool that allows developers to prove that their code satisfies its specification for every possible input and every thread schedule. These lecture notes describe a verifier for concurrent programs called Chalice. Chalice's verification methodology centers around permissions and permission transfer. In particular, a memory location may be accessed by a thread only if that thread has permission to do so. Proper use of permissions allows Chalice to deduce upper bound...

  13. Component Verification and Certification in NASA Missions

    Science.gov (United States)

    Giannakopoulou, Dimitra; Penix, John; Norvig, Peter (Technical Monitor)

    2001-01-01

    Software development for NASA missions is a particularly challenging task. Missions are extremely ambitious scientifically, have very strict time frames, and must be accomplished with a maximum degree of reliability. Verification technologies must therefore be pushed far beyond their current capabilities. Moreover, reuse and adaptation of software architectures and components must be incorporated in software development within and across missions. This paper discusses NASA applications that we are currently investigating from these perspectives.

  14. Verificator: Educational Tool for Learning Programming

    OpenAIRE

    Danijel RADOSEVIC; Tihomir OREHOVACKI; Alen LOVRENCIC

    2009-01-01

    The paper introduces Verificator, our learning programming interface aimed for learningprogramming in C++ at the university beginners’ level. In teaching programming some specificproblems concerning the teaching itself as well as the organization of the teaching process need tobe considered. One of the biggest problems is that students tend to adopt certain bad programminghabits in their attempt to more easily deal with their examinations, such as trying to write programswithout any syntax an...

  15. Formal verification of an avionics microprocessor

    Science.gov (United States)

    Srivas, Mandayam, K.; Miller, Steven P.

    1995-01-01

    Formal specification combined with mechanical verification is a promising approach for achieving the extremely high levels of assurance required of safety-critical digital systems. However, many questions remain regarding their use in practice: Can these techniques scale up to industrial systems, where are they likely to be useful, and how should industry go about incorporating them into practice? This report discusses a project undertaken to answer some of these questions, the formal verification of the AAMPS microprocessor. This project consisted of formally specifying in the PVS language a rockwell proprietary microprocessor at both the instruction-set and register-transfer levels and using the PVS theorem prover to show that the microcode correctly implemented the instruction-level specification for a representative subset of instructions. Notable aspects of this project include the use of a formal specification language by practicing hardware and software engineers, the integration of traditional inspections with formal specifications, and the use of a mechanical theorem prover to verify a portion of a commercial, pipelined microprocessor that was not explicitly designed for formal verification.

  16. The MODUS Approach to Formal Verification

    Directory of Open Access Journals (Sweden)

    Brewka Lukasz

    2014-03-01

    Full Text Available Background: Software reliability is of great importance for the development of embedded systems that are often used in applications that have requirements for safety. Since the life cycle of embedded products is becoming shorter, productivity and quality simultaneously required and closely in the process of providing competitive products Objectives: In relation to this, MODUS (Method and supporting toolset advancing embedded systems quality project aims to provide small and medium-sized businesses ways to improve their position in the embedded market through a pragmatic and viable solution Methods/Approach: This paper will describe the MODUS project with focus on the technical methodologies that can assist formal verification and formal model checking. Results: Based on automated analysis of the characteristics of the system and by controlling the choice of the existing opensource model verification engines, model verification producing inputs to be fed into these engines. Conclusions: The MODUS approach is aligned with present market needs; the familiarity with tools, the ease of use and compatibility/interoperability remain among the most important criteria when selecting the development environment for a project

  17. Spatial verification using wavelet transforms: a review

    Science.gov (United States)

    Weniger, Michael; Kapp, Florian; Friederichs, Petra

    2017-01-01

    Due to the emergence of new high resolution numerical weather prediction (NWP) models and the availability of new or more reliable remote sensing data, the importance of efficient spatial verification techniques is growing. Wavelet transforms offer an effective framework to decompose spatial data into separate (and possibly orthogonal) scales and directions. Most wavelet based spatial verification techniques have been developed or refined in the last decade and concentrate on assessing forecast performance (i.e. forecast skill or forecast error) on distinct physical scales. Particularly during the last five years, a significant growth in meteorological applications could be observed. However, a comparison with other scientific fields such as feature detection, image fusion, texture analysis, or facial and biometric recognition, shows that there is still a considerable, currently unused potential to derive useful diagnostic information. In order to tab the full potential of wavelet analysis, we revise the state-of-the art in one- and two-dimensional wavelet analysis and its application with emphasis on spatial verification. We further use a technique developed for texture analysis in the context of high-resolution quantitative precipitation forecasts, which is able to assess structural characteristics of the precipitation fields and allows efficient clustering of ensemble data.

  18. Observation of online communities

    DEFF Research Database (Denmark)

    Nørskov, Sladjana V.; Rask, Morten

    2011-01-01

    This paper addresses the application of observation to online settings with a special focus on observer roles. It draws on a study of online observation of a virtual community, i.e. an open source software (OSS) community. The paper examines general and specific advantages and disadvantages...... of the observer roles in online settings by relating these roles to the same roles assumed in offline settings. The study suggests that under the right circumstances online and offline observation may benefit from being combined as they complement each other well. Quality issues and factors important to elicit...... trustworthy observational data from online study settings, such as OSS communities, are discussed. A proposition is made concerning how threats to credibility and transferability in relation to online observation (i.e. lack of richness and detail, risk of misunderstandings) can be diminished, while...

  19. Technical safety requirements control level verification

    Energy Technology Data Exchange (ETDEWEB)

    STEWART, J.L.

    1999-05-21

    A Technical Safety Requirement (TSR) control level verification process was developed for the Tank Waste Remediation System (TWRS) TSRs at the Hanford Site in Richland, WA, at the direction of the US. Department of Energy, Richland Operations Office (RL). The objective of the effort was to develop a process to ensure that the TWRS TSR controls are designated and managed at the appropriate levels as Safety Limits (SLs), Limiting Control Settings (LCSs), Limiting Conditions for Operation (LCOs), Administrative Controls (ACs), or Design Features. The TSR control level verification process was developed and implemented by a team of contractor personnel with the participation of Fluor Daniel Hanford, Inc. (FDH), the Project Hanford Management Contract (PHMC) integrating contractor, and RL representatives. The team was composed of individuals with the following experience base: nuclear safety analysis; licensing; nuclear industry and DOE-complex TSR preparation/review experience; tank farm operations; FDH policy and compliance; and RL-TWRS oversight. Each TSR control level designation was completed utilizing TSR control logic diagrams and TSR criteria checklists based on DOE Orders, Standards, Contractor TSR policy, and other guidance. The control logic diagrams and criteria checklists were reviewed and modified by team members during team meetings. The TSR control level verification process was used to systematically evaluate 12 LCOs, 22 AC programs, and approximately 100 program key elements identified in the TWRS TSR document. The verification of each TSR control required a team consensus. Based on the results of the process, refinements were identified and the TWRS TSRs were modified as appropriate. A final report documenting key assumptions and the control level designation for each TSR control was prepared and is maintained on file for future reference. The results of the process were used as a reference in the RL review of the final TWRS TSRs and control suite. RL

  20. ONLINE PUBLISHING CURRENT SCENARIO

    Directory of Open Access Journals (Sweden)

    Balasubramanian Thiagarajan

    2012-12-01

    Full Text Available This article attempts to unravel the current scenario in online publishing. Advent of internet has brought with it tremendous changes in the publishing industry. What was hither to an industry dominated by publisher has been thrown open to one and sundry. Online publishing has brought with it a reach which was hitherto never been imagined. In the normal course it would take at least a year to publish a manuscript. Online publishing has managed to bring this time down to a few weeks / at most a month. This article attempts to discusses the positives and perils of online publishing scenario.

