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This paper studies the integration of two successful hardware-supported security mechanisms: capabilities and enclaved execution. Capabilities are a powerful and flexible security mechanism for implementing fine-grained memory access control and compartmentalizing untrusted or buggy software components. Capabilities have a long history but have gained significant momentum recently, as evidenced by ARM’s experimental Morello processor that supports the Capability Hardware Enhanced RISC Instructions (CHERI). Enclaved execution is a popular mechanism for dynamically creating Trusted Execution Environments (TEEs), called enclaves. Enclaves are isolated execution contexts that protect the integrity and confidentiality of software in the enclave (even against compromised system software) and that support attestation. Integrating capabilities and enclaved execution in a single processor is challenging because they overlap partially in their security objectives, and a clean integration should unify the way in which these overlapping objectives are achieved. In addition, it is not obvious how attestation should interact with capabilities. In this paper, we propose CHERI-TrEE: a novel design for a processor that cleanly integrates support for both capabilities and enclaved execution. CHERI-TrEE targets low-end embedded systems without virtual memory. We show that CHERI-TrEE is greater than the sum of its parts by showing how it naturally supports useful features that have traditionally been hard to support in enclaved execution, like dynamically growing and shrinking enclaves, non-contiguous and nested enclaves, sharing of memory between enclaves etc. We implement our proposal both in hardware on a RISC-V processor, as well as in a small software hypervisor on top of ARM Morello, and evaluate impact on performance and hardware resources. ispartof: pages:1143-1159 ispartof: Proceedings of the 8th IEEE European Symposium on Security and Privacy pages:1143-1159 ispartof: 8th IEEE European Symposium on Security and Privacy location:Delft date:3 Jul - 7 Jun 2023 status: published

In this paper, we propose a simple attention mechanism, we call box-attention. It enables spatial interaction between grid features, as sampled from boxes of interest, and improves the learning capability of transformers for several vision tasks. Specifically, we present BoxeR, short for Box Transformer, which attends to a set of boxes by predicting their transformation from a reference window on an input feature map. The BoxeR computes attention weights on these boxes by considering its grid structure. Notably, BoxeR-2D naturally reasons about box information within its attention module, making it suitable for end-to-end instance detection and segmentation tasks. By learning invariance to rotation in the box-attention module, BoxeR-3D is capable of generating discriminative information from a bird's-eye view plane for 3D end-to-end object detection. Our experiments demonstrate that the proposed BoxeR-2D achieves state-of-the-art results on COCO detection and instance segmentation. Besides, BoxeR-3D improves over the end-to-end 3D object detection baseline and already obtains a compelling performance for the vehicle category of Waymo Open, without any class-specific optimization. Code is available at https://github.com/kienduynguyen/BoxeR., Comment: In Proceeding of CVPR'2022

Surface transportation accounts for a large fraction of greenhouse gas emissions around the world. Vehicles powered by internal combustion engines are becoming increasingly fuel efficient and produce less emissions through a number of technological improvements. One technology category is providing real-time “eco-driving” feedback to drivers, so that they drive more efficiently. Since hard accelerations have a major effect on vehicle fuel consumption and emissions, some eco-driving systems have been developed to provide drivers with feedback through the accelerator pedal in order to mitigate these events. This study evaluates one such system called the Reactive Force Pedal (RFP) that provides different degrees of force feedback to the driver. This study examined two levels of force feedback (LOW and HIGH) that were applied to 40 drivers while driving on a prescribed route in Southern California. Detailed driving data (speed, acceleration, fuel consumption, etc.) were collected for baseline, LOW RFP, and HIGH RFP settings, and subsequently compared. The data were also used to compare different emission models in order to gain insight on future scenario estimation methods. The results show that there is 2% - 3% improvement in fuel economy with the LOW setting, and approximately 3% - 5% improvement with the HIGH setting, when consider positive acceleration events. The technology has different effects among different drivers.

The advent of multi-PW laser facilities world-wide opens new opportunities for nuclear physics. With this perspective, we developed a high efficiency neutron counter taking into account the specifics of a high intensity laser environment. Using GEANT4 simulations and prototype testings, we report on the design of a modular neutron-counter based on boron-10 enriched scintillators and high-density polyethylene moderator. This detector has been calibrated using a plutonium-beryllium neutron source and commissioned during an actual neutrons producing laser experiment at theLULI2000 facility (France). An overall efficiency of 4.37(59)% has been demonstrated during calibration with a recovery time of a few hundreds microseconds after laser-plasma interaction. We also tested using units of this detector in neutron time-of-flight configuration during the commissioning of the 1PW arm of the Apollon laser facility. Neutrons produced by the conversion of proton accelerated by the 1PW arm of the Apollon facility have been detected, of which we will present preliminary results.

The use of 3D printing in the body has a range of biomedical applications, including development of implantable antennas and other electronics. Using a biocompatible thermally crosslinked polymer material and a coaxial heating applicator, wire-like configurations could be “printed” directly into the body. This paper evaluates the heating time required to solidify the biopolymer in two concentrations of phosphate buffer solution.

Unmanned aerial vehicles (UAVs) have become a popular and useful tool for aerial mapping in a variety of domains. A limitation to even further adoption is the lack of scalability in many current methods, which require considerable manual work to incorporate new data. Inconsistent collection and processing of data can additionally prevent later consolidation and comparison of data across numerous dates and sites. An automated image processing workflow has been developed to allow end-users to plan and execute UAV flights with the end goal of publishing consistent and reliable data products. An example use case focusing on object detection for plant phenotyping shows the effectiveness of this workflow. Here, it is demonstrated that by utilizing this workflow, an end user is capable of producing consistent quality training images and annotations in a standardised way, allowing for the fast production and inference of new application models. As more data is adopted into the workflow, these models can be further improved by leveraging the additional data, which can reduce future training requirements and allow for progressively faster and more robust inference.

As technologies continue to shrink, memory system failure rates have increased, demanding support for stronger forms of reliability. In this work, we take inspiration from the two-tier approach that decouples correction from detection and explore a novel extrapolation. We propose Dvé, a hardware-driven replication mechanism where data blocks are replicated in 2 different sockets across a cache-coherent NUMA system. Each data block is also accompanied by a code with strong error detection capabilities so that when an error is detected, correction is performed using the replica. Such an organization has the advantage of offering two independent points of access to data which enables: (a) strong error correction that can recover from a range of faults affecting any of the components in the memory, upto and including the memory controller, and (b) higher performance by providing another nearer point of memory access. Dvé realizes both of these benefits via Coherent Replication, a technique that builds on top of existing cache coherence protocols for not only keeping the replicas in sync for reliability, but also to provide coherent access to the replicas during fault-free operation for performance. Dvé can flexibly provide these benefits on-demand by simply using the provisioned memory capacity which, as reported in recent studies, is often underutilized in today's systems. Thus, Dvé introduces a unique design point that offers higher reliability and performance for workloads that do not require the entire memory capacity.