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Purpose:To compare computed tomography (CT) images and bronchoscopic findings of local tumor recurrence at the bronchial stump site in post-operative non-small cell lung cancer (NSCLC) patients. Materials and Methods: A retrospective study was conducted to review the CT images of 9 lung cancer cases that recurred at the bronchial stump site on 576 resected primary non-small cell lung cancers over a 9-year period. The CT images of the bronchial stump site recurrence were classified as: bronchial wall thickening, nodular or endobronchial polypoid lesion, multiplicity, and enhancement patterns. We classified the bronchoscopic findings based on the revised classification by the Japan Lung Cancer Society. Results: The histologic types of the 9 cases of lung cancer that recurred, included 7 squamous cell carcinomas, 1 adenocarcinoma, and 1 adenoid cystic carcinoma. The CT findings included bronchial wall thickening with nodules (n = 6) and endobronchial polypoid nodules (n = 3) with heterogeneous enhancement. The CT findings were further classified as nodular infiltrating type (n = 5), polypoid type (n = 3) and superficial infiltrating type (n = 1) on bronchoscopy. Conclusion: Both a bronchoscopy and CT can be used as a complementary or alternative tool in evaluating bronchial stump site recurrences.

Abstract-Due to the recent advances in PhageChange Memory (PCM) technologies, a new memory hierarchy of computer systems with PCM is expected to appear. In this paper, we present a new page replacement policy that adopts PCM as a high speed swap device. As PCM has limited write endurance, our goal is to minimize the amount of data written to PCM. To do so, we defer the eviction of dirty pages in proportion to their dirtiness. However, excessive preservation of dirty pages in memory may deteriorate the page fault rate, especially when the memory capacity is not enough to accommodate full working-set pages. Thus, our policy monitors the current working-set size of the system, and controls the deferring level of dirty pages not to degrade the system performances. Simulation experiments show that the proposed policy reduces the write traffic to PCM by 160% without performance degradations.

Recently, NVM (non-volatile memory) has advanced as a fast storage medium, and traditional memory management systems designed for HDD storage should be reconsidered. In this article, we revisit the page sizing problem in NVM storage, specially focusing on virtualized systems. The page sizing problem has not caught attention in traditional systems because of the two reasons. First, the memory performance is not sensitive to the page size when HDD is adopted as storage. We show that this is not the case in NVM storage by analyzing the TLB miss rate and the page fault rate, which have trade-off relations with respect to the page size. Second, changing the page size in traditional systems is not easy as it accompanies significant overhead. However, due to the widespread adoption of virtualized systems, the page sizing problem becomes feasible for virtual machines, which are generated for executing specific workloads with fixed hardware resources. In this article, we design a page size model that accurately estimates the TLB miss rate and the page fault rate for NVM storage. We then present a method that has the ability of estimating the memory access time as the page size is varied, which can guide a suitable page size for given environments. By considering workload characteristics with given memory and storage resources, we show that the memory performance of virtualized systems can be improved by 38.4% when our model is adopted.