  1. Online shopping hesitation.

    Science.gov (United States)

    Cho, Chang-Hoan; Kang, Jaewon; Cheon, Hongsik John

    2006-06-01

    This study was designed to understand which factors influence consumer hesitation or delay in online product purchases. The study examined four groups of variables (i.e., consumer characteristics, contextual factors perceived uncertainty factors, and medium/channel innovation factors) that predict three types of online shopping hesitation (i.e., overall hesitation, shopping cart abandonment, and hesitation at the final payment stage). We found that different sets of delay factors are related to different aspects of online shopping hesitation. The study concludes with suggestion for various delay-reduction devices to help consumers close their online decision hesitation.

  2. Observation of online communities

    DEFF Research Database (Denmark)

    Nørskov, Sladjana V.; Rask, Morten

    2011-01-01

    This paper addresses the application of observation to online settings with a special focus on observer roles. It draws on a study of online observation of a virtual community, i.e. an open source software (OSS) community. The paper examines general and specific advantages and disadvantages...... of the observer roles in online settings by relating these roles to the same roles assumed in offline settings. The study suggests that under the right circumstances online and offline observation may benefit from being combined as they complement each other well. Quality issues and factors important to elicit...

  3. Online Shopping Woes

    Institute of Scientific and Technical Information of China (English)

    Hou Weili

    2011-01-01

    AS a frequent online shopper,Zhou Fangjie,a 28-year-old white-collar worker,was annoyed when she could not open Hanyidushe,an online shop selling Korean-style clothing on Taobao Mall.Her experience resulted from the online protest initiated by small vendors on Taobao Mall,China's largest business to consumer online platform.Thousands of small vendors started the protest against larger established vendors by discrediting them through False orders,forming an anti-Taobao Union and setting up a chat room to devise ways to disrupt operations on Taobao Mall.

  4. Online organic chemistry

    Science.gov (United States)

    Janowicz, Philip A.

    This is a comprehensive study of the many facets of an entirely online organic chemistry course. Online homework with structure-drawing capabilities was found to be more effective than written homework. Online lecture was found to be just as effective as in-person lecture, and students prefer an online lecture format with shorter Webcasts. Online office hours were found to be effective, and discussion sessions can be placed online as well. A model was created that explains 36.1% of student performance based on GPA, ACT Math score, grade in previous chemistry course, and attendance at various forms of discussion. Online exams have been created which test problem-solving skills and is instantly gradable. In these exams, students can submit answers until time runs out for different numbers of points. These facets were combined effectively to create an entirely online organic chemistry course which students prefer over the in-person alternative. Lastly, there is a vision for where online organic chemistry is going and what can be done to improve education for all.

  5. Abstraction and Learning for Infinite-State Compositional Verification

    Directory of Open Access Journals (Sweden)

    Dimitra Giannakopoulou

    2013-09-01

    Full Text Available Despite many advances that enable the application of model checking techniques to the verification of large systems, the state-explosion problem remains the main challenge for scalability. Compositional verification addresses this challenge by decomposing the verification of a large system into the verification of its components. Recent techniques use learning-based approaches to automate compositional verification based on the assume-guarantee style reasoning. However, these techniques are only applicable to finite-state systems. In this work, we propose a new framework that interleaves abstraction and learning to perform automated compositional verification of infinite-state systems. We also discuss the role of learning and abstraction in the related context of interface generation for infinite-state components.

  6. Secure Position Verification for Wireless Sensor Networks in Noisy Channels

    CERN Document Server

    Mandal, Partha Sarathi

    2011-01-01

    Position verification in wireless sensor networks (WSNs) is quite tricky in presence of attackers (malicious sensor nodes), who try to break the verification protocol by reporting their incorrect positions (locations) during the verification stage. In the literature of WSNs, most of the existing methods of position verification have used trusted verifiers, which are in fact vulnerable to attacks by malicious nodes. They also depend on some distance estimation techniques, which are not accurate in noisy channels (mediums). In this article, we propose a secure position verification scheme for WSNs in noisy channels without relying on any trusted entities. Our verification scheme detects and filters out all malicious nodes from the network with very high probability.

  7. Social Security Number Verification Service (SSNVS)

    Data.gov (United States)

    Social Security Administration — SSNVS is a service offered by SSA's Business Services Online (BSO). It is used by employers and certain third-party submitters to verify the accuracy of the names...

  8. Thoughts on Verification of Nuclear Disarmament

    Energy Technology Data Exchange (ETDEWEB)

    Dunlop, W H

    2007-09-26

    It is my pleasure to be here to day to participate in this Conference. My thanks to the organizers for preparing such an interesting agenda on a very difficult topic. My effort in preparing my presentation was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. And as many of you know Lawrence Livermore National Laboratory is now, as of Oct 1st, under contract to the Lawrence Livermore National Security LLC. There has been a long history of how to view verification of arms control agreements. The basis for verification during the days of SALT was that verification would be based on each country's national technical means. For treaties dealing with strategic missiles this worked well as the individual items subject to verification were of such a size that they were visible by the National Technical Means available at the time. And it was felt that the counting of missiles and launchers could be verified by our National Technical Means. For nuclear testing treaties the use of seismic measurements developed into a capability that was reasonably robust for all but the smallest of nuclear tests. However, once we had the Threshold Test Ban Treaty, there was a significant problem in that the fidelity of the measurements were not sufficient to determine if a test was slightly above the 150 kt limit or slightly below the 150 kt limit. This led some in the US to believe that the Soviet Union was not living up to the TTBT agreement. An on-site verification protocol was negotiated in 1988 and 1989 that allowed the US to make hydrodynamic yield measurements on Soviet tests above 50 kt yield and regional seismic measurements on all tests above 35 kt of yield; and the Soviets to make the same type of measurements on US tests to ensure that they were not over 150 kt. These on-site measurements were considered reasonably intrusive. Again the measurement capability was

  9. Verification-Based Interval-Passing Algorithm for Compressed Sensing

    OpenAIRE

    Wu, Xiaofu; Yang, Zhen

    2013-01-01

    We propose a verification-based Interval-Passing (IP) algorithm for iteratively reconstruction of nonnegative sparse signals using parity check matrices of low-density parity check (LDPC) codes as measurement matrices. The proposed algorithm can be considered as an improved IP algorithm by further incorporation of the mechanism of verification algorithm. It is proved that the proposed algorithm performs always better than either the IP algorithm or the verification algorithm. Simulation resul...

  10. USER CONTEXT MODELS : A FRAMEWORK TO EASE SOFTWARE FORMAL VERIFICATIONS

    OpenAIRE

    2010-01-01

    This article is accepted to appear in ICEIS 2010 proceedings; International audience; Several works emphasize the difficulties of software verification applied to embedded systems. In past years, formal verification techniques and tools were widely developed and used by the research community. However, the use of formal verification at industrial scale remains difficult, expensive and requires lot of time. This is due to the size and the complexity of manipulated models, but also, to the impo...

  11. Verification and validation plan for the SFR system analysis module

    Energy Technology Data Exchange (ETDEWEB)

    Hu, R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-12-18

    This report documents the Verification and Validation (V&V) Plan for software verification and validation of the SFR System Analysis Module (SAM), developed at Argonne National Laboratory for sodium fast reactor whole-plant transient analysis. SAM is developed under the DOE NEAMS program and is part of the Reactor Product Line toolkit. The SAM code, the phenomena and computational models of interest, the software quality assurance, and the verification and validation requirements and plans are discussed in this report.

  12. [PIV: a computer-aided portal image verification system].

    Science.gov (United States)

    Fu, Weihua; Zhang, Hongzhi; Wu, Jing

    2002-12-01

    Portal image verification (PIV) is one of the key actions in QA procedure for sophisticated accurate radiotherapy. The purpose of this study was to develop a PIV software as a tool for improving the accuracy and visualization of portal field verification and computing field placement errors. PIV was developed in the visual C++ integrated environment under Windows 95 operating system. It can improve visualization by providing tools for image processing and multimode images display. Semi-automatic register methods make verification more accurate than view-box method. It can provide useful quantitative errors for regular fields. PIV is flexible and accurate. It is an effective tool for portal field verification.

  13. Verification and Validation of Flight Critical Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Verification and Validation is a multi-disciplinary activity that encompasses elements of systems engineering, safety, software engineering and test. The elements...

