High throughput accelerator interface framework for a linear time-multiplexed FPGA overlay

Coarse-grained FPGA overlays improve design productivity through software-like programmability and fast compilation. However, the effectiveness of overlays as accelerators is dependent on suitable interface and programming integration into a typically processor-based computing system, an aspect which has often been neglected in evaluations of overlays. We explore the integration of a time-multiplexed FPGA overlay over a server-class PCI Express interface. We show how this integration can be optimised to maximise performance, and evaluate the area overhead. We also propose a user-friendly programming model for such an overlay accelerator system

Measuring Friction at an Interface Using Nonlinear Ultrasonic Response

Contacts of rough surfaces are present in almost all machines and mechanical components. Friction at the rough interface cause energy dissipation, wear and damage of surfaces. Engineers are interested in knowing the frictional conditions at contact interfaces. Despite friction being such a fundamental phenomenon, it is surprisingly difficult to measure reliably as results depend on the test method measurement environment. Methods have been developed to measure the friction and sliding contact tribometers are devised mostly in a laboratory environment. Their applications in measuring friction in–situ in a real contact is a challenge. Therefore, the aim of this research is to develop an ultrasonic method to measure friction and friction coefficient in-situ in a contact interface. Ultrasonic methods developed for non-destructive testing have been used to measure tribological parameters, such as oil film thickness, viscosity and pressure, in-situ bearings and machines. In conventional ultrasonic techniques, pulses are low power and when they strike an interface they do not result in a change in the contact state. The process is linear and elastic. However, high power sound waves can cause opening or closing of an interface, or interfacial slip; this is non-linear. Recently Contact Acoustic Nonlinearity (CAN) has drawn interest due to its potential in the non-destructive evaluation. When high power bulk shear ultrasound propagates through a compressed rough contact interface, higher order frequency components, higher odd order harmonics (3f, 5f, etc.) are generated in both transmitted and reflected waves. The nonlinear nature of the stick-slip phenomenon in friction may be the source of nonlinearity. In this study, nonlinearity due to the interaction of a shear ultrasonic wave with a frictional interface has been initially investigated numerically. A one-dimensional numerical model has been employed to understand contact nonlinearity generation and its dependence on incident ultrasonic amplitude, contact pressure and friction coefficient. The third harmonic increases and then decreases when contact stress rises, which suggests that nonlinearity generation due to the ‘stick-slip’ motion occurs at low contact stress and is restricted at high contact pressure. Harmonic generation at the contact was secondly investigated experimentally using a high frequency nonlinear ultrasonic technique. Methods were developed to separate the contact nonlinearity from the measured ultrasonic nonlinearity. Contact nonlinearity originating from a rough interface are assessed under various test conditions. Experimental measurement shows good agreement with the numerically computed nonlinearity. Two strategies were developed to estimate the friction coefficient using experimentally measured contact nonlinearity in conjunction with the numerical computation. The ultrasonically measured friction coefficient agrees reasonably with the sliding test results and published data. Using the contact nonlinearity, the ultrasonic method shows the usefulness in measuring the friction coefficient in-situ in a contact interface

The ZZ resonance, inelastic dark matter, and new physics anomalies in the Simple Extension of the Standard Model (SESM) with general scalar potential

We consider the generic scalar potential with CP-violation, and study the $Z$ resonance and inelastic dark matter in the Simple Extension of the Standard Model (SESM), which can explain the dark matter as well as new physics anomalies such as the B physics anomalies and muon anomalous magnetic moment, etc. With the new scalar potential terms, we obtain the mass splittings for the real and imaginary parts of scalar fields. And thus we can have the DM co-annihilation process mediated by $Z$ boson, which couples exclusively to the CP-even and CP-odd parts of scalar fields. This is a brand new feature compared to the previous study. For the CP conserving case, we present the viable parameter space for the Higgs and $Z$ resonances, which can explain the B physics anomalies, muon anomalous magnetic moment, and dark matter relic density, as well as evade the constraint from the XENON1T direct detection simultaneously. For the CP-violating case, we consider the inelastic dark matter, and study four concrete scenarios for the inelastic DM-nucleon scatterings mediated by the Higgs and $Z$ bosons in details. Also, we present the benchmark points which satisfy the aforementioned constraints. Furthermore, we investigate the constraints from the dark matter-electron inelastic scattering processes mediated by the Higgs and $Z$ bosons in light of the XENONnT data. We show that the constraint on the $Z$ mediated process is weak, while the Higgs mediated process excludes the dark matter with mass around several MeV.Comment: 22 pages, 6 figures, 5 table

