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Search Results: 1 - 10 of 7354 matches for " 时晶晶 "
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高速倾斜镜建模与传递函数辨识
晶晶,姚佰栋,鲁加国
红外与激光工程 , 2013,
Abstract: 为了在光束稳定控制系统中更好地对高速倾斜镜(FSM)实现稳定、精确地控制,对于由超磁致伸缩材料(GMM)作为位移产生元件的高速倾斜镜,根据GMM材料的特性和倾斜镜的运动机理,经推导建立了倾斜镜的传递函数模型,并结合实测的倾斜镜幅频和相频响应特性,在Matlab软件中利用Levy法对倾斜镜的传递函数进行了辨识,得到了精确的倾斜镜传递函数。与实测结果相比,在中低频段,幅度辨识误差在0.3dB以内,相位辨识误差在5°以内,结果表明:通过理论推导建立的倾斜镜模型是合理有效的,对于改善该倾斜镜在应用系统中的稳定性和精度提供了依据。
基于管线对偶图模型的供水管网可靠性分析
曾文,圣磊,晶晶
- , 2018, DOI: 10.11918/j.issn.0367-6234.201707192
Abstract: 为了利用复杂网络理论对供水管网进行结构测度和鲁棒性分析,提出一个新的管网模型——管线对偶图模型.该模型将顺序相连、无大角度转折的同口径同材质管段序列看作统一实体,即管线.将管线抽象为节点,两相交管线对应的节点用边相连,由此形成的无向图即为管线对偶图.使用这一模型对3个城市的供水管网进行结构测度,结果显示,管线对偶图具有明显的无标度特性.利用无标度网络鲁棒性分析方法中的模拟攻击方法,使用3种攻击策略进行实验.结果表明,管网在不同攻击策略下结构变化规律呈现较强的相似性,都会经过初始期、分裂期和崩溃期3个阶段;不同的攻击策略下供水管网进入分裂期和崩溃期的进程差异明显;基于节点度的攻击策略对管网的影响最大,基于节点介数中心性其次,随机攻击对管网的影响最小,高度连接的管线是供水管网中关键和脆弱的部分.对结构测度和模拟攻击的结果进行分析,发现谱隙和进入分裂期的去点率可作为衡量供水管网可靠性的重要指标.针对管线对偶图模型提出的可靠性分析方法可以用于指导供水管网的设计和运维.
A novel water supply network model, pipeline dual graph (PDG), is proposed for structure measurement and robustness analysis of water supply networks using complex network theory. If water pipes of same diameter and material are sequentially connected in rather small angle changes, this model takes them as a unified entity called pipeline. A PDG is an undirected graph constructed by taking every pipeline as a node and inserting a link between two nodes corresponding to a couple of intersected pipelines. Structure measurement for 3 Chinese cities' water supply networks shows that pipeline dual graphs are scale-free networks. Attack simulations using 3 strategies based on scale-free network robustness analysis methods were designed and conducted. Experimental results indicated that structural change processes of these networks were similar under different attack strategies, which all consisted of the initial phase, the splitting phase and the collapsing phase. However, every network entered the splitting phase and the collapsing phase at a distinctly different speed. Among the 3 strategies, the strategy based on node degree had the greatest impact on water supply networks, followed by the strategy based on betweenness, while random attacks had the least influence. Highly connected pipelines are critical and vulnerable components. Structure measurement and attack simulations prove that spectral gap and node removal rate while entering the splitting phase can be adopted as important indicators for evaluating the reliability of water supply networks. The proposed reliability analysis method based on PDG model can be used to guide design and operation of water supply networks.
汽车运动状态在线测量及预报技术
刘军,晶晶,枭鹏,何国国
中国公路学报 , 2011,
Abstract: ?为了有效地对汽车自身可能的运动状态进行预报,并对潜在的行车危险进行预警,开展了汽车运动状态在线测量及预报技术研究。设计了微惯性测量单元,实现汽车运动状态参数在线测量,介绍了汽车姿态解算及其速度积分算法;设计了Kalman滤波器,通过信号融合处理获取汽车运动状态参数的最优估计值;阐述了自回归建模预报方法,并开发了汽车运动状态在线测量及预报软件;最后搭建了车载试验平台并进行了实车道路试验。结果表明:汽车运动状态在线测量及预报技术具有很好的预报效果,为未来开发性能更可靠、效果更佳的汽车主动安全预警系统提供了一定的理论依据和技术途径。
西方儿童秘密的研究回顾
The Study Review of Children’s Secret in Western Country
 [PDF]

晶晶
Advances in Psychology (AP) , 2015, DOI: 10.12677/AP.2015.52016
Abstract:
近几十年来,儿童的秘密对于儿童成长的影响受到众多研究者的关注。心理学和教育学领域的许多研究者进行了大量有关从学前期儿童到青少年儿童秘密的研究。秘密不仅指那些藏在我们内心深处的,也可指那些我们只愿意与某些人分享的事件和感受,其在儿童成长中具有重要的影响和作用。文章从儿童秘密的产生、发展、研究方法以及研究现状对现有研究进行了综述,并对未来的研究进行了展望。
In recent decades, researchers have been interested in the influence of secret on children’s growth. Researches in areas of psychology and pedagogy have already conducted large amounts of re-searches concerning the influence of secret on preschool children and adolescents. The definition of “secret” does not only refer to things hidden inside but also those they only want to share with a few people. Secret plays an important role in children growth. The article reviewed the origin, de-velopment, and study method, research situation of children’s secret, and prospected the orienta-tion for future research.
