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在惯性约束聚变驱动器终端光学系统中,束匀滑器件前置有许多优点,但它同时也将对频率转换系统的工作状态产生影响.从系统集成优化的观点研究了这种影响,并基于高强度激光非线性传输理论,采用耦合波方程组及微扰理论,模拟计算了连续相位板前置时基频光束通过频率转换系统的三倍频转换效率及出射光束的近远场分布和焦斑形态,提出了优化倍频晶体失谐角和晶体厚度以减小CPP前置对系统性能的影响.模拟计算了频率转换系统优化前后的三倍频转换效率、光束通量对比度和能量集中度,并进行了对比分析.分析结果表明,频率转换系统的优化对减小CPP
关键词:
惯性约束聚变
频率转换系统
连续相位板
系统集成优化 相似文献
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Julio Llorca Cristina GutiérrezElisabeth Capilla Rafael TortajadaLorena Sanjuán Alicia FuentesIgnacio Valor 《Journal of chromatography. A》2009,1216(31):5783-5792
Two innovative integrative samplers have been developed enabling high sampling rates unaffected by turbulences (thus avoiding the use of performance reference compounds) and with negligible lag time values. The first, called the constantly stirred sorbent (CSS) consists of a rotator head that holds the sorbent. The rotation speed given to the head generates a constant turbulence around the sorbent making it independent of the external hydrodynamics. The second, called the continuous flow integrative sampler (CFIS) consists of a small peristaltic pump which produces a constant flow through a glass cell. The sorbent is located inside this cell. Although different sorbents can be used, poly(dimethylsiloxane) PDMS under the commercial twister format (typically used for stir bar sorptive extraction) was evaluated for the sampling of six polycyclic aromatic hydrocarbons and three organochlorine pesticides. These new devices have many analogies with passive samplers but cannot truly be defined as such since they need a small energy supply of around 0.5 W supplied by a battery. Sampling rates from 181 × 10−3 to 791 × 10−3 L/day were obtained with CSS and 18 × 10−3 to 53 × 10−3 with CFIS. Limits of detection for these devices are in the range from 0.3 to 544 pg/L with a precision below 20%. An in field evaluation for both devices was carried out for a 5 days sampling period in the outlet of a waste water treatment plant with comparable results to those obtained with a classical sampling method. 相似文献
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本文采用分区搭接网格技术,对机翼/机身/挂架/短舱复杂组合体进行网格分布,通过分析计算网格对结果的影响,探讨了网格的划分.基于Roe的近似黎曼解的方法,采用S-A湍流模型,通过求解N-S方程,对该组合体外流场/发动机短舱内流场进行一体化数值模拟,与相应风洞实验数据进行了比较与分析,取得了与实验数据较为吻合的结果.与无发动机短舱的组合体的气动特性进行比较,分析了短舱对翼身组合体的气动干扰. 相似文献
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针对真实情境素材进行分析,提炼实践活动主题,围绕“炼铜厂对环境能否产生污染”这一问题情境设计化学综合实践活动。通过学习炼铜的相关知识,引导学生分析污染产生的原因,了解“三废”的处理方法,培养学生的环保意识;通过学习炼铜的工艺流程,使学生了解实际生产过程的复杂性,培养学生的工程意识。通过角色扮演的职业体验,让学生体会学习化学的重要性,培养学生的参与意识和决策能力。 相似文献
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为解决以往上市公司集成评价模型中各方法评价结果不一致问题,本文构建了改进集成评价模型。该模型先采用层次分析法、灰色关联度法、因子分析法进行评价,并运用KENDALL-W协和系数法对各评价结果进行事前一致性检验;通过检验后,再分别运用算术平均组合评价模型、Borda组合评价模型和Copeland组合评价模型进行组合评价。为了衡量组合评价与各评价方法的评价结果是否吻合,应用Spearman等级相关系数进行组合评价方法的事后检验,并根据Spearman等级相关系数的大小,选出最优的组合评价方法。最后,对中国26家上市运输公司财务绩效进行了集成评价的实证研究,并以算术平均组合评价模型的标准得分为聚类指标,采用欧氏距离法对26家上市运输公司进行聚类。结果显示:铁路、水路、公路运输各存在一个典型绩优企业,分别是:铁龙物流、北京传媒、海峡股份,四类上市运输公司中铁路上市公司财务绩效最优。 相似文献
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为克服传统弹药维修模式下质量检测监控与修理作业分离、检测机构与修理机构分离、军方维修保障力量与民间力量分离的格局,适应高技术弹药维修保障需求,在分析高技术弹药检测与修理技术、检测与修理机构、检测与修理资源等三方面一体化需求的基础上,提出了修理技术、检修力量、维修资源“三维一体”的检修一体化维修模式,构建了通用、专用、辅助3类123种维修设备体系和安全保障、技术方法、业务管理3类52种维修标准体系;对促进传统弹药维修模式的转变,加快高技术弹药维修保障能力的建设具有现实指导作用。 相似文献
