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Following the trend of increasing autonomy in cyber-physical systems, parallel embedded architectures have enabled devices to better handle the large streams of data and intensive computation required by such autonomous systems. However, while the explosion of highly-parallel platforms has seen a proportional growth in the number of applications/devices that utilize these platforms, the embedded systems community’s understanding of how to build time-predictable, safety-critical systems with parallel platforms has not kept pace. As a well-motivated but challenging parallel scheduling model, gang scheduling requires all parallel threads of each parallel task to simultaneously execute in unison, which is in contrast to traditional, multi-threaded parallel scheduling, where a parallel task may spawn multiple threads, and each thread will be scheduled independently of other threads of the same task. While increasing research efforts on hard real-time (HRT) gang scheduling have recently been seen, the problem of gang scheduling in the context of soft real-time (SRT) systems, where provably bounded deadline tardiness can be tolerated, has hardly been studied yet. In this article, we derive and prove the first tardiness bounds for sporadic gang task systems under preemptive GEDF scheduling. A total utilization bound for SRT-schedulability is required for ensuring such tardiness bounds but it is shown to be tight with respect to the platform capacity and maximum parallelism-induced idleness. Furthermore, we also empirically evaluate the effects of different degrees of task parallelism upon the SRT-schedulability.

This paper analyzes the necessity of establishing the occupational injury security system for new forms of business and summarizes the pilot areas of the current occupational injury security sy stem, and then analyzes the problems existing in the current occupational injury security for new forms of business, including the difficulty in identifying labor relations and the mismatch between supply and demand of occupational injury security. Finally, the specific conception of occupational injury protection system for employees in the new form of business is put forward, including open insured objects, appropriate payment base, flexible identification of occupational injury, etc.

For safety-critical| computer systems, time-predictability and performance are usually required simultaneously in I/O virtualization. However, both requirements are challenging to achieve due to complex I/O access path and resource management at system level and lack of support from preemptive scheduling at I/O hardware level. In this paper, we propose a new framework, I/O-GUARD, which reconstructs the system architecture of I/O virtualization, bringing a dedicated hardware hypervisor to handle resource management throughout the system. The hypervisor improves system real-time performance by enabling preemptive scheduling in I/O virtualization with both analytical and experimental real-time guarantees. Specifically, I/O-GUARD is a First-of-Its-Kind framework for multi-/many-core I/O virtualization.

A spectral-domain optical coherence tomography (SD-OCT) system with 1555nm center wavelength is tested for stability and accuracy from the micron level to the sub-micron level. The energy centrobaric correction method is used to extract the sub-axial-resolution information as the optical path difference, i.e., the topographic height. We compared the used algorithm with the widely applied phase slope method. The stability of a point scanning OCT system in Michelson style is experimentally compared with that of a system in Fizeau style. Several simple and complicated samples are measured and compared. Finally, we compare the topographic performance of the OCT system with a commercial confocal microscope and white-light interferometer (WLI).