The Challenge of Detection and Diagnosis of Fugacious Hardware Faults in VLSI Designs

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-38789-0_7Current integration scales are increasing the number and types of faults that embedded systems must face. Traditional approaches focus on dealing with those transient and permanent faults that impact the state or output of systems, whereas little research has targeted those faults being logically, electrically or temporally masked -which we have named fugacious. A fast detection and precise diagnosis of faults occurrence, even if the provided service is unaffected, could be of invaluable help to determine, for instance, that systems are currently under the influence of environmental disturbances like radiation, suffering from wear-out, or being affected by an intermittent fault. Upon detection, systems may react to adapt the deployed fault tolerance mechanisms to the diagnosed problem. This paper explores these ideas evaluating challenges and requirements involved, and provides an outline of potential techniques to be applied.This work has been funded by Spanish Ministry of Economy ARENES project (TIN2012-38308-C02-01)Espinosa García, J.; Andrés Martínez, DD.; Ruiz, JC.; Gil, P. (2013). The Challenge of Detection and Diagnosis of Fugacious Hardware Faults in VLSI Designs. En Dependable Computing. Springer. 76-87. https://doi.org/10.1007/978-3-642-38789-0_7S7687Narayanan, V., Xie, Y.: Reliability concerns in embedded systems design. IEEE Computer 1(39), 118–120 (2006)Hannius, O., Karlsson, J.: Impact of soft errors in a jet engine controller. In: Ortmeier, F., Daniel, P. (eds.) SAFECOMP 2012. LNCS, vol. 7612, pp. 223–234. Springer, Heidelberg (2012)Borkar, S.: Designing reliable systems from unreliable components: the challenges of transistor variability and degradation. IEEE Micro 25(6), 10–16 (2005)JEDEC: Measurement and reporting of alpha particle and terrestrial cosmic ray-induced soft errors in semiconductor devices. JEDEC Standard JESD89A. JEDEC (2006)Gracia-Moran, J., Gil-Tomas, D., Saiz-Adalid, L.J., Baraza, J.C., Gil-Vicente, P.J.: Experimental validation of a fault tolerant microcomputer system against intermittent faults. In: DSN, pp. 413–418 (2010)Constantinescu, C.: Intermittent faults and effects on reliability of integrated circuits. In: Proceedings of the 2008 Annual Reliability and Maintainability Symposium, pp. 370–374. IEEE Computer Society, Washington, DC (2008)Avizienis, A., Laprie, J.C., Randell, B., Landwehr, C.: Basic concepts and taxonomy of dependable and secure computing. IEEE Trans. Dependable Secur. Comput. 1, 11–33 (2004)Johnson, C., Holloway, C.: The dangers of failure masking in fault-tolerant software: Aspects of a recent in-flight upset event. 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Low-Dose Imaging in a New Preclinical Total-Body PET/CT Scanner.

Ionizing radiation constitutes a health risk to imaging scientists and study animals. Both PET and CT produce ionizing radiation. CT doses in pre-clinical in vivo imaging typically range from 50 to 1,000 mGy and biological effects in mice at this dose range have been previously described. [ <sup>18</sup> F]FDG body doses in mice have been estimated to be in the range of 100 mGy for [ <sup>18</sup> F]FDG. Yearly, the average whole body doses due to handling of activity by PET technologists are reported to be 3-8 mSv. A preclinical PET/CT system is presented with design features which make it suitable for small animal low-dose imaging. The CT subsystem uses a X-source power that is optimized for small animal imaging. The system design incorporates a spatial beam shaper coupled with a highly sensitive flat-panel detector and very fast acquisition (<10 s) which allows for whole body scans with doses as low as 3 mGy. The mouse total-body PET subsystem uses a detector architecture based on continuous crystals, coupled to SiPM arrays and a readout based in rows and columns. The PET field of view is 150 mm axial and 80 mm transaxial. The high solid-angle coverage of the sample and the use of continuous crystals achieve a sensitivity of 9% (NEMA) that can be leveraged for use of low tracer doses and/or performing rapid scans. The low-dose imaging capabilities of the total-body PET subsystem were tested with NEMA phantoms, in tumor models, a mouse bone metabolism scan and a rat heart dynamic scan. The CT imaging capabilities were tested in mice and in a low contrast phantom. The PET low-dose phantom and animal experiments provide evidence that image quality suitable for preclinical PET studies is achieved. Furthermore, CT image contrast using low dose scan settings was suitable as a reference for PET scans. Total-body mouse PET/CT studies could be completed with total doses of <10 mGy