  14. NEMVP: North American energy measurement and verification protocol

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This measurement and verification protocol discusses procedures that,when implemented, allow buyers, sellers, and financiers of energy projects to quantify energy conservation measure performance and savings.

  15. Compositional verification of real-time systems using Ecdar

    DEFF Research Database (Denmark)

    David, A.; Larsen, K.G.; Møller, M.H.;

    2012-01-01

    We present a specification theory for timed systems implemented in the Ecdar tool. We illustrate the operations of the specification theory on a running example, showing the models and verification checks. To demonstrate the power of the compositional verification, we perform an in depth case study...... of a leader election protocol; Modeling it in Ecdar as Timed input/output automata Specifications and performing both monolithic and compositional verification of two interesting properties on it. We compare the execution time of the compositional to the classical verification showing a huge difference...

  16. Tolerance Verification of Micro and Nano Structures on Polycarbonate Substrates

    DEFF Research Database (Denmark)

    Gasparin, Stefania; Tosello, Guido; Hansen, Hans Nørgaard

    2010-01-01

    Micro and nano structures are an increasing challenge in terms of tolerance verification and process quality control: smaller dimensions led to a smaller tolerance zone to be evaluated. This paper focuses on the verification of CD, DVD and HD-DVD nanoscale features. CD tolerance features are defi......Micro and nano structures are an increasing challenge in terms of tolerance verification and process quality control: smaller dimensions led to a smaller tolerance zone to be evaluated. This paper focuses on the verification of CD, DVD and HD-DVD nanoscale features. CD tolerance features...

  17. The Cognitive Agents Specification Language and Verification Environment

    Science.gov (United States)

    Shapiro, S.; Lespérance, Y.; Levesque, H. J.

    The Cognitive Agents Specification Language (CASL) is a framework for specifying multiagent systems. It has a mix of declarative and procedural components to facilitate the specification and verification of complex multiagent systems. In this chapter, we describe CASL and a verification environment (CASLve) for it based on the PVS verification system. We give an example of a multiagent meeting scheduler application specified with CASL. To illustrate the verification system, we discuss a proof we carried out in it, namely, that all bounded-loop CASL specifications terminate.

  18. A Synthesized Framework for Formal Verification of Computing Systems

    Directory of Open Access Journals (Sweden)

    Nikola Bogunovic

    2003-12-01

    Full Text Available Design process of computing systems gradually evolved to a level that encompasses formal verification techniques. However, the integration of formal verification techniques into a methodical design procedure has many inherent miscomprehensions and problems. The paper explicates the discrepancy between the real system implementation and the abstracted model that is actually used in the formal verification procedure. Particular attention is paid to the seamless integration of all phases of the verification procedure that encompasses definition of the specification language and denotation and execution of conformance relation between the abstracted model and its intended behavior. The concealed obstacles are exposed, computationally expensive steps identified and possible improvements proposed.

  19. An Efficient Location Verification Scheme for Static Wireless Sensor Networks.

    Science.gov (United States)

    Kim, In-Hwan; Kim, Bo-Sung; Song, JooSeok

    2017-01-24

    In wireless sensor networks (WSNs), the accuracy of location information is vital to support many interesting applications. Unfortunately, sensors have difficulty in estimating their location when malicious sensors attack the location estimation process. Even though secure localization schemes have been proposed to protect location estimation process from attacks, they are not enough to eliminate the wrong location estimations in some situations. The location verification can be the solution to the situations or be the second-line defense. The problem of most of the location verifications is the explicit involvement of many sensors in the verification process and requirements, such as special hardware, a dedicated verifier and the trusted third party, which causes more communication and computation overhead. In this paper, we propose an efficient location verification scheme for static WSN called mutually-shared region-based location verification (MSRLV), which reduces those overheads by utilizing the implicit involvement of sensors and eliminating several requirements. In order to achieve this, we use the mutually-shared region between location claimant and verifier for the location verification. The analysis shows that MSRLV reduces communication overhead by 77% and computation overhead by 92% on average, when compared with the other location verification schemes, in a single sensor verification. In addition, simulation results for the verification of the whole network show that MSRLV can detect the malicious sensors by over 90% when sensors in the network have five or more neighbors.

  20. Consumers' Online Brand Endorsements

    NARCIS (Netherlands)

    Bernritter, S.F.; Verlegh, P.W.J.; Smit, E.G.; De Pelsmacker, P.

    2016-01-01

    Abstract Purpose and Approach This Chapter has three central goals: First, it aims to introduce the concept of consumers’ online brand endorsements, which we define as consumers’ intentional, public, and positive online affiliations with brands (e.g., liking a brand page on Facebook). Second, it pro

  1. Quality online personalisation

    NARCIS (Netherlands)

    T. Li (Ting); T. Unger (Till)

    2012-01-01

    textabstractWhen done right, personalisation online can be an effective way to enhance the buying or consuming experience, thus stimulating purchasing. However, it can also rely heavily on customers’ private details, a very sensitive and currently hot issue. So, how do online marketeers deal with th

  2. Framework for online teaching

    DEFF Research Database (Denmark)

    Strobel, Bjarne W.

    2014-01-01

    The following framework for online teaching is a guidance to inspire you on how to to use e-learning in your teaching. Maybe you want to make a whole online course (distance learning) or maybe you want to use e-learning as a part of a course (blended learning). If you want to go further or have...

  3. StuDIY Online

    DEFF Research Database (Denmark)

    2015-01-01

    StuDIY Online er kurser i akademisk argumentation, problemformulering, analyse og akademisk sprog. Kurserne er frit tilgængelige for alle via Blackboard på AU......StuDIY Online er kurser i akademisk argumentation, problemformulering, analyse og akademisk sprog. Kurserne er frit tilgængelige for alle via Blackboard på AU...

  4. Consumers' Online Brand Endorsements

    NARCIS (Netherlands)

    Bernritter, S.F.; Verlegh, P.W.J.; Smit, E.G.; De Pelsmacker, P.

    2016-01-01

    Purpose and Approach This Chapter has three central goals: First, it aims to introduce the concept of consumers’ online brand endorsements, which we define as consumers’ intentional, public, and positive online affiliations with brands (e.g., liking a brand page on Facebook). Second, it provides an

  5. Online Reading Test Evaluation

    Institute of Scientific and Technical Information of China (English)

    雷鸣

    2011-01-01

    Language test has been used as a scientific assessment tool in providing valuable information for teaching and learning. In fact,lots of online reading tests are not designed with validity. This paper analyzes those online reading tests from the aspects o

  6. Online consumer contracts

    NARCIS (Netherlands)

    Luzak, J.

    2014-01-01

    The new Consumer Rights Directive introduced some changes to the level of consumers’ protection online. However, just like with its predecessor, the Distance Selling Directive, the main focus of the protection that consumers have been granted online is to provide them with transparent and salient

  7. Consumers' Online Brand Endorsements

    NARCIS (Netherlands)

    Bernritter, S.F.; Verlegh, P.W.J.; Smit, E.G.; De Pelsmacker, P.

    2016-01-01

    Purpose and Approach This Chapter has three central goals: First, it aims to introduce the concept of consumers’ online brand endorsements, which we define as consumers’ intentional, public, and positive online affiliations with brands (e.g., liking a brand page on Facebook). Second, it provides an

  8. Online Readiness Rijscholen 2013

    NARCIS (Netherlands)

    Weltevreden, J.W.J.; Boels, D.H.H.

    2013-01-01

    In dit onderzoek is de online readiness van rijscholen in 2013 in kaart gebracht. In totaal hebben 115 rijscholen deelgenomen aan het onderzoek. Het onderzoek is uitgevoerd door het lectoraat Online Ondernemen samen met studenten van de minor Marketing Tomorrow van de Hogeschool van Amsterdam.

