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41.
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。  相似文献   
42.
[目的/意义]介绍Make Data Count与COUNTER联合推出的《研究数据使用统计实施规范》,为数据级别计量提供新指标与新视角。[方法/过程]通过对标准文本的分析,介绍该规范的提出背景、目标、范围、相关概念及核心内容,通过案例剖析Dash、DataONE、Zenodo及其他7个数据存储库对《规范》的应用情况。[结果/结论]研究数据的使用统计具有其独特之处,《规范》的推出可对数据引用及数据替代计量形成补充进而描述完整的科研学术影响力。目前遵循该规范的数据存储库还不多,为推动数据使用计量的应用,需要标准组织、科研人员、机构库及数据存储库、出版商、科研机构及资助机构、图书馆等不同利益相关者在数据产生、管理、传播与利用等环节的相互合作。  相似文献   
43.
丁文姚  李健  韩毅 《图书情报工作》2019,63(22):118-128
[目的/意义] 探索期刊论文科学数据引用特征与规律不仅有助于描述学科领域对科学数据的利用情况,还能够揭示学术成果表达中的数据引用模式。[方法/过程] 以我国图书情报领域6种期刊2017年与2018年第一期刊载论文为样本,结合国家标准《信息技术科学数据引用》的引用元素,采用内容分析法从9个维度对样本论文的科学数据引用行为进行数据编码,应用统计学方法描述图书情报领域期刊论文科学数据引用特征并探索不同维度特征间的关联关系。[结果/结论] 图书情报领域期刊论文广泛引用来自国内外的统计整理类科学数据,对期刊论文中个人研究科学数据的引用量较大;科学数据引用标注方式与科学数据类型存在一定对应关系,但多样化的标注方式缺乏统一性;二手引用现象较为突出,二手引用程度与科学数据创建者类型相关。  相似文献   
44.
In recent years, strategies focused on data-driven innovation (DDI) have led to the emergence and development of new products and business models in the digital market. However, these advances have given rise to the development of sophisticated strategies for data management, predicting user behavior, or analyzing their actions. Accordingly, the large-scale analysis of user-generated data (UGD) has led to the emergence of user privacy concerns about how companies manage user data. Although there are some studies on data security, privacy protection, and data-driven strategies, a systematic review on the subject that would focus on both UGD and DDI as main concepts is lacking. Therefore, the present study aims to provide a comprehensive understanding of the main challenges related to user privacy that affect DDI. The methodology used in the present study unfolds in the following three phases; (i) a systematic literature review (SLR); (ii) in-depth interviews framed in the perspectives of UGD and DDI on user privacy concerns, and finally, (iii) topic-modeling using a Latent Dirichlet allocation (LDA) model to extract insights related to the object of study. Based on the results, we identify 14 topics related to the study of DDI and UGD strategies. In addition, 14 future research questions and 7 research propositions are presented that should be consider for the study of UGD, DDI and user privacy in digital markets. The paper concludes with an important discussion regarding the role of user privacy in DDI in digital markets.  相似文献   
45.
Firms are increasingly relying on business insights obtained by deploying data analytics. Analytics-driven business decisions have thus taken a strategic imperative role for the competitive advantage of a firm to endure. The extent and effectiveness through which business firms can actually derive benefits by deploying big data-based practices requires deep analysis and calls for extensive research. This study extends the big data analytics capability (BDAC) model by examining the mediatory effects of organizational culture (CL) between internal analytical knowledge (KN) and BDAC, as well as the mediating effects of BDAC between CL and firm performance. The findings bring into focus that CL plays the role of complementary mediation between BDAC and KN to positively impact firm performance (FP); BDAC also plays a similar mediatory role between CL and the performance of a firm.  相似文献   
46.
[目的/意义] 梳理人文社科专著众筹OA出版的发展现状,分析具有公益性特点的OA出版物和具有商业性特点的众筹出版所引起的冲突,以期对学术专著众筹出版提出有价值的思考。[方法/过程] 从发起者、投资者和众筹平台3个基本要素梳理Open Book Publishers和Knowledge Unlatched的众筹模式,比较异同点,探讨两者在竞争中引起的问题。[结果/结论] 目前,欧美国家的学术专著众筹出版分为高校、众筹商和OA出版社3种模式。Knowledge Unlatched是期望通过对图书馆的优质服务获得收益的众筹商,Open Book Publishers是借助网络开展众筹出版的OA出版社,两者属于商业化大型公司和非营利性OA出版社的竞争关系,在OA出版物的商业化开发、财务公开透明、垄断性的销售模式和审核制度方面值得高度关注。  相似文献   
47.
ABSTRACT

This study aimed to assess which combination of subjective and empirical data might help to identify the expertise level. A group of 10 expert coaches classified 40 participants in 5 different expertise groups based on the video footage of the rallies. The expertise levels were determined using a typology based on a continuum of 5 conative stages: (1) structural, (2) functional, (3) technical, (4) contextual, and (5) expertise. The video allowed empirical measurement of the duration of the rallies, and tri-axial accelerometers measured the intensity of the player’s involvement. A principal component analysis showed that two dimensions explained 54.9% of the total variance in the data and that conative stage and empirical parameters during rallies (duration, intensity of the game) were correlated with axis 1, whereas duration and acceleration data between rallies were correlated with axis 2. A random forest algorithm showed that among the parameters considered, acceleration, duration of the rallies, and time between rallies could predict conative stages with a prediction accuracy above possibility.

This study suggests that performance analysis benefits from the confrontation of subjective and objective data in order to design training plans according to the expertise level of the participants.  相似文献   
48.
Technical difficulties occasionally lead to missing item scores and hence to incomplete data on computerized tests. It is not straightforward to report scores to the examinees whose data are incomplete due to technical difficulties. Such reporting essentially involves imputation of missing scores. In this paper, a simulation study based on data from three educational tests is used to compare the performances of six approaches for imputation of missing scores. One of the approaches, based on data mining, is the first application of its kind to the problem of imputation of missing data. The approach based on data mining and a multiple imputation approach based on chained equations led to the most accurate imputation of missing scores, and hence to most accurate score reporting. A simple approach based on linear regression performed the next best overall. Several recommendations are made regarding the reporting of scores to examinees with incomplete data.  相似文献   
49.
数据结构是高等院校计算机专业的一门重要的专业课。就目前普遍采用的面向过程的教学方式的弊端,提出了进行对象化的教学方式。结合我院实践,提出了一系列的教学步骤,并对此作了分析和探讨。  相似文献   
50.
数据同步技术随着企业对各个信息系统之间数据共享的重视而变得越来越重要,数据同步的方法有很多,本文主要介绍基于ETL技术和基于全表扫描及哈希对比两种数据同步方法。基于ETL技术的数据同步是基于中间逻辑表完成数据转换,再通过主键和时间戳的对比而完成数据同步过程。本文以Kettle工具为例进行分析;基于全表扫描及哈希对比的数据同步是基于视图完成数据转换,再通过hash算法扫描对比而完成数据同步过程。  相似文献   
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