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1.
IntegratedVP-BasedControlStrategiesforATMSurvivableNetworks¥ChenShanzhi;ChengShiduan;andChenJunliang(StateKeyLaboratoryofSwit... 相似文献
2.
In this paper we propose a cross-layer accelerated self-healing (CLASH) system which “repairs” its wearout issues in a physical sense through accelerated and active recovery, by which wearout can be reversed while actively applying several accelerated self-healing techniques, such as high temperature and negative voltages. Different from previous solutions of coping with wearout issues (e.g. BTI) by “tolerating”, “slowing down” or “compensating”, which still leave the irreversible (permanent) wearout component unchecked, the proposed solution is able to fully avoid the irreversible wearout through periodic rejuvenation, and this is inspired by the explored frequency dependent behaviors of wearout and (accelerated and active) recovery based on measurements on FPGAs. We demonstrate a case where the chip can always be brought back to the fresh status by employing a pattern of 31-h regular operation (under room temperature and nominal voltage) followed by a 1-h accelerated self-healing (under high temperature and negative voltage). The proposed system integrates the notions of accelerated self-healing across multiple layers of the system stack. At the circuit level, a negative voltage generator and heating elements are designed and implemented; at the architecture level, the core can be allocated in a way such that the dark silicon or redundant resources can be healed by active elements; at the system level, right balance of stress and accelerated/active recovery can be employed by the system scheduler to fully mitigate the wearout; various wearout sensors act as the media between different layers. Overall, these techniques work together to guarantee that the whole system performs for more of the time at higher levels of performance and power efficiency by fully taking advantage of the extra opportunities enabled by the accelerated self-healing. 相似文献
3.
目前我军无人机装备采用事后维修、定期维修、预防性维修等维修保障方式,存在故障诊断及修复能力差、维修资源繁多、保障费用急剧增长等问题。充分考虑我军无人机装备技术特点及现行维修保障体制,文中创新性地提出了构建适合我军无人机装备的自主式保障系统;并对系统组成、故障模式影响及危害性分析、测试性设计技术、机载故障快速诊断及自修复技术、预测与健康管理技术、分布式信息融合技术等关键技术进行重点研究。该系统为我军新型信息化装备提供了新的维修保障模式,并可提高我军无人机装备的一体化、精确化保障水平。 相似文献
4.
《International Journal of Pavement Engineering》2012,13(8):884-893
ABSTRACTEngineered Cementitious Composites (ECC) with high ductility has been recognised to be a high performance and durable alternative to the construction material in civil engineering field. In this paper, ECC material was proposed to be applied on the long-span steel bridge deck overlay. Herein we studied the feasibility of this application via integration of ECC’s material performances and stress response of structure using finite element analysis. The results show that ECC material could overcome the brittleness of normal concrete, featuring high tensile strain/deformability capacity under tension/flexural load, as well as higher flexural strength and fatigue life, compared with normal asphalt/concrete materials. Furthermore, the self-healing capacity in ECC helps the crack seal itself, as a result, recovers its water permeability coefficient and resistance to chloride ion penetration to nearly the same level as undamaged ones. By integrating ECC’s flexural fatigue behaviour and finite element analysis, it can be concluded that ECC is feasible to be a candidate material for the steel bridge overlay. The application of ECC is expected to greatly extend the service life of steel bridge overlay meanwhile be with thinner thickness compared with normal bridge deck overlay structure, resulting in a more sustainable overlay. 相似文献
5.
Self-healable electroactive carboxymethyl cellulose/polythiophene/acid hydrolyzed cellulose (CMC/PTh/AHC) hydrogels were successfully fabricated. AHC particles dispersed well in the CMC matrix improving hydrogels thermal stability. The electro-responsive performance of the hydrogels was investigated with respect to bending angle and bending sensitivity. The results showed that under an applied electric field, the CMC/PTh/AHC hydrogels bend toward a cathode electrode. In addition, the electroactive performance of the hydrogels decreased with increased AHC content. The CMC/PTh/AHC10 (10 wt.% AHC) hydrogel exhibited the shortest induction time (τind) of 3.35 ± 0.56 s. For self-healing, it was found that the hydrogel with addition of 2 wt.% AHC had the highest self-healing efficiency on both tensile strength and elongation at break (93.37 ± 3.17% and 99.35 ± 12.11%, respectively). While the self-healing efficiency on bending angle was 82.73 ± 14.55%. The results demonstrated that the properties of the CMC/PTh/AHC2 hydrogel were close to its original properties after healing for 24 h. The results demonstrated that the CMC/PTh/AHC hydrogel can be utilized as an actuator or artificial muscle using electrical stimulus. 相似文献
6.
