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Readers of Chinese braille need an efficient system of sound-generated braille and an opportunity to gain access to the character structure. This article presents a brief history of the Chinese braille system and the Chinese character structure, discusses the present Chinese sound-generated braille system and its limitations, and proposes some refinements of the present system and some techniques for instruction.

This article was published in the Transactions of the Institute of Metal Finishing [© W.S. Maney & Son Ltd.] and the definitive version is available at: http://dx.doi.org/10.1179/0020296715Z.000000000227 ; Electroplated zinc finishes have been associated with the electronics industry for many years as a result of their excellent corrosion resistance and relatively low cost. They are normally applied onto ferrous products to provide corrosion protection in a range of different environments. However, the formation of spontaneously grown whiskers on zinc-electroplated components, which are capable of resulting in electrical shorting or other damaging effects, can be highly problematic for the reliability of long life electrical and electronic equipment. The growth of zinc whiskers has been identified as the cause of some electrical and electronic failures in telecommunications and aerospace-based applications, with consequences ranging from mild inconvenience to complete system failures. Investigators have been striving to address the problems induced by whisker growth since 1940s. However, most research effort has been focused on tin whiskers, especially following European Union environmental legislation that restricted the use of lead (Pb), which when alloyed with tin (3–10% by weight) provided effective tin whisker mitigation. Compared with tin whisker research, much less attention has been paid to zinc whiskers. A number of mechanisms to explain zinc whisker growth have been proposed, but none of them are widely accepted and some are in conflict with each other. The aim of this paper is to review the available literature in regard to zinc whiskers, to discuss the reported growth mechanisms, to evaluate the effect of deposition parameters and to explore potential mitigation methods. This paper presents a chronologically ordered review of zinc whisker-related studies from 1946 to 2013. Some important early research, which investigated whisker growth in tin and cadmium, as well as zinc, has also been included.

Abstract. The geomagnetic field is subject to possible reversals or excursions of polarity during its temporal evolution. Considering that: (a) in the last 83 million yr the typical average time between one reversal and the next (the so-called chron) is around 400 000 yr, (b) the last reversal occurred around 780 000 yr ago, (c) more excursions (rapid changes in polarity) can occur within the same chron and (d) the geomagnetic field dipole is currently decreasing, a possible imminent geomagnetic reversal or excursion would not be completely unexpected. In that case, such a phenomenon would represent one of the very few natural hazards that are really global. The South Atlantic Anomaly (SAA) is a great depression of the geomagnetic field strength at the Earth's surface, caused by a reverse magnetic flux in the terrestrial outer core. In analogy with critical point phenomena characterized by some cumulative quantity, we fit the surface extent of this anomaly over the last 400 yr with power law or logarithmic functions in reverse time, also decorated by log-periodic oscillations, whose final singularity (a critical point tc) reveals a great change in the near future (2034 ± 3 yr), when the SAA area reaches almost a hemisphere. An interesting aspect that has recently been found is the possible direct connection between the SAA and the global mean sea level (GSL). That the GSL is somehow connected with SAA is also confirmed by the similar result when an analogous critical-like fit is performed over GSL: the corresponding critical point (2033 ± 11 yr) agrees, within the estimated errors, with the value found for the SAA. From this result, we point out the intriguing conjecture that tc would be the time of no return, after which the geomagnetic field could fall into an irreversible process of a global geomagnetic transition that could be a reversal or excursion of polarity.