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A globally adaptive image compression structure is introduced for use in a tactical RPV environment. The structure described would provide an operator with the flexibility to dynamically maximize the usefulness of a limited and changing data rate. The concepts would potentially simplify system design while at the same time improving overall system performance.
Genomic instability plays a significant role in lung cancer. Although substantial research has been conducted using both clinical and theoretical studies, it is still a hotly debated issue to whether genomic instability is necessary or whether genomic instability precedes oncogenes activation and tumor suppressor genes inactivation for lung cancer. In response to this issue, we come up with a mathematical model incorporating effects of genomic instability to investigate the genomic instability pathway of human lung cancer. The presented model are applied to match the incidence rate data of lung cancer from the Life Span Study cohort of the atomic bomb survivors in Nagasaki and Hiroshima and the Surveillance Epidemiology and End Results registry in the United States. Model results suggest that genomic instability is necessary in the tumorigenesis of lung cancer, and genomic instability has no significant impact on the net proliferation rate of cells by statistical criteria. By comparing the results of the LSS data to those of the SEER data, we conclude that the genomic instability pathway exhibits a sensitivity to radiation exposure, more intensive in male patients.
A test of lepton flavor universality in B ± → K ± μ + μ – and B ± → K ± e + e – decays, as well as a measurement of differential and integrated branching fractions of a nonresonant B ± → K ± μ + μ – decay are presented. The analysis is made possible by a dedicated data set of proton-proton collisions at $\sqrt{s}$ = 13 TeV recorded in 2018, by the CMS experiment at the LHC, using a special high-rate data stream designed for collecting about 10 billion unbiased b hadron decays. The ratio of the branching fractions B(B ± → K ± μ + μ – ) to B(B ± → K ± e + e – ) is determined from the measured double ratio R(K) of these decays to the respective branching fractions of the B ± → J/ψK ± with J/ψ → μ + μ – and e + e – decays, which allow for significant cancellation of systematic uncertainties. The ratio R(K) is measured in the range 1.1 < q 2 < 6.0 GeV 2 , where q is the invariant mass of the lepton pair, and is found to be R(K) = 0.78$^{+0.47}_{-0.23}$, in agreement with the standard model expectation R(K) ≈ 1. This measurement is limited by the statistical precision of the electron channel. The integrated branching fraction in the same q 2 range, B(B ± → K ± μ + μ – ) = (12.42 ± 0.68) x 10 -8 , is consistent with the present world-average value and has a comparable precision.
Supervised and unsupervised classification modes are discussed in light of the multidisciplinary, high data rate requirements of the ERTS satellites soon to be launched. Inadequacies of each system in light of these requirements are noted and a compromise solution to the data classification system is proposed. An example of results obtained with an implementation of this system are shown and compared with results from a supervised classification scheme.
Supervised and unsupervised classification modes are discussed in light of the multidisciplinary, high data rate requirements of the ERTS satellites soon to be launched. Inadequacies of each system in light of these requirements are noted and a compromise solution to the data classification system is proposed. An example of results obtained with an implementation of this system are shown and compared with results from a supervised classification scheme.
In this research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing, a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RM subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a high data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study, which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating, and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these sub-trellises.
In this research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RM subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a high data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these subtrellises.
In his research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RNI subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second (Mbps). The combination of a large number of states and a hi ch data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high-speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these sub-trellises.
