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Nowadays, many real-time applications are very complex and as the complexity and the requirements of those systems become more demanding, more hardware processing capacity is necessary. Unfortunately, the correct functioning of real-time systems depends not only on the logically correct response but also on the time when it is produced. General-purpose processor design fails to deliver analyzability due to their nondeterministic behavior caused by the use of cache memories, dynamic branch prediction, speculative execution, and out-of-order pipelines. In this article, we investigate the pipeline performance of Very Long Instruction Word (VLIW) architectures for real-time systems with an in-order pipeline considering Worst- Case Execution Time (WCET) performance. Techniques on obtaining the WCET of VLIW machines are also considered and we make a quantification on how important are hardware techniques such as static branch prediction, predication, and pipeline speed of complex operations such as memory access and multiplication for high-performance real-time systems. The memory hierarchy is out of the scope of this article and we used a classic deterministic structure formed by a direct mapped instruction cache and a data scratchpad memory. A VLIW prototype was implemented in VHDL from scratch considering the HP VLIW ST231 ISA. We also show some compiler insights and we use a representative subset of the Malardalen's WCET benchmarks for validation and performance quantification. [ABSTRACT FROM AUTHOR]

Distributed Real-Time Thread is an important concept for distributed real-time systems. Distributed Threads are schedulable entities with an end-to-end deadline that transpose nodes, carrying their scheduling context. In each node, the thread will be locally scheduled according to a local deadline, which is defined by a deadline partitioning algorithm. Mechanisms for predicting the missing of deadlines are fundamental if corrective actions are incorporated for improving system quality of service. In this work, a mechanism for predicting missing deadlines is proposed and evaluated through simulation. In order to illustrate the main characteristics of the proposed mechanism, experiments will be presented taking into account different scenarios of normal load and overload. Simulations show that the deadline missing prediction mechanism proposed presents good results for improving the overall performance and availability of distributed systems. [ABSTRACT FROM AUTHOR]

There are several methods of laboratory diagnosis of filarids, the most used are the thick smear and the Knott method. Both are quick to perform, have a low cost and allow observing the presence, quantifying and analyzing the morphological characteristics of microfilariae. Knowing the morphological viability of fixed microfilariae is of practical importance, as it allows the transport of samples to a laboratory, facilitates epidemiological studies , and allows the storage of samples for didactic. Thus, the aim of this study was to evaluate the morphological viability of microfilariae fixed in the refrigerated modified knott test using 2% formalin. To perform the modified Knott technique, 10 samples of microfilaremic dogs aged over 6 months were used. To evaluate the morphological viability time of the microfilariae in the modified Knott concentrate, the evaluations were repeated after intervals of 0, 1, 7, 30, 60, 120, 180, 240, and 304 days. In the present study, we did not verify any difference in the morphology of the microfilariae in any of the analyzed intervals from day 0 to 304 days, and it is possible to conclude that the use of 2% formalin in the modified Knott technique allows the microfilariae to be identified in a period of 304 days. days after processing the sample without changes in its morphology., Competing Interests: Conflicts of interests: The authors declare that they have no competing interest.