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确定性删除将外包数据的删除问题转换为密钥的安全管控和删除问题,使得留存于云服务提供商和数据使用者处的外包数据是失效、不可恢复的。但是,现有的确定性删除方案大多是在资源充裕的计算机和智能手机上设计和实现的,无法应用于资源受限的嵌入式设备。本文提出了适用于JavaCard平台的云数据确定性删除方法。在该方法中,密钥的使用条件可以是时间,也可以是次数,数据属主可以根据其需要选取一种条件以实现密钥在数据使用者端的受限使用。对于这两种使用条件,数据使用者都可以将密钥及使用条件安全保存在本地,节省通信开销。当密钥使用条件满足时,JavaCard用密钥解密数据;当密钥使用条件不满足时,JavaCard安全删除密钥,并生成可公开验证的密钥删除证据。实验和对比分析表明,本文方案性能开销合理,能够实现预期目的,可以应用于嵌入式设备。 相似文献
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GaAs Based InAs/GaSb Superlattice Short Wavelength Infrared Detectors Grown by Molecular Beam Epitaxy
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InAs/GaSb superlattice (SL) short wavelength infrared photoconduction detectors are grown by molecular beam epitaxy on GaAs(O01) semi-insulating substrates. An interfacal misfit mode AISb quantum dot layer and a thick GaSb layer are grown as buffer layers. The detectors containing a 200-period 2 ML/S ML InAs/GaSb SL active layer are fabricated with a pixel area of 800×800 μm^2 without using passivation or antirefleetion coatings. Corresponding to the 50% cutoff wavelengths of 2.05μm at 77K and 2.25 μm at 300 K, the peak detectivities of the detectors are 4 × 10^9 cm·Hz^1/2/W at 77K and 2 × 10^8 cm·Hz1/2/W at 300K, respectively. 相似文献
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2~4 μm波段是非常重要的红外大气窗口,工作在这个波段的激光器在气体检测,医疗美容和工业加工领域具有十分巨大的应用价值。锑化物半导体材料低维结构具有窄禁带直接跃迁发光的独特优势,是实现中红外波段半导体激光器的理想材料体系。近年来,国内外锑化物半导体激光器研究不断取得重要进展,先后实现了量子阱发光的波长拓展、大功率单管和阵列激光器的室温连续激射,也实现了多波段的单模激光器的室温连续工作。锑化物半导体低维材料组分复杂、界面钝化性质特殊,材料外延和工艺制备技术难度较大。文中从锑化物半导体激光器的基本原理出发,综述了国内外研究现状,介绍了锑化物材料低维结构激光器的设计方案、关键制备技术的主要进展,分析了今后该类激光器性能优化的重点研发方向等。 相似文献
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High quality above 3-μm mid-infrared InGaAsSb/AIGaInAsSb multiple-quantum well grown by molecular beam epitaxy
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The GaSb-based laser shows its superiority in the 3-4 ~tm wavelength range. However, for a quantum well (QW) laser structure of InGaAsSb/AIGaInAsSb multiple-quantum well (MQW) grown on GaSb, uniform content and high com- pressive strain in InGaAsSb/A1GaInAsSb are not easy to control. In this paper, the influences of the growth tempera- ture and compressive strain on the photoluminescence (PL) property of a 3.0μm lnGaAsSb/A1GaInAsSb MQW sample are analyzed to optimize the growth parameters. Comparisons among the PL spectra of the samples indicate that the Ino.485GaAso.184Sb/Alo.3Gao.45Ino.25Aso.22Sbo.78 MQW with 1.72% compressive strain grown at 460 ~C posseses the op- timum optical property. Moreover, the wavelength range of the MQW structure is extended to 3.83 μm by optimizing the parameters. 相似文献
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High quality above 3-μm mid-infrared InGaAsSb/AlGaInAsSb multiple-quantum well grown by molecular beam epitaxy
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The GaSb-based laser shows its superiority in the 3–4 μm wavelength range. However, for a quantum well(QW) laser structure of InGaAsSb/AlGaInAsSb multiple-quantum well(MQW) grown on GaSb, uniform content and high compressive strain in InGaAsSb/AlGaInAsSb are not easy to control. In this paper, the influences of the growth temperature and compressive strain on the photoluminescence(PL) property of a 3.0-μm InGaAsSb/AlGaInAsSb MQW sample are analyzed to optimize the growth parameters. Comparisons among the PL spectra of the samples indicate that the In0.485GaAs0.184Sb/Al0.3Ga0.45In0.25As0.22Sb0.78MQW with 1.72% compressive strain grown at 460 C posseses the optimum optical property. Moreover, the wavelength range of the MQW structure is extended to 3.83 μm by optimizing the parameters. 相似文献
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