We present GridSet, a novel set visualization for exploring elements, their attributes, intersections, as well as entire sets. In this set visualization, each set representation is composed of glyphs, which represent individual elements and their attributes utilizing different visual encodings. In each set, elements are organized within a grid treemap layout that can provide space-efficient overviews of the elements structured by set intersections across multiple sets. These intersecting elements can be connected among sets through visual links. These visual representations for the individual set, elements, and intersection in GridSet facilitate novel interaction approaches for undertaking analysis tasks by utilizing both macroscopic views of sets, as well as microscopic views of elements and attribute details. In order to perform multiple set operations, GridSet supports a simple and straightforward process for set operations through dragging and dropping set objects. Our use cases involving two large set-typed datasets demonstrate that GridSet facilitates the exploration and identification of meaningful patterns and distributions of elements with respect to attributes and set intersections for solving complex analysis problems in set-typed data.

Recent advances in big data and deep learning technologies have enabled researchers across many disciplines to gain new insight into large and complex data. For example, deep neural networks are being widely used to analyze various types of data including images, videos, texts, and time-series data. In another example, various disciplines such as sociology, social work, and criminology are analyzing crowd-sourced and online social network data using big data technologies to gain new insight from a plethora of data. Even though many different types of data are being generated and analyzed in various domains, the development of distributed city-level cyberinfrastructure for effectively integrating such data to generate more value and gain insights is still not well-addressed in the research literature. In this paper, we present our current efforts and ultimate vision to build distributed cyberinfrastructure which integrates big data and deep learning technologies with a variety of data for enhancing public safety and livability in cites. We also introduce several methodologies and applications that we are developing on top of the cyberinfrastructure to support diverse community stakeholders in cities.

Korean has the advantage of omission of sentence structure and its range of formulas, so it is better to process it in morpheme analysis stage than parsing. In this paper, we propose a functional expansion method of morpheme analyzer which can reduce the burden of parsing. This method combines them into the longest matching method when a plurality of morpheme columns have a syntactic category by the estimation of unknown words, processing of compound nouns and compound verbs, processing of numbers and symbols, The proposed morpheme analysis method improves accuracy by eliminating unnecessary morphological analysis results. Experimental results show that the average parse tree is 73.4% and the parse time is 52.9%.

Online communities continue to be an important resource for informal learning. Although many facets of online learning communities have been studied, we have limited understanding of how such communities grow over time to productively engage a large number of learners. In this paper we present a study of a large online community called Scratch which was created to help users learn software programming. We analyzed 5 years of data consisting of 1 million users and their 1.9 million projects. Examination of interactional patterns among highly active members of the community uncovered a markedly temporal dimension to participation. As membership of the Scratch online community grew over time, interest-based subcultures started to emerge. This pattern was uncovered even when clustering was based solely on social network of members. This process, which closely resembles urbanism or the growth of physically populated areas, allowed new members to combine their interests with programming.

The detection and prediction of natural catastrophes or man-made disasters before they occur has recently shone the light on several relatively new technologies. Due to the significant development of mobile hardware and software technologies, a smartphone has become an important device for detecting and warning about such disasters. Specifically, disaster-related data can be collected from diverse sources including smartphones' sensors and social networks, and then the collected data are further analyzed to detect disasters and alert people about them. These collective data enable a user to have access to a variety of essential information related to disaster events. Using the example of a communicable disease outbreak, such information helps to identify and detect the ground zero of a disaster, as well as make sense of the means of transmission, progress, and patterns of the disaster. In this paper, we discuss a novel approach for analyzing and interacting with collective sensor data in a visual, real-time, and scalable fashion, offering diverse perspectives and data management components.

With the increasing demand on knowledge sharing and problem solving, there is a growing participation on online Question & Answer (Q&A) forums in the recent past. We classify the online community participation on Stack Exchange into two different genres, one is technical and another is non-technical. Though several studies have measured community activity, studies that compare activity across forums within different topic areas are limited. In this work we examine the effect of incentives on contributions by exploring the differences between technical and non-technical communities in terms of user's participation. Given the increased attention on discussion forums as part of online learning, especially MOOCs, we believe that our findings can assist with providing better support for learners across different content areas.

We analyzed informal learning in Scratch Online -- an online community with over 4.3 million users and 6.7 million user-generated content. Users develop projects, which are graphical interfaces involving manipulation of programming blocks. We investigated two fundamental questions: how can we model informal learning, and what patterns of informal learning emerge. We proceeded in two phases. First, we modeled learning as a trajectory of cumulative programming block usage by long-term users who created at least 50 projects. Second, we applied K-means++ clustering to uncover patterns of learning and corresponding subpopulations. We found four groups of users manifesting four different patterns of learning, ranging from the smallest to the largest improvement. At one end of the spectrum, users learned more and in a faster manner. At the opposite end, users did not show much learning, even after creating dozens of projects. The modeling and clustering of trajectory patterns that enabled us to quantitatively analyze informal learning may be applicable to other similar communities. The results can also support administrators of online communities in implementing customized interventions for specific subpopulations.

Researchers have been studying and developing teaching materials for information retrieval (IR), such as [3]. Toolkits also have been built that provide hands-on experience to students. For example, IR-Toolbox [4] is an effort to close the gap between the students' understanding of IR concepts and real-life indexing and search systems. Such tools might be good for helping students in non-technical areas such as in the Library and Information Science field to develop their conceptual model of search engines. However, they do not cover emerging topics and skills, such as content-based image retrieval (CBIR) and fusion search. Although there is open source software (such as those in http://www.searchtools.com/tools/tools-opensource.html) that can be used to teach basic and advanced IR topics, they require a student to have high-level technical knowledge and to spend a long time to gain a practical understanding of these topics.