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Makio Kurashige Kazutoshi Ishida Tomoe Takanokura Yasuyuki Ohyagi Masachika Watanabe 《Journal of the Society for Information Display》2011,19(9):631-638
Abstract— While laser projection has many advantages, there is a problem with speckle patterns generated as a result of interference of the laser beam and results in bad effects to observers. In 2010, a variable speckle generator, which produces an angular shift of incident light to the screen and generates variable speckle patterns, was suggested. In this study, the performance of a variable speckle generator by using a volume phase holographic beam shaper and scanning mirror was investigated in detail by evaluating both the objective and subjective speckle contrast. The morphology of the speckle pattern was also investigated when the variable speckle generator was activated. With a scanning VPH beam shaper, the objective speckle was effectively reduced because each point of the VPH beam shaper generated different speckle patterns and coherency among each pattern disappeared by using the scan process. On the other hand, subjective speckle was also dramatically reduced by changing the incident angle on the screen, which resulted in generating variable subjective speckle. It was also shown that the speckle reduction rate by using a variable speckle generator did not depend on the coherent length of a laser by evaluating the normalized speckle contrast against the angular shift on the screen. 相似文献
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Active worms have posed a major security threat to the Internet and many research efforts have focused on them. However, defending against them remains challenging due to their continuous evolution. In this paper, we study a new class of defense-oriented evolved worms, the Varying Scan Rate worm (the VSR worm in short). In order to circumvent detection by existing worm detection schemes, the VSR worm deliberately varies its scan rate according to these schemes’ weaknesses. To counteract the VSR worm, we design a new worm-detection scheme, the attack-target Distribution Entropy-based Dynamic detection scheme (DED detection for short). DED detection utilizes the attack-target distribution and robust statistical feature in conjunction with dynamic decision adaptation to distinguish worm-scan traffic from non-worm-scan traffic. We present a comparatively complete space of detection schemes and conduct extensive performance evaluations on the DED detection scheme compared with other schemes, using real-world Internet traces as background scan traffic. Our data clearly demonstrate the effectiveness of the DED detection scheme in detecting both the VSR worm and the traditional worm. 相似文献
66.
Yanzhao Ma Junghoon KwonZhihong Mao Kunwoo Lee Linlin LiHayoung Chung 《International Journal of Industrial Ergonomics》2011,41(1):19-29
In this study, body segment parameters of Korean adults were estimated using the three-dimensional (3D) body scan data from the SizeKorea database. Mass-inertial parameters and segment dimensions of 40 male subjects and 40 female subjects (18-59 years old) were estimated using a 16-segment model under the assumption that each segment has a constant density distribution after reconstructing the scan data. Therefore, several sets of linear regression functions based on gender, stature, and weight were established, which provided a convenient method for estimating body segment parameters of Korean adults. The obtained mass ratios of body segments were compared with those for Russians reported by Zatsiorsky and Seluyanov (1983) and for those for Chinese and Germans reported by Shan and Bohn (2003), in which the same 16-segment model was used. In addition, the results were compared with the Korean data results reported by
[Jung, 1993] and [Lim, 1994], and Park et al. (1999). These comparisons revealed that Asians have larger head mass ratios and smaller lower limb mass ratios than Caucasians, while the differences in the head mass ratios between males and females from the same ethnic groups were not significant. Females were found to have larger mass ratios for the lower torso and smaller mass ratios for the upper torso, middle torso, upper arm, forearm, foot, and hand, as compared to males from the same ethnic groups. In addition, the data obtained by different researchers were compared, thereby showing high reproducibility of our method.
Relevance to industry
The obtained segment parameters can be used to define digital human models and applied to the fields of ergonomics and biomechanics, such as for workspace design, furniture design, vehicle interior design, and human movement analysis. 相似文献67.
介绍一种用8031(8051)串口,联级新型的共阴极驱动芯片— —MAX7219霓虹灯扫描控制器。着重论述了该芯片的硬件特点、使用方法及软件编制方法, 给出了用该芯片驱动多点霓虹灯变压器的实例。 相似文献
68.
高性能容错处理核心的研究 总被引:2,自引:0,他引:2
本文提出了以三模冗余表决为基础构造容错处理核心的方案。三个CPU模块采取松散同步的形式,只有在发生总线操作时才进行同步表决。在处理核心中采用了两级故障检测机制,以三模表决器作为第一级来保证处理核心有足够高的故障覆盖率;以CPUA模块的自检作为第二级来弥补表决器发现故障延迟的不足,缩短故障的潜伏时间。在表决器的设计中采取了表决器旁路及先编码、后表决的方法。先用编码的方式提取需要表决的数据的特征,然后 相似文献
69.
船舶“超吃水冶引起的船舶搁浅事故呈逐年增多的趋势,对内河离港船舶吃水进行实时测量尤为必要. 针
对内河航道的特点,提出了一种利用单波束声收发分体传感器同步对船舶底部边缘进行扫描测量的方法,研究
了传感器系统构成,并对测量原理进行了理论推导. 设计了比尺为1100 的吃水测量试验系统,利用3 000 t级
小比尺船模按4 种工况进行试验,结果表明,船舶航速对船舶吃水测量值有一定影响,但最大误差仍控制在
11. 4%以内,证明了这种测量方法的可行性. 相似文献
70.
为了提高存储器的边界扫描测试软件的通用性,提出一种基于TCL语言及边界扫描技术的存储器测试脚本设计方案。结合存储器测试理论及边界扫描逻辑簇测试技术,研究基于TCL脚本语言的存储器测试脚本设计方法,用以在进行存储器簇测试时描述存储器自身的读写特性及与其外部边界扫描测试单元的连接关系等,并给出HY6264SRAM静态存储器功能测试的例子。通过测试验证,使用TCL脚本语言与高级语言联合编程能够提高边界扫描测试软件的工作效率。 相似文献