  9. Quality online personalisation

    NARCIS (Netherlands)

    T. Li (Ting); T. Unger (Till)

    2012-01-01

    textabstractWhen done right, personalisation online can be an effective way to enhance the buying or consuming experience, thus stimulating purchasing. However, it can also rely heavily on customers’ private details, a very sensitive and currently hot issue. So, how do online marketeers deal

  10. Framework for online teaching

    DEFF Research Database (Denmark)

    Strobel, Bjarne W.

    2014-01-01

    The following framework for online teaching is a guidance to inspire you on how to to use e-learning in your teaching. Maybe you want to make a whole online course (distance learning) or maybe you want to use e-learning as a part of a course (blended learning). If you want to go further or have...

  11. Online Advertising in Social Networks

    Science.gov (United States)

    Bagherjeiran, Abraham; Bhatt, Rushi P.; Parekh, Rajesh; Chaoji, Vineet

    Online social networks offer opportunities to analyze user behavior and social connectivity and leverage resulting insights for effective online advertising. This chapter focuses on the role of social network information in online display advertising.

  12. 78 FR 6852 - Agency Information Collection (Student Verification of Enrollment) Activity Under OMB Review

    Science.gov (United States)

    2013-01-31

    ... AFFAIRS Agency Information Collection (Student Verification of Enrollment) Activity Under OMB Review....'' SUPPLEMENTARY INFORMATION: Title: Student Verification of Enrollment, VA Form 22-8979. OMB Control Number: 2900... a student's certification of actual attendance and verification of the student's...

  13. Spatial Evaluation and Verification of Earthquake Simulators

    Science.gov (United States)

    Wilson, John Max; Yoder, Mark R.; Rundle, John B.; Turcotte, Donald L.; Schultz, Kasey W.

    2016-09-01

    In this paper, we address the problem of verifying earthquake simulators with observed data. Earthquake simulators are a class of computational simulations which attempt to mirror the topological complexity of fault systems on which earthquakes occur. In addition, the physics of friction and elastic interactions between fault elements are included in these simulations. Simulation parameters are adjusted so that natural earthquake sequences are matched in their scaling properties. Physically based earthquake simulators can generate many thousands of years of simulated seismicity, allowing for a robust capture of the statistical properties of large, damaging earthquakes that have long recurrence time scales. Verification of simulations against current observed earthquake seismicity is necessary, and following past simulator and forecast model verification methods, we approach the challenges in spatial forecast verification to simulators; namely, that simulator outputs are confined to the modeled faults, while observed earthquake epicenters often occur off of known faults. We present two methods for addressing this discrepancy: a simplistic approach whereby observed earthquakes are shifted to the nearest fault element and a smoothing method based on the power laws of the epidemic-type aftershock (ETAS) model, which distributes the seismicity of each simulated earthquake over the entire test region at a decaying rate with epicentral distance. To test these methods, a receiver operating characteristic plot was produced by comparing the rate maps to observed m>6.0 earthquakes in California since 1980. We found that the nearest-neighbor mapping produced poor forecasts, while the ETAS power-law method produced rate maps that agreed reasonably well with observations.

  14. Spatial Evaluation and Verification of Earthquake Simulators

    Science.gov (United States)

    Wilson, John Max; Yoder, Mark R.; Rundle, John B.; Turcotte, Donald L.; Schultz, Kasey W.

    2017-06-01

    In this paper, we address the problem of verifying earthquake simulators with observed data. Earthquake simulators are a class of computational simulations which attempt to mirror the topological complexity of fault systems on which earthquakes occur. In addition, the physics of friction and elastic interactions between fault elements are included in these simulations. Simulation parameters are adjusted so that natural earthquake sequences are matched in their scaling properties. Physically based earthquake simulators can generate many thousands of years of simulated seismicity, allowing for a robust capture of the statistical properties of large, damaging earthquakes that have long recurrence time scales. Verification of simulations against current observed earthquake seismicity is necessary, and following past simulator and forecast model verification methods, we approach the challenges in spatial forecast verification to simulators; namely, that simulator outputs are confined to the modeled faults, while observed earthquake epicenters often occur off of known faults. We present two methods for addressing this discrepancy: a simplistic approach whereby observed earthquakes are shifted to the nearest fault element and a smoothing method based on the power laws of the epidemic-type aftershock (ETAS) model, which distributes the seismicity of each simulated earthquake over the entire test region at a decaying rate with epicentral distance. To test these methods, a receiver operating characteristic plot was produced by comparing the rate maps to observed m>6.0 earthquakes in California since 1980. We found that the nearest-neighbor mapping produced poor forecasts, while the ETAS power-law method produced rate maps that agreed reasonably well with observations.

  15. Experimental verification of a large flexible manipulator

    Science.gov (United States)

    Lee, Jac Won; Huggins, James D.; Book, Wayne J.

    1988-01-01

    A large experimental lightweight manipulator would be useful for material handling, for welding, or for ultrasonic inspection of a large structure, such as an airframe. The flexible parallel link mechanism is designed for high rigidity without increasing weight. This constrained system is analyzed by singular value decomposition of the constraint Jacobian matrix. A verification of the modeling using the assumed mode method is presented. Eigenvalues and eigenvectors of the linearized model are compared to the measured system natural frequencies and their associated mode shapes. The modeling results for large motions are compared to the time response data from the experiments. The hydraulic actuator is verified.

  16. ALMA Polarization Science Verification: 3C 286

    Science.gov (United States)

    Nagai, H.; Nakanishi, K.; Paladino, R.; Moellenbrock, G.; Fomalont, E.; Amigano, A.; Vlahakis, C.; Remijan, A.; ALMA Polarization Team

    2015-12-01

    The ALMA polarization science verification results on 3C 286 are presented. The measured polarization percentage and polarization position angle of the continuum emission at 1.3 mm are about 16% and 39 degrees, respectively. They are quite similar to those at longer wavelength, but seem to increase slightly. Similar trends were also found in the previous measurement using the IRAM 30-m telescope (Agudo et al. 2012). The final image rms on the polarization image is better than 0.1% of the total intensity, demonstrating the very high polarization sensitivity of ALMA.

  17. Unification & sharing in timed automata verification

    DEFF Research Database (Denmark)

    David, Alexandre; Behrmann, Gerd; Larsen, Kim Guldstrand

    2003-01-01

    We present the design of the model-checking engine and internal data structures for the next generation of UPPAAL. The design is based on a pipeline architecture where each stage represents one independent operation in the verification algorithms. The architecture is based on essentially one shared...... data structure to reduce redundant computations in state exploration, which unifies the so-called passed and waiting lists of the traditional reachability algorithm. In the implementation, instead of using standard memory management functions from general-purpose operating systems, we have developed...

  18. Accelerating functional verification of an integrated circuit

    Energy Technology Data Exchange (ETDEWEB)

    Deindl, Michael; Ruedinger, Jeffrey Joseph; Zoellin, Christian G.

    2015-10-27

    Illustrative embodiments include a method, system, and computer program product for accelerating functional verification in simulation testing of an integrated circuit (IC). Using a processor and a memory, a serial operation is replaced with a direct register access operation, wherein the serial operation is configured to perform bit shifting operation using a register in a simulation of the IC. The serial operation is blocked from manipulating the register in the simulation of the IC. Using the register in the simulation of the IC, the direct register access operation is performed in place of the serial operation.

  19. Verification of pneumatic railway brake models

    Science.gov (United States)

    Piechowiak, Tadeusz

    2010-03-01

    The article presents a survey of diverse methods for validation of pneumatic train brake modelling. Various experimental measurements of railway pneumatic brakes were made chiefly on a test stand at Poznań University of Technology; other test stands and some results have been taken from the literature. The measurements, some of them unconventional, were performed on separate pneumatic elements, brake devices, the brake pipe and fragments thereof. Mechanical devices were also included. The experimental measurement results were used for the verification of numerical models and for the determination of parameters. The latter was partially performed using an optimisation method.

