Hierarchical Scheduling for Real-Time Periodic Tasks in Symmetric Multiprocessing

In this paper, we present a new hierarchical scheduling framework for periodic tasks in symmetric multiprocessor (SMP) platforms. Partitioned and global scheduling are the two main approaches used by SMP based systems where global scheduling is recommended for overall performance and partitioned scheduling is recommended for hard real-time performance. Our approach combines both the global and partitioned approaches of traditional SMP-based schedulers to provide hard real-time performance guarantees for critical tasks and improved response times for soft real-time tasks. Implemented as part of VxWorks, the results are confirmed using a real-time benchmark application, where response times were improved for soft real-time tasks while still providing hard real-time performance

Selecting Evaluation Indices for Cleaner Production of Plantation Logging in Southern China with Fuzzy Clustering Methods

Over the years, China has shown a significant reduction in natural forest resources, while the increasing area of plantations has made greater contributions to the huge demand for wood. In southern China, these new plantations have produced some problems such as environmental hazards of logging operations and the most reasonable use of forest resources. A new management process called »cleaner production« is defined as reducing pollution from its source, increasing the rate of utilization of resources, and preventing the generation of pollutants in the production of services and products. In recent years, cleaner production has been widely applied to industrial processes such as agriculture and other environmental industries. In order to make rational use of plantation resources, to achieve maximum economic efficiency and to reduce or remove the environmental hazards of logging operations, it is necessary to carry out an in-depth study of cleaner production on the process of logging operations. This paper aims to establish an index system for cleaner production evaluation of plantation logging. The fuzzy clustering method was used to initially screen twenty-nine indices. After screening by the fuzzy clustering method, six first-grade indices and twelve second-grade important indices were selected as formal evaluation indices. The six first-grade indices are 1) cutting area design index, 2) logging operation techniques index, 3) ecological environmental impact index, 4) utilization of resource and energy index, 5) sustainable development index, and 6) safety production management and protection index. A maximum and minimum matrix method and a correlation coefficient matrix method were used to establish the similar matrix in the fuzzy clustering method. The screening results were then compared. The comparison shows that out of the twelve second-grade indices, ten are similar and two are different. The results suggest that the fuzzy clustering method is reliable for screening indices

Trehalose analogues: latest insights in properties and biocatalytic production

Trehalose (alpha-d-glucopyranosyl alpha-d-glucopyranoside) is a non-reducing sugar with unique stabilizing properties due to its symmetrical, low energy structure consisting of two 1,1-anomerically bound glucose moieties. Many applications of this beneficial sugar have been reported in the novel food (nutricals), medical, pharmaceutical and cosmetic industries. Trehalose analogues, like lactotrehalose (alpha-d-glucopyranosyl alpha-d-galactopyranoside) or galactotrehalose (alpha-d-galactopyranosyl alpha-d-galactopyranoside), offer similar benefits as trehalose, but show additional features such as prebiotic or low-calorie sweetener due to their resistance against hydrolysis during digestion. Unfortunately, large-scale chemical production processes for trehalose analogues are not readily available at the moment due to the lack of efficient synthesis methods. Most of the procedures reported in literature suffer from low yields, elevated costs and are far from environmentally friendly. "Greener" alternatives found in the biocatalysis field, including galactosidases, trehalose phosphorylases and TreT-type trehalose synthases are suggested as primary candidates for trehalose analogue production instead. Significant progress has been made in the last decade to turn these into highly efficient biocatalysts and to broaden the variety of useful donor and acceptor sugars. In this review, we aim to provide an overview of the latest insights and future perspectives in trehalose analogue chemistry, applications and production pathways with emphasis on biocatalysis

Clock Gating Flip-Flop using Embedded XoR Circuitry

Flip flops/Pulsed latches are one of the main contributors of dynamic power consumption. In this paper, a novel flip-flop (FF) using clock gating circuitry with embedded XOR, GEMFF, is proposed. Using post layout simulation with 45nm technology, GEMFF outperforms prior state-of-the-art flip-flop by 25.1% at 10% data switching activity in terms of power consumption