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AniMAIRE (Anisotropic Model for Atmospheric Ionising Radiation Effects) is a new model and Python toolkit for calculating radiation dose rates experienced by aircraft during anisotropic solar energetic particle events. AniMAIRE expands the physics of the MAIRE + model such that dose rate calculations can be performed for anisotropic solar energetic particle conditions by supplying a proton or alpha particle rigidity spectrum, a pitch angle distribution, and the conditions of Earth's magnetosphere. In this paper, we describe the algorithm and top‐level structure of AniMAIRE and showcase AniMAIRE's capabilities by analyzing the dose rate maps that AniMAIRE produces when the time‐dependent spectra and pitch angle distribution for Ground Level Enhancement (GLE) 71 are input. We find that the dose rates AniMAIRE produces for the event fall between the dose rates produced by the WASAVIES and CRAC:DOMO models. Dose rate maps that evolve throughout the event are also shown, and it is found that each peak in the input pitch angle distribution generates a dose rate hotspot in each of the polar regions. AniMAIRE has been made available openly online so that it can be downloaded and run freely on local machines and so that the space weather community can easily contribute to it using Github forking. Plain Language Summary: Solar particle events occur when particles are accelerated in eruptions on the Sun. If these particles hit Earth and have enough energy, they can penetrate Earth's magnetosphere and atmosphere, creating radiation showers that increase the radiation in Earth's atmosphere. When such increases are detected by neutron monitors at sea level, they are known as Ground‐Level Enhancements (GLEs), which occur once a year on average. GLEs can cause issues in aircraft electronics and cause passengers and crew on airplanes to experience heightened radiation doses. In this paper, we describe a new model to calculate radiation dose rates in the atmosphere during GLEs, called AniMAIRE. Most models that exist to date are only able to calculate radiation dose rates when all particles are hitting Earth equally from all directions, however this approximation is only reliable during the later stages of events, and isn't accurate for many GLEs. AniMAIRE has been designed so it doesn't need to rely on this approximation, and can calculate dose rates for situations where it is supplied a direction‐dependent particle flux, as well as those independent of direction. AniMAIRE has been tested across a GLE in May 2012, showing the direction dependent approach is necessary. Key Points: AniMAIRE can simulate atmospheric radiation and electronics effects from anyinput anisotropic distribution of particles hitting EarthAnisotropy is important in the event‐integrated dose calculation for GLE71 according to AniMAIREAniMAIRE has been made openly available online, such that anyone can run and experiment with it, or contribute to the model through forking [ABSTRACT FROM AUTHOR]

The effect of single event transient (SET) on 6T SRAM cell employing a 20 nm silicon‐based junctionless tunneling field effect transistor (JLTFET) is explored for the first time. JLTFET‐based SRAM circuit is designed using the look up table‐based Verilog A code obtained from TCAD values of the device. After verifying SRAM circuit for its functionality, the stability parameters, read static noise margin (RSNM), write static noise margin (WSNM), read/write delay, and power consumption are evaluated. It is observed that the circuit has a good stability of noise margin and lesser delay. The radiation study is carried out using a transient current source striking at one of the output nodes. This causes single event upset (SEU) which changes the data stored in the memory cell giving rise to soft error (SER). SER is recovered by the radiation hardening by design (RHBD) technique with an additional RC network between two cross coupled inverters. The performance metrics, read/write delay, and the power consumption before, during, and after the radiation strike are analyzed. It is observed that SER gets totally eliminated with less recovery time at the expense of a slight increase in power and delay. [ABSTRACT FROM AUTHOR]

With continuous downscaling of transistor sizes, the sensitivity to single event effect (SET) has become one of the most important reliability issues for aerospace integrated circuits. Besides the SET, integrated circuits will be affected by multiphysics such as temperature and voltage when working in space. Currently, the commonly used modeling methods are based on physical mechanisms and the double exponential pulse current. However, both methods are hard to build an accurate SET current model when various variables are considered. In this article, a novel machine learning modeling method of multiphysics SET is proposed, using intelligent algorithms to optimize the network also. With this method, we can obtain a reasonable and accurate multiphysics SET model based on neural network with single hidden layer, and there is no need to consider complex physical mechanisms. The model data is collected from TCAD simulation. Ant colony algorithm was used to optimize the initial values of the network. The RMS (root mean square error) of modeling result is less than 2%. [ABSTRACT FROM AUTHOR]

