Phase-change random access memory (PRAM) is considered as one of the most promising candidates for future memories because of its good scalability and cost-effectiveness [1]. Besides implementations with standard interfaces like NOR flash or LPDDR2-NVM, application-oriented approaches using PRAM as main-memory or storage-class memory have been researched [2][3]. These studies suggest that noticeable merits can be achieved by using PRAM in improving power consumption, system cost, etc. However, relatively low chip density and insufficient write bandwidth of PRAMs are obstacles to better system performance. In this paper, we present an 8Gb PRAM with 40MB/s write bandwidth featuring 8Mb sub-array core architecture with 20nm diode-switched PRAM cells [4]. When an external high voltage is applied, the write bandwidth can be extended as high as 133MB/s.

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[1] The radiative effects of cirrus clouds are evaluated based on observations extending over a period of six years (2000 -2005) from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Clouds and the Earth's Radiant Energy System (CERES) over the Tropics (25°S-25°N). The cloud radiative effect (CRE) shows a positive sign for optically thin cirrus (total-column cloud optical depth: t < 10) and a negative sign for thicker clouds (t ! 10), regardless of the region and season. Since a considerable portion of tropical ice clouds consists in thin cirrus clouds (>60%), their net effective CRE (net CRE Â cloud amount) is roughly twice as strong as that of thicker clouds; the modulation of the net radiative flux by variations in thin cirrus (particularly with 1 t < 9) dominates-up to 15 W m À2-that by thicker clouds. These results suggest that thin cirrus has a significant effect on the tropical energy balance.

Just as the iris of human eye controls the light influx (iris effect), tropical anvil cirrus clouds may regulate the Earth's surface warming by controlling outgoing longwave radiation. This study examines this possible effect with monthly satellite observations such as Tropical Rainfall Measuring Mission (TRMM) precipitation, Moderate Resolution Imaging Spectroradiometer cirrus fraction, and Clouds and the Earth's Radiant Energy System top‐of‐the‐atmosphere radiative fluxes averaged over different tropical domains from March 2000 to October 2014. To confirm that high‐level cirrus is relevant to this study, Cloud‐Aerosol Lidar with Orthogonal Polarization high cloud observations were also analyzed from June 2006 to December 2015. Our analysis revealed that the increase in sea surface temperature in the tropical western Pacific tends to concentrate convective cloud systems. This concentration effect very likely induces the significant reduction of both stratiform rain rate and cirrus fraction, without appreciable change in the convective rain rate. This reduction of stratiform rain rate and cirrus fraction cannot be found over its subregion or the tropical eastern Pacific, where the concentration effect of anvil cirrus is weak. Consistently, over the tropical western Pacific, the higher ratio of convective rain rate to total rain rate (i.e., precipitation efficiency) significantly correlates with warmer sea surface temperature and lower cirrus fraction. The reduced cirrus eventually increased outgoing longwave radiation to a greater degree than absorbed solar radiation. Finally, the negative relationship between precipitation efficiency and cirrus fraction tends to correspond to a low global equilibrium climate sensitivity in the models in the Coupled Model Intercomparison Project Phase 5. This suggests that tropical anvil cirrus clouds exert a negative climate feedback in strong association with precipitation efficiency.