Abstract-In content-oriented networking, content files are typically cached in network nodes, and hence how to cache content files is crucial for the efficient content delivery and cache storage utilization. In this paper, we propose a content caching scheme, WAVE, in which the number of chunks to be cached is adjusted based on the popularity of the content. In WAVE, an upstream node recommends the number of chunks to be cached at its downstream node, which is exponentially increased as the request count increases. Simulation results reveal that the average hop count of content delivery of WAVE is lower than other schemes, and the inter-ISP traffic volume of WAVE is the second lowest (CDN is the lowest). Also, WAVE achieves higher cache hit ratio and fewer frequent cache replacements than other on-demand caching strategies.

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Although vertebral artery groove and foramen violations were relatively common on postoperative CT scans, none were detected intraoperatively or on postoperative radiographs. Most alarmingly, 1 vertebral artery injury was undetected intraoperatively. Since a vertebral injury can be potentially catastrophic, this study emphasizes the inherent dangers associated with placement of C1 and C2 screws and underscores the importance of careful postoperative evaluation and surgical technique when inserting these screws.

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The ferroelectricity in ultrathin HfO2 offers a viable alternative to ferroelectric memory. A reliable switching behavior is required for commercial applications; however, many intriguing features of this material have not been resolved. Herein, we report an increase in the remnant polarization after electric field cycling, known as the “wake-up” effect, in terms of the change in the polarization-switching dynamics of a Si-doped HfO2 thin film. Compared with a pristine specimen, the Si-doped HfO2 thin film exhibited a partial increase in polarization after a finite number of ferroelectric switching behaviors. The polarization-switching behavior was analyzed using the nucleation-limited switching model characterized by a Lorentzian distribution of logarithmic domain-switching times. The polarization switching was simulated using the Monte Carlo method with respect to the effect of defects. Comparing the experimental results with the simulations revealed that the wake-up effect in the HfO2 thin film is accompanied by the suppression of disorder.