Background: Indoor dust (ID) is a source of peanut proteins and immunostimulatory adjuvants (e.g. LPS) that can promote airway sensitization to peanut. We aimed to determine whether a single airway exposure to peanut plus adjuvant is sufficient to prevent oral tolerance. Methods: To determine the effect of a single priming event, C57BL/6J mice were exposed once to peanut plus adjuvant through the airway, followed by either airway or low‐dose oral exposure to peanut, and assessed for peanut allergy. Oral tolerance was investigated by feeding high‐dose peanut followed by airway sensitization. To determine whether a single priming could prevent oral tolerance, the high‐dose peanut regimen was applied after a single airway exposure to peanut plus adjuvant. Peanut‐specific IgE and IgG1 were quantified, and mice were challenged to peanut to assess allergy. Peanut‐specific CD4+ memory T cells (CD4+TCRβ+CD44hiCD154+) were quantified in mediastinal lymph nodes following airway priming. Results: Mice co‐exposed to peanut with LPS or ID through the airway were primed to develop peanut allergy after subsequent low‐dose oral or airway exposures to peanut. Oral tolerance was induced in mice fed high‐dose peanut prior to airway sensitization. In contrast, mice fed high‐dose peanut following a single airway exposure to peanut plus adjuvant led to allergy. Peanut‐specific CD4+ memory T cells were detected as early as 7 days after the single airway priming with peanut plus adjuvant, however, delaying peanut feeding even 1 day following priming led to allergy, whereas peanut feeding the same day as priming led to tolerance. Conclusions: A single airway exposure to peanut plus adjuvant is sufficient to prime the immune system to develop allergy following subsequent high‐dose oral exposure. These results highlight the importance of introducing peanut as early as possible to prevent sensitization through a non‐oral priming event. [ABSTRACT FROM AUTHOR]

Most of the traditional studies based on single event effects (SEEs) favor the analysis of electrical mechanisms of semiconductor devices. Professional simulation software in microelectronics requires researchers to have a solid knowledge of microelectronics theory, and the modeling threshold of the software is relatively high, the simulation speed is slow, and accurate simulation of inter‐particle and particle–material interactions is lacking. SEEs are related to linear energy transfer (LET), in this paper, a method is proposed to obtain LET datas to predict SEEs of particles incident on silicon materials by using the Geant4 Monte Carlo toolkit in combination with a dense convolutional network to accurately and rapidly estimate the energy deposition characteristics of the particles. The proposed network structure has a high prediction accuracy with a mean square error （MSE） of only 1.77 × 10−4. Compared with Geant4, which takes 1 min to compute a set of data, the proposed network structure takes only 0.0817 s. The method explores the feasibility of using Geant4 to model semiconductor devices combined with deep learning algorithms, providing a new research perspective for the prediction of microelectronic devices and making it possible to explore the influence of integrated circuits by SEEs. [ABSTRACT FROM AUTHOR]

During periods of no or low crop growth in dryland cropping systems, tillage can reduce residue coverage and thereby elevate wind erosion risk. We measured wind erosion on a silt loam, Haplustoll soil in North Dakota (456 mm precipitation yr–1) in response to levels of tillage applied once in spring during fallow following a small grain–sunflower (Helianthus annuus L.) rotation. Treatments were no‐tillage (NT), one‐pass tandem disk tillage (TDT), and two‐pass offset disk tillage (ODT). Erosion flux was measured with sediment samplers near peripheries of >1‐ha replicated plots from May through September 2003 and 2004. Soil losses in ODT, TDT, and NT were 12.0, 4.8, and 2.1 Mg ha–1, respectively, in 2003 and 2.6, 1.6, and 1.4 Mg ha–1 in 2004. The greatest loss, 12.0 Mg ha–1, was equivalent to 1‐mm soil depth. The two‐ to fivefold greater erosion in 2003, a year with 2 mo of <30% of average precipitation, appears linked to a decline in residue coverage. Coverage remained about the same in NT and increased in tilled treatments during 2004 with more average precipitation. Our measurements of wind erosion have shown how the residue‐destroying effects of a single tillage event can be considerably exacerbated by a moderate, seasonal drought. This indicates the critical importance of NT for limiting soil and residue disturbance and reducing wind erosion risk from drought‐affected plant growth failure in semiarid cropping systems. Core Ideas: Wind erosion loss was two‐ to sixfold greater under disk tillage than no‐tillage.Seasonal drought led to less weed growth and residue coverage.Seasonal drought resulted in two‐ to fivefold greater wind erosion loss.The Revised Wind Erosion Equation (RWEQ) model indicated that residue coverage conferred the greatest resistance to erosion. [ABSTRACT FROM AUTHOR]