  20. Dynamic statechart verification; Dynamische Zustandsautomaten Verifikation

    Energy Technology Data Exchange (ETDEWEB)

    Braitschink, P. [Volkswagen AG, Wolfsburg (Germany); Reuss, H.C. [IVK, Univ. Stuttgart (Germany)

    2005-07-01

    In today's vehicles a great number of functions are realized by statecharts: from electrical window lift systems to entry systems and finally driver assistance systems. The methodology presented in this paper can be used for test verification during function tests both in subsystems and in the complete vehicle system. The principle of the methodology can be applied to different models (UML, MATLAB/ Stateflow, ASCET-SD, etc.) for the representation of statecharts. The standardized data exchange format ASAM/ODX is used to store the data. (orig.)

  1. Predicting SMT Solver Performance for Software Verification

    Directory of Open Access Journals (Sweden)

    Andrew Healy

    2017-01-01

    Full Text Available The Why3 IDE and verification system facilitates the use of a wide range of Satisfiability Modulo Theories (SMT solvers through a driver-based architecture. We present Where4: a portfolio-based approach to discharge Why3 proof obligations. We use data analysis and machine learning techniques on static metrics derived from program source code. Our approach benefits software engineers by providing a single utility to delegate proof obligations to the solvers most likely to return a useful result. It does this in a time-efficient way using existing Why3 and solver installations - without requiring low-level knowledge about SMT solver operation from the user.

  2. Fingerprint Verification based on Gabor Filter Enhancement

    CERN Document Server

    Lavanya, B N; Venugopal, K R

    2009-01-01

    Human fingerprints are reliable characteristics for personnel identification as it is unique and persistence. A fingerprint pattern consists of ridges, valleys and minutiae. In this paper we propose Fingerprint Verification based on Gabor Filter Enhancement (FVGFE) algorithm for minutiae feature extraction and post processing based on 9 pixel neighborhood. A global feature extraction and fingerprints enhancement are based on Hong enhancement method which is simultaneously able to extract local ridge orientation and ridge frequency. It is observed that the Sensitivity and Specificity values are better compared to the existing algorithms.

  3. On-machine dimensional verification. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rendulic, W.

    1993-08-01

    General technology for automating in-process verification of machined products has been studied and implemented on a variety of machines and products at AlliedSignal Inc., Kansas City Division (KCD). Tests have been performed to establish system accuracy and probe reliability on two numerically controlled machining centers. Commercial software has been revised, and new cycles such as skew check and skew machining, have been developed to enhance and expand probing capabilities. Probe benefits have been demonstrated in the area of setup, cycle time, part quality, tooling cost, and product sampling.

  4. State of the Art: Signature Biometrics Verification

    Directory of Open Access Journals (Sweden)

    Nourddine Guersi

    2010-04-01

    Full Text Available This paper presents a comparative analysis of the performance of three estimation algorithms: Expectation Maximization (EM, Greedy EM Algorithm (GEM and Figueiredo-Jain Algorithm (FJ - based on the Gaussian mixture models (GMMs for signature biometrics verification. The simulation results have shown significant performance achievements. The test performance of EER=5.49 % for "EM", EER=5.04 % for "GEM" and EER=5.00 % for "FJ", shows that the behavioral information scheme of signature biometrics is robust and has a discriminating power, which can be explored for identity authentication.

  5. Online Sellers’ Website Quality Influencing Online Buyers’ Purchase Intention

    Science.gov (United States)

    Shea Lee, Tan; Ariff, Mohd Shoki Md; Zakuan, Norhayati; Sulaiman, Zuraidah; Zameri Mat Saman, Muhamad

    2016-05-01

    The increase adoption of Internet among young users in Malaysia provides high prospect for online seller. Young users aged between 18 and 25 years old are important to online sellers because they are actively involved in online purchasing and this group of online buyers is expected to dominate future online market. Therefore, examining online sellers’ website quality and online buyers’ purchase intention is crucial. Based on the Theory of planned behavior (TPB), a conceptual model of online sellers’ website quality and purchase intention of online buyers was developed. E-tailQ instrument was adapted in this study which composed of website design, reliability/fulfillment, security, privacy & trust, and customer service. Using online questionnaire and convenience sampling procedure, primary data were obtained from 240 online buyers aged between 18 to 25 years old. It was discovered that website design, website reliability/fulfillment, website security, privacy & trust, and website customer service positively and significantly influence intention of online buyers to continuously purchase via online channels. This study concludes that online sellers’ website quality is important in predicting online buyers’ purchase intention. Recommendation and implication of this study were discussed focusing on how online sellers should improve their website quality to stay competitive in online business.

  6. Entre controversias científico-médicas y movilizaciones populares. Población epidémica y vacunas contra la fiebre hemorrágica argentina 1958-1990

    Directory of Open Access Journals (Sweden)

    Agnese, Graciela

    2013-06-01

    Full Text Available The emergence and gradual extension of a new epidemic disease, as it has been the Haemorrhagic Fever Argentina, from the Decade of the ‘ 50s, prompted the medical scientific research with the aim of finding a vaccine. In the period 1959-1990 developed three projects of vaccines with different results. This article aims to consider the behavior assumed by the epidemic population around the three vaccines in response to the tensions that exist between population and physicians and researchers in charge of vaccination campaigns; the struggles between the various scientific groups; the role of the press and the State.La irrupción y la progresiva extensión de una nueva enfermedad epidémica, como ha sido la Fiebre Hemorrágica Argentina, a partir de la década del ’50, impulsó la investigación científica médica con el objetivo fundamental de encontrar una vacuna. En el período 1959-1990 se desarrollaron tres proyectos de vacunas con distintos resultados. El objetivo de este artículo es considerar las conductas asumidas por la población epidémica en torno a las tres vacunas atendiendo a las tensiones existentes entre la población y los médicos e investigadores a cargo de las campañas de vacunación; las pugnas entre los distintos grupos científicos; el rol de la prensa y del estado.

  7. Epidermal growth factor enemas for induction of remission in left-sided ulcerative colitis Enemas de factor de crecimiento epidérmico para inducir la remisión de la colitis ulcerosa izquierda

    Directory of Open Access Journals (Sweden)

    Hugo Nodarse-Cuní

    2013-03-01

    Full Text Available Introduction: ulcerative colitis is a little known chronic inflammatory disease in colonic mucosa. The positive effect of epidermal growth factor was shown in a previous report, with enema use for treatment of mild to moderate left-sided manifestation of the disease. This evidence provided the basis for evaluating the efficacy and safety profile of a viscous solution of this product. Methods: thirty-one patients were randomized to three groups for daily medications during 14 days. Twelve received one 10 mg enema of epidermal growth factor dissolved in 100 mL of viscous solution whereas nine were treated with placebo enema; both groups also received 1.2 g of oral mesalamine per day. The other group included ten patients with 3 g / 100 mL of mesalamine enema. Primary end point was clinical responses after two weeks of treatment, defined as a decreased of, at least three points from baseline, the Disease Activity Index and endoscopic or histological evidences of improvement. Results: remission of disease was observed in all patients in the epidermal growth factor group, and six in both, mesalamine enema and placebo group. All the comparisons between groups showed statistically significant superiority for epidermal growth factor, the only product with significant reduction in disease activity index as well as the presence and intensity of digestive symptoms in patients after treatment. None adverse event was reported. Conclusions: the results agree with previous molecular and clinical evidences, indicating that the epidermal growth factor is effective to reduce disease activity and to induce remission. A new study involving more patients should be conducted to confirm the efficacy of the epidermal growth factor enemas.Introducción: la colitis ulcerosa es una enfermedad inflamatoria crónica de etiología poco conocida, que afecta la mucosa del colon. El efecto positivo del factor de crecimiento epidérmico fue reportado en estudio previo con uso de

  8. Verification of concurrent systems with VerCors

    NARCIS (Netherlands)

    Amighi, A.; Blom, Stefan; Darabi, Saeed; Huisman, Marieke; Mostowski, Wojciech; Zaharieva, M.; Bernardo, Marco; Damiani, Ferruccio; Hahnle, Reiner; Johnsen, Einar; Schaefer, Ina

    This paper presents the VerCors approach to verification of concurrent software. It first discusses why verification of concurrent software is important, but also challenging. Then it shows how within the VerCors project we use permission-based separation logic to reason about multithreaded Java

  9. CMOS VLSI Layout and Verification of a SIMD Computer

    Science.gov (United States)

    Zheng, Jianqing

    1996-01-01

    A CMOS VLSI layout and verification of a 3 x 3 processor parallel computer has been completed. The layout was done using the MAGIC tool and the verification using HSPICE. Suggestions for expanding the computer into a million processor network are presented. Many problems that might be encountered when implementing a massively parallel computer are discussed.

