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The Conference focuses on all aspects of instrumentation and measurement science andtechnology research development and applications. The list of program topics includes but isnot limited to: Measurement Science & Education, Measurement Systems, Measurement DataAcquisition, Measurements of Physical Quantities, and Measurement Applications.
The conference program will consist of plenary lectures, symposia, workshops andinvitedsessions of the latest significant findings and developments in all the major fields ofbiomedical engineering.Submitted papers will be peer reviewed. Accepted high quality paperswill be presented in oral and postersessions, will appear in the Conference Proceedings and willbe indexed in PubMed/MEDLINE & IEEE Xplore
The IEEE International Symposium on Biomedical Imaging (ISBI) is the premier forum for the presentation of technological advances in theoretical and applied biomedical imaging.ISBI 2019 will be the 16th meeting in this series. The previous meetings have played a leading role in facilitating interaction between researchers in medical and biological imaging. The 2019 meeting will continue this tradition of fostering cross fertilization among different imaging communities and contributing to an integrative approach to biomedical imaging across all scales of observation.
Photovoltaic materials, devices, systems and related science and technology
2019 IEEE 69th Electronic Components and Technology Conference (ECTC)
premier components, packaging and technology conference
Contains articles on the applications and other relevant technology. Electronic applications include analog and digital circuits employing thin films and active devices such as Josephson junctions. Power applications include magnet design as well asmotors, generators, and power transmission
Broad coverage of concepts and methods of the physical and engineering sciences applied in biology and medicine, ranging from formalized mathematical theory through experimental science and technological development to practical clinical applications.
Computer, the flagship publication of the IEEE Computer Society, publishes peer-reviewed technical content that covers all aspects of computer science, computer engineering, technology, and applications. Computer is a resource that practitioners, researchers, and managers can rely on to provide timely information about current research developments, trends, best practices, and changes in the profession.
Design and analysis of algorithms, computer systems, and digital networks; methods for specifying, measuring, and modeling the performance of computers and computer systems; design of computer components, such as arithmetic units, data storage devices, and interface devices; design of reliable and testable digital devices and systems; computer networks and distributed computer systems; new computer organizations and architectures; applications of VLSI ...
Electrical insulation common to the design and construction of components and equipment for use in electric and electronic circuits and distribution systems at all frequencies.
The 26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2004
The aim of this study is to investigate the availability of supervised statistical clustering algorithm for image-based model analysis in positron emission tomography or nuclear medicine to form a functional image. Voxel-by- voxel model analysis can derive functional images, but bad statistic property in voxel-based PET data and huge number of voxels prevent to realize practical algorithm to form parametric ...
2007 IEEE Nuclear Science Symposium Conference Record, 2007
Positron annihilation spectroscopy provides a useful tool for the non- destructive study of subsurface microscopic defects. Variations in the electronic environment, from that of the bulk of the material, caused by defects introduce Coulombic forces which cause positrons to localize at the site of defects. This lifetime can vary from nanoseconds, if the positron forms a positronium atom before annihilation, ...
2009 1st International Conference on Advancements in Nuclear Instrumentation, Measurement Methods and their Applications, 2009
Carbon kinetics into the fruit is an agricultural issue on the growth and development of the organ to be harvested. Particularly, photoassimilate translocation and distribution are important topics for understanding the mechanism. In the present work, carbon-11 (<sup>11</sup>C) labeled photoassimilate translocation into fruits of tomato has been imaged using carbon-11-labeled carbon dioxide and the positron emission tomography (PET). Dynamice PET ...
2009 IEEE Nuclear Science Symposium Conference Record (NSS/MIC), 2009
Radionuclide-based imaging technologies have provided exciting new opportunities to life science researchers. However, success in the field of plant science is limited because most methods for studying plants are invasive and require statistical analysis and a large number of test plants. To clarify the mechanism of the growth and development of the agricultural produces to be harvested, we performed imaging ...
2007 IEEE/ICME International Conference on Complex Medical Engineering, 2007
When acquiring positron emission tomography (PET) brain scans dynamically from a patient, it would be helpful to be able to minimize confounding effects of his/her head movement. In this study, we attempted to coregister sequential frames in the dynamic fluorodeoxyglucose (FDG) PET image sequence, specifically addressing the challenge associated with the relatively low radiotracer uptake over the cortical areas in ...
