基于虚拟仪器的差分功耗分析攻击平台

差分功耗分析攻击利用嵌入式加密系统功耗泄漏信号来获取加密系统密钥,将穷举问题转化为数据采集、处理问题.在对DES加密嵌入式系统攻击实验中,基于虚拟仪器的差分功耗分析平台令差分功耗分析攻击的数据采集过程由虚拟仪器应用程序控制进行,而后再对采集的功耗进行分析,能够快速、准确地找到加密系统密钥.较传统的穷举攻击而言,减少了消耗的时间和成本.     

The integration of image segmentation maps using region and edgeinformation

We present an algorithm that integrates multiple region segmentation maps and edge maps. It operates independently of image sources and specific region-segmentation or edge-detection techniques. User-specified weights and the arbitrary mixing of region/edge maps are allowed. The integration algorithm enables multiple edge detection/region segmentation modules to work in parallel as front ends. The solution procedure consists of three steps. A maximum likelihood estimator provides initial solutions to the positions of edge pixels from various inputs. An iterative procedure using only local information (without edge tracing) then minimizes the contour curvature. Finally, regions are merged to guarantee that each region is large and compact. The channel-resolution width controls the spatial scope of the initial estimation and contour smoothing to facilitate multiscale processing. Experimental results are demonstrated using data from different types of sensors and processing techniques. The results show an improvement over individual inputs and a strong resemblance to human-generated segmentation     

Softening–melting–dripping characteristics and evolution mechanism of vanadium-bearing titanomagnetite carbon composite briquette used as novel blast furnace burden

Vanadium-bearing titanomagnetite carbon composite briquette (VTM-CCB) was proposed as an innovative and promising blast furnace burden to realize low-carbon and...     

不同压紧件对IEGT工作表面压应力分布的影响

介绍了大功率器件IEGT在压装中,不同结构形式的压紧件对IEGT工作面压应力分布的影响,结合实例并通过有限元模拟及实验验证来确定压紧件的结构形式,以保证IEGT工作面压应力分布均匀,满足其在电力系统中使用要求。     

基站电磁环境测试方法的比较与分析

GSM移动通信基站电磁辐射测量常用的方法有两种,一种是用频谱分析仪和定向天线进行测量,计算出辐射功率密度;另一种是用射频电磁辐射仪,可以直接读出辐射功率密度.对实际运行的基站,两种方法的测量结果不一致,通过在实验室的反复实验,分析出这两种测量方法的特点,找到了测量结果不一致的原因.电磁辐射的测量不仅要了解测量方法的特点,还要了解辐射信号的特性,才能给出恰当的测试结论.     

Efficient organic near-infrared photodetectors based on lead phthalocyanine/C60 heterojunction

High efficiency organic small molecule near-infrared photodetectors (NIR-PDs) based on a lead phthalocyanine/C₆₀ planar heterojunction are demonstrated. The NIR-PDs show a broad-band response that extends to 1100 nm. The performance of the NIR-PDs is improved by using CuI as anode buffer layer. The optimized NIR-PD exhibits a response peak at about 900 nm with external quantum efficiencies (EQEs) of 19.7% at zero bias and 35.1% at −6 V, which are higher than other small molecule NIR-PDs reported. Comparable EQEs of 18.0% at zero bias and 33.2% at −6 V are found in the NIR-PD by further using 4,7-diphenyl-1,10-phenanthroline as cathode buffer layer. Meanwhile, the dark current is significantly reduced, which results in a high detectivity of 2.34 × 10¹¹ Jones at zero bias, which is among the highest detectivities reported for organic small-molecule NIR-PDs. Besides, the NIR-PDs show a reliable stability in ambient condition.     

Photoelectrochemical Synthesis of Ammonia with Black Phosphorus

Efficient production of ammonia using environmentally friendly techniques under ambient conditions is crucial to renewable energy storage and industrial applications, and catalysts with new reaction pathways are highly desirable. In this work, black phosphorus (BP) is used as a metal‐free 2D catalyst for the photoelectrochemical (PEC) nitrogen reduction reaction (NRR). The electrode is fabricated by layer‐by‐layer assembly of BP nanosheets on an indium tin oxide substrate. The PEC NRR activity in the N₂ saturated aqueous electrolyte without a sacrificial agent is excellent, as exemplified by an ammonia yield rate of 102.4 µg h^?1 mgcat.^?1 and Faradaic efficiency of 23.3% at ?0.4 V, which are the best among nonmetal catalysts for synthesis of ammonia by photocatalysis and electrocatalysis. Furthermore, the BP electrode shows excellent stability after 6 consecutive cycles. The excellent PEC catalytic properties are attributed to the light excitation enhanced electrocatalytic process and that the external bias promoted photocatalytic process improves ammonia production synergistically. The results not only demonstrate the great potential of BP in PEC catalysis, but also identify a promising technique to produce ammonia under ambient conditions using solar energy and electric energy.     

尿素高压新设备役中发生的典型问题综述

综述新投用的尿素高压静设备,动设备及高压管理,阀门在近两年运行中发生的典型问题,提出根本的管理措施。     

再生热塑性聚氨酯/聚氯乙烯共混材料性能的研究

通过对再生热塑性聚氨酯与聚氯乙烯共混材料力学性能等的研究,发现当ＴＰＵＲ含量在４０％时具有较好综合性能。