Toyokazu Akiyama

Portraying Collective Spatial Attention in Twitter

Microblogging platforms such as Twitter have been recently frequently used for detecting real-time events. The spatial component, as reflected by user location, usually plays a key role in such systems. However, an often neglected source of spatial information are location mentions expressed in tweet contents. In this paper we demonstrate a novel visualization system for analyzing how Twitter users collectively talk about space and for uncovering correlations between geographical locations of Twitter users and the locations they tweet about. Our exploratory analysis is based on the development of a model of spatial information extraction and representation that allows building effective visual analytics framework for large scale datasets. We show visualization results based on half a year long dataset of Japanese tweets and a four months long collection of tweets from USA. The proposed system allows observing many space related aspects of tweet messages including the average scope of spatial attention of social media users and variances in spatial interest over time. The analytical framework we provide and the findings we outline can be valuable for scientists from diverse research areas and for any users interested in geographical and social aspects of shared online data.

Global telescience featuring IPv6 at iGrid2002

Electron tomography is a powerful technique for deriving 3D structural information from biological specimens. As advanced instrumentation, networking, and grid computing are applied to electron tomography and biological sciences in general, much work is needed to integrate and coordinate these advanced technologies in a transparent way to deliver them to the end user. The Telescience Portal (http://gridport.npaci.edu/Telescience) is a web-based solution for end-to-end electron tomography that centralizes applications and seamlessly interfaces with the grid to accelerate the throughput of data results. In this paper we will describe the architecture and design of the Telescience Portal in the context of our experiences leading up to and including the iGrid2002 workshop. We will examine the lessons learned in developing the production Telescience environment, leveraging a successful international collaboration with groups in Japan and Taiwan, building end-to-end native IPv6 networks across continents, and examining IPv6 enabled mechanisms for transferring large data from two unique, remotely accessible high performance scientific instruments. Traditional computer science communities develop next generation technologies. Applications like Telescience drive these next generation technologies into production quality applications for everyday research needs.

A new dynamical domain decomposition method for parallel molecular dynamics simulation

A new material particle dynamical domain decomposition method MPD/sup 3/ has been developed. The method is suitable for a large scale parallel molecular dynamic simulation on a heterogeneous computing net. Performance of the MPD/sup 3/ algorithm is tested in various computing environments, such as PC clusters, super computer clusters, and grid. It is shown that the MPD/sup 3/ algorithm is highly-adaptive for both computer clusters and grid computing environments, even if other programs are running on the same computer environment.

A Consideration of the Precision Improvement in WiFi Positioning System

Recently, WiFi Positioning System (WPS) plays important role in ubiquitous applications. The main problem of WPS is how to collect WiFi Access Point(AP) locations because the most of the APs are usually installed on grass-root basis and their locations are not published.We use Locky.jp provided by Nagoya University Research Group as a WPS for our ubiquitous applications. However the precision of the AP location data in Locky.jp is not enough for our applications. To improve the precision of the AP location database, we are going to apply statistical and heuristic methods. In this paper, we described the overview of our heuristic approach and define the quality of AP observation logs and location data. We also evaluated the quality definition by simple simulations.

ResilientFlow: Deployments of distributed control channel maintenance modules to recover SDN from unexpected failures

To protect SDN-enabled networks under large-scale, unexpected link failures, we propose ResilientFlow that deploys distributed modules called Control Channel Maintenance Module (CCMM) for every switch and controllers. The CCMMs makes switches able to maintain their own control channels, which are core and fundamental part of SDN. In this paper, we design, implement, and evaluate the ResilientFlow.

Integration of computational fluid dynamics and computational aero acoustics on grid for dental applications

The hybrid applications are needed in dental research because the result of their operation could be predicted by both modeling of an oral truct and more than two kind of physical simulations. However, it takes long time to perform the hybrid applications, cost a lot of money and needs some experience to deal with them. This paper proposes a new execution procedure of two applications which can reduce the implementation time by considering parallel efficiency of those applications. It can determine which attitude should be taken, sequential or separate execution of two different applications related with each other. Following the execution procedure, the dental hybrid application was performed. As a result of that, desirable pairs of the number of CPUs allocated to each simulation could be found. This means that the adequate procedure should be considered before execution of the hybrid applications, in order to play a compute power producer for dental clinics and hospitals.

Lets not stare at smartphones while walking: memorable route recommendation by detecting effective landmarks

Navigation in unfamiliar cities often requires frequent map checking, which is troublesome for wayfinders. We propose a novel approach for improving real-world navigation by generating short, memorable and intuitive routes. To do so we detect useful landmarks for effective route navigation. This is done by exploiting not only geographic data but also crowd footprints in Social Network Services (SNS) and Location Based Social Networks (LBSN). Specifically, we detect point, area, and line landmarks by using three indicators to measure landmarks utility: visit popularity, direct visibility, and indirect visibility. We then construct an effective route graph based on the extracted landmarks, which facilitates optimal path search. In the experiments, we show that landmark-based routes out-perform the ones created by baseline from the perspectives of the lap time and the number of references necessary to check self-positions for adjusting route directions.

Simultaneous realization of page-centric communication and search

We present a novel system that combines the advantages of social communication and Web search by simultaneously discovering important pages and users. First, the system provides a communication interface attached to pages, which allows users to talk with each other in real time while browsing the same page, i.e., page-centric communication. Then, the system can efficiently provide two ranking lists of pages and users by analyzing a hybrid structure of hyperlinks (page-page relationship) and social links (page-user relationship and user-user relationship). Thus, users can efficiently search for important pages as well as important users related to their queries through the ranking function, and immediately obtain useful information or knowledge from not only pages themselves but also from other users.

TwinChat: A Twitter and Web User Interactive Chat System

This paper presents TWinChat, a Twitter and Web user interactive chat system to support simultaneous communication between microbloggers and Web users in real-time through both the contents of microblogs and Web pages. TWinChat provides a question answering interface attached to Web pages, which allows Web users to chat with Twitter users in real-time while presenting tweets that are associated with Web pages, i.e., simultaneous cross-media communication. In order to map heterogeneous media, the system extracts relationship between tweets and Web pages by generating queries based on location names. Thus, our system can effectively present messages from Web users to help Twitter users immediately obtain useful information or knowledge, and it also can effectively present tweets from the Twitter users to help the Web users easily grasp the current situation in real-time.

FESTIVAL: Towards an Intercontinental Federation Approach

In the last years, in both Europe and Japan, several initiatives have been started with the aim of building and testing Internet of Things and Smart ICT architectures and platforms to address specific domain issues through designed solutions. FESTIVAL EU-Japan collaborative project aims at federating these testbeds, making them interoperable, allowing centralized data collection and analyzing societal issues in both cultures, all of it under a user privacy-preserving context. In this sense, FESTIVAL pursues a twofold approach: firstly, the intercontinental federation of testbeds in Japan and Europe using existing tools as well as developing new ones; and secondly, the creation of new services and experiments, to be performed on top of the FESTIVAL testbeds and experimentation facilities, associated to three different smart city domains: smart energy, smart building and smart shopping. Throughout this article the current status of the project (in its first year) is shown, describing the Experimentation as a Service federation approach to be implemented, with a first analysis of the platforms and testbeds that are included within the project. Furthermore, the paper also describes the services and use cases that will be conducted within FESTIVAL lifespan. Finally, next steps to be carried out in the coming years of the project are indicated.