Significant increases to the atmospheric radiation environment are recorded by a network of ground level neutron monitors as ground level enhancements (GLEs). These space weather phenomena pose a risk to aviation via single event effects in aircraft electronics and ionizing dose to passengers and crew. Under the UK Space Weather Instrumentation, Measurement, Modeling and Risk programme, we have developed a new model to provide nowcasts of the aviation radiation environment, including both the galactic cosmic ray (GCR) background and during GLE events. The Model for Atmospheric Ionising Radiation Effects (MAIRE+) uses multiple data sources to characterize primary GCR and GLE particle spectra and combines these with precalculated geomagnetic and atmospheric response matrices to predict particle fluxes from ground level to 20 km altitude across the entire globe. Two European neutron monitors (located at Oulu in Finland and Dourbes in Belgium) are used as the primary indicators of GLE intensity in order to maximize accuracy over UK airspace. Outputs from MAIRE+ for the historical GLEs in September and October 1989 are compared to recalibrated empirical data from a solid‐state detector that was carried on Concorde in that period. The model will be hosted in the UK and will provide additional capability to the Met Office Space Weather Operations Center (MOSWOC). Plain Language Summary: Ionizing radiation in the atmosphere is primarily caused by galactic cosmic rays (GCR) interacting with the upper atmosphere, creating showers of secondary radiation. At aviation altitudes the radiation environment is hundreds of times more intense than that experienced at the ground level. This relatively stable background level of radiation is punctuated by space weather events called ground level enhancements (GLEs), when energetic solar protons arrive at Earth and lead to elevated atmospheric radiation levels that can be orders of magnitude greater than background levels. Under the UK Space Weather Instrumentation, Measurement, Modeling and Risk programme, we have developed a new model to provide nowcasts of the aviation radiation environment, including both the GCR background and during GLE events. Through our Model for Atmospheric Ionising Radiation Effects, we show how data from ground level neutron monitors can be used to characterize the atmospheric radiation environment from ground level to 20 km altitude across the entire globe. Key Points: The new Model for Atmospheric Ionising Radiation Effects (MAIRE+) is presentedMAIRE+ uses neutron monitor data, sunspot number, Kp, and geostationary proton flux to nowcast the aviation radiation environmentModel outputs are compared to data from a solid‐state detector carried on board Concorde during ground level enhancements in 1989 [ABSTRACT FROM AUTHOR]

The Nowcast of Aerospace Ionizing RAdiation System (NAIRAS) version 3 model is available to the community through the Community Coordinated Modeling Center run‐on‐request (RoR) service. The RoR capability allows the user to run the NAIRAS model for customized applications and time‐periods using two run options. The global dosimetric run option mirrors the execution of the real‐time NAIRAS run mode. This class of run option capability provides global context and situational awareness of the atmospheric ionizing radiation environment. The flight trajectory run option allows the user to upload an aircraft, balloon, or spaceflight trajectory file. This class of run option allows detailed human radiation flight exposure characterization, detailed comparisons to onboard dosimeters, and the assessment of single event effects (SEE) in aircraft and spacecraft electronic systems. The model output includes dosimetric quantities, differential and integral flux, and fluence quantities. The flux and fluence quantities are a new feature in version 3 for the assessment of SEE. The trajectory run option and the extension of the model domain to the space environment is also a new feature in version 3. Plain Language Summary: The Nowcast of Aerospace Ionizing RAdiation System version 3 model is available to the community through the Community Coordinated Modeling Center run‐on‐request (RoR) service. The RoR capability provides a scientific and engineering analysis tool to characterize the atmospheric and space ionizing radiation environments for the assessment of human radiation exposure and radiation effects to aircraft and spacecraft electronic systems. Key Points: Nowcast of Aerospace Ionizing RAdiation System (NAIRAS) version 3 run‐on‐request service is available to the community through CCMCNAIRAS version 3 includes an extension of the model domain from the atmosphere to the space environmentNAIRAS version 3 includes differential and integral flux for assessing SEE in aircraft and spacecraft electronic systems [ABSTRACT FROM AUTHOR]

