Invertible condition of quantum Fisher information matrix for a mixed qubit

Estimating multiparamter simultaneously as precise as possible is an important goal of quantum metrolo- gy. As a first step to this end, here we give a condition determining whether two arbitrary parameters can be estimated simultaneously for a qubit in the mixed state. An application of this condition is shown.Comment: The European Physical Journal D 201

i2MapReduce: Incremental MapReduce for Mining Evolving Big Data

As new data and updates are constantly arriving, the results of data mining applications become stale and obsolete over time. Incremental processing is a promising approach to refreshing mining results. It utilizes previously saved states to avoid the expense of re-computation from scratch. In this paper, we propose i2MapReduce, a novel incremental processing extension to MapReduce, the most widely used framework for mining big data. Compared with the state-of-the-art work on Incoop, i2MapReduce (i) performs key-value pair level incremental processing rather than task level re-computation, (ii) supports not only one-step computation but also more sophisticated iterative computation, which is widely used in data mining applications, and (iii) incorporates a set of novel techniques to reduce I/O overhead for accessing preserved fine-grain computation states. We evaluate i2MapReduce using a one-step algorithm and three iterative algorithms with diverse computation characteristics. Experimental results on Amazon EC2 show significant performance improvements of i2MapReduce compared to both plain and iterative MapReduce performing re-computation

Literature Review: The Green Economy, Clean Energy Policy and Employment

AbstractThe relationship between the green economy and employment is never as simple as it appears. This article analyses this relationship based on studies of clean energy policies in different countries. Through literature studies, we found that the green economy has positive effects on employment in both developing and developed countries, while the results can alter according to the type of measurement adopted. However, the Green economy can also have negative effects in some countries like Spain. Moreover, it may shape the labor market in another way if policy influence is taken into consideration. Finally, we must realize that there are some problems with the current researches in this area, such as the lack of studies on different countries and energy types, inadequate theoretical support, limited analysis of such relationship, and so on. We suggest that scholars should focus on mechanisms whereby this relationship is influenced and policies to regulate such relationships in further researches