  10. 40 CFR 1065.360 - FID optimization and verification.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false FID optimization and verification....360 FID optimization and verification. (a) Scope and frequency. For all FID analyzers, calibrate the FID upon initial installation. Repeat the calibration as needed using good engineering judgment. For...

  11. Certification and verification for calmac flat plate solar collector

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-27

    This document contains information used in the certification and verification of the Calmac Flat Plate Collector. Contained are such items as test procedures and results, information on materials used, Installation, Operation, and Maintenance Manuals, and other information pertaining to the verification and certification.

  12. Grip-pattern verification for a smart gun

    NARCIS (Netherlands)

    Shang, X.; Groenland, J.P.J.; Groenland, J.P.J.; Veldhuis, Raymond N.J.

    In the biometric verification system of a smart gun, the rightful user of the gun is recognized based on grip-pattern recognition. It was found that the verification performance of grip-pattern recognition degrades strongly when the data for training and testing the classifier, respectively, have

  13. 7 CFR 983.68 - Verification of reports.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Verification of reports. 983.68 Section 983.68 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing..., ARIZONA, AND NEW MEXICO Reports, Books and Records § 983.68 Verification of reports. For the purpose...

  14. Neutron spectrometric methods for core inventory verification in research reactors

    CERN Document Server

    Ellinger, A; Hansen, W; Knorr, J; Schneider, R

    2002-01-01

    In consequence of the Non-Proliferation Treaty safeguards, inspections are periodically made in nuclear facilities by the IAEA and the EURATOM Safeguards Directorate. The inspection methods are permanently improved. Therefore, the Core Inventory Verification method is being developed as an indirect method for the verification of the core inventory and to check the declared operation of research reactors.

  15. A Tutorial on Text-Independent Speaker Verification

    Science.gov (United States)

    Bimbot, Frédéric; Bonastre, Jean-François; Fredouille, Corinne; Gravier, Guillaume; Magrin-Chagnolleau, Ivan; Meignier, Sylvain; Merlin, Teva; Ortega-García, Javier; Petrovska-Delacrétaz, Dijana; Reynolds, Douglas A.

    2004-12-01

    This paper presents an overview of a state-of-the-art text-independent speaker verification system. First, an introduction proposes a modular scheme of the training and test phases of a speaker verification system. Then, the most commonly speech parameterization used in speaker verification, namely, cepstral analysis, is detailed. Gaussian mixture modeling, which is the speaker modeling technique used in most systems, is then explained. A few speaker modeling alternatives, namely, neural networks and support vector machines, are mentioned. Normalization of scores is then explained, as this is a very important step to deal with real-world data. The evaluation of a speaker verification system is then detailed, and the detection error trade-off (DET) curve is explained. Several extensions of speaker verification are then enumerated, including speaker tracking and segmentation by speakers. Then, some applications of speaker verification are proposed, including on-site applications, remote applications, applications relative to structuring audio information, and games. Issues concerning the forensic area are then recalled, as we believe it is very important to inform people about the actual performance and limitations of speaker verification systems. This paper concludes by giving a few research trends in speaker verification for the next couple of years.

  16. A methodology for the rigorous verification of plasma simulation codes

    Science.gov (United States)

    Riva, Fabio

    2016-10-01

    The methodology used to assess the reliability of numerical simulation codes constitutes the Verification and Validation (V&V) procedure. V&V is composed by two separate tasks: the verification, which is a mathematical issue targeted to assess that the physical model is correctly solved, and the validation, which determines the consistency of the code results, and therefore of the physical model, with experimental data. In the present talk we focus our attention on the verification, which in turn is composed by the code verification, targeted to assess that a physical model is correctly implemented in a simulation code, and the solution verification, that quantifies the numerical error affecting a simulation. Bridging the gap between plasma physics and other scientific domains, we introduced for the first time in our domain a rigorous methodology for the code verification, based on the method of manufactured solutions, as well as a solution verification based on the Richardson extrapolation. This methodology was applied to GBS, a three-dimensional fluid code based on a finite difference scheme, used to investigate the plasma turbulence in basic plasma physics experiments and in the tokamak scrape-off layer. Overcoming the difficulty of dealing with a numerical method intrinsically affected by statistical noise, we have now generalized the rigorous verification methodology to simulation codes based on the particle-in-cell algorithm, which are employed to solve Vlasov equation in the investigation of a number of plasma physics phenomena.

  17. 19 CFR 10.309 - Verification of documentation.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Verification of documentation. 10.309 Section 10.309 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF... Trade Agreement § 10.309 Verification of documentation. Any evidence of country of origin or of...

  18. A Tutorial on Text-Independent Speaker Verification

    Directory of Open Access Journals (Sweden)

    Frédéric Bimbot

    2004-04-01

    Full Text Available This paper presents an overview of a state-of-the-art text-independent speaker verification system. First, an introduction proposes a modular scheme of the training and test phases of a speaker verification system. Then, the most commonly speech parameterization used in speaker verification, namely, cepstral analysis, is detailed. Gaussian mixture modeling, which is the speaker modeling technique used in most systems, is then explained. A few speaker modeling alternatives, namely, neural networks and support vector machines, are mentioned. Normalization of scores is then explained, as this is a very important step to deal with real-world data. The evaluation of a speaker verification system is then detailed, and the detection error trade-off (DET curve is explained. Several extensions of speaker verification are then enumerated, including speaker tracking and segmentation by speakers. Then, some applications of speaker verification are proposed, including on-site applications, remote applications, applications relative to structuring audio information, and games. Issues concerning the forensic area are then recalled, as we believe it is very important to inform people about the actual performance and limitations of speaker verification systems. This paper concludes by giving a few research trends in speaker verification for the next couple of years.

  19. 40 CFR 1065.920 - PEMS Calibrations and verifications.

    Science.gov (United States)

    2010-07-01

    ... by laboratory equipment as follows: (1) Mount an engine on a dynamometer for laboratory testing... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Field Testing and Portable Emission Measurement Systems § 1065... verification. The verification consists of operating an engine over a duty cycle in the laboratory...

  20. Verification of a CT scanner using a miniature step gauge

    DEFF Research Database (Denmark)

    Cantatore, Angela; Andreasen, J.L.; Carmignato, S.;

    2011-01-01

    The work deals with performance verification of a CT scanner using a 42mm miniature replica step gauge developed for optical scanner verification. Errors quantification and optimization of CT system set-up in terms of resolution and measurement accuracy are fundamental for use of CT scanning...

  1. 45 CFR 1626.7 - Verification of eligible alien status.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Verification of eligible alien status. 1626.7... CORPORATION RESTRICTIONS ON LEGAL ASSISTANCE TO ALIENS § 1626.7 Verification of eligible alien status. (a) An alien seeking representation shall submit appropriate documents to verify eligibility, unless the...

  2. Verification and optimization of a PLC control schedule

    NARCIS (Netherlands)

    Brinksma, Ed; Mader, Angelika; Fehnker, Ansgar

    2002-01-01

    We report on the use of model checking techniques for both the verification of a process control program and the derivation of optimal control schedules. Most of this work has been carried out as part of a case study for the EU VHS project (Verification of Hybrid Systems), in which the program for a

  3. Sciduction: Combining Induction, Deduction, and Structure for Verification and Synthesis

    OpenAIRE

    Seshia, Sanjit A.

