Investigation of the speed-up of a dual microcontroller parallel processing system in the execution of a mathematical operation

An investigation of the performance of a two microcontroller parallel processing system is presented. A twomicrocontroller parallel processing is developed using low end microcontrollers (PIC 16F877). An 8x8 bit multiply operation and a 16x16 bit multiply operation are executed on a single microcontroller and on the proposed dual microcontroller parallel processing system in order to assess the performance of the proposed system. Results presented show poor performance for the 8x8 bit multiply with an average speed up factor of 0.82 This is due to the time required to transfer data around the dual microcontroller system being significant in comparison to the time required to complete the multiply operation, thus nullifying the potential advantage that might be expected of a dual microcontroller system. The 16x16 multiplier exhibited good performance, with results showing a maximum average speed up factor of 1.7 and an average speed up factor of 1.5. The 16x16 multiplication requires longer time to compute and the data transfer time between microcontrollers whilst still having an impact on the overall computation time is significantly less than for the 8x8 multiplier A formula has been developed to provide an estimate of the possible speed up within a system in relation to the process execution time and the time required to communicate data around the proposed system. The proposed system was developed and tested using the Proteus simulation software

Ecological User Equilibrium in Traffic Management (TM)?

With increasing environmental sustainability awareness significant attention on ecological traffic management (eco-TM) has come into the focus of researchers and practitioners. While different approaches have been applied to reach minimal pollutant production, the classic user equilibrium calculation with the pollutant production as travel costs instead of using travel times remains in the center of attention. However, the validity of such a direct transformation to find a user equilibrium is questionable. In this paper, a simplified analytical approach to examine the above aforementioned validity has been carried out, followed by a simulation approach to verify the results of the analytical approach. The result shows that the pollutant production function violates the usual assumption of a monotonous function (typically, emission has a minimum at travel speeds around 60 km/h). It also indicates that the respective algorithms to compute the user equilibrium must deal with the fact, that the equilibrium solution is not unique and is dependent on the initial solution. This means that substantial modifications to the algorithms that compute the user equilibrium have to be discussed since they do not work as intended when pollutant production is used as travel costs, especially in a transportation system with mixed speeds that cover a range around the minimum emission speed

Mihai Gheorghiade, MD-Life and Concepts

How do you capture an idea, shape it, and then bring it into the world? Of his many talents, this ability was a fundamental characteristic of Mihai Gheorghiade. A quick glance through PubMed confirms his prodigious output, likely to overwhelm any novice or even expert scholar. His contribution to heart failure, especially acute heart failure (AHF), is profound, He authored several major concepts in acute heart failure, disseminated further by his students. Most concepts remained indelibly linked to his name: Digoxin trials research(1–3), AHFS (acute heart failure syndromes) definition(4), hemodynamic congestion(5), hospitalized heart failure (HHF) (6), the vulnerable phase(7,8), neutral hemodynamic agents(9), registries(10–12) and pre-trial registries(13), the “6-axis model”(14) and then the “8-axis model”(15). His work shaped the field of AHF