Light-responsive cellulose nanocrystal@polydopamine (CNC@PDA) modified fluorinated polyacrylate was synthesized by Pickering emulsion polymerization with light-responsive block copolymer modified CNC@PDA as stabilizer. The epoxy groups in poly(acrylic acid-co-acrylamide)-b-poly(glycidyl methacrylate)-b-poly(hexafluorobutyl acrylate-co-coumarin) amphiphilic triblock copolymer reacted with the hydroxyl and amino groups on the surface of CNC@PDA to form the modified CNC@PDA. The successful preparation of modified CNC@PDA was confirmed by means of FT-IR, XRD, TG, UV–Vis, surface tension measurement, and X-ray photoelectron spectroscopy (XPS) techniques. The results showed that the modified CNC@PDA had light-responsive and amphiphilic properties, and could be used as stabilizer to form stable Pickering emulsion. And the influence of modified CNC@PDA dosage on emulsion polymerization and film performance was systematically studied. The latex particle size decreased initially with increasing modified CNC@PDA dosage, from 0.6 to 1.0 wt%, and then increased. The mechanical, self-healing, and water–oil repellent properties of film were enhanced initially with increasing modified CNC@PDA dosage, from 0.6 to 1.0 wt%, and then declined. Atomic force microscope confirmed that the latex film had a rough surface. Moreover, the latex film comprising 1.0 wt% modified CNC@PDA presented not only high tensile strength (4.92 MPa), large elongation at break (657.70%), and superior oil/water repellency but also excellent self-healing property. 相似文献
7.
8.
大中型光伏电站并网发电给电力系统的安全稳定及经济运行调度带来了很大的困扰和全新的挑战。基于逆变器调相控制的无功遥调技术的成功研发运用将完全改变传统的光伏发电站无功补偿的概念。以理论分析和实践验证证实:配置满足国家标准(GB/T-19964—2012《光伏发电站接入电力系统技术规定》)逆变器的光伏发电站无须额外配置无功补偿装置(SVC或SVG),其无功出力范围和动态响应时间足以满足电网对新接入电源的要求。这将为造价昂贵的光伏发电站节省大量资金,也可避免无功补偿装置的运行损耗。 相似文献
9.
微胶囊填充型自修复涂层材料研究进展 总被引:2,自引:2,他引:2
微胶囊填充型自修复聚合物及其复合材料是近年来高分子科学界的研究热点之一.总结了微胶囊填充型自修复涂层的修复机理.概括了常见的微胶囊填充型自修复涂层体系,包括双环戊二烯-Grubbs固化剂体系、环氧树脂固化剂体系以及极性溶剂-环氧树脂体系等,并对各体系的组成、微胶囊的稳定性及其影响因素、当前研究现状及未来发展前景进行了总结.介绍了常见的微胶囊制备方法,其中主要有原位聚合法和界面聚合法,并对各方法的原理、特点、应用范围及自身优缺点进行了介绍.对微胶囊填充型自修复涂层的性能(包括力学性能和耐蚀性能)评价方法进行了总结.自修复微胶囊的加入使涂层的断裂韧性修复效率超过90%,微胶囊使涂层层间附着力的修复效率达到87%.电化学实验可以从腐蚀电流和阻抗方面等证明微胶囊填充型自修复涂层比普通涂层具有更好的耐蚀性能,同时利用电化学实验也可以对微胶囊填充型自修复涂层的修复过程进行解释说明.最后对微胶囊填充型自修复涂层材料在不同领域的应用进行了总结,并针对微胶囊填充型自修复涂层材料未来的发展方向进行了展望. 相似文献
10.
通过物理屏蔽作用把金属和腐蚀环境进行隔绝的有机涂层,由于其经济、有效和操作方便的特点而成为主要的防腐措施。然而,环境因素往往不可避免地导致涂层产生裂纹,并最终导致涂层失效。具有自修复能力的涂层在发生破损后,由于其能够主动的修复涂层的破损部位而得到了广泛的关注。相对于具有单一物理屏蔽性能的涂层,具有自修复性能的涂层可以降低破损涂层维修期间的人力和物力成本,在未来的发展中具有很大的潜力。本文根据自修复涂层的愈合机理及其发展历程,把自愈合涂层分为自主修复型、借助外部刺激的非自主修复型和针对特定环境能够做出有效响应的智能自修复涂层,并对其研究现状及优缺点进行阐述。 相似文献