feedback fuzzy-dvs scheduling of control tasks

To consider the energy-aware scheduling problem in computer-controlled systems is necessary to improve the control performance, to use the limited computing resource sufficiently, and to reduce the energy consumption to extend the lifetime of the whole system. In this paper, the scheduling problem of multiple control tasks is discussed based on an adjustable voltage processor. A feedback fuzzy-DVS (dynamic voltage scaling) scheduling architecture is presented by applying technologies of the feedback control and the fuzzy DVS. The simulation results show that, by using the actual utilization as the feedback information to adjust the supply voltage of processor dynamically, the high CPU utilization can be implemented under the precondition of guaranteeing the control performance, whilst the low energy consumption can be achieved as well. The proposed method can be applied to the design in computer-controlled systems based on an adjustable voltage processor.

The influence of nitrogen clustering effect on optical transitions in GaInNAs/GaAs quantum wells

Photoluminescence (PL) spectra of GaInNAs/GaAs multiple quantum wells and GaInNAs epilayers grown on GaAs substrate show an apparent "S-shape" temperature-dependence of the of dominant luminescence peak. At low temperature and weak excitation conditions, a PL peak related to nitrogen cluster-induced bound states can be well resolved in the PL spectra. It displays a remarkable red shift of up to 60 meV and is thermally quenched below 100 K with increasing temperature, being attributed to N-cluster induced bound states. The indium incorporation exhibits significant effect on the cluster formation. The rapid thermal annealing treatment at 750 C can essentially remove the bound states-induced peak.

一种基于动态自适应数据窗口的模糊k-均值聚类缺失数据估算算法

完整性是数据质量的一个重要维度,由于数据本身固有的不确定性、采集的随机性及不准确性,导致现实应用中产生了大量具有如下特点的数据集:1)数据规模庞大;2)数据往往是不完整、不准确的.因此将大规模数据集分段到不同的数据窗口中处理是数据处理的重要方法,但缺失数据估算的相关研究大都忽视了数据集的特点和窗口的应用,而且回定大小的数据窗17容易造成算法的准确性和性能受窗口大小及窗口内数据值分布的影响.假设数据满足一定的领域相关的约束,首先提出了一种新的基于时间的动态自适应数据窗口检测算法,并基于此窗口提出了一种改进的模糊k-均值聚类算法来进行不完整数据的缺失数据估算.实验表明较之其他算法,不仅能更适应数据集的特点,具有较好的性能,而且能够保证准确性.

a fuzzy-based method for evaluating the trustworthiness of software processes

University of Paderborn; Fraunhofer Inst. Exp. Softw. Eng. (IESE); Chinese Academy of Science (ISCAS)