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941.
To improve the embedding efficiency of steganography, syndrome coding based on the coding theory has attracted many researchers’ attentions. In this paper, we make use of the relationship between syndrome coding for minimizing additive distortion and maximum likelihood decoding for linear codes to analyze the main parameters of convolutional codes which influence the embedding efficiency. And, the new syndrome trellis codes based on minimal span generator matrix is proposed. It can be considered an alternative construction of the state-of-the-art syndrome trellis codes (STCs) proposed by Filler and Fridrich recently. Experimental results show that the proposed scheme owns the same embedding performance to STCs and achieve the reduced time complexity and storage requirement meanwhile. 相似文献
942.
电子镇流器开启时由自身电路产生的高电压(冲击电压)会对电路中的器件产生重大影响,有时甚至是致命的。提出1种可排除外界影响的电子镇流器高可靠性测试方法,并以示波器图示曲线显现其波形和实测参数。 相似文献
943.
Nanoparticulate Delivery of Cancer Cell Membrane Elicits Multiantigenic Antitumor Immunity 下载免费PDF全文
Ashley V. Kroll Ronnie H. Fang Yao Jiang Jiarong Zhou Xiaoli Wei Chun Lai Yu Jie Gao Brian T. Luk Diana Dehaini Weiwei Gao Liangfang Zhang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(47)
Anticancer vaccines train the body's own immune system to recognize and eliminate malignant cells based on differential antigen expression. While conceptually attractive, clinical efficacy is lacking given several key challenges stemming from the similarities between cancerous and healthy tissue. Ideally, an effective vaccine formulation would deliver multiple tumor antigens in a fashion that potently stimulates endogenous immune responses against those antigens. Here, it is reported on the fabrication of a biomimetic, nanoparticulate anticancer vaccine that is capable of delivering autologously derived tumor antigen material together with a highly immunostimulatory adjuvant. The two major components, tumor antigens and adjuvant, are presented concurrently in a fashion that maximizes their ability to promote effective antigen presentation and activation of downstream immune processes. Ultimately, it is demonstrated that the formulation can elicit potent antitumor immune responses in vivo. When combined with additional immunotherapies such as checkpoint blockades, the nanovaccine demonstrates substantial therapeutic effect. Overall, the work represents the rational application of nanotechnology for immunoengineering and can provide a blueprint for the future development of personalized, autologous anticancer vaccines with broad applicability. 相似文献
944.
945.
阐述了料位计在煤仓料位测量中的必要性 ,说明了料位计的原理及特点 ,介绍了料位计在火电厂的应用 相似文献
946.
To explore the hot compression behavior and microstructural evolution, fine-grained Al?1.88Mg?0.18Sc? 0.084Er (wt.%) aluminum alloy wires were fabricated with Castex (continuous casting?extrusion) and ECAP-Conform, and their hot compression behavior was investigated at temperatures of 673?793 K and strain rates of 0.001?10 s?1; the microstructures were characterized by optical microscope, X-ray diffractometer, transmission electron microscope, and electron backscattered diffractometer, and the flow stresses were obtained by thermal compression simulator. Microstructural evolution and flow curves reveal that dynamic recovery is the dominant softening mechanism. Continuous dynamic recrystallization followed by dynamic grain growth takes place at a temperature of 773 K and a strain rate of 0.001 s?1; the yielding drop phenomenon was discovered. Hyperbolic sine constitutive equation incorporating dislocation variables was presented, and a power law constitutive equation was established. The stress exponent is 3.262, and the activation energy for deformation is 154.465 kJ/mol, indicating that dislocation viscous glide is the dominant deformation mechanism. 相似文献
947.
用热模拟试验机研究了纯铂在真应变量为0.9、变形温度为550℃~950℃和应变速率为0.01~1 s~(-1)的热塑性变形行为,并对热压缩后的样品进行了金相观察和显微硬度测量。结果表明,纯铂的流变应力随变形温度的升高和应变速率的降低而降低;其热压缩变形过程中软化行为由变形温度和变形速率共同作用决定,一般以动态回复为主,而在低应变速率和高形变温度下以动态再结晶为主,动态再结晶发生造成的软化使纯铂样品的硬度迅速下降。利用Zener-Hollomon参数方程获得了热塑性变形流变应力本构方程,得到纯铂的热变形激活能为208.51 kJ/mol,流变应力拟合公式计算值与实验值的平均误差为5.9%。 相似文献
948.
949.
The goal of Optoelectronics Letters is to rapidly report original,new and important results in the fields of photonics and optoelec-tronics in English,to advance the international academic exchanges.Optoelectronics Letters pays a particularly attention to the cross topics between photonics and electronics.The scope of Optoelectronics Letters is as follows:Novel OEdevices and applications;New materials and functional components;Nano-structures and OE integration;Nano-quantum optoelectronics;Optoelectronic information technology;Sensing,measurement and inspection;Storage and display;Image and information processing;Biomedical photonics,etc. 相似文献
950.