Understanding species' responses to upwelling may be especially important in light of ongoing environmental change. Upwelling frequency and intensity are expected to increase in the future, while ocean acidification and deoxygenation are expected to decrease the pH and dissolved oxygen (DO) of upwelled waters. However, the acute effects of a single upwelling event and the integrated effects of multiple upwelling events on marine organisms are poorly understood. Here, we use in situ measurements of pH, temperature, and DO to characterize the covariance of environmental conditions within upwelling‐dominated kelp forest ecosystems. We then test the effects of acute (0–3 days) and chronic (1–3 months) upwelling on the performance of two species of kelp forest grazers, the echinoderm, Mesocentrotus franciscanus, and the gastropod, Promartynia pulligo. We exposed organisms to static conditions in a regression design to determine the shape of the relationship between upwelling and performance and provide insights into the potential effects in a variable environment. We found that respiration, grazing, growth, and net calcification decline linearly with increasing upwelling intensity for M. francicanus over both acute and chronic timescales. Promartynia pulligo exhibited decreased respiration, grazing, and net calcification with increased upwelling intensity after chronic exposure, but we did not detect an effect over acute timescales or on growth after chronic exposure. Given the highly correlated nature of pH, temperature, and DO in the California Current, our results suggest the relationship between upwelling intensity and growth in the 3‐month trial could potentially be used to estimate growth integrated over long‐term dynamic oceanographic conditions for M. franciscanus. Together, these results indicate current exposure to upwelling may reduce species performance and predicted future increases in upwelling frequency and intensity could affect ecosystem function by modifying the ecological roles of key species. [ABSTRACT FROM AUTHOR]

Although they have better electrical and thermal properties, thermal issues have become an important challenge to design modern integrated circuits with single‐walled carbon nanotube (SWCNT) bundle interconnects. The equivalent RLC model for SWCNT bundle interconnect is analyzed. Based on the proposed circuit for single event crosstalk (SEC), the influences of the length of line, nanotube diameter, metallic nanotube ratio, and technology node on SEC at different temperatures are studied. The potential impact mechanisms are also discussed. The simulation results show that, compared with one in copper line, peak voltage and pulse width of SEC in SWCNT interconnect are reduced by an average of 23.7% and 8.8%, respectively. The larger the diameter of SWCNT is or the more the ratio of metallic SWCNT is, the weaker the effect of SEC will be. With the increase of the length of line, the crosstalk effect will increase. The pulse width of SEC is more sensitive to the temperature when the length of line is longer. However, the peak voltage is more sensitive to the temperature when the length of line is shorter. As the technology node shrinks from 21 nm to 9.5 nm, the noise area of SEC increases from 0.55 V•ns to 1.89 V•ns, which results in that the crosstalk action time increases significantly. [ABSTRACT FROM AUTHOR]

