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Joint absence in people with upper-limb-difference leads to compensatory motions. Such compensation has long been a topic of study, but typically only for a single object/user layout, which is unlikely to spatially generalize. We seek to understand how motion varies over a planar workspace for different target orientations and wrist mobility conditions. We therefore present a study that records arm and torso pose during grasping of 49 equally spaced cylindrical targets. Furthermore, we seek to validate the research practice of using wrist-immobilizing bypass sockets on able-bodied participants to simulate prostheses without wrists. Participants were 2 transradial amputees and 7 able-bodied individuals who conducted the study with and without wrist braces, generating 2450 trajectories. Heat-maps illustrate variation over the workspace in Mean Joint Angle, Range of Joint Motion and Distance Travelled by Body Segment. Results indicate that greater wrist restriction primarily exacerbated shoulder internal rotation and elbow flexion, not the trunk. We observed that bypass sockets do not fully simulate amputee behavior. Furthermore, amputee reaching with their intact limb is different to the reaching motion of normative participants, implying that transradial limb-difference affects both sides of the body. Differences in participant behavior were also observed between horizontal and vertical target orientations.

ARINC-653, a standard of avionics software platform, defines the sampling communication port that provides only the latest message while discarding old messages. This sampling port is particularly efficient at transmitting sensing data that reflects the actual state of target system without message queueing delay. In this letter, we implement the ARINC-653 sampling port by exploiting remote direct memory access (RDMA) over Ethernet that can directly move data to/from remote memory without CPU intervention on the remote node. We propose two different designs to utilize two-sided RDMA and one-sided RDMA operations, respectively. Performance measurement results show that the sampling port over one-sided RDMA provides lower-communication latency, stronger temporal partitioning, and better-message timeliness than two-sided RDMA and Berkeley sockets-based implementations. [ABSTRACT FROM AUTHOR]

Objectives: There are no studies related to the use of PRF associated with cyanoacrylates in fresh post-extraction sockets. Thus, the aim of this study was to assess the effect of ethyl-cyanoacrylate combined with PRF in fresh sockets of rabbits subjected to anticoagulant therapy. Methods: Twelve adults rabbits were selected and premedicated with heparin 1 week before surgery to induce and simulate anticoagulant therapy. Upper and lower first premolars on the right side were extracted and then were divided into four groups of three animals each, with the groups distributed according to the type of intervention in the sockets (n = 6): (1) clot and suture (control); (2) PRF and suture; (3) clot and ethyl-cyanoacrylate; (4) PRF and ethyl-cyanoacrylate. At 12 weeks, the animals were sacrificed and the sockets were analyzed histologically and quantitatively. Total bone area, inflammation infiltrate, and adhesive remnants were assessed. Results: No remnants of adhesive were found in the samples. Groups 1 and 2 showed the highest bone area (G1 = 37.87% ± 17.86; G2 = 30.31 ± 9.36) with significant differences to those treated with ethyl-cyanoacrylate adhesive (G3 = 26.6% ± 11.82; G4 = 24.29% ± 6.25). Conclusions: The groups that used ethyl-cyanoacrylate as a closure method in sockets exhibited less bone area than the groups that used sutures. Both groups that used PRF as therapy did not show a significant improvement in bone healing at 12 weeks compared with the clot groups. [ABSTRACT FROM AUTHOR]

Intelligent transfemoral prostheses, which have recently been studied, are equipped with a microcontroller, providing appropriate motion functions for their walking environments. Thus, studies have been conducted to estimate user intentions in locomotion movements by applying biomechanical sensors inside the socket. Among them, a pressure sensor is used to determine the intentions of locomotion movements through changes in the internal pressure of the prosthetic socket. However, existing studies have a problem in that the reproducibility of pressure change data is degraded due to the non-detection and saturation of the pressure measurement value. Accordingly, this study proposes a fabrication method for a wide and flexible pressure sensor that can solve this problem and a method for the identification of user intentions in locomotion movements using it. The proposed system was fabricated with Velostat film, which has a smaller noise impact and can be fabricated in various sizes and shapes. The fabricated sensor was attached to four points inside the socket, confirming the possibility of detecting the intention of six movements according to the multi-critical detection method. The proposed pressure-sensor-based intention detection system can be applied individually by prosthetic users through simple tasks. Moreover, it will be universally applicable for commercialization. [ABSTRACT FROM AUTHOR]

Prosthetic hands have significant potential to restore the manipulative capabilities and self-confidence of amputees and enhance their quality of life. However, incompatibility between prosthetic devices and residual limbs can lead to secondary injuries such as skin pressure ulcers and restricted joint motion, contributing to a high prosthesis abandonment rate. To address these challenges, this study introduces a data-driven design framework (D3Frame) utilizing a multi-index optimization method. By incorporating motion/ pressure data, as well as clinical criteria such as pain threshold/ tolerance, from various anatomical sites on the residual limbs of amputees, this framework aims to optimize the structural design of the prosthetic socket, including the Antecubital Channel (AC), Lateral Epicondylar Region Contour (LC), Medial Epicondylar Region Contour (MC), Olecranon Region Contour (OC), Lateral Flexor/ Extensor Region (LR), and Medial Flexor/ Extensor Region (MR). Experiments on five forearm amputees verified the improved adaptability of the optimized socket compared to traditional sockets under three load conditions. The experimental results revealed a modest score enhancement on standard clinical scales and reduced muscle fatigue levels. Specifically, the percent effort of muscles and slope value of mean/ median frequency decreased by 19%, 70%, and 99% on average, respectively, and the average values of mean/ median frequency in the motion cycle both increased by approximately 5%. The proposed D3Frame in this study was applied to optimize the structural aspects of designated regions of the prosthetic socket, offering the potential to aid prosthetists in prosthesis design and, consequently, augmenting the adaptability of prosthetic devices. [ABSTRACT FROM AUTHOR]