Implementation and analysis of list mode algorithm using tubes of response on a dedicated brain and breast PET

In this work we present an innovative algorithm for the reconstruction of PET images based on the List-Mode (LM) technique which improves their spatial resolution compared to results obtained with current MLEM algorithms. This study appears as a part of a large project with the aim of improving diagnosis in early Alzheimer disease stages by means of a newly developed hybrid PET-MR insert. At the present, Alzheimer is the most relevant neurodegenerative disease and the best way to apply an effective treatment is its early diagnosis. The PET device will consist of several monolithic LYSO crystals coupled to SiPM detectors. Monolithic crystals can reduce scanner costs with the advantage to enable implementation of very small virtual pixels in their geometry. This is especially useful for LM reconstruction algorithms, since they do not need a pre-calculated system matrix. We have developed an LM algorithm which has been initially tested with a large aperture (186 mm) breast PET system. Such an algorithm instead of using the common lines of response, incorporates a novel calculation of tubes of response. The new approach improves the volumetric spatial resolution about a factor 2 at the border of the field of view when compared with traditionally used MLEM algorithm. Moreover, it has also shown to decrease the image noise, thus increasing the image quality. © 2012 Elsevier B.V. All rights reserved.This work was supported by the Centre for Industrial Technological Development co-funded by FEDER through the Technology Fund (DREAM Project, IDI-20110718), by the Spanish Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I+D+I) under Grant. No. FIS2010-21216-CO2-01TEO 2008/114.Moliner Martínez, L.; Correcher, C.; González Martínez, AJ.; Conde Castellanos, PE.; Hernández Hernández, L.; Orero Palomares, A.; Rodríguez Álvarez, MJ.... (2013). Implementation and analysis of list mode algorithm using tubes of response on a dedicated brain and breast PET. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 702:129-132. https://doi.org/10.1016/j.nima.2012.08.029S12913270

Uncertainty on radiation doses estimated by biological and retrospective physical methods

Biological and physical retrospective dosimetry are recognised as key techniques to provide individual estimates of dose following unplanned exposures to ionising radiation. Whilst there has been a relatively large amount of recent development in the biological and physical procedures, development of statistical analysis techniques has failed to keep pace. The aim of this paper is to review the current state of the art in uncertainty analysis techniques across the ‘EURADOS Working Group 10— Retrospective dosimetry’ members, to give concrete examples of implementation of the techniques recommended in the international standards, and to further promote the use of Monte Carlo techniques to support characterisation of uncertainties. It is concluded that sufficient techniques are available and in use by most laboratories for acute, whole body exposures to highly penetrating radiation, but further work will be required to ensure that statistical analysis is always wholly sufficient for the more complex exposure scenarios

Strategies of statistical windows in PET image reconstruction to improve the user s real time experience

[EN] Nowadays, with the increase of the computational power of modern computers together with the state-of-the-art reconstruction algorithms, it is possible to obtain Positron Emission Tomography (PET) images in practically real time. These facts open the door to new applications such as radio-pharmaceuticals tracking inside the body or the use of PET for image-guided procedures, such as biopsy interventions, among others. This work is a proof of concept that aims to improve the user experience with real time PET images. Fixed, incremental, overlapping, sliding and hybrid windows are the different statistical combinations of data blocks used to generate intermediate images in order to follow the path of the activity in the Field Of View (FOV). To evaluate these different combinations, a point source is placed in a dedicated breast PET device and moved along the FOV. These acquisitions are reconstructed according to the different statistical windows, resulting in a smoother transition of positions for the image reconstructions that use the sliding and hybrid window.This study has been realized in the context of the European Union's Seventh Framework Programme for research. L. Moliner was financed with VALi+d program grant.Moliner Martínez, L.; Correcher Salvador, C.; Giménez-Alventosa, V.; Ilisie, V.; Álvarez-Gómez, JM.; Sánchez Góez, S.; Rodríguez-Álvarez, M. (2017). Strategies of statistical windows in PET image reconstruction to improve the user s real time experience. Journal of Physics: Conference Series (Online). 931:1-4. https://doi.org/10.1088/1742-6596/931/1/012025S1493