    2012-01-01

    Even with impressive advances in automated formal methods, certain problems in system verification and synthesis remain challenging. Examples include the verification of quantitative properties of software involving constraints on timing and energy consumption, and the automatic synthesis of systems from specifications. The major challenges include environment modeling, incompleteness in specifications, and the complexity of underlying decision problems. This position paper proposes sciductio...

  4. 20 CFR 211.15 - Verification of compensation claimed.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Verification of compensation claimed. 211.15... CREDITABLE RAILROAD COMPENSATION § 211.15 Verification of compensation claimed. Compensation claimed by an... Board before it may be credited. An employee's claim to compensation not credited shall be processed...

  5. SPR Hydrostatic Column Model Verification and Validation.

    Energy Technology Data Exchange (ETDEWEB)

    Bettin, Giorgia [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lord, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rudeen, David Keith [Gram, Inc. Albuquerque, NM (United States)

    2015-10-01

    A Hydrostatic Column Model (HCM) was developed to help differentiate between normal "tight" well behavior and small-leak behavior under nitrogen for testing the pressure integrity of crude oil storage wells at the U.S. Strategic Petroleum Reserve. This effort was motivated by steady, yet distinct, pressure behavior of a series of Big Hill caverns that have been placed under nitrogen for extended period of time. This report describes the HCM model, its functional requirements, the model structure and the verification and validation process. Different modes of operation are also described, which illustrate how the software can be used to model extended nitrogen monitoring and Mechanical Integrity Tests by predicting wellhead pressures along with nitrogen interface movements. Model verification has shown that the program runs correctly and it is implemented as intended. The cavern BH101 long term nitrogen test was used to validate the model which showed very good agreement with measured data. This supports the claim that the model is, in fact, capturing the relevant physical phenomena and can be used to make accurate predictions of both wellhead pressure and interface movements.

  6. Comparison of particulate verification techniques study

    Science.gov (United States)

    Rivera, Rachel

    2006-08-01

    The efficacy of five particulate verification techniques on four types of materials was studied. Statistical Analysis Software/JMP 6.0 was used to create a statistically valid design of experiments. In doing so, 35 witness coupons consisting of the four types of materials being studied, were intentionally contaminated with particulate fallout. Image Analysis was used to characterize the extent of particulate fallout on the coupons and was used to establish a baseline, or basis of comparison, against the five techniques that were studied. The five particulate verification techniques were the Tapelift, the Particulate Solvent Rinse, the GelPak lift, an in-line vacuum filtration probe, and the Infinity Focusing Microscope (IFM). The four types of materials consisted of magnesium flouride (MgF II) coated mirrors, composite coated silver aluminum (CCAg), Z93 and NS43G coated aluminum, and silicon (si) wafers. The vacuum probe was determined to be most effective for Z93, the tapelift or vacuum probe for MgF2, and the GelPak Lift for CCAg and si substrates. A margin of error for each technique, based on experimental data from two experiments, for si wafer substrates, yielded the following: Tapelift - 67%, Solvent Rinse - 58%, GelPak- 26%, Vacuum Probe - 93%, IFM-to be determined.

  7. Toward the Verification of a Simple Hypervisor

    Directory of Open Access Journals (Sweden)

    Mike Dahlin

    2011-10-01

    Full Text Available Virtualization promises significant benefits in security, efficiency, dependability, and cost. Achieving these benefits depends upon the reliability of the underlying virtual machine monitors (hypervisors. This paper describes an ongoing project to develop and verify MinVisor, a simple but functional Type-I x86 hypervisor, proving protection properties at the assembly level using ACL2. Originally based on an existing research hypervisor, MinVisor provides protection of its own memory from a malicious guest. Our long-term goal is to fully verify MinVisor, providing a vehicle to investigate the modeling and verification of hypervisors at the implementation level, and also a basis for further systems research. Functional segments of the MinVisor C code base are translated into Y86 assembly, and verified with respect to the Y86 model. The inductive assertions (also known as "compositional cutpoints" methodology is used to prove the correctness of the code. The proof of the code that sets up the nested page tables is described. We compare this project to related efforts in systems code verification and outline some useful steps forward.

  8. CTBT integrated verification system evaluation model supplement

    Energy Technology Data Exchange (ETDEWEB)

    EDENBURN,MICHAEL W.; BUNTING,MARCUS; PAYNE JR.,ARTHUR C.; TROST,LAWRENCE C.

    2000-03-02

    Sandia National Laboratories has developed a computer based model called IVSEM (Integrated Verification System Evaluation Model) to estimate the performance of a nuclear detonation monitoring system. The IVSEM project was initiated in June 1994, by Sandia's Monitoring Systems and Technology Center and has been funded by the U.S. Department of Energy's Office of Nonproliferation and National Security (DOE/NN). IVSEM is a simple, ''top-level,'' modeling tool which estimates the performance of a Comprehensive Nuclear Test Ban Treaty (CTBT) monitoring system and can help explore the impact of various sensor system concepts and technology advancements on CTBT monitoring. One of IVSEM's unique features is that it integrates results from the various CTBT sensor technologies (seismic, in sound, radionuclide, and hydroacoustic) and allows the user to investigate synergy among the technologies. Specifically, IVSEM estimates the detection effectiveness (probability of detection), location accuracy, and identification capability of the integrated system and of each technology subsystem individually. The model attempts to accurately estimate the monitoring system's performance at medium interfaces (air-land, air-water) and for some evasive testing methods such as seismic decoupling. The original IVSEM report, CTBT Integrated Verification System Evaluation Model, SAND97-25 18, described version 1.2 of IVSEM. This report describes the changes made to IVSEM version 1.2 and the addition of identification capability estimates that have been incorporated into IVSEM version 2.0.

  9. CTBT integrated verification system evaluation model supplement

    Energy Technology Data Exchange (ETDEWEB)

    EDENBURN,MICHAEL W.; BUNTING,MARCUS; PAYNE JR.,ARTHUR C.; TROST,LAWRENCE C.

    2000-03-02

    Sandia National Laboratories has developed a computer based model called IVSEM (Integrated Verification System Evaluation Model) to estimate the performance of a nuclear detonation monitoring system. The IVSEM project was initiated in June 1994, by Sandia's Monitoring Systems and Technology Center and has been funded by the U.S. Department of Energy's Office of Nonproliferation and National Security (DOE/NN). IVSEM is a simple, ''top-level,'' modeling tool which estimates the performance of a Comprehensive Nuclear Test Ban Treaty (CTBT) monitoring system and can help explore the impact of various sensor system concepts and technology advancements on CTBT monitoring. One of IVSEM's unique features is that it integrates results from the various CTBT sensor technologies (seismic, in sound, radionuclide, and hydroacoustic) and allows the user to investigate synergy among the technologies. Specifically, IVSEM estimates the detection effectiveness (probability of detection), location accuracy, and identification capability of the integrated system and of each technology subsystem individually. The model attempts to accurately estimate the monitoring system's performance at medium interfaces (air-land, air-water) and for some evasive testing methods such as seismic decoupling. The original IVSEM report, CTBT Integrated Verification System Evaluation Model, SAND97-25 18, described version 1.2 of IVSEM. This report describes the changes made to IVSEM version 1.2 and the addition of identification capability estimates that have been incorporated into IVSEM version 2.0.

  10. Bayesian online compressed sensing

    Science.gov (United States)

    Rossi, Paulo V.; Kabashima, Yoshiyuki; Inoue, Jun-ichi

    2016-08-01

    In this paper, we explore the possibilities and limitations of recovering sparse signals in an online fashion. Employing a mean field approximation to the Bayes recursion formula yields an online signal recovery algorithm that can be performed with a computational cost that is linearly proportional to the signal length per update. Analysis of the resulting algorithm indicates that the online algorithm asymptotically saturates the optimal performance limit achieved by the offline method in the presence of Gaussian measurement noise, while differences in the allowable computational costs may result in fundamental gaps of the achievable performance in the absence of noise.

  11. Unwanted online sexual solicitation and online sexual risk behavior

    NARCIS (Netherlands)

    Baumgartner, S.E.; Valkenburg, P.M.; Peter, J.; Yan, Z.