The primary goal of rehabilitation for individuals with lower limb amputation, particularly those with unilateral transfemoral amputation (uTFA), is to restore their ability to walk independently. Effective control of the center of pressure (COP) during gait is vital for maintaining balance and stability, yet it poses a significant challenge for individuals with uTFA. This study aims to study the COP during gait in individuals with uTFA and elucidate their unique compensatory strategies. This study involved 12 uTFA participants and age-matched non-disabled controls, with gait and COP trajectory data collected using an instrumented treadmill. Gait and COP parameters between the control limb (CL), prosthetic limb (PL), and intact limb (IL) were compared. Notably, the mediolateral displacement of COP in PL exhibited significant lateral displacement compared to the CL from 30% to 60% of the stance. In 20% to 45% of the stance, the COP forward speed of PL was significantly higher than that of the IL. Furthermore, during the initial 20% of the stance, the vertical ground reaction force of PL was significantly lower than that of IL. Additionally, individuals with uTFA exhibited a distinct gait pattern with altered duration of loading response, single limb support, pre-swing and swing phases, and step time. These findings indicate the adaptability of individuals with uTFA in weight transfer, balance control, and pressure distribution on gait stability. In conclusion, this study provides valuable insights into the unique gait dynamics and balance strategies of uTFA patients, highlighting the importance of optimizing prosthetic design, alignment procedures, and rehabilitation programs to enhance gait patterns and reduce the risk of injuries due to compensatory movements. [ABSTRACT FROM AUTHOR]

The last few years witnessed radical improvements in lower-limb prostheses. Researchers have presented innovative solutions to overcome the limits of the first generation of prostheses, refining specific aspects which could be implemented in future prostheses designs. Each aspect of lower-limb prostheses has been upgraded, but despite these advances, a number of deficiencies remain and the most capable limb prostheses fall far short of the capabilities of the healthy limb. This article describes the current state of prosthesis technology; identifies a number of deficiencies across the spectrum of lower limb prosthetic components with respect to users’ needs; and discusses research opportunities in design and control that would substantially improve functionality concerning each deficiency. In doing so, the authors present a roadmap of patients related issues that should be addressed in order to fulfill the vision of a next-generation, neurally-integrated, highly-functional lower limb prosthesis. [ABSTRACT FROM AUTHOR]

Digitising prosthetic sockets and moulds is critical for advanced fabrication techniques enabling reduced lead times, advanced computer modelling, and personalised design history. Current 3D scanners are expensive (>GBP 5000) and difficult to use, restricting their use by prosthetists. In this paper, we explore the use and accuracy of smartphone photogrammetry (

Gallium is one of the most desirable, yet less known, interconnects considered in the semiconductor industry. Good electrical conductivity and high stretchability of the liquid metal makes it very attractive for many applications. It allows components to be assembled or disaggregated like Lego blocks without any external forces or energy. The focus of this article is to shed light on intrinsic reliability degradation mechanisms for components that use liquid metal interconnects. As a starting reference to field reliability risk evaluations, the authors focus on common/controlled use conditions. Environments studied include standard test evaluation procedures like thermal aging (sustained exposure to high temperature over time), thermal cycling, current carrying capability, and finally functional product life cycle testing. Studies reveal that the interconnect has very distinct failure mechanisms and unique advantageous/disadvantageous over existing interconnects. Fundamental knowledge gained in this study is expected to help 1) drive future architectures, 2) material/design changes to address any limitations, and 3) finally new qualification methods/standards that account for the unique failure mechanisms. [ABSTRACT FROM AUTHOR]

We present our automated real-time socket inspection system capable of detecting an assortment of defects including metallic and liquid staining, loose capacitors and pins, and other debris and foreign material (FM). Our test tools pick and place manufactured units into sockets for electrical testing. Any debris accumulated inside the test sockets will likely damage subsequent units until the defective socket is replaced. To quickly capture in-situ defects and mitigate further damage, we equipped each pick-and-place arm with a new vision system designed to fit within the existing tool. The tight footprint constraints required a highly compact imaging system which resulted in a variety of image artifacts, creating several unique challenges. Our inspection algorithm utilizes a variety of advanced computer vision and machine learning techniques to normalize images, extract and match features, register the images, suppress unwanted artifacts, and detect defects. The detected changes are then sent to a deep learning classifier to further filter between true defects and natural socket deterioration. The flagged socket images can be manually dispositioned by the user and the socket can be sent for repair or cleaning as needed. [ABSTRACT FROM AUTHOR]

Understanding the lower-limb coordination of individuals with unilateral transfemoral amputation (uTFA) while walking is essential to understand their gait mechanisms. Continuous relative phase (CRP) analysis provides insights into gait coordination patterns of the neuromusculoskeletal system based on movement kinematics. Fourteen individuals with uTFA and their age-matched non-disabled individuals participated in this study. Kinematic data of the lower limbs of the participants were collected during walking. The joint angles, segment angles, and CRP values of the thigh-shank and shank-foot couplings were investigated. The curves among the lower limbs of the participants were compared using a statistical parametric mapping test. Compensatory strategies were found in the lower limbs from coordination patterns. In thigh-shank coupling, although distinct coordination traits in stance and swing phases among the lower limbs were found, the lower limbs in both groups were discovered to remain in a similar coordination pattern during gait. For individuals with uTFA, in shank-foot coupling, intact limbs demonstrated a short period of foot-leading pattern which was significantly different from that of the other limbs during mid-stance to compensate for the weaker force generation by prosthetic limbs. The findings offer normative coordination patterns on the walking of individuals with uTFA, which could benefit prosthetic gait rehabilitation and development. [ABSTRACT FROM AUTHOR]

