基于小型无人直升机的三维建模成像系统设计     

张谦  裴海龙 《广东教育学院学报》2014,(3):68-74

对于大角度、大范围、复杂场景的快速扫描成像系统,除了要进行任意运动和动态采集建模外,还要对激光传感器的姿态和位置进行实时精确的描述.基于此要求,文中构建了一种基于小型无人直升机机载激光扫描传感器的三维建模成像系统,并设计了一种分步式串级滤波算法,将激光测距传感器得到的距离信息,与小型无人直升机惯性导航系统解算的姿态与位置数据进行融合,实现空间扫描点到基准坐标系的映射,并完成2D行扫描到3D空间的扩展,建立现实世界的3D数字模型.  相似文献   

基于协同过滤的个性化推荐选课系统研究     

徐天伟  宋雅婷  段崇江 《现代教育技术》2014,(6):92-98

针对高等学校学生选课系统中存在的缺乏个性化课程推荐、选课效率不高的问题,通过对个性化推荐技术的分析研究,提出了基于项目、用户及属性值矩阵的协同过滤算法,并把该算法应用到选课系统中,数据表明,算法解决了个性化推荐技术中的冷启动问题,相关指标有明显提高,实现了课程的个性化推荐和新课程的推荐。  相似文献   

An approach to web-based Personal Health Records filtering using fuzzy prototypes and data quality criteria     

Francisco P. Romero  Ismael CaballeroJesus Serrano-Guerrero  Jose A. Olivas 《Information processing & management》2012

Nowadays, new ways of managing and accessing to health-care information are continuously appearing. Web-based Personal Health Records (web PHRs) have the potential to make data about health-care available to clinicians, researchers and students in different medical contexts and applications. Therefore, the amount of web PHRs accessible through Internet has grown enormously and as a result health-care professionals are currently burdened with more and more data. It’s probable that these data, unfortunately, have not always the adequate levels of quality, making that their work cannot always be as successful as expected. As a way of alleviating this fact, the present work is focused on improving the document filtering results in the context of web PHRs management. To achieve this goal, a new kind of document filtering model is proposed. This model is based on fuzzy prototypes which are defined by means of conceptual prototypes. These prototypes are obtained by using a data quality analysis of documents. This analysis guarantees that filtered information will be relevant enough for the information user. The complete model provides an efficient strategy of document filtering that can be very useful when it is necessary to deal with a constant flow of new information.  相似文献   

A collaborative filtering similarity measure based on singularities     

Jesús Bobadilla  Fernando OrtegaAntonio Hernando 《Information processing & management》2012

Recommender systems play an important role in reducing the negative impact of information overload on those websites where users have the possibility of voting for their preferences on items. The most normal technique for dealing with the recommendation mechanism is to use collaborative filtering, in which it is essential to discover the most similar users to whom you desire to make recommendations. The hypothesis of this paper is that the results obtained by applying traditional similarities measures can be improved by taking contextual information, drawn from the entire body of users, and using it to calculate the singularity which exists, for each item, in the votes cast by each pair of users that you wish to compare. As such, the greater the measure of singularity result between the votes cast by two given users, the greater the impact this will have on the similarity. The results, tested on the Movielens, Netflix and FilmAffinity databases, corroborate the excellent behaviour of the singularity measure proposed.  相似文献   

Enhancement of information seeking using an information needs radar model     

Cho-Wei Shih  Ming-Yen Chen  Hui-Chuan Chu  Yuh-Min Chen 《Information processing & management》2012

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适应用户兴趣变化的协同过滤增量更新机制   总被引：1，自引：0，他引：1  

李聪  梁昌勇 《情报学报》2010,29(1)

高维、稀疏的用户-项目评分矩阵对基于项目的协同过滤推荐算法造成严峻的可扩展性问题.传统的解决方法是离线计算项目相似性并保存在系统中以供算法调用,但是不能充分利用最新评分数据以体现用户兴趣的变化.针对上述问题,提出了适合在线应用的协同过滤项目相似性增量更新机制,使得推荐系统在当前用户提交项目评分之后,能够实时完成相应项目与其他项目之间的相似性数据更新,从而推荐系统可以基于最新的项目相似性数据进行推荐处理,以适应用户兴趣的变化.实验结果表明,本文提出的项目相似性增量更新机制能够有效提高基于项目的协同过滤算法可扩展性.  相似文献   

