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991.
现有的网络安全设备存在许多安全隐患,该文提出需要建立高效稳固的网络安全设备平台。而如何建立该平台的内核是解决问题的关键。文章通过对各种内核构建技术和扩展技术的分析比较,提出一种基于外内核扩展的模型。并对其中采用的关键技术进行详细的描述,目标是获得平台的高效稳固性。经过对实验平台的测试,该平台能为网络安全设备提供良好的运行环境,较好地完成各种安全设备的开发测试工作。 相似文献
992.
提出了KDD中数据预处理的一种基本算法.针对数据库中的属性,利用非监督学习算法,在获取了面向任务的目标数据子集的基础上,利用混合优化算法进行特征子集的选取.分析了遗传算法和混合遗传算法用于特征子集选择的基本算法,仿真实验说明了混合优化算法的有效性和可行性. 相似文献
993.
Alex M. Ruderman Seung-Kyum Choi Roger J. Jiao 《Journal of Intelligent Manufacturing》2013,24(3):641-652
Design chain management requires many decision makers throughout the product development process. It is critical to reduce complexity and uncertainty of the design process by correctly modeling subjective data associated with decision makers’ preferences. This paper aims at using decision support to find optimal designs by modeling respondent preferences and trade-offs with consideration of uncertainty. Specifically, a simulation-based ranking methodology is implemented and incorporated with traditional conjoint analysis. This process facilitates a schematic decision support process by alleviating user fatigue. In addition, incorporation of uncertainty in the ranking process provides the capability of producing robust and reliable products. The efficacy and applicability of simulation-based conjoint ranking is demonstrated with a case study of a power-generating shock absorber design. 相似文献
994.
Liangyun Liu Yongjiang Zhang Quanjun Jiao Dailiang Peng 《International journal of remote sensing》2013,34(12):4264-4280
Photosynthetic light-use efficiency (LUE) is an important indicator of plant photosynthesis, but assessment by remote sensing needs to be further explored. In this study, two protective mechanisms for photosynthesis, chlorophyll fluorescence (ChlF) and heat dissipation in the deep oxidation state of the xanthophyll cycle, were explored to estimate photosynthetic LUE from canopy radiance spectra. Four independent experiments were carried out on summer maize (C4 plant) on 5 July 2008, and winter wheat (C3 plant) on 18 April 2008, 16 April 2010, and 13 May 2010, by synchronously measuring daily canopy radiance spectra and photosynthetic LUE. The competitive relationship between ChlF and photochemical yield made it possible to estimate photosynthetic LUE. LUE–ChlF models were developed for ChlF at 688 nm (R 2 = 0.72) and 760 nm (R 2 = 0.59) based on the experimental data from 13 May 2010 at the Guantao flux site. The LUE–ChlF models were validated by three independent experiments, and the results showed that the LUE–ChlF relationship was weakened, possibly by variation in species, canopy density, and environmental conditions. As an easy, rapid, non-intrusive method, a photochemical reflectance index (PRI) provides an instantaneous assessment of dynamic photosynthetic LUE. The significant negative relationship between non-photochemical quenching and PRI was confirmed. Although there was a significantly positive relationship between LUE and PRI in all four independent experiments, this was evidently weakened by the canopy and environmental conditions. Difference in PRI (ΔPRI) from the minimum reference PRI around noontime can largely eliminate interference factors. The LUE–ΔPRI model was developed based on experimental data from 13 May 2010 at the Guantao flux site (with an R 2 value of 0.85), and validated by the three other independent experiments. The validation result indicated that different species can markedly affect the precision of the PRI difference method. 相似文献
995.
To improve the quality of strip thickness, synchronisation control is investigated for cold rolling mills driven by dual-cylinder electro-hydraulic servo systems. Realising synchronised control in hydraulic automatic gauge control (HAGC) systems of cold rolling mills has challenges with not only the inherent nonlinearities of hydraulic servo systems and uncertainties of load variation but also measurement delay of strip thickness. Since all states are not measurable in practice, output feedback robust synchronisation control problem should be addressed for uncertain nonlinear systems with output delay. Thus, a reduced-order observer-based robust synchronous controller is presented by employing Lyapunov functional stability theory. The controller designed by incorporating the integral of the position synchronisation error of two pistons into state variables successfully guarantees asymptotic convergence to zero of both tracking errors and synchronisation error simultaneously regardless of the nonlinearities and uncertainties as well as the measurement delay. Simulation results in a model obtained from a real cold strip rolling mill demonstrate the effectiveness of the approach. 相似文献
996.
为了解决微机械陀螺仪驱动和检测模态耦合的问题,提出了一种新型的双质量块双线振动结构方案。根据微陀螺的结构和工作原理,对其驱动和检测模态进行了理论分析,给出了简化的动力学方程,并利ANSYS有限元分析软件进行了数值仿真,以验证设计思想的正确性。 相似文献
997.
动态ERP系统中Ajax/SOA系统架构模型的构造 总被引:2,自引:0,他引:2
为了指导动态ERP系统的开发,引入Ajax的客户端,与基于SOA的服务器端之间相配合和协调,既继承了轻量级客户端/服务器端的应用优势,又满足企业的需求变化,是一种可伸缩的和易扩展的Web应用程序实现方式。依据Client/Server-Brow-ser/Server-Ajax/SOA的思路,从物理视角和逻辑视角构造一个融合Ajax技术的SOA系统架构模型,并给出模型的实现策略以及Ajax技术在其中的应用,完善了动态ERP系统的设计机制。 相似文献
998.
基于正交解调的超宽带接收机数据采集系统设计 总被引:1,自引:0,他引:1
根据超宽带接收机信号处理的需要,设计并实现了一套基于正交解调的超宽带脉冲体制接收机数据采集系统。介绍了系统的硬件部分和软件部分,特别是提出了I/Q正交解调及脉冲体制超宽带信号幅相误差校正方案。实际应用表明,该系统达到了实时高速稳定数据采集的要求。 相似文献
999.
1000.
为从界面吸附以探讨含有奥克托金(HMX)和铝粉的固体推进剂的键合剂,采用Material Studio软件Discover模块和COMPASS力场,在不同温度条件下,分别模拟常用的三(-2甲基氮丙啶-1)氧化磷(MAPO)和三乙醇胺(TEA)键合剂在HMX晶体表面和铝粉(Al2O3)表面的吸附后发现:(1)MAPO和TEA在Al2O3表面的吸附能远大于在HMX晶体表面的吸附能;(2)TEA对HMX晶体表面的吸附能高于MAPO,可以判定在该体系下TEA作为HMX键合剂效果优于MAPO,数值模拟结果同实验摹本吻合;(3)数值模拟结果表明,随着温度升高,界面吸附能力先增后减. 相似文献