Intelligent transfemoral prostheses, which have recently been studied, are equipped with a microcontroller, providing appropriate motion functions for their walking environments. Thus, studies have been conducted to estimate user intentions in locomotion movements by applying biomechanical sensors inside the socket. Among them, a pressure sensor is used to determine the intentions of locomotion movements through changes in the internal pressure of the prosthetic socket. However, existing studies have a problem in that the reproducibility of pressure change data is degraded due to the non-detection and saturation of the pressure measurement value. Accordingly, this study proposes a fabrication method for a wide and flexible pressure sensor that can solve this problem and a method for the identification of user intentions in locomotion movements using it. The proposed system was fabricated with Velostat film, which has a smaller noise impact and can be fabricated in various sizes and shapes. The fabricated sensor was attached to four points inside the socket, confirming the possibility of detecting the intention of six movements according to the multi-critical detection method. The proposed pressure-sensor-based intention detection system can be applied individually by prosthetic users through simple tasks. Moreover, it will be universally applicable for commercialization.

Forearm amputees can use body-powered hooks and myoelectric hands for their daily activities. The body-powered hooks are suitable for delicate manipulation. However, their appearance is not always preferred by amputees, and a harness to pull a control cable is not easy to wear. Although the myoelectric hands have a natural appearance similar to the human hand and can be intuitively controlled by a myoelectric control system, they are not easy to try out and are heavy. This paper reports on the Finch, a prosthetic arm with three opposing fingers controlled by a muscle bulge. The aim of developing the Finch is to realize a lightweight prosthetic arm that is easy to wear and use. Three opposing fingers are controlled according to the degree of muscle bulge measured with a muscle bulge sensor on the user’s forearm caused by muscle contraction. A supporter socket, consisting of a resin socket frame and a fabric supporter, allows easy fitting. A simple design using a linear actuator and 3D-printed parts achieved light weight (330 g) and low cost. Six functional tests and user tests using Southampton Hand Assessment Procedure showed that the Finch had a practical function that could be used in daily activities. [ABSTRACT FROM AUTHOR]

Background: Participants in Sierra Leone received a Fused Filament Fabrication (FFF)-printed transtibial prosthetic socket. Follow-up was conducted on this group over a period of 21 months. To investigate the failure of some of the FFF-printed transtibial sockets, further strength investigation is desired. Methods: A finite element (FE) analysis provided an extensive overview of the strength of the socket. Using follow-up data and FE analyses, weak spots were identified, and the required optimization/reinforcement of the socket wall was determined. Results: Five sockets with a 4 mm wall thickness were tested by five participants. The strength of the 4 mm prosthetic socket seemed to be sufficient for people with limited activity. The 4 mm sockets used by active participants failed at the patella tendon or popliteal area. One socket with a wall thickness of 6 mm was used by an active user and remained intact after one year of use. An FE analysis of the socket showed high stresses in the patella tendon area. An increased wall thickness of 7 mm leads to a decrease of 26% in the stress corresponding to the observed failure in the patella tendon area, compared to the 4 mm socket. Conclusions: Follow-up in combination with an FE analysis can provide insight into the strength of the transtibial socket. In future designs, both the patella tendon and popliteal area will be reinforced by a thickened trim line of 7 mm. A design with a thickened trimline of 7 mm is expected to be sufficiently strong for active users. Another follow-up study will be performed to confirm this. [ABSTRACT FROM AUTHOR]

In this technical report, we focus on reproducing the results reported in the paper “MemXCT: Memory-Centric X-ray CT Reconstruction with Massive Parallelization” [1]. MemXCT is a scalable approach to X-ray Computed Tomography reconstruction which removes redundant computation. We reproduced the single CPU/GPU performance as well as strong scaling experiments. We set up our configurations on Microsoft Azure CycleCloud and have two clusters. One cluster has 4 nodes with 60 CPUs on each node and the other cluster has 4 nodes with 4 NVIDIA V100 GPUs on each node. Both clusters come with InfiniBand. The original author conducted his experiments on Theta and Blue Waters supercomputers. We were able to reproduce part of the results in the original paper, however, failed to produce similar performance on other experiments. This report was submitted as part of the reproducibility challenge in SC20 Student Cluster Competition. Digital artifacts from these experiments are available at: 10.5281/zenodo.5598108. [ABSTRACT FROM AUTHOR]

This report describes The University of Texas Student Cluster Competition team’s effort to reproduce the results of “MemXCT: memory-centric X-ray CT reconstruction with massive parallelization” (Hidayetoğlu et al., 2019). The article details a new memory-centric approach that reconstructs X-ray computed tomography (XCT) from noisy raw data. In our reproduction experiments, we utilized Microsoft Azure’s CycleCloud tool to provision, orchestrate, and manage our computing cluster in the cloud. In particular, we scheduled and benchmarked reconstruction workloads using Azure’s CPU-based HC44rs and GPU-based NC12s v2 virtual machine (VM) types to evaluate the scalability properties of the reconstruction approach and the performance differences between architectures. The HC44rs VMs contained 44 Intel Xeon Platinum cores, while the NC12s v2 VM was equipped with two NVIDIA P100 GPUs. We used a recent version of Intel’s compiler stack with the MKL library for our CPU code along with CUDA 11.1 on GPUs. Overall, our results confirm the findings of the original article, demonstrating similar acceleration on GPUs and scalability properties on CPUs. Digital artifacts from these experiments are available at: 10.5281/zenodo.5598108 [ABSTRACT FROM AUTHOR]