Conventional flip‐flops are more vulnerable to particle strikes in a radiation environment. To overcome this disadvantage, in the literature, many radiation‐hardened flip‐flops (FFs) based on techniques like triple modular redundancy, dual interlocked cell, Quatro and guard‐gated Quatro cell, and so on, are discussed. The flip‐flop realized using radiation hardened by design Quatro cell is named as the improved version of Quatro flip‐flop (IVQFF). Single event upset (SEU) at inverter stages of master/slave and at output are the two drawbacks of IVQFF. This study proposes a guard‐gated Quatro FF (GQFF) using guard‐gated Quatro cell and Muller C‐element. To overcome the SEU at inverter stages of IVQFF, in GQFF, the inverter stages are realized in a parallel fashion. A dual‐input Muller C‐element is connected to the GQFF output stage to mask the SEU and thus maintain the correct output. The proposed GQFF tolerates both single node upset (SNU) and double node upset (DNU). It also achieves low power. To prove the efficacy, GQFF and the existing FFs are implemented in 45 nm Complementary Metal Oxide Semiconductor (CMOS) technology. From the simulation results, it may be noted that the GQFF is 100% immune to SNUs and 50% immune to DNUs. [ABSTRACT FROM AUTHOR]

The single event burnout (SEB) effects of SiC power MOSFET are investigated by irradiations. An SEB is observed when drain biased above 400 V for 181Ta ion irradiation. The failure analysis shows a melting "hole" near the gate region due to the thermal runaway. Based on TCAD simulations, the impact ionization and parasitic bipolar are the key factors to trigger SEB in SiC MOSFET. Unlike the impact ionization, the turning on of the parasitic bipolar is not necessary for an SEB. But it will significantly reduce the threshold of SEB. Except for SEB, another permanent damage mode is also observed, which is manifested as the increase of leakage current and the abnormal of the output characteristics. This damage may be related to the latent track produced by heavy ion according to the failure analysis. The SEBs are observed for proton irradiations. The maximum LET value of the proton‐induced secondary ions can reach 13.9 MeV cm2/mg for 100 MeV proton. The simulations imply that most of the secondary ions can contribute to SEB. The biggest discrepancy from heavy ion irradiation is that no leakage current increases and output characteristics degradations are observed for the device without SEB after proton irradiation. [ABSTRACT FROM AUTHOR]

Altering the performance of single transistors and integrated circuits at nominal operating conditions over time, as well as soft errors, are serious reliability issues for integrated CMOS circuits, especially when used in space applications. In principle, the effect of soft errors becomes even more critical if the circuit performance degrades over time. To address this detrimental behavior, the impact of performance degradation due to NBTI on the soft error susceptibility of integrated circuits is analyzed thoroughly. For this, we analyze the critical charge sensitivity of the two‐input NAND gate and NOR gate for different operating temperatures at stress times up to 3 years. The results show that the critical charge decreases with the temperature and strongly depends on the input states. Next, we validate the results employing the c17 ISCAS'85 benchmark suite, employing the PTM model with the HSPICE to estimate the soft error at the sensitive nodes. The critical charge is observed to be sensitive to the selected supply voltage and device temperature and thus provides a good measure for the soft error susceptibility with respect to NBTI at various operation conditions. [ABSTRACT FROM AUTHOR]

Compressed ultrafast photography (CUP) is an emerging potent technique that allows imaging a nonrepeatable or difficult‐to‐produce transient event in a single shot. Despite many recent advances, existing CUP techniques operate only at visible and near‐infrared wavelengths. In addition, spatial encoding via a digital micromirror device (DMD) in CUP systems often limits its field of view and imaging speeds. Finally, conventional reconstruction algorithms have limited control of the reconstruction process to further improve the image quality in the recovered (x,y,t) datacubes of the scene. To overcome these limitations, this article reports a single‐shot UV‐CUP that exhibits a sequence depth of up to 1500 frames with a size of 1750 × 500 (x,y) pixels at an imaging speed of 0.5 trillion frames per second. A patterned photocathode is integrated into a streak camera, which overcomes the previous restrictions in DMD‐based spatial encoding and improves the system's compactness. Meanwhile, the plug‐and‐play alternating direction method of multipliers algorithm is implemented to CUP's image reconstruction to enhance reconstructed image quality. UV‐CUP's single‐shot ultrafast imaging ability is demonstrated by recording UV pulses transmitting through various spatial patterns. UV‐CUP is expected to find many applications in both fundamental and applied science. [ABSTRACT FROM AUTHOR]