四丁基氯化铵水合物的蓄冷特性
谢应明,晶晶,刘道平,竞竞,刘妮,祁影霞
化工学报 , 2010,
Abstract: 探讨了一种新型季铵盐——四丁基氯化铵的水合物作为蓄冷工质的可行性,对其蓄冷特性进行了实验研究:研究了溶液浓度、循环次数及添加成核剂硼砂对四丁基氯化铵水合物的生长特性的影响。实验结果表明:浓度为40%的TBAC溶液相变过程相对稳定,更适合空调蓄冷工况;添加成核剂硼砂使TBAC溶液的相变温度降低了2℃,结晶过冷度减小2℃;经过多次重复水合反应后,溶液在结晶过程中的过冷度减小了1.5℃,相变温度无变化。利用DSC测试得到四丁基氯化铵水合物相变温度为10.41℃,相变潜热为197.707J·g-1。
基于超磁致伸缩材料的高速倾斜镜的设计与应用
姚佰栋,晶晶,侯再红,谭逢富,吴毅
红外与激光工程 , 2013,
Abstract: 在目标跟踪系统中,由于大气湍流的影响导致光波振幅和相位起伏。为了提高跟踪性能,降低大气湍流造成的光斑倾斜成为了首要目标,而高速倾斜镜(FSM)则是达成这一目标的关键器件。文中介绍的高速倾斜镜利用超磁致伸缩材料(GMM)作为位移驱动元件,通过线圈的电流产生磁场控制材料的伸缩,从而驱动倾斜镜的偏转。该倾斜镜已经被应用于激光大气传输倾斜校正系统中,使湍流造成的倾斜减少了90%,光斑稳定度和光斑质量得到了明显提高。
石墨纳米片对铜电子浆料导电性的影响
晶晶,屈银虎,成小乐,周宗团,符寒光,祁志旭
- , 2018, DOI: 10.11951/j.issn.1005-0299.20170137
Abstract: 为改善铜浆导电性,以表面改性的金属铜粉为主要导电相,通过添加少量导电性优异的石墨纳米片作为导电增强相制备复合电子浆料,并采用四探针测试仪、扫描电子显微镜(SEM)等分析测试方法研究了石墨纳米片的参数、添加量对铜电子浆料导电性能的影响.结果表明:选用厚度为3~5 nm,片径为5 μm的石墨纳米片作为导电增强相,制得石墨纳米片—铜电子浆料,在460 ℃烧结后导电膜层的电阻率较小;石墨纳米片与铜粉质量比为2:98时,测得浆料电阻率为17.14 mΩ·cm,相比纯铜浆料电阻率34.43 mΩ·cm降低了50.22%.分析电子浆料导电机理并建立导电相连接几何模型,在导电膜层中,部分折断的石墨纳米片会填充到铜颗粒之间的空隙中,较长石墨纳米片则会形成“搭桥”现象,增加导电相之间的连接,形成较紧密的微观组织和良好的导电网络,从而改善复合浆料的导电性.
To improve the conductivity of the copper pastes, the surface-treated copper powders were used as the main conductive phases, and a small amount of graphene flakes was used as the conductive reinforced phases to prepare the composite electronic pastes. The effect of the specifications and additions of graphene flakes on conductivity were characterized by four-point probe, scanning electron microscopy (SEM) and other testing methods. The results show the pastes with the graphene flakes with a thickness of 3~5 nm and a flake size of 5 μm has a smaller resistivity after sintered at 460 ℃. When the mass ratio of graphene flakes and copper powders is 2.98, the resistivity of the pastes is measured to be 17.14 mΩ·cm, 50.22% lower than that of the copper pastes (34.43 mΩ·cm). The conductive mechanism of the electronic pastes is revealed and geometric model of connection of the conductive phases is established. In the conductive film, the gaps between copper powders are filled by the broken graphene flakes and bridges are jointed between copper powders by longer graphenehe flakes, causing the formation of a compact microstructure and excellent conductive network. Thus the conductivity of the pastes is dramatically improved.