Hidayetoğlu et al. propose a novel memory-centric algorithm to reconstruct X-ray CT images in the SC19 article entitled “MemXCT: Memory-Centric X-ray CT Reconstruction with Massive Parallelization”. They formulate the reconstruction with several SpMVs, and propose two memory-centric optimizations to improve cache locality for better memory bandwidth utilization, i.e., a two-level pseudo-Hilbert ordering and a multi-stage input buffering. In this article, we present our results on reproducing that article to show its effectiveness and generality, as part of the SC20 Student Cluster Competition Reproducibility Challenge. We reproduce the execution time and memory bandwidth tests in that article on various architectures, including Intel CPUs, AMD CPUs, and NVIDIA GPUs. We further analyze the bottleneck on different architectures by comparing the achieved memory bandwidth with the peak bandwidth on those architectures. We then reproduce the strong scaling test on CPU and GPU clusters with different scales, and use the proposed algorithm to reconstruct three new X-ray computed tomograms. [ABSTRACT FROM AUTHOR]

Greybox fuzzing has been widely used in stateless programs and has achieved great success. However, most state-of-the-art greybox fuzzers have slow speed and shallow state depth coverage in fuzzing stateful network protocol programs, which are able to remember and store the details of interactions. The existing greybox fuzzers for network protocol programs first send a series of well-defined prefix sequences of input messages and then send mutated messages to test the target state of a stateful network protocol. This process leads to a high time cost. In this paper, we propose SNPSFuzzer, a fast greybox fuzzer for stateful network protocols using snapshots. SNPSFuzzer dumps the context information when the network protocol program is in a specific state and restores it when the state needs to be fuzzed. Furthermore, we design a message chain analysis algorithm to explore more and deeper network protocol states. Our evaluation shows that compared with the state-of-the-art network protocol greybox fuzzer AFLNET, SNPSFuzzer improves the message processing speed of network protocol fuzzing by 70.7% and increases the path coverage by 20.9% on average within 24 hours. Moreover, SNPSFuzzer exposes a previously unreported vulnerability in the program Tinydtls. [ABSTRACT FROM AUTHOR]

Malicious modifications to printed circuit boards (PCBs) are known as hardware Trojans. These may arise when malafide third parties alter PCBs premanufacturing or postmanufacturing and are a concern in safety-critical applications, such as industrial control systems. In this research, we examine how data-driven detection can be utilized to detect such Trojans at run-time. We develop a flexible and reconfigurable PCB test bed derived from the popular open-source programmable logic controller (PLC) platform “OpenPLC.” We then develop a Trojan detection framework, which utilizes and analyzes multimodal side channels (e.g., timing, magnetic signals, power, and hardware performance counters). We consider defender-configurable input/output (I/O) loopback test, comparison with design-document baselines, and magnetometer-aided monitoring of system behavior under defender-chosen excitations. Our approach can extend to golden-free environments. Golden (known-good) versions of the PCBs are assumed not available, but design information, datasheets, and component-level data are available. We demonstrate the efficacy of our approach on a range of Trojans instantiated in the test bed. [ABSTRACT FROM AUTHOR]

This paper presents a system called NetKernel that decouples the network stack from the guest virtual machine and offers it as an independent module. NetKernel represents a new paradigm where network stack can be managed as part of the virtualized infrastructure. It provides important efficiency benefits: By gaining control and visibility of the network stack, operators can perform network management more directly and flexibly, such as multiplexing VMs running different applications to the same network stack module to save CPU cores, and enforcing fair bandwidth sharing. Users also benefit from the simplified stack deployment and better performance: For example mTCP can be deployed without API change to support nginx natively, and shared memory networking can be readily enabled to improve performance of colocated VMs. Testbed evaluation using 100G NICs shows that NetKernel preserves the performance and scalability of both kernel and userspace network stacks, and provides the same isolation as the current architecture. [ABSTRACT FROM AUTHOR]

In-memory key-value stores have quickly become a key enabling technology to build high-performance applications that must cope with massively distributed workloads. In-memory key-value stores (also referred to as NoSQL) primarly aim to offer low-latency and high-throughput data access which motivates the rapid adoption of modern network cards such as Remote Direct Memory Access (RDMA). In this paper, we present the fundamental design principles for exploiting RDMAs in modern NoSQL systems. Moreover, we describe a break-down analysis of the state-of-the-art of the RDMA-based in-memory NoSQL systems regarding the indexing, data consistency, and the communication protocol. In addition, we compare traditional in-memory NoSQL with their RDMA-enabled counterparts. Finally, we present a comprehensive analysis and evaluation of the existing systems based on a wide range of configurations such as the number of clients, real-world request distributions, and workload read-write ratios. [ABSTRACT FROM AUTHOR]

The majority of limb prostheses are socket mounted. For these devices, the socket is essential for adequate prosthetic suspension, comfort, and control. The socket is unique among prosthetic components as it is not usually mass-produced and must instead be custom-made for individual residual limbs by a prosthetist. The knowledge of what constitutes “good” socket fit is gained by expert prosthetists and technicians over years of experience, and rarely documented. The reliance on tacit knowledge makes it difficult to standardize the criteria for a well-fitting socket, leading to difficulties understanding the impact of socket fit. Despite its importance, the workflow for socket fitting is often overlooked in literature. Due to the customized nature of sockets, if information is provided in literature, generally only the type of socket and suspension mechanism is noted, with information regarding the fitting and manufacturing processes omitted. In this article, the concerns, issues and consequences arising from lack of upper and lower limb socket documentation are discussed from a researcher perspective, supported by healthcare professionals and socket fabrication specialists. Key changes are proposed to the way socket manufacturing and evaluation are documented to assist future research.