Δ-distance: A family of dissimilarity metrics between images represented by multi-level feature vectors     

Marta Rukoz  Maude Manouvrier  Geneviève Jomier 《Information Retrieval》2006,9(6):633-655

This article presents the Δ-distance, a family of distances between images recursively decomposed into segments and represented by multi-level feature vectors. Such a structure is a quad, a quin or a nona-tree resulting from a fixed and arbitrary image partition or from an image segmentation process. It handles positional information of image features (e.g. color, texture or shape). Δ-distance is the generalized form of dissimilarity measures between multi-level feature vectors. Using different weights on tree nodes and different distances between nodes, distances between trees or visual similarity between images can be computed based on the general definition of Δ. In this article, we present three Δ-based distance families: two families of distances between tree structures, called -distance( for Tree) and -distance ( for Segment), and a family of visual distances between images, called ( for Visual). The -distance visually compares two images using their tree representation and the other two distances compare the tree structures resulting from image segmentation. Moreover, we show how existing distances between multi-level feature vectors appear to be particular cases of the Δ-distance  相似文献   

基于聚类协同过滤的个性化推荐系统     

程淑玉 《宜宾师范高等专科学校学报》2013,(6):82-85

个性化推荐系统被越来越多地应用到各类网站中,以解决信息增长带来的信息迷失和信息过栽问题,而协同过滤算法是个性化推荐系统的重要算法之一,但是传统的协同过滤算法存在数据稀疏、冷启动等问题,为了解决这些问题,在综合WEB日志挖掘和聚类两个因素基础上,提出基于WEB日志和聚类的协同过滤算法,并将该算法与传统的协同过滤算法进行分析比较,验证了该算法能够提高推荐的精确度和实时性．  相似文献   

Social network data to alleviate cold-start in recommender system: A systematic review     

Lesly Alejandra Gonzalez Camacho  Solange Nice Alves-Souza 《Information processing & management》2018,54(4):529-544

Recommender Systems are currently highly relevant for helping users deal with the information overload they suffer from the large volume of data on the web, and automatically suggest the most appropriate items that meet users needs. However, in cases in which a user is new to Recommender System, the system cannot recommend items that are relevant to her/him because of lack of previous information about the user and/or the user-item rating history that helps to determine the users preferences. This problem is known as cold-start, which remains open because it does not have a final solution. Social networks have been employed as a good source of information to determine users preferences to mitigate the cold-start problem. This paper presents the results of a Systematic Literature Review on Collaborative Filtering-based Recommender System that uses social network data to mitigate the cold-start problem. This Systematic Literature Review compiled the papers published between 2011–2017, to select the most recent studies in the area. Each selected paper was evaluated and classified according to the depth which social networks used to mitigate the cold-start problem. The final results show that there are several publications that use the information of the social networks within the Recommender System; however, few research papers currently use this data to mitigate the cold-start problem.  相似文献   

Nearest-biclusters collaborative filtering based on constant and coherent values     

Panagiotis Symeonidis  Alexandros Nanopoulos  Apostolos N. Papadopoulos  Yannis Manolopoulos 《Information Retrieval》2008,11(1):51-75

Collaborative Filtering (CF) Systems have been studied extensively for more than a decade to confront the “information overload” problem. Nearest-neighbor CF is based either on similarities between users or between items, to form a neighborhood of users or items, respectively. Recent research has tried to combine the two aforementioned approaches to improve effectiveness. Traditional clustering approaches (k-means or hierarchical clustering) has been also used to speed up the recommendation process. In this paper, we use biclustering to disclose this duality between users and items, by grouping them in both dimensions simultaneously. We propose a novel nearest-biclusters algorithm, which uses a new similarity measure that achieves partial matching of users’ preferences. We apply nearest-biclusters in combination with two different types of biclustering algorithms—Bimax and xMotif—for constant and coherent biclustering, respectively. Extensive performance evaluation results in three real-life data sets are provided, which show that the proposed method improves substantially the performance of the CF process.

Yannis ManolopoulosEmail:

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