The use of optical imaging and bipolar electrochemical arrays is a powerful approach for optically monitoring as well as spatially and temporally resolving heterogeneous electron-transfer processes. Previous studies, however, have been largely limited to the study of slower or steady-state redox processes. In this work, we use electrochemiluminescence (ECL) to demonstrate the ability to optically record transient collision events of single platinum nanoparticles on a carbon ultramicroelectrode (UME). The electrocatalytic signal of a Pt nanoparticle on a cathodic pole of a bipolar electrode is coupled to the ECL signal on the anodic pole generating a transient optical signal. Correlated amperometric (i-t) and ECL (count-t) traces are then compared to determine critical parameters which influence the accurate temporal resolution of these rapid events. Our results suggest that ECL can be an effective means for spatially and temporally resolving transient redox processes when used on arrays of closed bipolar electrodes. [ABSTRACT FROM AUTHOR]

The fast Fourier transform FFT processor is an important part of the space real-time signal processing system based on field programmable gate array (FPGA). Since occupying a large amount of logical resources and storage resources, FFT processor is more vulnerable to high-energy particles in space, resulting in single event upset (SEU). This paper presents a novel FPGA scrubbing framework base on dynamic partial reconfiguration technique for a FFT processor to mitigate SEU. The proposed scheme is compared with the blind scrubbing, the reconfiguration time is reduced by 78%. Then, the resource utilisation is 61.5% less than triple modular redundancy scheme. This paper also presents a DPR controller for FFT processor, which is evaluated in terms of hardware resources and reconfiguration time. A comparison to the Xilinx PRC IP shows that multipath delay feedback FFT controller saves 38.6% resources. [ABSTRACT FROM AUTHOR]

The effects of electromagnetic and particle irradiation on two-dimensional materials (2DMs) are discussed in this review. Radiation creates defects that impact the structure and electronic performance of materials. Determining the impact of these defects is important for developing 2DM-based devices for use in high-radiation environments, such as space or nuclear reactors. As such, most experimental studies have been focused on determining total ionizing dose damage to 2DMs and devices. Total dose experiments using X-rays, gamma rays, electrons, protons, and heavy ions are summarized in this review. We briefly discuss the possibility of investigating single event effects in 2DMs based on initial ion beam irradiation experiments and the development of 2DM-based integrated circuits. Additionally, beneficial uses of irradiation such as ion implantation to dope materials or electron-beam and helium-beam etching to shape materials have begun to be used on 2DMs and are reviewed as well. For non-ionizing radiation, such as low-energy photons, we review the literature on 2DM-based photo-detection from terahertz to UV. The majority of photo-detecting devices operate in the visible and UV range, and for this reason they are the focus of this review. However, we review the progress in developing 2DMs for detecting infrared and terahertz radiation. [ABSTRACT FROM AUTHOR]

The kinetic modeling of Fischer-Tropsch Synthesis on an iron catalyst starting from experimental data collected in a spinning basket reactor and proceeding through the Single Event approach to limit the number of independent parameters is reported. The elementary steps are based on the carbide mechanism with hydrogen assisted CO insertion and CH2 as the growth monomer. The evolution with the chain length of alkane-, alkene-, and alcohol-selectivities in the synthesis product and their exponential-like behavior is fundamentally generated by accounting for the effect of the structure of reactants and transition state intermediates on the rate coefficients. The olefin readsorption is included in the model but its influence on the product distribution is found to be negligible. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1668-1682, 2016 [ABSTRACT FROM AUTHOR]

Power metal-oxide semiconductor field-effect transistors (MOSFETs) are increasingly used in the space probes where the environment is composed of various kinds of particles. Thus, it is essential to study the influence of the natural radiation environment on the electrical behaviour of MOSFETs in space. This study presents two-dimensional numerical simulation results, which investigates the sensitive volume, triggering criteria and characteristics of single-event burnout (SEB) and single-event gate rupture (SEGR) for the split-gate enhanced power U-shape MOSFET (SGE-UMOS). In addition, the comparison of the standard Trench-UMOS and SGE-UMOS for both SEB and SEGR simulation results is investigated. The SGE-UMOS shows an improved SEB performance than the standard Trench-UMOS with a larger safe operating area. The SGE-UMOS can also contribute to protect against SEGR compared with standard Trench-UMOS. [ABSTRACT FROM AUTHOR]

