Vibrational spectra and structure of ZrF4-FeF3-PbF2-YF3 fluoride glasses

Results of the investigation of infrared and Raman spectra in heavy metal fluoride glasses based on the ZrF4-FeF3-PbF2-YF3 system are presented. Infrared and Raman bands in the spectra of these glasses are discussed. The coordination environments of both Zr4+ and Fe3+ ions have been extracted from the vibrational modes. Α structural model for these glasses is proposed. It is composed of the basic network formers ZrF7 polyhedra and FeF6 octahedra, which are randomly linked by corners and/or edges to construct a disordered three-dimensional network, whereas the Pb2+ and Y3+ ions are assumed to play the role of network modifier and stabilizer, respectively

Characterizing and Subsetting Big Data Workloads

Big data benchmark suites must include a diversity of data and workloads to be useful in fairly evaluating big data systems and architectures. However, using truly comprehensive benchmarks poses great challenges for the architecture community. First, we need to thoroughly understand the behaviors of a variety of workloads. Second, our usual simulation-based research methods become prohibitively expensive for big data. As big data is an emerging field, more and more software stacks are being proposed to facilitate the development of big data applications, which aggravates hese challenges. In this paper, we first use Principle Component Analysis (PCA) to identify the most important characteristics from 45 metrics to characterize big data workloads from BigDataBench, a comprehensive big data benchmark suite. Second, we apply a clustering technique to the principle components obtained from the PCA to investigate the similarity among big data workloads, and we verify the importance of including different software stacks for big data benchmarking. Third, we select seven representative big data workloads by removing redundant ones and release the BigDataBench simulation version, which is publicly available from http://prof.ict.ac.cn/BigDataBench/simulatorversion/.Comment: 11 pages, 6 figures, 2014 IEEE International Symposium on Workload Characterizatio