The MINDVIEW project: First results

[EN] We present the first results of the MINDVIEW project. An innovative imaging system for the human brain examination, allowing simultaneous acquisition of PET/MRI images, has been designed and constructed. It consists of a high sensitivity and high resolution PET scanner integrated in a novel, head-dedicated, radio frequency coil for a 3T MRI scanner. Preliminary measurements from the PET scanner show sensitivity 3 times higher than state-of-the-art PET systems that will allow safe repeated studies on the same patient. The achieved spatial resolution, close to 1 mm, will enable differentiation of relevant brain structures for schizophrenia. A cost-effective and simple method of radiopharmaceutical production from C-11-carbon monoxide and a mini-clean room has been demonstrated. It has been shown that C-11-raclopride has higher binding potential in a new VAAT null mutant mouse model of schizophrenia compared to wild type control animals. A significant reduction in TSPO binding has been found in gray matter in a small sample of drug-naive, first episode psychosis patients, suggesting a reduced number or an altered function of immune cells in brain at early stage schizophrenia. (c) 2018 Elsevier Masson SAS. All rights reserved.This project is funded by EU grant FP7-HEALTH-F2-2013-603002.Benlloch Baviera, JM.; González Martínez, AJ.; Pani, R.; Preziosi, E.; Jackson, C.; Murphy, J.; Barbera Ballester, J.... (2018). The MINDVIEW project: First results. European Psychiatry. 50:21-27. https://doi.org/10.1016/j.eurpsy.2018.01.002S212750Gonzalez, A. J., Gonzalez-Montoro, A., Aguilar, A., Conde, P., Canizares, G., Hernandez, L., … Benlloch, J. M. (2016). A brain PET insert MR compatible: Final design and first results. 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD). doi:10.1109/nssmic.2016.8069619Dahl, K., Schou, M., Ulin, J., Sjöberg, C.-O., Farde, L., & Halldin, C. (2015). 11C-carbonylation reactions using gas–liquid segmented microfluidics. RSC Advances, 5(108), 88886-88889. doi:10.1039/c5ra20646d[26] Långström B and Sjöberg CO, System for controlling environment in reaction box, From PCT Int. Appl. (2013), WO 2013103312 A1 20130711.Autret, A., Bert, J., Strauss, O., & Visvikis, D. (2012). Projector with realistic detector scatter modelling for PET list-mode reconstruction. 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC). doi:10.1109/nssmic.2012.6551759[10] Young JW Head and Face Antropometry of Adult U.S. Citizens, Civil Aeromedical Institute, Federal Aviation Administration, U.S. Department of Transportation, Report number DOT/FAA/AM-93/10, July 1993.Braff, D. L. (1990). Sensorimotor Gating and Schizophrenia. Archives of General Psychiatry, 47(2), 181. doi:10.1001/archpsyc.1990.01810140081011Preziosi, E., Sánchez, S., González, A. J., Pani, R., Borrazzo, C., Bettiol, M., … Benlloch, J. M. (2016). Performance study of a PET scanner based on monolithic scintillators for different DoI-dependent methods. Journal of Instrumentation, 11(12), C12076-C12076. doi:10.1088/1748-0221/11/12/c12076Howes, O., McCutcheon, R., & Stone, J. (2015). Glutamate and dopamine in schizophrenia: An update for the 21st century. Journal of Psychopharmacology, 29(2), 97-115. doi:10.1177/0269881114563634Moliner, L., Correcher, C., González, A. J., Conde, P., Hernández, L., Orero, A., … Benlloch, J. M. (2013). Implementation and analysis of list mode algorithm using tubes of response on a dedicated brain and breast PET. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 702, 129-132. doi:10.1016/j.nima.2012.08.029Zelano, J., Mikulovic, S., Patra, K., Kühnemund, M., Larhammar, M., Emilsson, L., … Kullander, K. (2013). The synaptic protein encoded by the gene Slc10A4 suppresses epileptiform activity and regulates sensitivity to cholinergic chemoconvulsants. Experimental Neurology, 239, 73-81. doi:10.1016/j.expneurol.2012.09.006Antich, P., Malakhov, N., Parkey, R., Slavin, N., & Tsyganov, E. (2002). 