Objective: This paper proposes a novel method for real-time wrist kinematics identification. Method: We design the wrist kinematics regression model following a novel ellipsoidal joint formulation, which features a quaternion-based rotation constraint and 2-dimensional Fourier linear combiners (FLC) to approximate the coupled rotations and translational displacements of the wrist. Extended Kalman Filter (EKF) is then implemented to update the model in real-time. However, unlike previous studies, here we introduce a sparsity-promoting feature in the model regression through the optimality of EKF by designing a smooth $\ell 1$ -minimization observation function. This is done to ensure the best identification of key parameters, and to improve the robustness of regression under noisy conditions. Results: Simulations employ multiple reference models to evaluate the performance of the proposed approach. Experiments are later carried out on motion data collected by a lab-developed wrist kinematics measurement tool. Both simulation and experiment show that the proposed approach can robustly identify the wrist kinematics in real-time. Conclusion: The findings confirm that the proposed regression model combined with the sparsity-promoting EKF is reliable in the real-time modeling of wrist kinematics. Significance: The proposed method can be applied to generic wrist kinematics modeling problems, and utilized in the control system of wearable wrist exoskeletons. The framework of the proposed method may also be applied to real-time identification of other joints for exoskeleton control. [ABSTRACT FROM AUTHOR]

For an efficient energy management by residential users, monitoring and control of connected household appliances is required. If the consumption pattern of each of these devices is identified, then the management will be more efficient, reducing both the billing and the CO2 emissions. This paper proposes a model for the recognition of energy consumption patterns in household appliances, based on the capture of electrical parameters in connected appliances, through Smart Socket with an Intrusive Load Monitoring approach. The data acquisition system corresponds to an-Internet of Things (IoT) platform that uses Automatic Meter Reading devices, connected to a IoT-gateway via Wi-Fi to send data to an application on the web. For the recognition of the patterns, machine learning techniques are used. Accuracy results on pattern identification are obtained about 91% after applying a backpropagation method in an Artificial Neural Network in time basis. Through this work, the prediction of consumer categories in household appliances, with high levels of reliability and under multiple operating states, is reached. These results enhance the efficient management of energy in a Smart Home and Smart Cities environment [ABSTRACT FROM AUTHOR]

In this paper, we uncover a new off-path TCP hijacking attack that can be used to terminate victim TCP connections or inject forged data into victim TCP connections by manipulating the new mixed IPID assignment method, which is widely used in Linux kernel version 4.18 and beyond. Our attack has three steps. First, an off-path attacker can downgrade the IPID assignment for TCP packets from the more secure per-socket-based policy to the less secure hash-based policy, thus building a shared IPID counter that forms a side channel in the victim. Second, the attacker detects the presence of TCP connections by observing the side channel of the shared IPID counter. Third, the attacker infers sequence and acknowledgment numbers of the detected connection by observing the side channel. Consequently, the attacker can completely hijack the connection, e.g., resetting the connection or poisoning the data stream. We evaluate the impacts of our attack in the real world, and we uncover that more than 20% of Alexa top 100k websites are vulnerable to our attack. Our case studies of SSH DoS, manipulating web traffic, and poisoning BGP routing tables show its threat on a wide range of applications. Moreover, we demonstrate that our attack can be further extended to exploit IPv4/IPv6 dual-stack networks on increasing the hash collisions and enlarging vulnerable populations. Finally, we analyze the root cause and develop a new IPID assignment method to defeat this attack. We prototype our defense in Linux 4.18 and confirm its effectiveness in the real world. [ABSTRACT FROM AUTHOR]

Photonics die or integrated photonics modules co-packaged with compute engines have the potential to deliver significant improvements in power, bandwidth and reach needed to meet the computing and communication demands of data centers and other high-performance computing (HPC) systems. The challenges and solutions in co-packaging photonics modules are described through two case studies; one of a network-switch die co-packaged with socketable photonics modules and another of a Field Programmable Gate Array (FPGA) co-packaged with optical dies (tiles). The technical requirements to deliver the promise of co-packaged photonics in high volume are outlined. [ABSTRACT FROM AUTHOR]

This article presents a novel die-level, rePlaceable INtegrated CHiplet (PINCH) assembly using a socketed platform. To enable the replaceability of this tightly integrated system, an appropriate set of enabling technologies is required. To this end, the PINCH assembly incorporates a nonpermanent, off-chip interconnection system via compressible microinterconnects (CMIs) and a nonpermanent self-alignment technology using positive self-alignment structures (PSAS) in a PSAS-to-PSAS configuration. As the PSAS-to-PSAS self-alignment technology is substrate agnostic, the PINCH assembly can also incorporate heterogeneous integrated systems. This article discusses this PINCH assembly and it provides a design analysis for building this socketed system. The fabrication of all the components of the PINCH assembly (e.g., chiplet, interposer) is then performed, followed by a manual assembly process using the PSAS-to-PSAS self-alignment technology. Four-point resistance of the 150-μm pitch and 200-μm pitch CMIs is then measured after the socket is secured into the socket base of the PINCH assembly. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) have received considerable attention in dealing with severe environmental and energy crises. The capacity planning of public charging stations has been a major factor in facilitating the wide market penetration of EVs. In this paper, we present an optimization model for charging station capacity planning to maximize the fuzzy quality of service (FQoS) considering queuing behavior, blocking reliability, and multiple charging options classified by battery technical specifications. The uncertainty of the EV arrival and service time are taken into account and described as fuzzy numbers characterized by triangular membership functions. Meanwhile, an $\alpha$ -cuts-based algorithm is proposed to defuzzify the FQoS. Finally, the numerical results illustrate that a more robust plan can be obtained by accounting for FQoS. The contribution of the proposed model allows decision-makers and operators to plan the capacity of charging stations with fuzzy EV arrival rate and service rate and provide a better service for customers with different charging options. [ABSTRACT FROM AUTHOR]

