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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Vehicle safety can be improved by tire pressure monitoring with a wireless sensor system. Since a battery-powered wireless sensor system for tire pressure information is limited by the life of the battery, energy harvesting technology is applied. In order to develop an energy harvester based on a piezoelectric material for the tires, modeling of tire behavior and the energy harvester, and the validation of the modeling were performed. The structural behavior of a tire was numerically modeled and verified by comparing the simulation results with experimental data. In order to compare the generated voltages between the modeling and the experiment, comparisons of the root-mean-square voltage values for various velocities and loads, the distortion factor using the root-mean-square value of the wave form, and the crest factor for verifying the efficiency of the peak value of the wave form were conducted. The results showed that the differences are on average 10% for the loads between 300 and 700 kgf and velocities between 20 and 60 km/h (430 r/min). For the improvement of the energy harvester's performance, the thickness of substrate was controlled and the generated voltage was increased. If a sensor for measuring radius is applicable to the tire, the strain on the tire can be collected, and thus the loads applied to the tire can be estimated. With a wireless sensor system for measuring radius driven by energy harvesting, we can be one step closer to the embodiment of an intelligent tire.

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Hemostatic agents with diverse forms and materials are necessitated to control excessive bleeding to improve surgical site visibility during operation. The adequate use of hemostatic agents dramatically reduces the chance of dehydration, absence of oxygen, and, in severe cases, death. Polysaccharide-based hemostatic agents are widely used as they are safe for the human body. Among diverse polysaccharides, starch has exhibited a high swelling ability, but its powder formulation is limited during incompressible bleeding. Herein, starch was blended with silk protein and crosslinked using glycerol to improve structural integrity. The silk/starch solution was lyophilized to be a sponge with interconnected pores, which is beneficial to blood coagulation by increased swelling ratio and underwater retentivity to absorb blood plasma. The surface contact between the blood component and the sponge initiates clotting by intrinsic pathway activation and platelet activation without the hemolytic effect or cytotoxicity. The clinical effectiveness of the sponges as topical hemostatic agents was confirmed by animal bleeding model tests.