The aim of this study is to investigate the availability of supervised statistical clustering algorithm for image-based model analysis in positron emission tomography or nuclear medicine to form a functional image. Voxel-by- voxel model analysis can derive functional images, but bad statistic property in voxel-based PET data and huge number of voxels prevent to realize practical algorithm to form parametric images. In this study, supervised clustering is applied to categorized PET data. The shape of tTAC is projected in multidimensional feature space, and noise propagation is modeled as multivariate Gaussian in the space. Simulation study shows that the estimates by the proposed algorithm was identical to the true values. And a clinical image of has physiologically acceptable aspect. We can conclude that supervised clustering sachem has potential to realize practical algorithm for voxel-based model analysis in PET.
Positron annihilation spectroscopy provides a useful tool for the non- destructive study of subsurface microscopic defects. Variations in the electronic environment, from that of the bulk of the material, caused by defects introduce Coulombic forces which cause positrons to localize at the site of defects. This lifetime can vary from nanoseconds, if the positron forms a positronium atom before annihilation, to picoseconds if it is involved in pick-off annihilation. By bunching the incident positron beam, the time- resolution of a measurement can greatly be enhanced, allowing the observation of the variation in the lifetime of positrons that undergo pick-off annihilation, which occurs in metals and semiconductors. This is achieved by narrowing the resolution function of the detection system, which allows the measurement of shorter lifetime components. This improved timing resolution, over other techniques, comes at the expense of more complex electronics but is capable of performing measurements over a wide range of timing resolutions. Simulations have been preformed to optimize the design of a bunched slow positron beam to be implemented at North Carolina State University. For the proposed apparatus, the DC beam produced by the positron source at the 1-MW PULSTAR reactor, located at NCSU, must first be chopped into small pulses. This is accomplished by applying a time-varying potential to a re-moderator in the beam line. This waveform accelerates positrons emitted from a transmission moderator, which the incident beam is focused upon, into bunches. This time- varying field has been calculated and is capable of accelerating positrons into pulses approximately 8.5 ns wide with a FWHM of 4 ns. Following this initial chopping stage, the positron pulses undergo further time focusing using applied rf fields to coaxial resonators. Current simulations demonstrate the capability of supplying a 2.4 ns (FWHM) pulse to the double harmonic buncher for final time focusing. The goal is to produce a pulsed positron beam with a time resolution of less than 100 ps capable of implanting positrons with kinetic energy up to 30 kV.
Carbon kinetics into the fruit is an agricultural issue on the growth and development of the organ to be harvested. Particularly, photoassimilate translocation and distribution are important topics for understanding the mechanism. In the present work, carbon-11 (<sup>11</sup>C) labeled photoassimilate translocation into fruits of tomato has been imaged using carbon-11-labeled carbon dioxide and the positron emission tomography (PET). Dynamice PET data of gradual increasing of <sup>11</sup>C activity and its distribution is acquired quantitatively in intact plant body. This indicates that the three dimensional photoassimilate translocation into the fruits is imaged successfully and carbon kinetics is analyzed to understand the plant physiology and nutrition.
Radionuclide-based imaging technologies have provided exciting new opportunities to life science researchers. However, success in the field of plant science is limited because most methods for studying plants are invasive and require statistical analysis and a large number of test plants. To clarify the mechanism of the growth and development of the agricultural produces to be harvested, we performed imaging experiments of sugar translocation to the sink organ of fruit. A leaf near the target fruits (eggplant and tomato) was exposed to carbon-11-labeled carbon dioxide, and the translocations of carbon-11-labeled photoassimilate into fruits were assessed by images obtained using the positron-emitting tracer imaging system and small animal positron emission tomography system. Serial images thus obtained showed gradually increasing <sup>11</sup>C activity and its nonuniform distribution in the fruit. These experimental methods will be useful in not only investigating plant physiology, such as mechanisms underlying fruit growth, but also solving certain environmental and food problems.
When acquiring positron emission tomography (PET) brain scans dynamically from a patient, it would be helpful to be able to minimize confounding effects of his/her head movement. In this study, we attempted to coregister sequential frames in the dynamic fluorodeoxyglucose (FDG) PET image sequence, specifically addressing the challenge associated with the relatively low radiotracer uptake over the cortical areas in the early short frames. PET data were acquired dynamically over sixty minutes in three healthy volunteers (frame durations ranged from 2 seconds to 5 minutes). We realigned each of the early short frames to its immediate predecessor using normalized mutual information (NMI). Afterward, the same procedure was repeated to realign the summation of the early frames, as well as each of the later frames with durations of 5 minutes and sufficient cortical tracer uptake. To validate our proposed procedure, we artificially moved frames using known linear rotations and translocations and compared the 6 NMI estimated rigid-body transformation parameters to the actual misalignment parameters and compared image-derived carotid artery FDG input function in the realigned and original images. While counting statistics in the first 3 frames (22 seconds after FDG administration) precluded us from accurately addressing misalignments, the NMI reliably recovered translocations as great as 7 mm and rotations as great as 8 degrees for all other frames. Moreover, misalignment errors in the constructed input function from the carotid artery region were able to be corrected. Our NMI-based strategy for the realignment of sequential frames appears to provide a helpful way to determine the severity of the head movement during a PET scan and correct for the effects. Additional studies are needed to address additional confounds associated with the misalignment between transmission and emission scans.