RSNA2014中枢神经系统影像学
晶晶,,王剑,申楠茜,朱文杰,苏昌亮
- , 2015, DOI: 10.13609/j.cnki.1000-0313.2015.02.001
Abstract: 【摘要】RSNA2014报道的拓展MRI新技术及数据分析方法主要包括非高斯分布扩散成像模型(FROC模型)、扩散峰度成像(DKI)、酰胺质子转移成像(APT)、高分辨率敏感加权成像(HR-SWI)、化学交换饱和转移(CEST)、高分辨率磁共振成像(HRMRI)、反相-对比结合磁共振血管成像(HOP-MRA)、反转恢复超短回波时间(IR-UTE)序列等,在中枢神经系统疾病的应用研究主要包括:①鉴别高低级别胶质瘤、预测胶质瘤复发以及评价胶质瘤治疗反应;②检测缺血性卒中随时间变化特点、评估缺血半暗带、预测侧支循环及血管再通状态;③磁共振高分辨率血管壁成像观察颅内动脉粥样硬化血管壁的异常;④量化评估阿尔茨海默病脑部微结构损害、阿尔茨海默病病理性铁沉积定量;⑤证实帕金森病特定脑区损害、辅助帕金森病分子水平诊断;⑥糖尿病脑损伤的认知功能以及精神疾病功能成像
一种基于企业级云的云模式构架
A Cloud Computer Architecture Based on Enterprises Cloud
 [PDF]


Computer Science and Application (CSA) , 2012, DOI: 10.12677/CSA.2012.24033
Abstract: 本文提出了一种基于企业级云的云模式构架,目的是为了提出一个适合企业需求的云平台方案。通过对企业级云模式概念的描述、对其难点与关键技术的分析及流程图构建与系统功能分析,给出了该模式的应用框架。
This paper presents a cloud computer architecture based on enterprises cloud. The architecture is suitable for the requirements of the enterprises. Its application framework of is elaborated by description of enterprises cloud notation, analysis of the difficulties and critical technologies, construction of flow chart, and system functional analysis.
微胶囊铜粉对铜复合浆料性能的影响
晶晶,屈银虎,成小乐,祁志旭,刘晓妮,周思君,祁攀虎,周宗团
- , 2017, DOI: 10.11951/j.issn.1005-0299.20170021
Abstract: 为提高铜浆料的导电性,利用微胶囊技术在铜粉表面包覆液体石蜡,增强铜粉的抗氧化性,并添加少量导电性能优异的碳纳米管作为导电增强相,制备碳纳米管-铜复合浆料.利用四探针测试仪、扫描电镜等测试方法研究了液体石蜡含量对包覆铜粉性能的影响以及微胶囊铜粉作为主导电相,碳纳米管作为导电增强相对浆料导电性能的影响.结果表明:液体石蜡包覆含量为4 wt%的微胶囊铜粉具有良好的导电性和抗氧化性,其电导率为44.32%IACS;微胶囊铜粉作为碳纳米管-铜浆料的主导电相,制备浆料膜层电阻率为22.59 mΩ·cm,相比于未包覆的铜粉为主导电相制备的浆料膜层电阻率降低了12.44%;碳纳米管作为导电增强相所制备的浆料相比于纯铜浆料,电阻率降低31.74%.
The copper powders were coated with liquid paraffin by micro capsule technology to enhance the antioxidation of copper powders. A small amount of carbon nanotubes with good conductivity were added as conductive reinforced phase to prepare the composite paste. Influences of paraffin content on the paraffin-coated copper powders were analyzed. Influences of micro capsule copper powders as main conductive phase and carbon nanotubes as conductive reinforced phase were characterized by Four-Point probe, scanning electron microscopy(SEM) and other testing methods. The results show that copper powders coated by 4 wt% paraffin have better conductive property and oxidation resistance. Its conductivity is 44.32 s/cm. The micro capsule copper powders are used as conductive phase to prepare the paste. Its resistivity is 22.59 Ω·cm, which is decreased by 12.44% compared to the copper paste. The resistivity of the paste with carbon nanotubes as conductive reinforced phase is decreased by 31.74% compared to the copper paste.
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