Energy load monitoring via smart plugs or smart sockets has become more and more popular. Various studies have been undertaken to monitor energy consumption of household appliances and analyze the collected power data to obtain useful insights on consumers’ behaviors. The main challenge in load monitoring is to automatically recognize appliances in real time since the existing energy disaggregation process is time-consuming and labour-intensive. Although several deep learning models can achieve high accuracy on appliance classification, they usually consume large memory, hence not suitable for resources-constrained IoT devices. To resolve the issue, we demonstrate in this paper, for the first time, a novel framework named Smart Intrusive Load Monitoring based on a compact network (CompactNet), which is able to determine appliance types in real time. Specifically, our method distills the knowledge of an ensemble of large deep networks to a much more compact network. Our CompactNet accurately classifies various types of appliances, but its size is reduced by approximately eight times, making it possible to be deployed on edge IoT sensors for appliance recognition. [ABSTRACT FROM AUTHOR]

Background: Damage to bone tissue resulting from tooth extraction will cause alveolar bone resorption. Therefore, a material for preserving alveolar sockets capable of maintaining bone is required. Hydroxyapatite Gypsum Puger (HAGP) is a bio-ceramic material that can be used as an alternative material for alveolar socket preservation. The porous and rough surface of HAGP renders it a good medium for osteoblast cells to penetrate and attach themselves to. In general, bone mass is regulated through a remodeling process consisting of two phases, namely; bone formation by osteoblasts and bone resorption by osteoclasts. Purpose: This research aims to identify the effects of HAGP scaffold application on the number of osteoblasts and osteoclasts, as well as on the width of trabecular bone area in the alveolar sockets of rats. Methods: This research used Posttest Only Control Group Design. There were three research groups, namely: a group with 2.5% HAGP scaffold, a group with 5% HAGP scaffold and a group with 10% HAGP scaffold. The number of samples in each group was six. HAGP scaffold at concentrations of 2.5%, 5% and 10% was then mixed with PEG (Polyethylene Glycol). The Wistar rats were anesthetized intra-muscularly with 100 mg/ml of ketamine and 20 mg/ml of xylazine base at a ratio of 1:1 with a dose of 0.08-0.2 ml/kgBB. Extraction of the left mandibular incisor was performed before 0.1 ml preservation of HAGP scaffold + PEG material was introduced into the extraction sockets and suturing was performed. 7 days after preparation of the rat bone tissue, an Hematoxilin Eosin staining process was conducted in order that observation under a microscope could be performed. Results: There were significant differences in both the number of osteoclasts and osteoblasts between the 2.5% HAGP group, the 5% HAGP group and the 10% HAGP group (p = 0.000). Similarly, significant differences in the width of the trabecular bone area existed between the 5% HAGP group and the 10% HAGP group, as well as between the 2.5% HAGP group and the 10% HAGP group (p=0.000). In contrast, there was no significant difference in the width of the trabecular bone area between the 2.5% HAGP group and the 5% HAGP group. Conclusion: The application of HAGP scaffold can reduce osteoclasts, increase osteoblasts and extend the trabecular area in the alveolar bone sockets of rats.

As radiation detector arrays in nuclear physics applications become larger and physically more separated, the time synchronization and trigger distribution between many channels of detector readout electronics become more challenging. Clocks and triggers are traditionally distributed through dedicated cabling, but newer methods such as the IEEE 1588 Precision Time Protocol and White Rabbit allow clock synchronization through the exchange of timing messages over Ethernet. Consequently, we report here the use of White Rabbit in a new detector readout module, the Pixie-Net XL. The White Rabbit core, data capture from multiple digitizing channels, and subsequent pulse processing for pulse height and constant fraction timing are implemented in a Kintex 7 field programmable gate array (FPGA). The detector data records include White Rabbit timestamps and are transmitted to storage through the White Rabbit core’s gigabit Ethernet data path or a slower diagnostic/control link using an embedded Zynq processor. The performance is characterized by time-of-flight style measurements and by time correlation of high energy background events from cosmic showers in detectors separated by longer distances. Software for the Zynq processor can implement “software triggering,” for example to limit recording of data to events where a minimum number of channels from multiple modules detect radiation at the same time. [ABSTRACT FROM AUTHOR]

This article proposed a PairCon-simultaneous localization and mapping algorithm to construct dense maps of large-scale scenarios in real time, which is operated in an integral platform containing two personal computers (PCs). This platform can operate the mapping thread independently in a PC to guarantee sufficient memory resources. In this context, the synchronous visualization of 3-D maps can be achieved in such a platform. In contrast, traditional algorithms are limited by the short operation distance, under the requirement of simultaneous data collection and 3-D maps construction in a PC. In addition, the memory resource provided by a single PC is limited, which restricts the constructing scale of maps. Thus, we use a separate PC to construct maps independently to relieve the distance constraint and exploit the socket method to conduct the transmission of data with the point cloud. Meanwhile, we introduce the ReBlur algorithm into the semi-direct method to reduce the error accumulation of the odometer in the tracking thread, which improves the robustness performance. In addition, the method combining the memory management and DBow2 algorithm is adopted to improve the accuracy of loop detection. In the considered system, the quality of maps and the performance of the odometer are evaluated by ICL-NUIM and the datasets, such as TUM, DIODE, and so on, respectively. Finally, under the simulation environment of AirSim and Gazebo, we construct maps based on the image data of other scenarios, which is used to show the quality of the construction. [ABSTRACT FROM AUTHOR]

