A Brake-Based Overground Gait Rehabilitation Device for Altering Propulsion Impulse Symmetry

This paper introduces a new device for gait rehabilitation, the gait propulsion trainer (GPT). It consists of two main components (a stationary device and a wearable system) that work together to apply periodic stance-phase resistance as the user walks overground. The stationary device provides the resistance forces via a cable that tethers the user’s pelvis to a magnetic-particle brake. The wearable system detects gait events via foot switches to control the timing of the resistance forces. A hardware verification test confirmed that the GPT functions as intended. We conducted a pilot study in which one healthy adult and one stroke survivor walked with the GPT with increasing resistance levels. As hypothesized, the periodic stance-phase resistance caused the healthy participant to walk asymmetrically, with greatly reduced propulsion impulse symmetry; as GPT resistance increased, the walking speed also decreased, and the propulsion impulse appeared to increase for both legs. In contrast, the stroke participant responded to GPT resistance by walking faster and more symmetrically in terms of both propulsion impulse and step length. Thus, this paper shows promising results of short-term training with the GPT, and more studies will follow to explore its long-term effects on hemiparetic gait.

LLC Converter Based PV Water Pumping System With Enhanced User Safety Approach

In this paper, LLC resonant converter based Photovoltaic (PV) water pumping is proposed. Commercially, the available PV based water pumping system consists of a non-isolated DC-DC converter, which is suitable for low power applications but results in a less safe operating environment for human. In the case of PV based water pumping systems, the safety of humans should be the main concern, as these systems are normally being operated by farmers, their families and it may possible that they are not that much aware of operational hazards. Therefore, this paper attempts to present an LLC converter based PV water pumping system, considering human safety as a major concern. The proposed system is simulated in MATLABenvironment and results shows that proposed system configuration has no adverse impact on system efficiency and it enhances safety for operating personals. Presented results can be further exploited for hardware verification as the future scope of this work.

LLC Converter Based PV Water Pumping System with Enhanced User Safety Approach

In this paper, LLC resonant converter based Photovoltaic (PV) water pumping is proposed. Commercially, the available PV based water pumping system consists of a non-isolated DC-DC converter, which is suitable for low power applications but results in a less safe operating environment for human. In the case of PV based water pumping systems, the safety of humans should be the main concern, as these systems are normally being operated by farmers, their families and it may possible that they are not that much aware of operational hazards. Therefore, this paper attempts to present an LLC converter based PV water pumping system, considering human safety as a major concern. The proposed system is simulated in MATLABenvironment and results shows that proposed system configuration has no adverse impact on system efficiency and it enhances safety for operating personals. Presented results can be further exploited for hardware verification as the future scope of this work.

Chapter 18. Bounded Model Checking

One of the most important industrial applications of SAT is currently Bounded Model Checking (BMC). This technique is typically used for formal hardware verification in the context of Electronic Design Automation. But BMC has successfully been applied to many other domains as well. In practice, BMC is mainly used for falsification, which is concerned with violations of temporal properties. In addition, a considerable part of this chapter discusses complete extensions, including k-induction and interpolation. These extensions also allow to prove properties.

Isla: Integrating Full-Scale ISA Semantics and Axiomatic Concurrency Models

Architecture specifications such as Armv8-A and RISC-V are the ultimate foundation for software verification and the correctness criteria for hardware verification. They should define the allowed sequential and relaxed-memory concurrency behaviour of programs, but hitherto there has been no integration of full-scale instruction-set architecture (ISA) semantics with axiomatic concurrency models, either in mathematics or in tools. These ISA semantics can be surprisingly large and intricate, e.g. 100k+ lines for Armv8-A. In this paper we present a tool, Isla, for computing the allowed behaviours of concurrent litmus tests with respect to full-scale ISA definitions, in Sail, and arbitrary axiomatic relaxed-memory concurrency models, in the Cat language. It is based on a generic symbolic engine for Sail ISA specifications, which should be valuable also for other verification tasks. We equip the tool with a web interface to make it widely accessible, and illustrate and evaluate it for Armv8-A and RISC-V. By using full-scale and authoritative ISA semantics, this lets one evaluate litmus tests using arbitrary user instructions with high confidence. Moreover, because these ISA specifications give detailed and validated definitions of the sequential aspects of systems functionality, as used by hypervisors and operating systems, e.g. instruction fetch, exceptions, and address translation, our tool provides a basis for developing concurrency semantics for these. We demonstrate this for the Armv8-A instruction-fetch model and self-modifying code examples of Simner et al.