基于读者行为追踪的智能服务研究——以帆布指纹识别与CNZZ为例

[目的/意义]高校图书馆为了掌握读者信息需求动态数据。[方法/过程]利用帆布指纹识别与CNZZ两种方法进行读者信息追踪,获取读者信息行为,在法律与道德允许范围内,从获取的数据中挖掘读者需求信息。通过对高校读者的信息行为的特征需求分析,匹配与图书馆拥有的信息资源并通过网络平台推送至读者。[结果/结论]借助于智能推荐系统,能够促进服务由粗放化向精细化转变,用以提高图书馆智能化服务水平。     

损失规避下的指数跟踪问题及其粒子群算法求解

随着指数衍生产品日益受到重视,指数化投资组合常被传统的消极基金管理者或机构所采用,而用有限的资金按指数构成比例进行投资显然是不现实的,所以指数的最优误差追踪就显得更加重要。将追踪误差定义为证券投资组合收益率与所追踪的指数基准收益率之差的均值平方和的平方根,建立了基数约束（即总资产数不超过某个特定整数K）下考虑投资者损失规避决策偏好的跟踪误差最小化模型,并设计了一个粒子群算法求解模型。实际算例表明,所构建的模型和算法是有效的。     

自动跟踪补偿消弧线圈在配电网中的选用

目前,我国城市配电网中电力电缆的应用愈来愈广泛,系统电容电流越来越大,在发生单相接地时电弧不能熄灭,会造成电弧间歇性的熄灭与重燃,形成弧光接地电压或激发磁谐振危及电气设备绝缘,严重时有可能发展为相间短路,引起事故。为限制单相接地故障电流,6-35KV系统采用中性点通过消弧线圈接地来补偿单相接地时的电容电流使电弧熄灭,限制弧光接地过电压和消除铁磁谐振过电压,现已取得较多的运行经验和较好运行效果。     

物料跟踪系统在步进式加热炉上的应用

以河北唐银钢铁有限公司棒材、高线两条轧钢生产线的步进式加热炉实现物料跟踪的全过程为例,论述了步进式加热炉物料跟踪的理念、跟踪的实现过程,重点分析了实现加热炉钢坯物料跟踪的方法和影响跟踪过程准确的几个关键要素:包括装钢定位、步距调整、有钢判断、位置跟踪、炉号跟踪等.提出准确是物料跟踪的核心,实现跟踪准确的前提是控制好炉底...     

终端滑模控制器设计在永磁同步电动机中的应用

文中考虑了一类永磁同步电动机的终端滑模控制器设计问题.在控制器设计中利用中继切换控制使系统在给定的当前控制律的作用下运行到某一特定状态（或某一特定区域）后,控制律被切换到有限时间收敛的终端滑模控制器,使得系统在有限时间内达到平衡状态.终端滑模控制器的设计保证了闭环系统所有信号的有界性和平衡点的全局稳定性,以及系统在有限时间内精确地跟踪给定的参考信号.最后,通过一个数值仿真验证了所提算法的正确有效性.     

From care to education and work? Education and employment trajectories in early adulthood by children in out-of-home care

BackgroundTemporal dynamics during the early adulthood transition among children in out-of-home care is a neglected research area, leaving the possibility of coping with childhood adversity over time a poorly understood topic.ObjectiveTo explore early adulthood education and employment trajectories among young adults who experienced out-of-home care during childhood and to examine how various care history factors predict these trajectories.ParticipantsWe use longitudinal birth cohort data comprising individual-level information from national registers of all children born in Finland in 1987 (N = 59,476, of whom 1893 were in care).Setting and methodsWe use trajectory clustering from a previous study on the 1987 birth cohort to compare trajectories between children in care and a propensity score–matched group of peers never in care. We investigated the association between care history factors and trajectories with multinomial logistic regression modeling.ResultsCompared with the matched peer group, children in care were less likely to enter trajectories characterized by education and employment (38%) and more likely to enter trajectories involving early parenthood (14%) or long periods of fragmented social assistance benefit receipt and unemployment (21%). Those on early parenthood trajectories were almost exclusively women, whereas those receiving social assistance benefits and experiencing unemployment for lengthy periods were mostly men. Entering disadvantaged trajectories was associated with, inter alia, placement as an adolescent, residential care, and aging out of care.ConclusionThe study demonstrates the relevance of examining longitudinal trajectories in children in care’s early adulthood. Many young adults with care experience need support in education and employment beyond young adult age.     

风向跟踪风力发电教学实训装置的设计

主要是根据风力发电的原理、组成和运行过程,提出风向跟踪风力发电教学实训设备的设计方案,为高职院校风电类实训设备的开发提供参考.     

The integration of information in a digital,multi-modal learning environment

The aim of the reported eye-tracking study was to investigate whether learners integrate information presented on several pages within a digital learning environment and whether the underlying processes differ between a purely text-based and a multi-modal digital learning environment. Participants (N = 97) learned about the development of tornados. Picture presentation (yes vs. no) and presentation of inconsistent information between pages (yes vs. no) was varied between-subjects. Results showed that inconsistent information led to more intense gaze behavior. This indicates that learners re-activated information presented on previous pages to integrate it with the actual information, enabling them to detect the inconsistencies. Furthermore, the data pattern for text-related gaze behavior was not influenced by picture presentation, indicating that cognitive processes in purely text based or multi-modal learning environments are much the same. Comprehension outcomes did not differ between groups. The implications of these results are discussed.     

基于协同表示的目标跟踪算法

提出一种基于协同表示的新的目标跟踪算法.在贝叶斯框架下,采用基于重构误差的观测似然函数和考虑遮挡的模型更新机制设计一个鲁棒的跟踪器.用l₁范数来建模重构误差以更好地容忍奇异值,同时用协同表示对编码系数进行约束.实验结果表明,和其他算法相比,本文算法能够战胜遮挡、尺度变化、光照变化、背景混乱等干扰因素,具有较高的准确度和鲁棒性.     

一种在轨海上多运动舰船目标检测和跟踪方法

传统遥感卫星图像处理采用在地面进行目标检测和跟踪处理的模式,卫星将拍摄到的图像数据下传至地面数据处理中心,由地面数据处理系统对接收到的遥感图像数据进行目标检测和跟踪。然而,随着遥感图像分辨率的不断提高,需要下传的数据量增大,导致星地数据传输的时间大大增加,最终造成目标检测和跟踪的时效性降低。针对上述问题,提出一种基于多特征量判别的Canny边缘检测和联合概率数据关联的在轨海上多运动舰船目标检测和跟踪方法。将该方法利用中国科学院微小卫星创新研究院的高分微纳卫星实测数据在模拟星载的嵌入式开发平台上进行验证,结果表明该方法能够在轨对海上多运动舰船目标进行快速、准确的检测和跟踪。