教科書LODは，国立教育政策研究所教育図書館や教科書研究センター附属教科書図書館が長年かけて組織化してきた書誌情報をまとめてLOD化したものである。1992年施行の学習指導要領以降の検定教科書を対象として，書誌事項と教科等の関連情報をLOD化し，2018年3月現在，7,257タイトルの教科書情報，RDFデータとして157,297トリプルを公開している。本稿では教科書LODの開発および公開を通して得た知見を紹介する。

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Toward the interoperability and scalability in smart city applications, we propose a water level measurement system based on RESTful accesses and AWS-based cloud services. In this paper, we demonstrate the feasibility of the proposed method using an implemented device with an ultrasonic sensor on a Raspberry Pi. The measured water level data are stored in the AWS Dynamo database, and each data is assigned a unique URI; thus, we can access the data via an HTTP/GET message. Moreover, when the water level exceeds the reference value, the proposed system sends a notification via email.

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We introduce the features of Common Agriculture Vocabulary (CAVOC) and CAVOC-based services, review other resources for standards in the domains of agriculture and food, and briefly discuss the future direction of agricultural semantics standards in Japan based on reviews. CAVOC has been developed as a core vocabulary for enhancing semantics-level interoperability. It specifies concepts that are frequently used to annotate agricultural data on agricultural activities and crops in Japan. The CAVOC website provides uniform resource identifiers by which the concepts in CAVOC are given. The data in CAVOC can be downloaded from the website. The extension of CAVOC coverage is important to unambiguously define objects and their relationships in the domains of agriculture and food. International collaborative efforts to create standards in agricultural semantics are underway through mapping among semantic resources within international projects and by holding meetings among stakeholders. We need to join the international community in creating agricultural semantics standards so as to extend CAVOC coverage through the utilization of foreign resources.

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The IP Multimedia Subsystem (IMS) establishes a session between end terminals as a client/server application in the Next Generation Network (NGN). These days, many application services are being provided as Web services. In this letter, we propose a new NGN architecture conforming to the architectural styles of Representational State Transfer (REST), which is a Web service technology for solving interoperability and traffic concentration problems in the Session Initiation Protocol (SIP).

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Video traffic occupies a major part of current mobile traffic. The characteristics of video traffic are dominated by the behavior of the video application users. This paper uses a state transition diagram to analyze the behavior of video application users on smart phones. Video application users are divided into two categories; keyword search users and initial screen users. They take different first action in video viewing. The result of our analysis shows that the patience of video application users depends on whether they have a specific purpose when they launch a video application or not. Mobile network operators can improve the QoE of video application users by utilizing the results of this study.

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本稿は,QRコードにカラー画像を重畳することで,QRコードの視認性・デザイン性を向上する手法を提案している.提案法は,重畳画像の輝度値を考慮することで,QRコードの復号に影響を与えない.これにより,QRコードの復号に必要な周辺余白にも画像を重畳可能となっている.この特徴に基づき,周辺余白に情報を重畳可能な別の方法についても述べている.

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The purpose is to develop educational content linking schools in remote locations by utilizing VR and 3D game engine technology. Its educational effect is evaluated by comparing the case with and without the use of VR (HMD).

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In recent years, there has been a significant growth in the importance of data mining of graph-structured data due to this technology's rapid increase in both scale and application areas. Many previous studies have investigated decision tree learning on Semantic Web-based linked data to uncover implicit knowledge. In the present paper, we suggest a new random forest algorithm for linked data to overcome the underlying limitations of the decision tree algorithm, such as local optimal decisions and generalization error. Moreover, we designed a parallel processing environment for random forest learning to manage large-size linked data and increase the efficiency of multiple tree generation. For this purpose, we modified the previous candidate feature searching method of the decision tree algorithm for linked data to reduce the feature searching space of random forest learning and developed feature selection methods that are adjusted to linked data. Using a distributed index-based search engine, we designed a parallel random forest learning system for linked data to generate random forests in parallel. Our proposed system enables users to simultaneously generate multiple decision trees from distributed stored linked data. To evaluate the performance of the proposed algorithm, we performed experiments to compare the classification accuracy when using the single decision tree algorithm. The experimental results revealed that our random forest algorithm is more accurate than the single decision tree algorithm.