3D position readout from thick scintillators. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 480(2-3), 782-787. doi:10.1016/s0168-9002(01)01214-1Gonzalez-Montoro, A., Benlloch, J. M., Gonzalez, A. J., Aguilar, A., Canizares, G., Conde, P., … Sanchez, F. (2017). Performance Study of a Large Monolithic LYSO PET Detector With Accurate Photon DOI Using Retroreflector Layers. IEEE Transactions on Radiation and Plasma Medical Sciences, 1(3), 229-237. doi:10.1109/trpms.2017.2692819Rahman, O., Takano, A., Amini, N., Dahl, K., Kanegawa, N., Långström, B., … Halldin, C. (2015). Synthesis of ([11C]carbonyl)raclopride and a comparison with ([11C]methyl)raclopride in a monkey PET study. Nuclear Medicine and Biology, 42(11), 893-898. doi:10.1016/j.nucmedbio.2015.07.003Howes, O. D., Kambeitz, J., Kim, E., Stahl, D., Slifstein, M., Abi-Dargham, A., & Kapur, S. (2012). The Nature of Dopamine Dysfunction in Schizophrenia and What This Means for Treatment. Archives of General Psychiatry, 69(8). doi:10.1001/archgenpsychiatry.2012.169Ling, T., Lewellen, T. K., & Miyaoka, R. S. (2007). Depth of interaction decoding of a continuous crystal detector module. Physics in Medicine and Biology, 52(8), 2213-2228. doi:10.1088/0031-9155/52/8/012González, A. J., Majewski, S., Sánchez, F., Aussenhofer, S., Aguilar, A., Conde, P., … Benlloch, J. M. (2016). The MINDView brain PET detector, feasibility study based on SiPM arrays. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 818, 82-90. doi:10.1016/j.nima.2016.02.046Wong, D. F., Waterhouse, R., Kuwabara, H., Kim, J., Brasic, J. R., Chamroonrat, W., … Mozley, P. D. (2013). 18F-FPEB, a PET Radiopharmaceutical for Quantifying Metabotropic Glutamate 5 Receptors: A First-in-Human Study of Radiochemical Safety, Biokinetics, and Radiation Dosimetry. Journal of Nuclear Medicine, 54(3), 388-396. doi:10.2967/jnumed.112.107995Jackson, C., O’Neill, K., Wall, L., & McGarvey, B. (2014). High-volume silicon photomultiplier production, performance, and reliability. Optical Engineering, 53(8), 081909. doi:10.1117/1.oe.53.8.081909Rahman, O., Långström, B., & Halldin, C. (2016). Alkyl Iodides and [11 C]CO in Nickel-Mediated Cross-Coupling Reactions: Successful Use of Alkyl Electrophiles containing a β Hydrogen Atom in Metal-Mediated [11 C]Carbonylation. ChemistrySelect, 1(10), 2498-2501. doi:10.1002/slct.201600643Sullivan, J. M., Lim, K., Labaree, D., Lin, S., McCarthy, T. J., Seibyl, J. P., … Morris, E. D. (2012). Kinetic Analysis of the Metabotropic Glutamate Subtype 5 Tracer [18F]FPEB in Bolus and Bolus-Plus-Constant-Infusion Studies in Humans. Journal of Cerebral Blood Flow & Metabolism, 33(4), 532-541. doi:10.1038/jcbfm.2012.195Levin, C. S. (2003). Detector design issues for compact nuclear emission cameras dedicated to breast imaging. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 497(1), 60-74. doi:10.1016/s0168-9002(02)01893-4Larhammar, M., Patra, K., Blunder, M., Emilsson, L., Peuckert, C., Arvidsson, E., … Kullander, K. (2015). SLC10A4 Is a Vesicular Amine-Associated Transporter Modulating Dopamine Homeostasis. Biological Psychiatry, 77(6), 526-536. doi:10.1016/j.biopsych.2014.07.017Kaul, M., Surti, S., & Karp, J. S. (2013). Combining Surface Treatments With Shallow Slots to Improve the Spatial Resolution Performance of Continuous, Thick LYSO Detectors for PET. IEEE Transactions on Nuclear Science, 60(1), 44-52. doi:10.1109/tns.2013.2240315Bleich, A., Brown, S.-L., Kahn, R., & van Praag, H. M. (1988). The Role of Serotonin in Schizophrenia. Schizophrenia Bulletin, 14(2), 297-315. doi:10.1093/schbul/14.2.29