FGO-ILNS: Tightly Coupled Multi-Sensor Integrated Navigation System Based on Factor Graph Optimization for Autonomous Underwater Vehicle

Multi-sensor fusion is an effective way to enhance the positioning performance of autonomous underwater vehicles (AUVs). However, underwater multi-sensor fusion faces challenges such as heterogeneous frequency and dynamic availability of sensors. Traditional filter-based algorithms suffer from low accuracy and robustness when sensors become unavailable. The factor graph optimization (FGO) can enable multi-sensor plug-and-play despite data frequency. Therefore, we present an FGO-based strapdown inertial navigation system (SINS) and long baseline location (LBL) system tightly coupled navigation system (FGO-ILNS). Sensors such as Doppler velocity log (DVL), magnetic compass pilot (MCP), pressure sensor (PS), and global navigation satellite system (GNSS) can be tightly coupled with FGO-ILNS to satisfy different navigation scenarios. In this system, we propose a floating LBL slant range difference factor model tightly coupled with IMU preintegration factor to achieve unification of global position above and below water. Furthermore, to address the issue of sensor measurements not being synchronized with the LBL during fusion, we employ forward-backward IMU preintegration to construct sensor factors such as GNSS and DVL. Moreover, we utilize the marginalization method to reduce the computational load of factor graph optimization. Simulation and public KAIST dataset experiments have verified that, compared to filter-based algorithms like the extended Kalman filter and federal Kalman filter, as well as the state-of-the-art optimization-based algorithm ORB-SLAM3, our proposed FGO-ILNS leads in accuracy and robustness

The Right-Handed Slepton Bulk Region for Dark Matter in Generalized No-scale F\mathcal{F}-SU(5)SU(5) with Effective Super-Natural Supersymmetry

We propose Generalized No-Scale Supergravity, the simplest scenario for Effective Super-Natural Supersymmetry, naturally solving the supersymmetry electroweak fine-tuning problem and including natural dark matter. A light right-handed slepton bulk region is realized in $\mathcal{F}$-$SU(5)$ and the pMSSM. The bulk may be beyond the LHC reach, though can be probed at the 1000-day LUX-ZEPLIN, Future Circular Collider (FCC-ee) at CERN, Circular Electron Positron Collider (CEPC), and Hyper-Kamiokande.Comment: 7 pages, 5 Figures, 1 Table. v2 includes results from ATLAS soft lepton SUSY search and expected sensitivity of 1000-day LUX-ZEPLI

A time-multiplexed FPGA overlay with linear interconnect

Coarse-grained overlays improve FPGA design pro- ductivity by providing fast compilation and software like pro- grammability. Soft processor based overlays with well-defined ISAs are attractive to application developers due to their ease of use. However, these overlays have significant FPGA resource overheads. Time multiplexed (TM) CGRA-like overlays represent an interesting alternative as they are able to change their behavior on a cycle by cycle basis while the compute kernel executes. This reduces the FPGA resource needed, but at the cost of a higher initiation interval (II) and hence reduced throughput. The fully flexible routing network of current CGRA-like overlays results in high FPGA resource usage. However, many application kernels are acyclic and can be implemented using a much simpler linear feed-forward routing network. This paper examines a DSP block based TM overlay with linear interconnect where the overlay architecture takes account of the application kernels’ characteristics and the underlying FPGA architecture, so as to minimize the II and the FPGA resource usage. We examine a number of architectural extensions to the DSP block based functional unit to improve the II, throughput and latency. The results show an average 70% reduction in II, with corresponding improvements in throughput and latency

Validation of Konsung Compass 2000 Dry Biochemical Analyzer

Dry biochemical analyzers have been increasingly popular in many tests by primary hospitals, field hospitals and other areas subject to economic and medical underdevelopment as well as poor transportation. With the increasing demand for POCT in primary medical care around the world, upgrading of dry biochemical analyzers has been a hot topic in technical research. Against such context, Konsung Compass2000 dry biochemical analyzer, a POCT system with high precision and accuracy, is developed. Furthermore, the upgraded dry biochemical analyzers can, in a more convenient and accurate way, monitor glucose, lipid and other indices affecting the course of chronic diseases