In his research, we have proposed the (64, 40, 8) subcode of the third-order Reed-Muller (RM) code to NASA for high-speed satellite communications. This RM subcode can be used either alone or as an inner code of a concatenated coding system with the NASA standard (255, 233, 33) Reed-Solomon (RS) code as the outer code to achieve high performance (or low bit-error rate) with reduced decoding complexity. It can also be used as a component code in a multilevel bandwidth efficient coded modulation system to achieve reliable bandwidth efficient data transmission. This report will summarize the key progress we have made toward achieving our eventual goal of implementing a decoder system based upon this code. In the first phase of study, we investigated the complexities of various sectionalized trellis diagrams for the proposed (64, 40, 8) RM subcode. We found a specific 8-trellis diagram for this code which requires the least decoding complexity with a high possibility of achieving a decoding speed of 600 M bits per second(Mbps). The combination of a large number of states and a high data rate will be made possible due to the utilization of a high degree of parallelism throughout the architecture. This trellis diagram will be presented and briefly described. In the second phase of study which was carried out through the past year, we investigated circuit architectures to determine the feasibility of VLSI implementation of a high- speed Viterbi decoder based on this 8-section trellis diagram. We began to examine specific design and implementation approaches to implement a fully custom integrated circuit (IC) which will be a key building block for a decoder system implementation. The key results will be presented in this report. This report will be divided into three primary sections. First, we will briefly describe the system block diagram in which the proposed decoder is assumed to be operating and present some of the key architectural approaches being used to implement the system at high speed. Second, we will describe details of the 8-trellis diagram we found to best meet the trade-offs between chip and overall system complexity. The chosen approach implements the trellis for the (64, 40, 8) RM subcode with 32 independent sub-trellises. And third, we will describe results of our feasibility study on the implementation of such an IC chip in CMOS technology to implement one of these subtrellises.
This paper reviews the capabilities of a plasticity-induced crack-closure model to predict fatigue lives of metallic materials using 'small-crack theory' for various materials and loading conditions. Crack-tip constraint factors, to account for three-dimensional state-of-stress effects, were selected to correlate large-crack growth rate data as a function of the effective-stress-intensity factor range (delta K(eff)) under constant-amplitude loading. Some modifications to the delta k(eff)-rate relations were needed in the near-threshold regime to fit measured small-crack growth rate behavior and fatigue endurance limits. The model was then used to calculate small- and large-crack growth rates, and to predict total fatigue lives, for notched and un-notched specimens made of two aluminum alloys and a steel under constant-amplitude and spectrum loading. Fatigue lives were calculated using the crack-growth relations and microstructural features like those that initiated cracks for the aluminum alloys and steel for edge-notched specimens. An equivalent-initial-flaw-size concept was used to calculate fatigue lives in other cases. Results from the tests and analyses agreed well.
The U.S. is beginning an $800-million project to create an information technology infrastructure at Mars. This will be essentially a Martian internet where robotic spacecraft will conduct high-data-rate exchanges between themselves and with their Earth-based teams. The objective is to better control increasingly ambitious robotic missions and to return more imagery and data from those flights for faster distribution to the science community and public. The focal point will be the Mars Telecommunication Orbiter (MTO), a Mars orbiting communications satellite already approved and funded by Congress for launch to the red planet in 2009.MTO's advanced operational microwave capability should be able to relay to Earth magnitudes more information than current spacecraft, as well as near real-time images from Nasa's next generation of rovers, also set for launch in 2009.
The Design and Validation of High Date Rate Ka- Band Software Defined Radio for Small Satellite project will develop a novel Ka-band software defined radio (SDR) that is capable of establishing high data rate inter-satellite links with a throughput of 500 megabits per second (Mb/s) and providing millimeter ranging precision. The system will be designed to operate with high performance and reliability that is robust against various interference effects and network anomalies. The Ka-band radio resulting from this work will improve upon state of the art Ka-band radios in terms of dimensional size, mass and power dissipation, which limit their use in small satellites.
Bidirectional, high data rate, low size, weight, and power (SWaP), and low cost free space optical links are needed for space communication applications to send and receive large volumes of data. We are exploring design strategies for optical transceivers to reduce SWaP and cost through increased misalignment tolerance (pointing requirement reduction) and sharing the optical transmit and receive paths (imposing optical symmetry). In applications where the detector is fiber coupled, the fiber numerical aperture is the main driver of the pointing accuracy requirement. Unfortunately, reducing the pointing requirement by increasing the fiber numerical aperture symmetrically causes instability in received power over small environmental changes. This paper explores double clad fibers as a solution to both reduce the power instability and increase the pointing accuracy tolerance. Double clad fibers can transmit a Gaussian beam from a single mode fiber and receive in a multi-mode aperture. Results show that double clad fiber have an improved misalignment tolerance and a higher stability for small changes in temperature when compared to single mode fibers and multimode fibers. Also, double clad fibers are shown to match the performance of an asymmetrical link design with a single mode transmit fiber and a multimode receive fiber.