The open-source hardware community contributes a variety of processors and accelerators, but combining them effectively into a complete System-on-Chip (SoC) remains a difficult task. We present a design flow for the seamless hardware and software integration of accelerators into a complete SoC and for its evaluation through rapid FPGA-based prototyping. By leveraging ESP, our open-source platform for agile heterogeneous SoC design, we demonstrate FPGA prototypes of various SoC designs, featuring the NVIDIA Deep Learning Accelerator and the Ariane RISC-V 64-bit processor core. [ABSTRACT FROM AUTHOR]

Modernising the way upper-limb prosthetic sockets are made has seen limited progress. The casting techniques that are employed in clinics today resemble those developed over 50 years ago and there is still a heavy reliance on manual labour. Modern manufacturing methods such as 3D scanning and printing are often presented as ready-to-use solutions for producing low-cost functional devices, with public perceptions being largely shaped by the superficial media representation and advertising. The promise is that modern socket manufacturing methods can improve patient satisfaction, decrease manufacturing times and reduce the workload in the clinic. However, the perception in the clinical community is that total conversion to digital methods in a clinical environment is not straightforward. Anecdotally, there is currently a disconnect between those developing technology to produce prosthetic devices and the actual needs of clinicians and people with limb difference. In this paper, we demonstrate strengths and drawbacks of a fully digitised, low-cost trans-radial diagnostic socket making process, informed by clinical principles. We present volunteer feedback on the digitally created sockets and provide expert commentary on the use of digital tools in upper-limb socket manufacturing. We show that it is possible to utilise 3D scanning and printing, but only if the process is informed by expert knowledge. We bring examples to demonstrate how and why the process may go wrong. Finally, we provide discussion on why progress in modernising the manufacturing of upper-limb sockets has been slow yet it is still too early to rule out digital methods. [ABSTRACT FROM AUTHOR]

This work studies the design of MET-LDPC code ensembles at low code rates with good threshold performances and exponentially few small weight codewords. There was a notable study on the condition, so called the ‘t-value condition’, for exponentially few small weight codewords. Meanwhile, it was shown that by introducing degree-one variable nodes, the threshold performances of MET-LDPC code ensembles of low rates can be significantly improved. However, the degree-one variable nodes may result in small weight codewords and thus must be carefully introduced to MET-LDPC code ensembles. Despite the importance, the existing t-value condition was developed only for MET-LDPC code ensembles without degree-one variable nodes. This work extends the t-value condition to MET-LDPC code ensembles with degree-one variable nodes, which includes the existing work as a special case. The extended t-value condition provides useful insights into the contributions of degree-one variable nodes to the distribution of small weight codewords. Thus, the results of this work allow us to design MET-LDPC code ensembles of low rates with both good threshold performances and exponentially few small weight codewords. In addition, it will be demonstrated that MET-LDPC codes at finite lengths based on the designed code ensembles have good error-rate performances both in the waterfall and low-error-rate regions. [ABSTRACT FROM AUTHOR]

Amputees are prone to experiencing discomfort when wearing their prosthetic devices. As the amputee population grows this becomes a more prevalent and pressing concern. There is a need for new prosthetic technologies to construct more comfortable and well-fitted liners and sockets. One of the well-recognized impediments to the development of new prosthetic technology is the lack of practical inner socket sensors to monitor the inner socket environment (ISE), or the region between the residual limb and the socket. Here we present a capacitive pressure sensor fabricated through a simple, and scalable sewing process using commercially available conductive yarns and textile materials. This fully-textile sensor provides a soft, flexible, and comfortable sensing system for monitoring the ISE. We provide details of our low-power sensor system capable of high-speed data collection from up to four sensor arrays. Additionally, we demonstrate two custom set-ups to test and validate the textile-based sensors in a simulated prosthetic environment. Finally, we utilize the textile-based sensors to study the ISE of a bilateral transtibial amputee. Results indicate that the textile-based sensors provide a promising potential for seamlessly monitoring the ISE. [ABSTRACT FROM AUTHOR]

The current state of quantum device maturity proposes the use of removable, reusable interconnection means between such device and their classical microelectronic measurement system. One such means is a land grid array (LGA) socket, used pervasively in microelectronics but relatively untested at cryogenic temperatures necessary for most quantum technologies. This article investigates two distinct commercially available LGA socket technologies with respect to contact resistance performance under cryogenic temperature measurement conditions. Test methodologies were successfully developed for both sockets, demonstrating predictable and repeatable contact resistance values during multiple excursions down to 1.5 K and a single excursion to 10 mK. The experimental data show that contact resistance of individual interconnection sites decreased from 30 to 40 mΩ at room temperature to 14-17 mΩ at 1.5 K and to 6–8 mΩ at 10 mK, thus supporting their reliable use in cryogenic measurement applications. Theoretical calculations based on the construction of the microspring socket validated that measured values behaved in a manner that was consistent with temperature-dependent changes in resistivity of the metals comprising the socket interconnection. Spring deflection allowances compensated for any temperature-driven movement of components within the assembly, thus enabling predictable resistance behavior. Regarding the elastomer socket, the high coefficient of thermal expansion (CTE) of the elastomer bulk material induced large variations in socket compression across the temperature range investigated. Sufficient compression to provide consistent contact resistance values at cryogenic temperatures imposed the need for very high compression at room temperature, which may place into question the longer term integrity of this solution. Nevertheless, a preliminary investigation (five cryogenic cycles and subsequent construction analysis) did not reveal any degradation in either socket type. [ABSTRACT FROM AUTHOR]

