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61.
62.
An analytical forward model and numerical algorithm for retrieving the parameters of water cloud of earth atmosphere from optical measurements carried out by satellite-based lidars is presented. The forward model, based on the analytical solution of the radiative transfer equation, is used to fit the temporal profile of the laser light pulses backscattered from the cloud layers. The cloud parameters extracted from the analysis at each position on earth include the transport mean free path, the average radius of water drops, the density of drops, the scattering length, the scattering cross section, the anisotropy factor, and the altitude of top level of major clouds. Also estimated is the possible thickness of cloud layers. The efficacy of the approach is demonstrated by generating parameters of water cloud using the data collected by NASA's cloud-aerosol lidar and infrared pathfinder satellite observations (CALIPSO) satellite when it passed through North America on August 7, 2007. 相似文献
63.
With the advent of microservice-based software architectures, an increasing number of modern cloud environments and enterprises use operating system level virtualization, which is often referred to as container infrastructures. Docker Swarm is one of the most popular container orchestration infrastructures, providing high availability and fault tolerance. Occasionally, discovered container escape vulnerabilities allow adversaries to execute code on the host operating system and operate within the cloud infrastructure. We show that Docker Swarm is currently not secured against misbehaving manager nodes. This allows a high impact, high probability privilege escalation attack, which we refer to as leadership hijacking, the possibility of which is neglected by the current cloud security literature. Cloud lateral movement and defense evasion payloads allow an adversary to leverage the Docker Swarm functionality to control each and every host in the underlying cluster. We demonstrate an end-to-end attack, in which an adversary with access to an application running on the cluster achieves full control of the cluster. To reduce the probability of a successful high impact attack, container orchestration infrastructures must reduce the trust level of participating nodes and, in particular, incorporate adversary immune leader election algorithms. 相似文献
64.
随着智能手机的普及和3G技术的发展,信息呈指数式增长,从海量的信息中提取出用户感兴趣的内容已成为电子商务发展的一个重要趋势,然而传统的推荐策略已不能满足用户的需求.为此,基于移动云计算和位置信息,提出了一个个性化服务推荐模型解决方案,该方案综合了社交网络和时效性,建立了用户兴趣模型库.基于这个解决方案,在Android平台上,实现了初步的个性化图片推荐模型,取得了不错的效果.个性化服务推荐系统具有良好的发展和应用前景,能有效的保留客户,提高电子商务系统的服务能力,带来巨大的效益,具有一定的理论和现实意义. 相似文献
65.
云计算是一种通过互联网将各种资源按照一定的方法整合在一起,以服务的形式向外提供的商业模式,有着良好的发展前景.Agent技术拥有其他技术无法比拟的智能性,并在各个领域都得到了广泛的应用.但Agent软件的系统开发、部署、运行以及维护仍采用传统的技术方案,无论在硬件还是软件设施上都存在着严重的浪费,因此将云计算与Agent技术结合起来,建立基于云计算的Agent平台(AaaS),来解决上述存在的问题,利用虚拟化技术解决硬件资源的浪费,设计开发Agent开发工具箱(ADT)以统一的标准来开发和部署Agent,提供云控制器来实时监测Agent的运行状态,进而动态的解决Agent运行时存在的问题. 相似文献
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67.
Brian C. Sales V. O. Garlea M.B. Stone M. D. Lumsden S. E. Nagler D. Mandrus 《哲学杂志》2020,100(10):1204-1210
ABSTRACTSingle crystals of the underscreened Kondo ferromagnet Yb14MnSb11 were investigated using polarised neutron diffraction and magnetisation measurements. The magnitude and direction of the magnetisation at each of the 9 distinct crystallographic sites was measured using polarised neutron diffraction. A large moment of close to 4.2?μB was found at the unique Mn site. A compensating antiferromagnetic moment of ≈?0.5?μB was found to be distributed uniformly among the remaining Yb and Sb sites, which was not expected from a previous theoretical calculation. The compensating magnetisation, however, is consistent both in size and magnitude with the expected Kondo screening cloud. 相似文献
68.
Effect of chain architecture on the phase transition of star and cyclic poly(N‐isopropylacrylamide) in water 下载免费PDF全文
Na Xue Xing‐Ping Qiu Yougen Chen Toshifumi Satoh Toyoji Kakuchi Françoise M. Winnik 《Journal of Polymer Science.Polymer Physics》2016,54(20):2059-2068
The heat‐induced phase transition of aqueous solutions of Poly(N‐isopropylacrylamide) (PNIPAM) in water is examined for a four‐arm PNIPAM star (s‐PNIPAM), a cyclic PNIPAM (c‐PNIPAM), and their linear counterparts (l‐PNIPAM) in the case of polymers (1.0 g L?1) of 12,700 g mol?1 < Mn < 14,700 g mol?1. Investigations by turbidity, high‐sensitivity differential scanning calorimetry (HS‐DSC), and light scattering (LS) indicate that the polymer architecture has a strong effect on the cloud point (Tc: decrease for s‐PNIPAM; increase for c‐PNIPAM), the phase transition enthalpy change (ΔH decrease for s‐PNIPAM and c‐PNIPAM), and the hydrodynamic radius of the aggregates formed above Tc (RH: c‐PNIPAM < s‐PNIPAM < l‐PNIPAM). The properties of s‐PNIPAM are compared with those of previously reported PNIPAM star polymers (3 to 52 arms). The overall observations are described in terms of the arm molecular weight and the local chain density in the vicinity of the core of the star, by analogy with the model developed for PNIPAM brushes on nanoparticles or planar surfaces. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2059–2068. 相似文献
69.
在分析各项影响因素分级标准的基础上,建立了三维土工网护坡侵蚀稳定性的综合评价体系.针对三维土工网边坡侵蚀稳定性分析中不确定性问题,将云模型理论引入到综合评判中,实现了定性与定量的不确定性转换.通过构建前件云发生器和后件云发生器,利用不确定推理,确定各项评价指标的具体分值.借助层次分析法与敏感度分析确定各项评价指标的权重,进而得出综合评价体系的整体得分.工程实例计算结果证实了模型的实用性和有效性,为三维土工网防护边坡侵蚀稳定性的评价提供了一条新的途径. 相似文献
70.
Poly[(N-isopropylacrylamide-co-acrylamide-co-(hydroxyethylmethacrylate))] [poly(NIPAAm-co-AAm-co-HEMA)] copolymer was synthesized as a new thermoresponsive material possessing a lower critical solution temperature (LCST) around 37 °C in phosphate buffer, pH 7.4, at a solution concentration of 1%, w/v. The influence of polymer concentration on LCST was determined by cloud point measurements and by microcalorimetric analysis. The copolymer was transformed in hydrogel microspheres by suspension reticulation of OH groups with glutaraldehyde. The volume phase transition temperature (VPTT) of microspheres was determined by a new approach, which involves measurement of the increase in concentration of a blue dextran (BD) solution at different temperatures in the presence of dry microspheres. The minimum BD concentration that gives reliable and reproducible results was determined to be 1 mg/ml. However, the higher is the concentration of BD in solution the smaller is the error. Contrary to solution of the linear polymer which displays a sharp phase transition temperature, the dependence of water regain of the hydrogel with temperature lasts from 4 °C to 50 °C. 相似文献