Self-organization of electron-positron substance is considered in the problems of gamma-electronics (γ electronics), in which investigates the interaction between the electron and positron flows with electromagnetic fields in γ-wavelength range. In devices of gamma-electronics and microwave electronics important role play collective processes that allow organizing an optimal grouping of charged particles and efficient braking clots.
Positron Range Visualization Using the Analytical and Iterative Image Reconstruction Methods From a Preclinical PET Scanner With LYSO Scintillators Coupled to SiPM Detectors: Comparison With Simulated Results
An evaluation of the image quality of the preclinical positron emission tomography scanner consisting of the SensL's SMT C-series silicon photomultiplier (SiPM) arrays coupled with double jaw layer lutetium-yttrium oxyorthosilicate (LYSO) crystals was achieved. The simulated data of a Jaszczak phantom filled with Na-22 and O-15 were compared with reconstructed data of the same phantom when it was filled with Na-22. Two different reconstruction methods were applied in order to visualize any positron range effects that occur within the phantom. The filtered back-projection (FBP) and ordered-subset expectation maximization (OSEM) algorithms provided useful information regarding the spatial resolution of the scanner, showing that these sensors can visually correct the structure of the phantom. The OSEM method appeared to be more reliable than FBP, even when a Compton correction was applied on the data.
Crystal identification (CI) of phoswich detectors is a technique used in positron emission tomography (PET) for improving spatial resolution through depth-of-interaction determination or higher pixelization. Digital algorithms using advanced digital signal processing techniques currently provide the most powerful approaches for CI of phoswich detectors made of crystals with only slightly different scintillation decay times. Such methods can be implemented in the all-digital architecture of LabPET, a small animal PET scanner developed in Sherbrooke, for fast and accurate real-time CI. In order to validate the new CI algorithms and assess their performance for different front-end electronics, a pulse generator simulator was developed to generate PET signals and investigate the effects of factors such as electronic noise, photon statistics and pulse shaping filter. The pulse generator was validated with LabPET-like pulses and CI results were compared with experimental data. The pulse simulator enables CI algorithms to be validated together with detector performance such as energy and timing resolution at an early stage of scanner design.
Small animal Positron Emission Tomography (PET) should provide accurate quantification of regional radiotracer concentrations and high spatial resolution. This is challenging for non-pure positron emitters with high positron endpoint energies, such as I-124: On the one hand the cascade gammas emitted from this isotope can produce coincidence events with the 511 keV annihilation photons leading to quantification errors. On the other hand the long range of the high energy positron degrades spatial resolution. This paper presents the implementation of a comprehensive correction technique for both of these effects. The established corrections include a modified sinogram- based tail-fitting approach to correct for scatter, random and cascade gamma coincidences and a compensation for resolution degradation effects during the image reconstruction. Resolution losses were compensated for by an iterative algorithm which incorporates a convolution kernel derived from line source measurements for the microPET Focus 120 system. The entire processing chain for these corrections was implemented, whereas previous work has only addressed parts of this process. Monte Carlo simulations with GATE and measurements of mice with the microPET Focus 120 show that the proposed method reduces absolute quantification errors on average to 2.6% compared to 15.6% for the ordinary Maximum Likelihood Expectation Maximization algorithm. Furthermore resolution was improved in the order of 11-29% depending on the number of convolution iterations. In summary, a comprehensive, fast and robust algorithm for the correction of small animal PET studies with I-124 was developed which improves quantitative accuracy and spatial resolution.
Summary form only given, as follows. As is known, wide application in physics and chemistry of a positron and positronium atom (Ps) has received a spur model formation of Ps atom. In the present work the new plasma submissions about positron spur, originating during passing of positrons through substance are offered. The evaluations of such characteristic parameters of positron spur, as it life-time and sizes are obtained. The kinetics of elementary processes in volume of spur is discussed also.
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