This article presents a multi-agent control architecture and an online optimization method based on a dynamic average consensus to coordinate the power consumption of a large population of thermostatically controlled loads (TCLs). Our objective is to penalize peaks of power demand, smooth the load profile, and enable demand-side management. The proposed architecture and methods exploit only local measurements of power consumption via smart power sockets (SPSs) with no access to their internal temperature. No centralized aggregator of information is exploited, and agents preserve their privacy by cooperating anonymously only through consensus-based distributed estimation. The interactions among devices occur through an unstructured peer-to-peer (P2P) network over the Internet. Methods for parameter identification, state estimation, and mixed logical modeling of TCLs and SPSs are included. The architecture is designed from a multi-agent and plug-and-play perspective, in which existing household appliances can interact with each other in an urban environment. Finally, a novel low-cost testbed is proposed along with numerical tests and experimental validation. [ABSTRACT FROM AUTHOR]

Patient preference of lower limb prosthesis behavior informally guides clinical decision making, and may become increasingly important for tuning new robotic prostheses. However, the processes for quantifying preference are still being developed, and the strengths and weaknesses of preference are not adequately understood. The present study sought to characterize the reliability (consistency) of patient preference of alignment during level-ground walking, and determine the patient-preferred ankle angle for ascent and descent of a 10° ramp, with implications for the design and control of robotic prostheses. Seven subjects with transtibial amputation walked over level ground, and ascended and descended a 10° ramp on a semi-active prosthetic ankle capable of unweighted repositioning in dorsiflexion and plantarflexion. Preferred ankle angle was measured with an adaptive forced-choice psychophysics paradigm, in which subjects walked on a randomized static ankle angle and reported whether they would prefer the ankle to be dorsiflexed or plantarflexed. Subjects had reliable preferences for alignment during level-ground walking, with deviations of 1.5° from preference resulting in an 84% response rate preferring changes toward the preference. Relative to level walking, subjects preferred 7.8° (SD: 4.8°) of dorsiflexion during ramp ascent, and 5.3° (SD: 3.8°) plantarflexion during ramp descent. As the ankle angle better matched the ramp angle, socket pressures and tibial progression (shank pitch) both more closely mirrored those during level walking. These findings provide baseline behaviors for prosthetic ankles capable of adapting to slopes based on patient preference, and provide strong evidence that people with transtibial amputation can finely perceive ankle alignment. [ABSTRACT FROM AUTHOR]

The vertical stability coil will be used in China Fusion Engineering Test Reactor (CFETR) to improve its control capability on plasma. In view of the severe operation environment and high reliable requirement, it is a challenge for the coil to keep reliability during the whole lifetime, considering the prominent advantages of induction brazing, which is proposed for the coil joint connection. According to the electromagnetic-thermal coupling theory, the induction brazing simulation is carried out under different induction coil parameters. And a set of relatively reasonable induction coil parameter is obtained based on the average temperature and standard deviation of copper sample. In order to verify the brazing performance of the determined induction coil, the brazing experiment is launched with different joint structures and the brazing inspection is performed subsequently. Although it seems some joint design have the advantage of minimizing the damage on the outer magnesium oxide insulation layer, while they fail to satisfy the strength requirement. Based on the lessons, a new joint with thin external sleeve is designed and a series of performance tests are employed. It indicates that there is no large temperature gradient in the joint radial direction and the joint strength is prominently improved. [ABSTRACT FROM AUTHOR]

The loss of somatosensory feedback after transfemoral amputation imposes a serious challenge in achieving postural stability. In the recent past, weight shifting exercises with fixed ankle joint have been reported useful in boosting the limit of stability (LOS) only in the sound limb; the LOS on the prosthetic limb did not improve. A fixed ankle joint restricts movement in the anterior-posterior direction at the ankle level. Thus, it may suppress the ability to move forward LOS despite awareness of center of pressure (COP) due to vibrotactile feedback. Therefore, it could have limited the improvement in the LOS of a prosthetic limb in previous studies. This article investigates this hypothesis by evaluating the effect of vibrotactile feedback in the LOS of transfemoral amputees with fixed as well as movable ankle joints. This evaluation is done during weight shifting exercises. Firstly, we developed an in-house COP guided vibrotactile sensory feedback system. Next, we recruited five transfemoral amputees to perform a weight-shifting exercise with a) fixed ankle joint (single-axis cushion heel (SACH) foot) and b) movable ankle joint (single-axis foot). Finally, we analyzed the recorded center of pressure trajectory signals for the limit of stability. The findings of repeated measures ANOVA showed a marginally significant interaction ($\text{F}_{{(\text {1, 4})}}= {5.7}$ , $\text {p}={0.07}$ , $\eta \text {p}^{{2}}= {0.591}$) between ankle joint and feedback conditions during backward shifting in weight shifting exercise. Further analysis showed that during the backward shifting fixed ankle joint did not improve in the presence of vibrotactile feedback, while a marginally significant ($\text {p}={0.14}$) improved LOS was observed in the movable ankle joint with feedback. The findings conclude that the vibrotactile feedback is more effective in transfemoral amputees with movable ankle joint compared with fixed ankle joint. [ABSTRACT FROM AUTHOR]