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1.
Image and text matching bridges visual and textual modality differences and plays a considerable role in cross-modal retrieval. Much progress has been achieved through semantic representation and alignment. However, the distribution of multimedia data is severely unbalanced and contains many low-frequency occurrences, which are often ignored and cause performance degradation, i.e., the long-tail effect. In this work, we propose a novel rare-aware attention network (RAAN), which explores and exploits textual rare content for tackling the long-tail effect of image and text matching. Specifically, we first design a rare-aware mining module, which contains global prior information construction and rare fragment detector for modeling the characteristic of rare content. Then, the rare attention matching utilizes prior information as attention to guide the representation enhancement of rare content and introduces the rareness representation to strengthen the similarity calculation. Finally, we design prior information loss to optimize the model together with the triplet loss. We perform quantitative and qualitative experiments on two large-scale databases and achieve leading performance. In particular, we conduct 0-shot test for rare content and improve rSum by 21.0 and 41.5 on Flickr30K (155,000 image and text pairs) and MSCOCO (616,435 image and text pairs), demonstrating the effectiveness of the proposed method for the long-tail effect.  相似文献   
2.
文章对美国大学图书馆在信息资源组织与利用方面的创新与实践进行梳理总结,以期为国内图书馆的资源建设提供借鉴。选取美国顶尖的11所大学图书馆作为考察对象,重点介绍它们在馆藏特色文献数据化、资源多样化收集与元数据整合、数字资源全生命周期管理方面的特色和进展。图书馆在资源服务方面所扮演的角色在不断演变,美国大学图书馆正借助先进的信息生产、存储和传递技术,向着实现信息资源共建、共知和共享的目标迈进。国内图书馆需要关注新兴技术,加强特藏资源开发,促进纸质与数字资源融合,优化数字资源业务流程。  相似文献   
3.
采用文献资料法、访谈法等,了解到上海市黄浦区政府培育社会体育组织发展的现状以及存在的问题,提出针对性的发展路径。研究表明:经过阶段性的培育,目前上海市黄浦区社会体育组织结构较完整,规模初现,功能呈现多元化,制度建设日益完善,监督评估机制雏形初显;但培育过程中存在着党建嵌入不足,培育主体较为单一,培育体制机制不完善,培育制度保障体系不健全等问题。提出培育路径:创新党建嵌入方式,实行组织党建工作制度化;搭建组织服务平台,拓宽组织准入范围;分类、分阶段针对性的培育,健全培育体制机制;完善组织制度建设,提升组织服务能力。  相似文献   
4.
本文以可持续发展为视角,阐述了可持续发展视角下全民健身服务体系内涵。利用文献资料法、实地考察法及专家访谈法,对可持续发展视角下全民健身服务体系发展现状进行了简单分析。进一步探究了可持续发展视角下全民健身服务体系建设路径,以期为可持续发展视角下全民健身服务体系建设提供有效的借鉴。  相似文献   
5.
Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus.  相似文献   
6.
Semantic knowledge accumulates through explicit means and productive processes (e.g., analogy). These means work in concert when information explicitly acquired in separate episodes is integrated, and the integrated representation is used to self-derive new knowledge. We tested whether (a) self-derivation through memory integration extends beyond general information to science content, (b) self-derived information is retained, and (c) details of explicit learning episodes are retained. Testing was in second-grade classrooms (children 7–9 years). Children self-derived new knowledge; performance did not differ for general knowledge (Experiment 1) and science curriculum facts (Experiment 2). In Experiment 1, children retained self-derived knowledge over one week. In Experiment 2, children remembered details of the learning episodes that gave rise to self-derived knowledge; performance suggests that memory integration is dependent on explicit prompts. The findings support nomination of self-derivation through memory integration as a model for accumulation of semantic knowledge and inform the processes involved.  相似文献   
7.
[目的/意义] 比较分析语义网技术发展环境下国外代表性知识组织体系管理工具的研究现状及关键功能,梳理相关研究的发展趋势。[方法/过程] 通过网络调研法,遴选国外10个代表性知识组织体系管理工具,从结构定义、项目维护、数据管理、互操作性、操作环境等方面比较分析其发展现状。在此基础上,为国内知识组织体系管理工具的建设工作提供建议。[结果/结论] 研究发现,国内知识组织体系管理工具的建设工作应依托语义网、关联数据、语义集成、语义互操作等技术促进功能创新,包括:灵活设计并配置多类型数据模型、支持可持续发展的管理与维护机制、支持用户分布式协同管理与控制、知识驱动的数据迭代式更新、面向语义的KOS重用与进化、建设以KOS为核心的知识组织框架等。  相似文献   
8.
运用文献资料法,并以协同学理论为研究工具,研究分析了现代体育教学的发展,同时找出现代体育教学发展的促进因子。研究认为:在子系统之间,体育教学发展的内在动力是“协同”和“竞争”,体育教学组织系统与外界因素的“协同”与“竞争”是其发展的外在推动力,序参量的“协同”与“竞争”是其发展的核心动力。  相似文献   
9.
The proposed work aims to explore and compare the potency of syntactic-semantic based linguistic structures in plagiarism detection using natural language processing techniques. The current work explores linguistic features, viz., part of speech tags, chunks and semantic roles in detecting plagiarized fragments and utilizes a combined syntactic-semantic similarity metric, which extracts the semantic concepts from WordNet lexical database. The linguistic information is utilized for effective pre-processing and for availing semantically relevant comparisons. Another major contribution is the analysis of the proposed approach on plagiarism cases of various complexity levels. The impact of plagiarism types and complexity levels, upon the features extracted is analyzed and discussed. Further, unlike the existing systems, which were evaluated on some limited data sets, the proposed approach is evaluated on a larger scale using the plagiarism corpus provided by PAN1 competition from 2009 to 2014. The approach presented considerable improvement in comparison with the top-ranked systems of the respective years. The evaluation and analysis with various cases of plagiarism also reflected the supremacy of deeper linguistic features for identifying manually plagiarized data.  相似文献   
10.
网络化管理模式的发展引起的管理创新   总被引:2,自引:0,他引:2  
以网络经济为时代背景,通过分析网络技术和信息技术对管理的影响,提出了管理创新的新思想-网络化管理,并在此基础上详细论述了网络化与管理在理念,组织结构,手段和文化四个领域的创新。文章对研究新经济条件下的管理创新具有一定的指导意义。  相似文献   
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