A wideband printed dual-antenna system for mobile terminals is presented. The dual-antenna, consisted of two symmetric antenna elements and a neutralization line (NL), is printed on a printed circuit board. The antenna element is an F-like monopole with a grounded branch. The working mechanism of the dual-antenna is analyzed based on the -parameters and the surface current distributions. A prototype shows the measured 10-dB impedance bandwidth is 1.09 GHz (1.67-2.76 GHz) and the measured mutual coupling is lower than 15 dB at the 1.7-2.76-GHz bands. It covers the GSM1800, GSM1900, UMTS, LTE2300, LTE2500, and 2.4-GHz WLAN bands. The radiation patterns are measured, and the diversity performance is evaluated.Index Terms-Broadband decoupling, grounded branch, multiple-input-multiple-output (MIMO), multiantenna, neutralization line.

Link prediction is the problem of predicting the location of either unknown or fake links from uncertain structural information of a network. Link prediction algorithms are useful in gaining insight into different network structures from partial observations of exemplars. However, existing link prediction algorithms only focus on regular complex networks and are overly dependent on either the closed triangular structure of networks or the so-called preferential attachment phenomenon. The performance of these algorithms on highly sparse or treelike networks is poor. In this letter, we proposed a method that is based on the network heterogeneity. We test our algorithms for three real large sparse networks: a metropolitan water distribution network, a Twitter network, and a sexual contact network. We find that our method is effective and performs better than traditional algorithms, especially for the Twitter network. We further argue that heterogeneity is the most obvious defining pattern for complex networks, while other statistical properties failed to be predicted. Moreover, preferential attachment based link prediction performed poorly and hence we infer that preferential attachment is not a plausible model for the genesis of many networks. We also suggest that heterogeneity is an important mechanism for online information propagation.

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Lack of access to basic education leads to diminished individual and national capabilities, therewith furthering cycles of poverty. An equitable education system meeting basic learning needs represents not only a human right, but also a means for reducing poverty, promoting productivity, and sustaining development. The Government of China -the most populous developing nation, the majority of whose citizens live in rural areas -has been committed to universalizing nine-year compulsory education among school-aged children and eliminating illiteracy among youths and adults aged 15-45. This study examines lessons learned from China's efforts in these areas. It also reports on current challenges and trends in a new national initiative for achieving high-quality universal basic education by the year 2007.

Recent literature has turned to the brain gain effect, instead of the brain drain effect, that emigration may bring to a source country. This paper, however, suggests brain drain remains a likely outcome. Suppose that foreign language skill affects an individual productivity when working abroad. A brain drain may occur when the (exogenously or endogenously determined) probability of immigration is large. We also consider the case that the probability of immigration is determined by a signal, and provide a condition under which the individual will under-invest in education, which results in a brain drain for the source country. Copyright Springer-Verlag 2005F22, O15, J61, Brain gain, brain drain, probability of immigration,