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31.
Neuromorphic computing systems that are capable of parallel information storage and processing with high area and energy efficiencies, offer important opportunities for future storage systems and in‐memory computing. Here, it is shown that a carbon dots/silk protein (CDs/silk) blend can be used as a light‐tunable charge trapping medium to fabricate an electro‐photoactive transistor synapse. The synaptic device can be optically operated in volatile or nonvolatile modes, ensuring concomitant short‐term and long‐term neuroplasticity. The synaptic‐like behaviors are attributed to the photogating effect induced by trapped photogenerated electrons in the hybrid CDs/silk film which is confirmed with atomic force microscopy based electrical techniques. In addition, system‐level pattern recognition capability of the synaptic device is evaluated by a single‐layer perceptron model. The remote optical operation of neuromorphic architecture provides promising building blocks to complete bioinspired photonic computing paradigms.  相似文献   
32.
Integer mapping is critical for lossless source coding and has been used for multicomponent image compression in the new international image compression standard JPEG 2000. In this paper, starting from block factorizations for any nonsingular transform matrix, we introduce two types of parallel elementary reversible matrix (PERM) factorizations which are helpful for the parallelization of perfectly reversible integer transforms. With improved degree of parallelism and parallel performance, the cost of multiplications and additions can be, respectively, reduced to O(logN) and O(log2N) for an N by N transform matrix. These make PERM factorizations an effective means of developing parallel integer transforms for large matrices. We also present a scheme to block the matrix and allocate the load of processors for efficient transformation  相似文献   
33.
The write/erase characteristics of Germanium nanocrystal memory device are modeled using single-charge tunneling theory with quantum confinement and Coulomb blockade effects. A trap model is proposed to describe the retention characteristic of the nanocrystal memory. The impact of nanocrystal size, tunnel-oxide thickness, and high-k tunnel material is studied, and the suitability of the nanocrystal memory devices for nonvolatile memory and DRAM applications is discussed. Issues related to the scaling limit of the nanocrystal memory device are investigated.  相似文献   
34.
网络技术的高速发展给使用者带来高效信息交互的同时,也带来了网络安全和管理上的新问题,本文在分析可信网络连接规范的基础上,结合各种网络访问控制技术,对此规范进行了扩展,形成了可信网络访问控制模型,同时基于此模型对可信网络访问控制系统的关键技术进行了分析,为可信网络访问控制系统的设计和部署提供参考.  相似文献   
35.
Twenty cows were assigned at parturition to two groups to study metabolic effects of continuous intravenous infusions of glucagon. Groups were control cows and cows treated with glucagon at 10 mg/d for 14 d starting at d 21 postpartum. Daily blood samples and nine liver biopsies were taken from d 7 to 49 postpartum. Plasma glucagon increased six- to seven-fold during infusions of treated cows. Plasma insulin was increased heterogeneously by glucagon infusions. Plasma glucose increased 11.5 and 9.0 mg/dl during wk 1 and 2 of glucagon infusions. No other plasma metabolites tested (nonesterified fatty acids, beta-hydroxybutyrate, and urea N) were affected by glucagon infusions. Liver glycogen decreased by d 2 of glucagon infusion but was repleted to preinfusion values by d 7 and increased to 169% of the preinfusion baseline values at 3 d after cessation of glucagon. Milk production decreased transiently during glucagon infusions. Both milk production and milk protein percentage decreased during glucagon infusion, which could imply a decreased availability of amino acids for milk protein synthesis. Feed intakes did not increase during glucagon infusions, which was in contrast to the control group. Results indicated that glucagon infusions caused liver glycogenolysis initially and probably enhanced gluconeogenesis but glucagon did not appear to increase lipolysis from adipose tissue in these early lactating dairy cows.  相似文献   
36.
羧甲基淀粉糊性质的研究   总被引:8,自引:0,他引:8  
本文对羧甲基淀粉糊性质进行了详细的研究,包括糊的冷热粘度稳定性、凝沉性、冻融稳定性、透明度、pH值和介质(蔗糖,氯化钠)对糊粘度性质的影响。结果表明,淀粉经过羧甲基化后,糊的热粘度稳定性大为降低,冷粘度稳定性增加;在pH3.5~8.5范围内,有较好的耐酸碱稳定性;10%蔗糖对糊粘度性质影响不明显,添加氯化钠会使糊化温度升高,峰值粘度降低,凝沉性增大;羧甲基淀粉具有易糊化,糊凝沉性低,冻融稳定性好和透明度高的优良性质。  相似文献   
37.
软装企业的产品图库构成是由多方生产型企业提供,两者的经营模式、产品管理特点、目的各不相同。根据软装企业对产品信息分类编码的需求,提出了一种新颖的基于设计活动时达到快速检索与调配为目的的产品分类编码结构,对产品的编码结构设计是以检索要素及调配顺序为基本出发点,得出一个以10位数的家具产品编码规则和结构。  相似文献   
38.
The pellicles formation, microbial changes and lactic acid utilisation during the aerobic deterioration of Sichuan pickle were discussed in this study. By plate counting, chemical detection and HPLC analysis, the aerobic deterioration of Sichuan pickle was featured by microbial growth, pellicle formation, lactic acid decrease and pH elevation. Bacteria dominated in pellicles and the pellicles present morphological change from smooth to wrinkly along with the aerobic deteriorating process. Nine species of bacteria were identified and responsible for the pellicle formation. Combined with Lactobacillus plantarum, eight pellicle‐forming bacteria were the dominant lactic acid consuming organisms in deteriorating Sichuan pickle. Especially under the harsh acid condition of the early deteriorating period, Lb. plantarum, pellicle‐forming bacteria Bacillus amyloliquefaciens, B. subtilis and Citrobacter freundii participated in the pellicles, utilised lactic acid and increased the brine pH effectively. Sequence analysis of 16S rDNA libraries suggested that the resulting pH of 4.8–5.0 initiated the growth of more undesirable organisms, and the pellicle bacterial diversity changed greatly compared with that in the early deteriorating period. The study indicated the important role of pellicles in the initiation of Sichuan pickle's aerobic deterioration and enhanced our ability to understand and potentially control the aerobic deterioration.  相似文献   
39.
采用芦荟鲜叶生产芦荟工业原料是实现芦荟产业化的基础,本文论述了主要芦荟工业原料生产工艺,总结了主要芦荟工业原料的产品分类和产品规格,芦荟工业原料可作为食品或化妆品原料使用。  相似文献   
40.
The preventive effect of various antioxidants on the formation of mutagenic compounds such as trans,trans‐2,4‐decadienal in degummed peanut oil (DPO) fumes was investigated. The mutagenicity of the DPO fumes was significantly reduced by antioxidants added before heating. The addition of antioxidants increased the smoke point and oxidative stability of DPO and decreased the yield of oil fumes and the amount of mutagens. Butylated hydroxyanisole and butylated hydroxytoluene were more effective than natural antioxidants in reducing the amount of four enal compounds in fumes from DPO. Thus edible cooking oil with a high smoke point, less fume and lower mutagenicity might be developed with an appropriate antioxidant. Copyright © 2004 Society of Chemical Industry  相似文献   
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