Seokjin Im

Design and Development of Framework for Health Data Relay based on OAuth2 in Cloud Environment

With information technology and health care, efficient health data management provides various health services. Health data from hospitals patients and healthy persons use stacked up enables to trace health condition and to manage health effectively and to reduce healthcare cost. In this paper, we design and implement a framework for relaying health data from various hospitals to cloud storage for manage health condition. For efficient authentication of the framework with cloud storage, OAuth2 protocal is adopted. The proposed health data relay framework can be used for developing various health services with the stacked data in the cloud storage.

A Distributed Air Index Based on Maximum Boundary Rectangle over Grid-Cells for Wireless Non-Flat Spatial Data Broadcast

In the pervasive computing environment using smart devices equipped with various sensors, a wireless data broadcasting system for spatial data items is a natural way to efficiently provide a location dependent information service, regardless of the number of clients. A non-flat wireless broadcast system can support the clients in accessing quickly their preferred data items by disseminating the preferred data items more frequently than regular data on the wireless channel. To efficiently support the processing of spatial window queries in a non-flat wireless data broadcasting system, we propose a distributed air index based on a maximum boundary rectangle (MaxBR) over grid-cells (abbreviated DAIM), which uses MaxBRs for filtering out hot data items on the wireless channel. Unlike the existing index that repeats regular data items in close proximity to hot items at same frequency as hot data items in a broadcast cycle, DAIM makes it possible to repeat only hot data items in a cycle and reduces the length of the broadcast cycle. Consequently, DAIM helps the clients access the desired items quickly, improves the access time, and reduces energy consumption. In addition, a MaxBR helps the clients decide whether they have to access regular data items or not. Simulation studies show the proposed DAIM outperforms existing schemes with respect to the access time and energy consumption.

A Multi-level Grid-Based Air Indexing Scheme for Window Query Processing in Wireless Data Broadcast Environments

Air indexing schemes of spatial data items have been researched for effective processing of spatial queries. However, the schemes cause the mobile clients to wait long for their desired items and to consume energy much. In this paper, we propose a new indexing scheme based on multi-leveled grid for window query processing on air. It allows fast and energy efficient processing of window query. Also, it has a linear structure matching the linear access pattern of the clients and makes them access only the queried data items. The simulations show that the proposed scheme outperforms the existing schemes in terms of access latency and energy efficiency.