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31.
分析了国内外物联网安全政策、技术、标准、产业等形势,重点强调了当前我国物联网发展中存在的安全风险,包括大连接环境下的设备风险、物联网网络本身安全风险以及物联网上承载的各类应用安全风险,提出了打造以密码为核心的物联网安全体系,加速新技术在物联网安全的应用,以新基建为契机建立物联网领域安全设备泛在化部署新体系,以多层次立体式理念确保物联网安全,呼吁供给侧需求侧建立安全协同新机制,共同促进物联网产业安全可持续发展。 相似文献
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Information‐Centric Networking (ICN) has been accepted to overcome some weaknesses of the current Internet architecture, showing that “what is being exchanged” is more important than “who are exchanging information.” Given the inadequate considerations on Quality of Service (QoS) and energy saving in ICN routing, we propose in this paper a routing algorithm to enhance the two aspects. At first, on one hand, Cauchy distribution is used as a fuzzy model to evaluate users' QoS requirements, such as bandwidth, delay, and error rate; on the other hand, we formulate energy saving problem to evaluate the green quality of routing algorithm. Then, we design a link selection approach by considering QoS and energy saving, which belongs to a multi‐objective decision problem resolved by intelligent drops algorithm. Finally, we implement the proposed algorithm and compare it with the famous adaptive forwarding mechanism in terms of some significant metrics, and the experimental results reveal that the proposed algorithm is more efficient. 相似文献
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由于器件的快速退化,101.5小时似乎成了Znse基蓝绿色半导体激光器难于逾越的寿命极限。分析退化机制,发现在强电流注入的半导体激光器中,热退化具有重要影响。研究表明,用作载流子限制层的宽带Ⅱ-Ⅵ族四元合金(如ZnMgSSe)只能对ZnSe中的电子有效地限制,无法对空穴很好地限制;而对BeTe,却只能对空穴进行有效的限制,无法对电子很好地限制。这导致ZnSe(或BeTe)活性层空穴(或电子)漏电发热,引起退化。本文提出以ZnSe/BeTe超晶格为蓝绿发光层,并用包络函数理论具体计算了阱宽、垒宽对载流子能级的不同影响,考察了ZnSe、BeTe厚度比和超晶格周期对带隙、载流子限制能力的调节。为研制新型长寿命蓝绿色半导体激光器提供了一条新的途径。 相似文献
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《Energy Policy》2015
India has committed large investments to energy infrastructure assets-power plants, refineries, energy ports, pipelines, roads, railways, etc. The coastal infrastructure being developed to meet the rising energy imports is vulnerable to climate extremes. This paper provides an overview of climate risks to energy infrastructures in India and details two case studies – a crude oil importing port and a western coast railway transporting coal. The climate vulnerability of the port has been mapped using an index while that of the railway has been done through a damage function for RCP 4.5.0 and 8.5 scenarios. Our analysis shows that risk management through adaptation is likely to be very expensive. The system risks can be even greater and might adversely affect energy security and access objectives. Aligning sustainable development and climate adaptation measures can deliver substantial co-benefits. The key policy recommendations include: i) mandatory vulnerability assessment to future climate risks for energy infrastructures; ii) project and systemic risks in the vulnerability index; iii) adaptation funds for unmitigated climate risks; iv) continuous monitoring of climatic parameters and implementation of adaptation measures, and iv) sustainability actions along energy infrastructures that enhance climate resilience and simultaneously deliver co-benefits to local agents. 相似文献
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Mathematical Modeling of Heat and Mass Transfer during Convective Dehydration of an Anisotropic Cylindrical Foodstuff 下载免费PDF全文
B. Abbasi Souraki 《亚洲传热研究》2015,44(3):257-271
Two‐dimensional, unsteady‐state mass transfer was studied for air drying of an anisotropic finite cylindrical body. A mathematical model was developed for predicting the temperature of the drying sample at any time and moisture in any position in the drying sample at any time. The anisotropic nature of the drying material was considered in the mathematical model by taking into account the different moisture diffusivities in the axial and radial directions. A cut fresh green bean was used as an anisotropic material and a pilot‐scaled dryer was set up to investigate the drying behavior of this foodstuff. Several length‐to‐diameter ratios of fresh green beans were considered and the mathematical model was validated by comparison of the predicted values of average moisture content with the experimental data. The model was used to predict the moisture distributions inside the drying samples. Different moisture content distributions in the axial and radial directions during drying confirms the anisotropic nature of cut green bean samples. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21119 相似文献
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以准静态近似为前提,采用格林函数法对声表面波换能器进行分析。推导了声表面波换能器激励电压与表面电荷之间的关系,计算了加载单位激励电压时换能器上的静态电荷分布并与有限元法计算结果进行比较。格林函数法的换能器的分析可用来为声表面波器件设计优化进行参数计算,及为其建模提供精确的数据。 相似文献
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文章针对现有互联网由于原始设计模式方面的不足,难以满足泛在、移动用户的多元化网络服务需求的问题,创造性地提出全新的泛在、移动互联网体系理论与总体框架;创建一种。基础设施层。模型与理论,解决用户在任何地点、任何时间、以任何方式接入到互联网的问题;建立一种。普适服务层”模型与理论,实现对普适服务的支持;并提出新网络体系下的移动性管理机制。新的网络体系结构可克服现有互联网存在的弊端,有效满足泛在、移动方面的多元化网络服务需求。 相似文献