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Marion Baillot Gauvin Hemery Olivier Sandre Véronique Schmitt Rénal Backov 《Particle & Particle Systems Characterization》2017,34(10)
A three steps synthesis route is proposed to generate thermosensitive and magnetically responsive γ‐Fe2O3@Wax@SiO2 sub‐micrometer capsules with a paraffinic core and a solid and brittle shell. The process integrates Pickering‐based emulsions, inorganic and sol–gel chemistries to promote monodisperse in size wax droplets, γ‐Fe2O3 nanoparticles and mineralization of the wax/water interfaces. Hybrid capsules are obtained with an average size around 800 nm, representing the first example of sub‐micrometer capsules generated employing Pickering emulsions as templates. Cetyltrimethylammonium bromide (CTAB) cationic surfactant added during mineralization at concentrations between 0.17 and 1.0 wt% impacts the shell density. The shell density seems to improve its mechanical strength while affording a low wax expansion volume without breaking for CTAB concentrations above 1.0 wt%. At lower CTAB concentration (0.17 wt%), the silica shell becomes less bulky and cannot resist the wax dilatation induced by the solid‐to‐liquid phase transition imposed by hyperthermia. The magnetically induced heating provided by the internal magnetic moments is sufficient to melt the wax core, expanding its volume, inducing thereby the surrounding silica shell rupture. Such γ‐Fe2O3@Stearic Acid@Wax@SiO2 sub‐micrometer capsules allow a sustained wax release with time, whereby 20% of the wax is released after 50 min of alternating magnetic field treatment. 相似文献
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With the rapid development of new ‐omics measurement methods, there is an increasing interest in studying the correlation structure between two or more data sets. Multivariate methods such as canonical correlation analysis (CCA) have been proposed to analyze the intrinsic correlation relationship by integrating two data sets. However, because of the high dimensionality of data and the relative scarcity of samples, the ordinary CCA is usually faced with variable selection problems and thereby fails to obtain a satisfactory relationship. Here, we explored the potential of sparse CCA (SCCA) to find the correlative components in two sparse views. SCCA aims at finding sparse projection directions to well extract the correlation between two data sets. We applied this method to one simulation data and one real ‐omics data to illustrate the performance of SCCA. The results from two studies show that SCCA could effectively find the correlated patterns between two data sets, which are of high importance for understanding the relationship between two underlying chemical or biological processes. The corresponding variable subsets selected by sparse weight vectors can assist in a better interpretation of the chemical or biological process. The integrative analysis from two views by SCCA helps in improving the discriminative ability of classification models for various ‐omics studies. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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为提高智能车对多车道的实际道路车辆行驶环境的适应性,提出了一种基于三车道模型的车辆检测方法。方法在预处理的基础上利用极角及位置约束的Hough变换得到可能的车道线信息并利用消失点对车道线进行筛选;利用三车道四线模型对车道线进行匹配;对于每条车道,分别利用车辆灰度信息对车道线内车辆进行识别,并利用视频的连贯性对车辆识别结果进行修正并跟踪车辆。该算法通过对车道线的二次筛选,提高了三车道模型的准确率,进一步提高了对于不同车道车辆识别的正确率。实验结果表明,在结构化道路上,对于不同路况,算法均具有较好的实时性和鲁棒性。 相似文献