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In the area of the Semantic Web, RDF datastores are required to search for metadata quickly from large scale RDF data, such as Wikidata and DBpedia in the Linked Open Data (LOD). This paper presents compressed index structures and URI dictionaries of RDF data in order to develop a fast in-memory RDF database system (called FROST). Instead of the complete six types of indexes SPO, SOP, PSO, POS, OSP, and OPS in RDF triples, FROST employs the two types of indexes SPO and OPS that enable us to compactly store RDF triples in the memory. Using the compressed index structures, we develop a fast search method in the datastore system FROST that solves SPARQL queries and returns the query answers from RDF graphs. Our experiments show that (i) FROST outperforms the inmemory RDF frameworks Jena and RDF4J with respect to both fast query processing and saved memory, using the datasets and queries of the LUBM (a benchmarking framework for semantic repositories) and BMDB (RDF Store Benchmarks with DBpedia) benchmarks, and (ii) FROST outperforms the on-disk RDF store Virtuoso with respect to fast query processing, using the LUBM benchmark.

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Several web sites providing disaster-related information failed repeatedly after the Great East Japan Earthquake, due to flash crowds caused by Twitter users. Twitter, which was intensively used for information sharing in the aftermath of the earthquake, relies on URL shorteners like bit.ly to offset its strict limit on message length. In order to mitigate the flash crowds, we examine the current Web usage and find that URL shorteners constitute a layer of indirection; a significant part of Web traffic is guided by them. This implies that flash crowds can be controlled by URL shorteners. We developed a new URL shortener, named rcdn.info, just after the earthquake; rcdn.info redirects users to a replica created on a CoralCDN, if the original site is likely to become overloaded. This surprisingly simple solution worked very well in the emergency. We also conduct a thorough analysis of the request log and present several views that capture user behavior in the emergency from various aspects. Interestingly, the traffic significantly grew up at previously unpopular (i.e., small) sites during the disaster; this traffic shift could lead to the failure of several sites. Finally, we show that rcdn.info has great potential in mitigating such failures. We believe that our experience will help the research community tackle future disasters.

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セマンティックウェブ技術を活用し様々なライフサイエンスデータとリンクすることで糖鎖機能の解明につなげることができる。糖鎖科学のポータルサイトとしてGlyCosmos Portal を開発し、ライフサイエンスデータの統合を目指す。我々はこれまで国内外の研究者と協力し糖鎖情報のオントロジーであるGlycoRDF、糖鎖構造表記 法であるWURCS、国際糖鎖構造リポジトリであるGlyTouCan を開発してきた。本ポータルは、これらの成果を活用したリポジトリとデータベースで構成される。リポジトリはGlyTouCan と複合糖質のリポジトリを開発している。また、データベースとしては、糖鎖関連の生合成経路や糖鎖の分子構造のデータを収録するGlyCosmosDB を開発している。

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Wireless cloud service is now inevitable and widely implemented to the global use. Increasing traffic demands of the smart phone and the tablet PC is the big problems due to the radio spectrum resource limitation.
Key issues to be solved in near future are the bottleneck and the throughput improvement of the wireless cloud network. Video streaming service is included in the cloud service, and their information traffic volume has most important influence on the topics. In this paper, it is proposed that the Bigdata-based Social Level Agent (SoLA), which can effectively and seamlessly offload the video streaming traffic to the microcell networks to enhance the spectrum utilization efficiency. The system is also the one of the important items of the global standardization issues. The objectives, the configurations and functional operations, and the related standardization bodies and standards are investigated. And also the strategy of the proposed system standardization is mentioned..

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E-Defense is developing a system which enables all earthquake engineering researchers to freely access to valuable experimental data obtained during shake table tests executed there after some period. EDgrid is a cyberinfrastructure being developed for this purpose by using the cutting-edge information technology with NEESit in the United States of America. In this research, a data model has been developed for storing all the data related to experiments performed at E-Defense in the EDgrid central repository correctly, effectively and efficiently. The data model was developed on the basis of the event-based relational data model theory to correspond to possible future facility expansion and collaboration with other databases in various countries.

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