Bidirectional, high data rate, low size, weight, and power (SWaP), and low cost free space optical links are needed for space communication applications to send and receive large volumes of data. We are exploring design strategies for optical transceivers to reduce SWaP and cost through increased misalignment tolerance (pointing requirement reduction) and sharing the optical transmit and receive paths (imposing optical symmetry). In applications where the detector is fiber coupled, the fiber numerical aperture is the main driver of the pointing accuracy requirement. Unfortunately, reducing the pointing requirement by increasing the fiber numerical aperture symmetrically causes instability in received power over small environmental changes. This paper explores double clad fibers as a solution to both reduce the power instability and increase the pointing accuracy tolerance. Double clad fibers can transmit a Gaussian beam from a single mode fiber and receive in a multi-mode aperture. Results show that double clad fiber have an improved misalignment tolerance and a higher stability for small changes in temperature when compared to single mode fibers and multimode fibers. Also, double clad fibers are shown to match the performance of an asymmetrical link design with a single mode transmit fiber and a multimode receive fiber.
The dependence of laser velocimeter measurement rate on flow velocity is discussed. Investigations outlining that any dependence is purely statistical, and is nonstationary both spatially and temporally, are described. Main conclusions drawn are that the times between successive particle arrivals should be routinely measured and the calculation of the velocity data rate correlation coefficient should be performed to determine if a dependency exists. If none is found, accept the data ensemble as an independent sample of the flow. If a dependency is found, the data should be modified to obtain an independent sample. Universal correcting procedures should never be applied because their underlying assumptions are not valid.
There is a strong rationale for increasing the rate of information return from imaging class experiments aboard both terrestrial and planetary spacecraft. Future imaging systems will be designed with increased spatial resolution, broader spectral range and more spectral channels (or higher spectral resolution). The data rate implied by these improved performance characteristics can be expected to grow more rapidly than the projected telecommunications capability. One solution to this dilemma is the use of improved onboard data processing. The use of onboard classification processing in a multispectral imager can result in orders of magnitude increase in information transfer for very specific types of imaging tasks. Several of these processing functions are included in the conceptual design of an Infrared Multispectral Imager which would map the spatial distribution of characteristic geologic features associated with deposits of economic minerals.
A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN 3636, “Technical Program Plan for INL Advanced Reactor Technologies Technology Development Office/Advanced Gas Reactor Fuel Development and Qualification Program”). The AGR 3/4 test was inserted in the Northeast Flux Trap position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in December 2011 and successfully completed irradiation in mid-April 2014, resulting in irradiation of the tristructural isotropic (TRISO) fuel for 369.1 effective full-power days (EFPDs) during approximately 2.4 calendar years. The AGR 3/4 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as run thermal analysis has been performed separately on each of twelve AGR 3/4 capsules for the entire irradiation as discussed in ECAR-2807, “AGR 3/4 Daily As Run Thermal Analyses”. The ABAQUS code’s finite element-based thermal model predicts the daily average volume average (VA) fuel temperature (FT), peak FT, and graphite matrix, sleeve, and sink temperature in each capsule. The JMOCUP simulation codes were also created to perform depletion calculations for the AGR 3/4 experiment (ECAR-2753, “JMOCUP As-Run Daily Physics Depletion Calculation for the AGR 3/4 TRISO Particle Experiment in ATR Northeast Flux Trap”). This depletion analysis provides fast fluence and fission heat rate data for all components (fuel compacts, graphite rings, stainless steel retainer, etc.), which are used as inputs for the thermal analysis codes. The graphite temperatures from thermocouples (TCs) in each capsule were used to calibrate these thermal analysis codes. However, given the high rate of TC failure under the harsh irradiation and thermal conditions in the AGR capsules, the thermal analysis results are very useful in aiding TC data qualification, increasing the confidence in delineating failures of the measuring instruments (TCs) from physical mechanisms that may have shifted the system thermal response.
The dependence on supersaturation of the growth rate of single crystals of the protein canavalin is studied. In the supersaturation ranges studied, the rate-limiting step for growth is best described by a screw dislocation mechanism associated with interface attachment kinetics. Using a ln-ln plot, the growth-rate data is found to fit a predictive relationship of the form G = 0.012 x the supersaturation to the 6.66, which, together with the solubility curves, allows the growth rate to be estimated under a variety of conditions.