ALBIRA: A small animal PET/SPECT/CT imaging system

Purpose: The authors have developed a trimodal PET/SPECT/CT scanner for small animal imaging. The gamma ray subsystems are based on monolithic crystals coupled to multianode photomultiplier tubes (MA-PMTs), while computed tomography (CT) comprises a commercially available microfocus x-ray tube and a CsI scintillator 2D pixelated flat panel x-ray detector. In this study the authors will report on the design and performance evaluation of the multimodal system. Methods: X-ray transmission measurements are performed based on cone-beam geometry. Individual projections were acquired by rotating the x-ray tube and the 2D flat panel detector, thus making possible a transaxial field of view (FOV) of roughly 80 mm in diameter and an axial FOV of 65 mm for the CT system. The single photon emission computed tomography (SPECT) component has a dual head detector geometry mounted on a rotating gantry. The distance between the SPECT module detectors can be varied in order to optimize specific user requirements, including variable FOV. The positron emission tomography (PET) system is made up of eight compact modules forming an octagon with an axial FOV of 40 mm and a transaxial FOV of 80 mm in diameter. The main CT image quality parameters (spatial resolution and uniformity) have been determined. In the case of the SPECT, the tomographic spatial resolution and system sensitivity have been evaluated with a99mTc solution using single-pinhole and multi-pinhole collimators. PET and SPECT images were reconstructed using three-dimensional (3D) maximum likelihood and ordered subset expectation maximization (MLEM and OSEM) algorithms developed by the authors, whereas the CT images were obtained using a 3D based FBP algorithm. Results: CT spatial resolution was 85μm while a uniformity of 2.7% was obtained for a water filled phantom at 45 kV. The SPECT spatial resolution was better than 0.8 mm measured with a Derenzo-like phantom for a FOV of 20 mm using a 1-mm pinhole aperture collimator. The full width at half-maximum PET radial spatial resolution at the center of the field of view was 1.55 mm. The SPECT system sensitivity for a FOV of 20 mm and 15% energy window was 700 cps/MBq (7.8 × 10−2%) using a multi-pinhole equipped with five apertures 1 mm in diameter, whereas the PET absolute sensitivity was 2% for a 350–650 keV energy window and a 5 ns timing window. Several animal images are also presented. Conclusions: The new small animal PET/SPECT/CT proposed here exhibits high performance, producing high-quality images suitable for studies with small animals. Monolithic design for PET and SPECT scintillator crystals reduces cost and complexity without significant performance degradation.This study was supported by the Spanish Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I+D+I) under Grant No. FIS2010-21216-CO2-01 and Valencian Local Government under Grant PROMETEO 2008/114. The authors also thank Brennan Holt for checking and correcting the text.Sánchez Martínez, F.; Orero Palomares, A.; Soriano Asensi, A.; Correcher Salvador, C.; Conde Castellanos, PE.; González Martínez, AJ.; Hernández Hernández, L.... (2013). ALBIRA: A small animal PET/SPECT/CT imaging system. Medical Physics. 40(5):5190601-5190611. https://doi.org/10.1118/1.4800798S5190601519061140

Time reconstruction study using tubes of response backprojectors in List Mode algorithms, applied to amonolithic crystals based breast PET

[Otros] The LM-EM algorithm has the advantage to calculate the emission probabilities needed for the reconstruction process on the fly, without the need of a pre-calculated system matrix. The reconstruction time for this algorithm strongly depends on the used backprojector and the available statistics. This algorithm when implemented in systems using monolithic crystals to detect gamma radiation allows one to extensively exploit the virtual pixilation feature, not available for systems based on pixilated crystals. In this work we present a backprojector for LM-EM, the TOR method, which achieves a tradeoff between computational efficiency and image quality. Its temporal subset algorithm optimization (LM-OS) has also been implemented in order to achieve real-time reconstructions. To evaluate the performances of LM-OS algorithm with the TOR method backprojector and only with one iteration on the datasets, studies based on the system spatial resolution, uniformity, and contrast coefficients were carried out and they were compared with those obtained with LM-EM and MLEM algorithms using twelve iteration. Finally, a study on reconstruction time using LM-OS has been performed with breast patients dataProject funded by the Spanish Ministry of Economy and Competitiveness and co-funded with FEDER's funds within the INNPACTO 2011 program. This work was supported by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+i) under Grant No. FIS2010-21216-CO2-01 and the Valencian Local Government under Grants PROMETEOII/2013/010 and ISIC 2011/013Moliner, L.; Correcher, C.; González Martínez, AJ.; Conde, P.; Crespo, E.; Hernandez, L.; Rigla, JP.... (2013). Time reconstruction study using tubes of response backprojectors in List Mode algorithms, applied to amonolithic crystals based breast PET. IEEE. 14-18. https://doi.org/10.1109/NSSMIC.2013.6829372S141