    2012-01-01

    In recent years, there have been growing concerns about online sexual solicitations and online sexual risk behaviors. Recent studies suggest that only a minority of adolescents is confronted with online sexual solicitations or engages in online sexual risk behavior. Whereas more girls encounter

  12. Automatic Verification of Parametric Specifications with Complex Topologies

    CERN Document Server

    Faber, Johannes; Jacobs, Swen; Sofronie-Stokkermans, Viorica

    2010-01-01

    The focus of this paper is on reducing the complexity in verification by exploiting modularity at various levels: in specification, in verification, and structurally. For specifications, we use the modular language CSP-OZ-DC, which allows us to decouple verification tasks concerning data from those concerning durations. At the verification level, we exploit modularity in theorem proving for rich data structures and use this for invariant checking. At the structural level, we analyze possibilities for modular verification of systems consisting of various components which interact.We illustrate these ideas by automatically verifying safety properties of a case study from the European Train Control System standard, which extends previous examples by comprising a complex track topology with lists of track segments and trains with different routes.

  13. Simulation Environment Based on the Universal Verification Methodology

    CERN Document Server

    Fiergolski, Adrian

    2016-01-01

    Universal Verification Methodology (UVM) is a standardized approach of verifying integrated circuit designs, targeting a Coverage-Driven Verification (CDV). It combines automatic test generation, self-checking testbenches, and coverage metrics to indicate progress in the design verification. The flow of the CDV differs from the traditional directed-testing approach. With the CDV, a testbench developer, by setting the verification goals, starts with an structured plan. Those goals are targeted further by a developed testbench, which generates legal stimuli and sends them to a device under test (DUT). The progress is measured by coverage monitors added to the simulation environment. In this way, the non-exercised functionality can be identified. Moreover, the additional scoreboards indicate undesired DUT behaviour. Such verification environments were developed for three recent ASIC and FPGA projects which have successfully implemented the new work-flow: (1) the CLICpix2 65 nm CMOS hybrid pixel readout ASIC desi...

  14. Approaches to verification of two-dimensional water quality models

    Energy Technology Data Exchange (ETDEWEB)

    Butkus, S.R. (Tennessee Valley Authority, Chattanooga, TN (USA). Water Quality Dept.)

    1990-11-01

    The verification of a water quality model is the one procedure most needed by decision making evaluating a model predictions, but is often not adequate or done at all. The results of a properly conducted verification provide the decision makers with an estimate of the uncertainty associated with model predictions. Several statistical tests are available for quantifying of the performance of a model. Six methods of verification were evaluated using an application of the BETTER two-dimensional water quality model for Chickamauga reservoir. Model predictions for ten state variables were compared to observed conditions from 1989. Spatial distributions of the verification measures showed the model predictions were generally adequate, except at a few specific locations in the reservoir. The most useful statistics were the mean standard error of the residuals. Quantifiable measures of model performance should be calculated during calibration and verification of future applications of the BETTER model. 25 refs., 5 figs., 7 tabs.

  15. A Formal Verification Methodology for Checking Data Integrity

    CERN Document Server

    Umezawa, Yasushi

    2011-01-01

    Formal verification techniques have been playing an important role in pre-silicon validation processes. One of the most important points considered in performing formal verification is to define good verification scopes; we should define clearly what to be verified formally upon designs under tests. We considered the following three practical requirements when we defined the scope of formal verification. They are (a) hard to verify (b) small to handle, and (c) easy to understand. Our novel approach is to break down generic properties for system into stereotype properties in block level and to define requirements for Verifiable RTL. Consequently, each designer instead of verification experts can describe properties of the design easily, and formal model checking can be applied systematically and thoroughly to all the leaf modules. During the development of a component chip for server platforms, we focused on RAS (Reliability, Availability, and Serviceability) features and described more than 2000 properties in...

  16. Simulation Environment Based on the Universal Verification Methodology

    CERN Document Server

    AUTHOR|(SzGeCERN)697338

    2016-01-01

    Universal Verification Methodology (UVM) is a standardized approach of verifying integrated circuit designs, targeting a Coverage-Driven Verification (CDV). It combines automatic test generation, self-checking testbenches, and coverage metrics to indicate progress in the design verification. The flow of the CDV differs from the traditional directed-testing approach. With the CDV, a testbench developer, by setting the verification goals, starts with an structured plan. Those goals are targeted further by a developed testbench, which generates legal stimuli and sends them to a device under test (DUT). The progress is measured by coverage monitors added to the simulation environment. In this way, the non-exercised functionality can be identified. Moreover, the additional scoreboards indicate undesired DUT behaviour. Such verification environments were developed for three recent ASIC and FPGA projects which have successfully implemented the new work-flow: (1) the CLICpix2 65 nm CMOS hybrid pixel readout ASIC desi...

  17. Assessment of a 2D electronic portal imaging devices-based dosimetry algorithm for pretreatment and in-vivo midplane dose verification

    Directory of Open Access Journals (Sweden)

    Ali Jomehzadeh

    2016-01-01

    Conclusion: The 2D EPID-based dosimetry algorithm provides an accurate method to verify the dose of a simple 10 × 10 cm2 field, in two dimensions, inside a homogenous slab phantom and an IMRT prostate plan, as well as in 3D conformal plans (prostate, head-and-neck, and lung plans applied using an anthropomorphic phantom and in vivo. However, further investigation to improve the 2D EPID dosimetry algorithm for a head-and-neck case, is necessary.

  18. Precise On-line Position Measurement for Particle Therapy

    CERN Document Server

    Actis, O; König, S

    2014-01-01

    An on-line beam position monitoring and regular beam stability tests are of utmost importance for the Quality Assurance (QA) of the patient treatment at any particle therapy facility. The Gantry${0.5 mm}2$ at the Paul Scherrer Institute uses a strip ionization chamber for the on-line beam position verification. The design of the strip chamber placed in the beam in front of the patient allows for a small beam penumbra in order to achieve a high-quality lateral beam delivery. The detector granularity and the low noise allow the reconstruction of the signals offered by Gantry${0.5 mm}2$ with a precision of about 0.1 mm. The frond-end electronics and the whole data processing sequence have been optimized for minimizing the dead time between the beam applications to about 2 ms: the charge collection is performed in about 1 ms, read-out takes place in 100 $\\mu$s while data verification and logging are completed in less than 1 ms. The sub-millimeter precision of the lateral reconstruction allows the dose inhomogenei...

  19. Classification and Verification of Handwritten Signatures with Time Causal Information Theory Quantifiers.

    Science.gov (United States)

    Rosso, Osvaldo A; Ospina, Raydonal; Frery, Alejandro C

    2016-01-01

    We present a new approach for handwritten signature classification and verification based on descriptors stemming from time causal information theory. The proposal uses the Shannon entropy, the statistical complexity, and the Fisher information evaluated over the Bandt and Pompe symbolization of the horizontal and vertical coordinates of signatures. These six features are easy and fast to compute, and they are the input to an One-Class Support Vector Machine classifier. The results are better than state-of-the-art online techniques that employ higher-dimensional feature spaces which often require specialized software and hardware. We assess the consistency of our proposal with respect to the size of the training sample, and we also use it to classify the signatures into meaningful groups.

  20. Runtime Verification in Context : Can Optimizing Error Detection Improve Fault Diagnosis

    Science.gov (United States)

    Dwyer, Matthew B.; Purandare, Rahul; Person, Suzette

    2010-01-01

    Runtime verification has primarily been developed and evaluated as a means of enriching the software testing process. While many researchers have pointed to its potential applicability in online approaches to software fault tolerance, there has been a dearth of work exploring the details of how that might be accomplished. In this paper, we describe how a component-oriented approach to software health management exposes the connections between program execution, error detection, fault diagnosis, and recovery. We identify both research challenges and opportunities in exploiting those connections. Specifically, we describe how recent approaches to reducing the overhead of runtime monitoring aimed at error detection might be adapted to reduce the overhead and improve the effectiveness of fault diagnosis.