Challenge and Methods of Synchronous Disk I／O

At present, I/O is the performance bottleneck limiting the speed of computer systems. A large number of I/O operations are synchronous read/write operations of only small data blocks. However, reducing the latency of synchronous I/O operation is a non-trivial problem. In this paper, we propose two methods to address this problem. The first method, FastSync, uses a cache disk optimized for write operation via use of a disk-head position prediction algorithm. In this way, disk capacity is traded for synchronous I/O performance. The second method, LND, uses free memory capacity in a network environment as a cache disk for the buffeting of synchronous I/O operation. Data integrity in FastSync is ensured by using a data log on the cache disk, whereas in LND, integrity is ensured by the storage in distributed memory of multiple copies of each data block. Both methods succeed in dramatically increasing the performance of synchronous I/O operation. The performance of LND is limited by the network speed, whereas performance of FastSync is determined mostly by the data block size.     

磁感应热疗联合艾迪对Daudi细胞作用的研究

 为研究磁感应热疗联合艾迪注射液对人淋巴瘤Daudi细胞的作用,首先进行磁性介质对Daudi细胞生物相容性的研究以及磁性介质升温性能的检测,运用CCK-8法测出不同艾迪药物质量浓度对细胞增殖率的影响选出本实验工作浓度,将对数生长期的人淋巴瘤细胞Daudi分别暴露于磁场、艾迪注射液、磁场与艾迪联合作用下,采用流式细胞技术分析各组实验作用下对细胞凋亡、细胞周期的影响。结果表明：本实验选用的不锈钢空心球具有良好的发热效率以及细胞相容性;本研究选用75 mg/mL作为工作浓度;磁感应热疗作用Daudi细胞后,细胞存活率为（78.48±0.95）%,联合艾迪注射液治疗后,细胞存活率为（9.25±2.05）%（P<0.01）;磁感应热疗联合艾迪注射液能够增加细胞凋亡率,而对细胞周期改变不明显。由此可知,磁感应热疗磁性介质应用于淋巴瘤治疗在细胞水平是可行的;磁感应热疗单独使用可以诱导Daudi细胞凋亡,艾迪注射液与其联合应用时能表现出协同抗淋巴瘤细胞作用。     

自动控制系统抗电磁干扰的措施

针对自动控制系统中有关传导干扰的问题,对电磁兼容问题的学科内容进行简单介绍,并对自动控制系统中传导干扰进行了研究和分析,总结和讨论了一些有效抑制系统中传导干扰的措施和方法。