Fault slip rate is one of the most important subjects in active tectonics research, which reveals the activity and seismic potential of a fault. Due to the improvement of dating precision with the development of dating methods, Holocene geological markers, even the young markers of thousands or hundreds of years old, are widely used in fault slip rate calculation. Usually, uncertainties from a single event and erosion of the accumulated offsets are involved in fault slip rate determination. Two types of uncertainties are related to a single event; the first is the time elapsed since the latest (the most recent) event; the second is the period since the formation of the geological marker to the occurrence of the first event. High-slip-rate faults are more sensitive to these uncertainties than low-slip-rate faults. In this study, we studied quantitatively the effects of a single event on fault slip rate following the three classic earthquake models: the characteristic earthquake, uniform slip and variable slip models. We suggest that the erosion of the accumulated offset-lateral erosion on a strike-slip fault, should also be considered in fault slip estimation. Therefore, we propose a differential method to obtain a reliable fault slip rate. In the differential method, the slip rate is the ratio of offset differentials and corresponding age differentials between the older and younger terraces along strike-slip faults. This kind of differential method could avoid the uncertainties from the first and latest events, as well as that from the lateral erosion. By applying the differential method, we got the revised slip rates of ∼5-10 mm/year on the Altyn Tagh and Kunlun faults. These low slip rates could fit previous geodetic and geological fault slip rates and shortening rates as well as the millennial recurrence intervals of strong earthquakes along the major segments of these faults. [ABSTRACT FROM AUTHOR]

Summary: SET has become the main concern of radiation effect researchers as technology scales down and increasing sensitivity of modern integrated circuits. Transient response induced by heavy‐ion, especially the impact of parasitic bipolar amplification in both the NMOS transistor and the CMOS inverter, is investigated in this paper. The bipolar effect of the bulk NMOS transistor has been studied through transient current measurements by using 3‐D simulation. The simulation of a 3‐D structure has confirmed the enhancement effect due to the bipolar‐like structure inherent to the NMOS transistor. With regard to the CMOS inverter, waveforms of transient voltage pulse are fully measured via 2‐D mixed‐mode simulation. In addition, the impact of LET on transient voltage pulse amplitude and width is analyzed; also, the effect of load capacitance on voltage pulse amplitude is discussed as well. The 2‐D mixed‐mode simulation results indicate that SET pulse amplitude increases with the value of LET due to enhancement of drift, while SET pulse width increases with the LET for the reason of more significant parasitic bipolar amplification effect. In addition, SET pulse amplitude increases monotonically with the load capacitance. This paper further investigates the bipolar amplification mechanism in bulk MOSFET and analyzes the variation of transient voltage pulse in different conditions in deep submicron device. [ABSTRACT FROM AUTHOR]

Technology scaling results in that, soft errors, due to radiation-induced single event double-upset (SEDU) that affects double nodes through charge sharing, become a prominent concern in nanoscale CMOS technology. Existing hardened schemes suffer from being not fully SEDU-immune, or perform with too large cost penalties regarding propagation delay, silicon area, and power dissipation. A novel highperformance, low-cost, and fully SEDU-immune latch, referred to as HSMUF, is presented to tolerate SEDU when any arbitrary combination pair of nodes is affected by a particle striking. The latch mainly consists of a clock gating-based triple path DICE and a multiple-input Muller C-element. Simulation results demonstrate the SEDU-immunity and a 99.73% area-power-delay product saving for the HSMUF latch, compared with the SEDU fully immune DNCS-SEUT latch.Q [ABSTRACT FROM AUTHOR]

A low-cost fault-tolerant finite impulse response (FIR) filter is presented to save logic resources. Based on the redundant residue number system (RRNS), it eliminates soft errors generated by single event upset (SEU) in space applications, which requires only one three-moduli set residue to binary converter based on the Chinese remainder theorem. When a soft error happens, only one small-sized first-in-first-out and rollback operations are needed to refresh the FIR filter corrupted by SEU. Theoretical analysis and fault injections are performed to validate that there is no fault missing event. In addition, the proposed scheme can save 21% cell area compared with the conventional RRNS method. [ABSTRACT FROM AUTHOR]