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The high resolution of digital cameras has made single‐shot, single‐sensor acquisition of light fields feasible, though considerable design effort is still necessary in order to construct the necessary collection of optical elements for particular acquisition scenarios. This paper explores a pipeline for designing, fabricating and utilizing faceted mirror arrays which simplifies this task. The foundation of the pipeline is an interactive tool that automatically optimizes for mirror designs while exposing to the user a set of intuitive parameters for light field quality and manufacturing constraints. We investigate two manufacturing processes for automatic fabrication of the resulting designs: one is based on CNC milling, polishing, and plating of one solid work piece, while the other involves assembly of CNC‐cut mirror facets. We demonstrate results for refocusing in a macro photography scenario. In addition, we observe that traditional photographic parameters take novel roles in the faceted mirror array setup and discuss their influence. 相似文献
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ZnSe宽带隙半导体光发射器件 总被引:1,自引:0,他引:1
ZnSe宽带隙半导体光发射器件是未来全色光显示和高密度光记录用的重要器件。在相继完成材料、掺杂技术,以及器件结构相关的研究工作后,目前正在攻克器件实用化的关键技术——寿命。介绍了ZnSe的p型和n型导电材料的控制技术及其LD和LED的开发进展。 相似文献
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Unaided authentication services provide the flexibility to login without being dependent on any additional device. The power of recording attack resilient unaided authentication services (RARUAS) is undeniable as, in some aspects, they are even capable of offering better security than the biometric based authentication systems. However, high login complexity of these RARUAS makes them far from usable in practice. The adopted information leakage control strategies have often been identified as the primary cause behind such high login complexities. Though recent proposals havemade some significant efforts in designing a usable RARUAS by reducing its login complexity, most of them have failed to achieve the desired usability standard. In this paper, we have introduced a new notion of controlling the information leakage rate. By maintaining a good security standard, the introduced idea helps to reduce the login complexity of our proposed mechanism − named as Textual-Graphical Password-based Mechanism or TGPM, by a significant extent. Along with resisting the recording attack, TGPM also achieves a remarkable property of threat detection. To the best of our knowledge, TGPM is the first RARUAS, which can both prevent and detect the activities of the opportunistic recording attackers who can record the complete login activity of a genuine user for a few login sessions. Our study reveals that TGPM assures much higher session resiliency compared to the existing authentication services, having the same or even higher login complexities. Moreover, TGPM stores the password information in a distributed way and thus restricts the adversaries to learn the complete secret from a single compromised server. A thorough theoretical analysis has been performed to prove the strength of our proposal from both the security and usability perspectives. We have also conducted an experimental study to support the theoretical argument made on the usability standard of TGPM. 相似文献
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Our recent study on a challenge of new materials for next generation's magnetic recording approaching an ultra high areal recording density beyond 1 Tbit/in.2 is overviewed. We proposed novel methods for fabricating high performance magnetic recording heads and media by making the best use of wet (electro- and electroless-deposition) and dry (sputtering) processes. We believe that these results contribute significantly to the progress in magnetic recording and constitute a breakthrough for materializing an unexplored areal recording density beyond 1 Tbit/in.2. 相似文献
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介绍了智能数字型强震观测系统,给出了其技术指标,组成结构及特点,该系统采用固态存储,智能编程控制,Win95界面等先进的设计思想,测试结果证明,该系统可满足一般强震观测的要求。 相似文献
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The nano- and macro-wear characteristics of calcium titanate, single crystal ferrite and polycrystalline ferrite were investigated using nano-scratch testing and wear bar testing. Nano- and micro-indentations were made to determine nano- and micro-hardness, and nano-scratch testing was used to evaluate relative wear rates on the nano-scale. The macro-wear characteristics of the various head materials against metal particle tapes was investigated as a function of tape speed using wear bars mounted in a DLT tape drive. The micro-indentation method was used to investigate wear of the head/tape interface in a linear tape drive. The results from nano- and macro-wear tests were analysed and correlated with the microstructure of the materials. 相似文献